[v8,0/6] iio/adc: ingenic: Cleanups & add touchscreen mode.

Message ID	20200709152200.10039-1-contact@artur-rojek.eu
Headers	show Return-Path: <devicetree-owner@vger.kernel.org> sender: contact@artur-rojek.eu) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id 0CCBEC000B; Thu, 9 Jul 2020 15:22:34 +0000 (UTC) From: Artur Rojek <contact@artur-rojek.eu> To: Dmitry Torokhov <dmitry.torokhov@gmail.com>, Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Jonathan Cameron <jic23@kernel.org>, Paul Cercueil <paul@crapouillou.net>, Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Heiko Stuebner <heiko@sntech.de>, Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>, devicetree@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Artur Rojek <contact@artur-rojek.eu> Subject: [PATCH v8 0/6] iio/adc: ingenic: Cleanups & add touchscreen mode. Date: Thu, 9 Jul 2020 17:21:54 +0200 Message-Id: <20200709152200.10039-1-contact@artur-rojek.eu> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: devicetree-owner@vger.kernel.org Precedence: bulk
Series	iio/adc: ingenic: Cleanups & add touchscreen mode. \| expand [v8,0/6] iio/adc: ingenic: Cleanups & add touchscreen mode. [v8,1/6] dt-bindings: iio/adc: Convert ingenic-adc docs to YAML. [v8,5/6] dt-bindings: iio/adc: Add touchscreen idx for JZ47xx SoC ADC

Artur Rojek July 9, 2020, 3:21 p.m. UTC

Hi all,

v8 of this patchset introduces some structural changes, which I deemed
worthy highlighting here:

 - adc-joystick related changes have been dropped from this patchset and
   will be upstreamed separately. Their only connection to this patchset
   was that they used INGENIC_ADC_TOUCH_* defines in the DTS example,
   causing trouble to Rob's scripts.

 - Integrated Paul's changes, which introduce an ADCMD low-level command
   feature. These changes affect patches 5/6 and 6/6, with the former
   requiring Rob to re-ack.

Cheers,
Artur

Artur Rojek (5):
  dt-bindings: iio/adc: Convert ingenic-adc docs to YAML.
  IIO: Ingenic JZ47xx: Error check clk_enable calls.
  IIO: Ingenic JZ47xx: Add xlate cb to retrieve correct channel idx
  dt-bindings: iio/adc: Add touchscreen idx for JZ47xx SoC ADC
  IIO: Ingenic JZ47xx: Add touchscreen mode.

Paul Cercueil (1):
  iio/adc: ingenic: Retrieve channels list from soc data struct

 .../bindings/iio/adc/ingenic,adc.txt          |  49 ---
 .../bindings/iio/adc/ingenic,adc.yaml         |  71 ++++
 drivers/iio/adc/Kconfig                       |   1 +
 drivers/iio/adc/ingenic-adc.c                 | 386 ++++++++++++++++--
 include/dt-bindings/iio/adc/ingenic,adc.h     |   6 +
 5 files changed, 426 insertions(+), 87 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/iio/adc/ingenic,adc.txt
 create mode 100644 Documentation/devicetree/bindings/iio/adc/ingenic,adc.yaml

Andy Shevchenko July 9, 2020, 3:43 p.m. UTC | #1

On Thu, Jul 9, 2020 at 6:22 PM Artur Rojek <contact@artur-rojek.eu> wrote:
>
> Hi all,
>
> v8 of this patchset introduces some structural changes, which I deemed
> worthy highlighting here:

Can you remind me if I gave you tags on the previous version?
If so, is the above the reason to drop them?

>
>  - adc-joystick related changes have been dropped from this patchset and
>    will be upstreamed separately. Their only connection to this patchset
>    was that they used INGENIC_ADC_TOUCH_* defines in the DTS example,
>    causing trouble to Rob's scripts.
>
>  - Integrated Paul's changes, which introduce an ADCMD low-level command
>    feature. These changes affect patches 5/6 and 6/6, with the former
>    requiring Rob to re-ack.
>
> Cheers,
> Artur
>
> Artur Rojek (5):
>   dt-bindings: iio/adc: Convert ingenic-adc docs to YAML.
>   IIO: Ingenic JZ47xx: Error check clk_enable calls.
>   IIO: Ingenic JZ47xx: Add xlate cb to retrieve correct channel idx
>   dt-bindings: iio/adc: Add touchscreen idx for JZ47xx SoC ADC
>   IIO: Ingenic JZ47xx: Add touchscreen mode.
>
> Paul Cercueil (1):
>   iio/adc: ingenic: Retrieve channels list from soc data struct
>
>  .../bindings/iio/adc/ingenic,adc.txt          |  49 ---
>  .../bindings/iio/adc/ingenic,adc.yaml         |  71 ++++
>  drivers/iio/adc/Kconfig                       |   1 +
>  drivers/iio/adc/ingenic-adc.c                 | 386 ++++++++++++++++--
>  include/dt-bindings/iio/adc/ingenic,adc.h     |   6 +
>  5 files changed, 426 insertions(+), 87 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/iio/adc/ingenic,adc.txt
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/ingenic,adc.yaml
>
> --
> 2.27.0
>

Artur Rojek July 9, 2020, 4:05 p.m. UTC | #2

Hey Andy,

On 2020-07-09 17:43, Andy Shevchenko wrote:
> On Thu, Jul 9, 2020 at 6:22 PM Artur Rojek <contact@artur-rojek.eu> 
> wrote:
>> 
>> Hi all,
>> 
>> v8 of this patchset introduces some structural changes, which I deemed
>> worthy highlighting here:
> 
> Can you remind me if I gave you tags on the previous version?
I received no tags from you on this patchset so far.

Cheers,
Artur

> If so, is the above the reason to drop them?
> 
>> 
>>  - adc-joystick related changes have been dropped from this patchset 
>> and
>>    will be upstreamed separately. Their only connection to this 
>> patchset
>>    was that they used INGENIC_ADC_TOUCH_* defines in the DTS example,
>>    causing trouble to Rob's scripts.
>> 
>>  - Integrated Paul's changes, which introduce an ADCMD low-level 
>> command
>>    feature. These changes affect patches 5/6 and 6/6, with the former
>>    requiring Rob to re-ack.
>> 
>> Cheers,
>> Artur
>> 
>> Artur Rojek (5):
>>   dt-bindings: iio/adc: Convert ingenic-adc docs to YAML.
>>   IIO: Ingenic JZ47xx: Error check clk_enable calls.
>>   IIO: Ingenic JZ47xx: Add xlate cb to retrieve correct channel idx
>>   dt-bindings: iio/adc: Add touchscreen idx for JZ47xx SoC ADC
>>   IIO: Ingenic JZ47xx: Add touchscreen mode.
>> 
>> Paul Cercueil (1):
>>   iio/adc: ingenic: Retrieve channels list from soc data struct
>> 
>>  .../bindings/iio/adc/ingenic,adc.txt          |  49 ---
>>  .../bindings/iio/adc/ingenic,adc.yaml         |  71 ++++
>>  drivers/iio/adc/Kconfig                       |   1 +
>>  drivers/iio/adc/ingenic-adc.c                 | 386 
>> ++++++++++++++++--
>>  include/dt-bindings/iio/adc/ingenic,adc.h     |   6 +
>>  5 files changed, 426 insertions(+), 87 deletions(-)
>>  delete mode 100644 
>> Documentation/devicetree/bindings/iio/adc/ingenic,adc.txt
>>  create mode 100644 
>> Documentation/devicetree/bindings/iio/adc/ingenic,adc.yaml
>> 
>> --
>> 2.27.0
>>

Andy Shevchenko July 9, 2020, 4:42 p.m. UTC | #3

On Thu, Jul 9, 2020 at 7:05 PM Artur Rojek <contact@artur-rojek.eu> wrote:
>
> Hey Andy,
>
> On 2020-07-09 17:43, Andy Shevchenko wrote:
> > On Thu, Jul 9, 2020 at 6:22 PM Artur Rojek <contact@artur-rojek.eu>
> > wrote:
> >>
> >> Hi all,
> >>
> >> v8 of this patchset introduces some structural changes, which I deemed
> >> worthy highlighting here:
> >
> > Can you remind me if I gave you tags on the previous version?
> I received no tags from you on this patchset so far.

Thanks for reminding me!

Jonathan Cameron July 12, 2020, 12:02 p.m. UTC | #4

On Thu,  9 Jul 2020 17:21:56 +0200
Artur Rojek <contact@artur-rojek.eu> wrote:

> Introduce error checks for the clk_enable calls used in this driver.
> As part of the changes, move clk_enable/clk_disable calls out of
> ingenic_adc_set_config and into respective logic of its callers.
> 
> Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> Tested-by: Paul Cercueil <paul@crapouillou.net>
Applied.

Thanks,

Jonathan

> ---
> 
>  Changes:
> 
>  v6: new patch
> 
>  v7: no change
> 
>  v8: move `clk_disable` outside the lock
> 
>  drivers/iio/adc/ingenic-adc.c | 25 +++++++++++++++++++++----
>  1 file changed, 21 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
> index 39c0a609fc94..c1946a9f1cca 100644
> --- a/drivers/iio/adc/ingenic-adc.c
> +++ b/drivers/iio/adc/ingenic-adc.c
> @@ -73,7 +73,6 @@ static void ingenic_adc_set_config(struct ingenic_adc *adc,
>  {
>  	uint32_t cfg;
>  
> -	clk_enable(adc->clk);
>  	mutex_lock(&adc->lock);
>  
>  	cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
> @@ -81,7 +80,6 @@ static void ingenic_adc_set_config(struct ingenic_adc *adc,
>  	writel(cfg, adc->base + JZ_ADC_REG_CFG);
>  
>  	mutex_unlock(&adc->lock);
> -	clk_disable(adc->clk);
>  }
>  
>  static void ingenic_adc_enable(struct ingenic_adc *adc,
> @@ -124,6 +122,8 @@ static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
>  				 long m)
>  {
>  	struct ingenic_adc *adc = iio_priv(iio_dev);
> +	struct device *dev = iio_dev->dev.parent;
> +	int ret;
>  
>  	switch (m) {
>  	case IIO_CHAN_INFO_SCALE:
> @@ -131,6 +131,14 @@ static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
>  		case INGENIC_ADC_BATTERY:
>  			if (!adc->soc_data->battery_vref_mode)
>  				return -EINVAL;
> +
> +			ret = clk_enable(adc->clk);
> +			if (ret) {
> +				dev_err(dev, "Failed to enable clock: %d\n",
> +					ret);
> +				return ret;
> +			}
> +
>  			if (val > JZ_ADC_BATTERY_LOW_VREF) {
>  				ingenic_adc_set_config(adc,
>  						       JZ_ADC_REG_CFG_BAT_MD,
> @@ -142,6 +150,9 @@ static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
>  						       JZ_ADC_REG_CFG_BAT_MD);
>  				adc->low_vref_mode = true;
>  			}
> +
> +			clk_disable(adc->clk);
> +
>  			return 0;
>  		default:
>  			return -EINVAL;
> @@ -317,6 +328,13 @@ static int ingenic_adc_read_chan_info_raw(struct ingenic_adc *adc,
>  					  int *val)
>  {
>  	int bit, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
> +	struct device *dev = iio_priv_to_dev(adc)->dev.parent;
> +
> +	ret = clk_enable(adc->clk);
> +	if (ret) {
> +		dev_err(dev, "Failed to enable clock: %d\n", ret);
> +		return ret;
> +	}
>  
>  	/* We cannot sample AUX/AUX2 in parallel. */
>  	mutex_lock(&adc->aux_lock);
> @@ -325,7 +343,6 @@ static int ingenic_adc_read_chan_info_raw(struct ingenic_adc *adc,
>  		ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, bit);
>  	}
>  
> -	clk_enable(adc->clk);
>  	ret = ingenic_adc_capture(adc, engine);
>  	if (ret)
>  		goto out;
> @@ -342,8 +359,8 @@ static int ingenic_adc_read_chan_info_raw(struct ingenic_adc *adc,
>  
>  	ret = IIO_VAL_INT;
>  out:
> -	clk_disable(adc->clk);
>  	mutex_unlock(&adc->aux_lock);
> +	clk_disable(adc->clk);
>  
>  	return ret;
>  }

Jonathan Cameron July 12, 2020, 12:05 p.m. UTC | #5

On Thu,  9 Jul 2020 17:21:57 +0200
Artur Rojek <contact@artur-rojek.eu> wrote:

> Provide an of_xlate callback in order to retrieve the correct channel
> specifier index from the IIO channels array.
> 
> Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> Tested-by: Paul Cercueil <paul@crapouillou.net>
Applied.  Thanks,

Jonathan

> ---
> 
>  Changes:
> 
>  v2-v8: no change
> 
>  drivers/iio/adc/ingenic-adc.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
> index c1946a9f1cca..89019fb59d48 100644
> --- a/drivers/iio/adc/ingenic-adc.c
> +++ b/drivers/iio/adc/ingenic-adc.c
> @@ -400,6 +400,21 @@ static int ingenic_adc_read_raw(struct iio_dev *iio_dev,
>  	}
>  }
>  
> +static int ingenic_adc_of_xlate(struct iio_dev *iio_dev,
> +				const struct of_phandle_args *iiospec)
> +{
> +	int i;
> +
> +	if (!iiospec->args_count)
> +		return -EINVAL;
> +
> +	for (i = 0; i < iio_dev->num_channels; ++i)
> +		if (iio_dev->channels[i].channel == iiospec->args[0])
> +			return i;
> +
> +	return -EINVAL;
> +}
> +
>  static void ingenic_adc_clk_cleanup(void *data)
>  {
>  	clk_unprepare(data);
> @@ -409,6 +424,7 @@ static const struct iio_info ingenic_adc_info = {
>  	.write_raw = ingenic_adc_write_raw,
>  	.read_raw = ingenic_adc_read_raw,
>  	.read_avail = ingenic_adc_read_avail,
> +	.of_xlate = ingenic_adc_of_xlate,
>  };
>  
>  static const struct iio_chan_spec ingenic_channels[] = {

Jonathan Cameron July 12, 2020, 12:07 p.m. UTC | #6

On Thu,  9 Jul 2020 17:21:58 +0200
Artur Rojek <contact@artur-rojek.eu> wrote:

> From: Paul Cercueil <paul@crapouillou.net>
> 
> Instead of having one array of struct iio_chan_spec for all SoCs, and
> have some SoCs remove the last item of the array as they can't use it,
> have each SoC define its array of supported channels.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Tested-by: Artur Rojek <contact@artur-rojek.eu>
Applied to the togreg branch of iio.git and pushed out as testing for
autobuilders to play with it.

Thanks,

Jonathan

> ---
> 
>  Changes:
> 
>  v8: new patch
> 
>  drivers/iio/adc/ingenic-adc.c | 99 +++++++++++++++++++++++------------
>  1 file changed, 65 insertions(+), 34 deletions(-)
> 
> diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
> index 89019fb59d48..0233a9055c86 100644
> --- a/drivers/iio/adc/ingenic-adc.c
> +++ b/drivers/iio/adc/ingenic-adc.c
> @@ -55,6 +55,8 @@ struct ingenic_adc_soc_data {
>  	size_t battery_scale_avail_size;
>  	unsigned int battery_vref_mode: 1;
>  	unsigned int has_aux2: 1;
> +	const struct iio_chan_spec *channels;
> +	unsigned int num_channels;
>  	int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
>  };
>  
> @@ -262,6 +264,61 @@ static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
>  	return 0;
>  }
>  
> +static const struct iio_chan_spec jz4740_channels[] = {
> +	{
> +		.extend_name = "aux",
> +		.type = IIO_VOLTAGE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_AUX,
> +		.scan_index = -1,
> +	},
> +	{
> +		.extend_name = "battery",
> +		.type = IIO_VOLTAGE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> +						BIT(IIO_CHAN_INFO_SCALE),
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_BATTERY,
> +		.scan_index = -1,
> +	},
> +};
> +
> +static const struct iio_chan_spec jz4770_channels[] = {
> +	{
> +		.extend_name = "aux",
> +		.type = IIO_VOLTAGE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_AUX,
> +		.scan_index = -1,
> +	},
> +	{
> +		.extend_name = "battery",
> +		.type = IIO_VOLTAGE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> +						BIT(IIO_CHAN_INFO_SCALE),
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_BATTERY,
> +		.scan_index = -1,
> +	},
> +	{
> +		.extend_name = "aux2",
> +		.type = IIO_VOLTAGE,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_AUX2,
> +		.scan_index = -1,
> +	},
> +};
> +
>  static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
>  	.battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF,
>  	.battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
> @@ -271,6 +328,8 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
>  	.battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail),
>  	.battery_vref_mode = true,
>  	.has_aux2 = false,
> +	.channels = jz4740_channels,
> +	.num_channels = ARRAY_SIZE(jz4740_channels),
>  	.init_clk_div = jz4725b_adc_init_clk_div,
>  };
>  
> @@ -283,6 +342,8 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
>  	.battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail),
>  	.battery_vref_mode = true,
>  	.has_aux2 = false,
> +	.channels = jz4740_channels,
> +	.num_channels = ARRAY_SIZE(jz4740_channels),
>  	.init_clk_div = NULL, /* no ADCLK register on JZ4740 */
>  };
>  
> @@ -295,6 +356,8 @@ static const struct ingenic_adc_soc_data jz4770_adc_soc_data = {
>  	.battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail),
>  	.battery_vref_mode = false,
>  	.has_aux2 = true,
> +	.channels = jz4770_channels,
> +	.num_channels = ARRAY_SIZE(jz4770_channels),
>  	.init_clk_div = jz4770_adc_init_clk_div,
>  };
>  
> @@ -427,35 +490,6 @@ static const struct iio_info ingenic_adc_info = {
>  	.of_xlate = ingenic_adc_of_xlate,
>  };
>  
> -static const struct iio_chan_spec ingenic_channels[] = {
> -	{
> -		.extend_name = "aux",
> -		.type = IIO_VOLTAGE,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> -				      BIT(IIO_CHAN_INFO_SCALE),
> -		.indexed = 1,
> -		.channel = INGENIC_ADC_AUX,
> -	},
> -	{
> -		.extend_name = "battery",
> -		.type = IIO_VOLTAGE,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> -				      BIT(IIO_CHAN_INFO_SCALE),
> -		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> -						BIT(IIO_CHAN_INFO_SCALE),
> -		.indexed = 1,
> -		.channel = INGENIC_ADC_BATTERY,
> -	},
> -	{ /* Must always be last in the array. */
> -		.extend_name = "aux2",
> -		.type = IIO_VOLTAGE,
> -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> -				      BIT(IIO_CHAN_INFO_SCALE),
> -		.indexed = 1,
> -		.channel = INGENIC_ADC_AUX2,
> -	},
> -};
> -
>  static int ingenic_adc_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
> @@ -517,11 +551,8 @@ static int ingenic_adc_probe(struct platform_device *pdev)
>  	iio_dev->dev.parent = dev;
>  	iio_dev->name = "jz-adc";
>  	iio_dev->modes = INDIO_DIRECT_MODE;
> -	iio_dev->channels = ingenic_channels;
> -	iio_dev->num_channels = ARRAY_SIZE(ingenic_channels);
> -	/* Remove AUX2 from the list of supported channels. */
> -	if (!adc->soc_data->has_aux2)
> -		iio_dev->num_channels -= 1;
> +	iio_dev->channels = soc_data->channels;
> +	iio_dev->num_channels = soc_data->num_channels;
>  	iio_dev->info = &ingenic_adc_info;
>  
>  	ret = devm_iio_device_register(dev, iio_dev);

Jonathan Cameron July 12, 2020, 12:11 p.m. UTC | #7

On Sun, 12 Jul 2020 13:07:13 +0100
Jonathan Cameron <jic23@kernel.org> wrote:

> On Thu,  9 Jul 2020 17:21:58 +0200
> Artur Rojek <contact@artur-rojek.eu> wrote:
> 
> > From: Paul Cercueil <paul@crapouillou.net>
> > 
> > Instead of having one array of struct iio_chan_spec for all SoCs, and
> > have some SoCs remove the last item of the array as they can't use it,
> > have each SoC define its array of supported channels.
> > 
> > Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> > Tested-by: Artur Rojek <contact@artur-rojek.eu>  
> Applied to the togreg branch of iio.git and pushed out as testing for
> autobuilders to play with it.
Actually removed from tree again.

Artur, as you sent this patch on to me, you need to sign-off on it
so we maintain the DCO related records of how this got to the kernel.
You can just reply here to give it.

Thanks,

Jonathan

> 
> Thanks,
> 
> Jonathan
> 
> > ---
> > 
> >  Changes:
> > 
> >  v8: new patch
> > 
> >  drivers/iio/adc/ingenic-adc.c | 99 +++++++++++++++++++++++------------
> >  1 file changed, 65 insertions(+), 34 deletions(-)
> > 
> > diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
> > index 89019fb59d48..0233a9055c86 100644
> > --- a/drivers/iio/adc/ingenic-adc.c
> > +++ b/drivers/iio/adc/ingenic-adc.c
> > @@ -55,6 +55,8 @@ struct ingenic_adc_soc_data {
> >  	size_t battery_scale_avail_size;
> >  	unsigned int battery_vref_mode: 1;
> >  	unsigned int has_aux2: 1;
> > +	const struct iio_chan_spec *channels;
> > +	unsigned int num_channels;
> >  	int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
> >  };
> >  
> > @@ -262,6 +264,61 @@ static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
> >  	return 0;
> >  }
> >  
> > +static const struct iio_chan_spec jz4740_channels[] = {
> > +	{
> > +		.extend_name = "aux",
> > +		.type = IIO_VOLTAGE,
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > +				      BIT(IIO_CHAN_INFO_SCALE),
> > +		.indexed = 1,
> > +		.channel = INGENIC_ADC_AUX,
> > +		.scan_index = -1,
> > +	},
> > +	{
> > +		.extend_name = "battery",
> > +		.type = IIO_VOLTAGE,
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > +				      BIT(IIO_CHAN_INFO_SCALE),
> > +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> > +						BIT(IIO_CHAN_INFO_SCALE),
> > +		.indexed = 1,
> > +		.channel = INGENIC_ADC_BATTERY,
> > +		.scan_index = -1,
> > +	},
> > +};
> > +
> > +static const struct iio_chan_spec jz4770_channels[] = {
> > +	{
> > +		.extend_name = "aux",
> > +		.type = IIO_VOLTAGE,
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > +				      BIT(IIO_CHAN_INFO_SCALE),
> > +		.indexed = 1,
> > +		.channel = INGENIC_ADC_AUX,
> > +		.scan_index = -1,
> > +	},
> > +	{
> > +		.extend_name = "battery",
> > +		.type = IIO_VOLTAGE,
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > +				      BIT(IIO_CHAN_INFO_SCALE),
> > +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> > +						BIT(IIO_CHAN_INFO_SCALE),
> > +		.indexed = 1,
> > +		.channel = INGENIC_ADC_BATTERY,
> > +		.scan_index = -1,
> > +	},
> > +	{
> > +		.extend_name = "aux2",
> > +		.type = IIO_VOLTAGE,
> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > +				      BIT(IIO_CHAN_INFO_SCALE),
> > +		.indexed = 1,
> > +		.channel = INGENIC_ADC_AUX2,
> > +		.scan_index = -1,
> > +	},
> > +};
> > +
> >  static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
> >  	.battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF,
> >  	.battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
> > @@ -271,6 +328,8 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail),
> >  	.battery_vref_mode = true,
> >  	.has_aux2 = false,
> > +	.channels = jz4740_channels,
> > +	.num_channels = ARRAY_SIZE(jz4740_channels),
> >  	.init_clk_div = jz4725b_adc_init_clk_div,
> >  };
> >  
> > @@ -283,6 +342,8 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail),
> >  	.battery_vref_mode = true,
> >  	.has_aux2 = false,
> > +	.channels = jz4740_channels,
> > +	.num_channels = ARRAY_SIZE(jz4740_channels),
> >  	.init_clk_div = NULL, /* no ADCLK register on JZ4740 */
> >  };
> >  
> > @@ -295,6 +356,8 @@ static const struct ingenic_adc_soc_data jz4770_adc_soc_data = {
> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail),
> >  	.battery_vref_mode = false,
> >  	.has_aux2 = true,
> > +	.channels = jz4770_channels,
> > +	.num_channels = ARRAY_SIZE(jz4770_channels),
> >  	.init_clk_div = jz4770_adc_init_clk_div,
> >  };
> >  
> > @@ -427,35 +490,6 @@ static const struct iio_info ingenic_adc_info = {
> >  	.of_xlate = ingenic_adc_of_xlate,
> >  };
> >  
> > -static const struct iio_chan_spec ingenic_channels[] = {
> > -	{
> > -		.extend_name = "aux",
> > -		.type = IIO_VOLTAGE,
> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > -				      BIT(IIO_CHAN_INFO_SCALE),
> > -		.indexed = 1,
> > -		.channel = INGENIC_ADC_AUX,
> > -	},
> > -	{
> > -		.extend_name = "battery",
> > -		.type = IIO_VOLTAGE,
> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > -				      BIT(IIO_CHAN_INFO_SCALE),
> > -		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
> > -						BIT(IIO_CHAN_INFO_SCALE),
> > -		.indexed = 1,
> > -		.channel = INGENIC_ADC_BATTERY,
> > -	},
> > -	{ /* Must always be last in the array. */
> > -		.extend_name = "aux2",
> > -		.type = IIO_VOLTAGE,
> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> > -				      BIT(IIO_CHAN_INFO_SCALE),
> > -		.indexed = 1,
> > -		.channel = INGENIC_ADC_AUX2,
> > -	},
> > -};
> > -
> >  static int ingenic_adc_probe(struct platform_device *pdev)
> >  {
> >  	struct device *dev = &pdev->dev;
> > @@ -517,11 +551,8 @@ static int ingenic_adc_probe(struct platform_device *pdev)
> >  	iio_dev->dev.parent = dev;
> >  	iio_dev->name = "jz-adc";
> >  	iio_dev->modes = INDIO_DIRECT_MODE;
> > -	iio_dev->channels = ingenic_channels;
> > -	iio_dev->num_channels = ARRAY_SIZE(ingenic_channels);
> > -	/* Remove AUX2 from the list of supported channels. */
> > -	if (!adc->soc_data->has_aux2)
> > -		iio_dev->num_channels -= 1;
> > +	iio_dev->channels = soc_data->channels;
> > +	iio_dev->num_channels = soc_data->num_channels;
> >  	iio_dev->info = &ingenic_adc_info;
> >  
> >  	ret = devm_iio_device_register(dev, iio_dev);  
>

Jonathan Cameron July 12, 2020, 1:19 p.m. UTC | #8

On Thu,  9 Jul 2020 17:22:00 +0200
Artur Rojek <contact@artur-rojek.eu> wrote:

> The SADC component in JZ47xx SoCs provides support for touchscreen
> operations (pen position and pen down pressure) in single-ended and
> differential modes.
> 
> The touchscreen component of SADC takes a significant time to stabilize
> after first receiving the clock and a delay of 50ms has been empirically
> proven to be a safe value before data sampling can begin.
> 
> Of the known hardware to use this controller, GCW Zero and Anbernic RG-350
> utilize the touchscreen mode by having their joystick(s) attached to the
> X/Y positive/negative input pins.
> 
> JZ4770 and later SoCs introduce a low-level command feature. With it, up
> to 32 commands can be programmed, each one corresponding to a sampling
> job. It allows to change the low-voltage reference, the high-voltage
> reference, have them connected to VCC, GND, or one of the X-/X+ or Y-/Y+
> pins.
> 
> This patch introduces support for 6 stream-capable channels:
> - channel #0 samples X+/GND
> - channel #1 samples Y+/GND
> - channel #2 samples X-/GND
> - channel #3 samples Y-/GND
> - channel #4 samples X+/X-
> - channel #5 samples Y+/Y-

The one thing I noticed on this read was that we are slightly stretching
the normal IIO channel definitions.  The claim is that each of these channels
is a POSITIONREALTIVE channel, whereas that isn't really true.  They are
related to the position, but as I understand it not directly measuring it
(particularly X+ - X-) which is pretty much a reference voltage (I think!)

We might be better off just describing these as voltage channels, with
4 and 5 described as differential voltage channels.  The problem there
being that it doesn't describe the fact that the measurements are with
particular voltages also being applied to the touch screen.

Perhaps we are best off just leaving it as you have it and being a bit
'odd'.  What do you think?  Having written this down I think perhaps leaving
it alone is the best plan :(

Otherwise this all looks fine to me.

Thanks,

Jonathan

> 
> Being able to sample X-/GND and Y-/GND is useful on some devices, where
> one joystick is connected to the X+/Y+ pins, and a second joystick is
> connected to the X-/Y- pins.
> 
> All the boards which probe this driver have the interrupt provided from
> Device Tree, with no need to handle a case where the IRQ was not provided.
> 
> Co-developed-by: Paul Cercueil <paul@crapouillou.net>
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> ---
> 
>  Changes:
> 
>  v2: - improve description of the touchscreen mode,
>      - get rid of the unneeded kfifo,
>      - drop IIO_BUFFER_CB from Kconfig,
>      - remove extended names from the touchscreen channels
> 
>  v3: remove unneeded `linux/iio/kfifo_buf.h` include
> 
>  v4: clarify irq provider source in the patch description
> 
>  v5: no change
> 
>  v6: - correct the spelling of Device Tree and IRQ in commit message
>      - don't omit trailing commas from initializer lists
>      - error check `clk_enable`
>      - remove redundant `dev_err` from `platform_get_irq` error check
> 
>  v7: no change
> 
>  v8: add support for ADCMD low-level command feature
> 
>  drivers/iio/adc/Kconfig       |   1 +
>  drivers/iio/adc/ingenic-adc.c | 250 +++++++++++++++++++++++++++++++++-
>  2 files changed, 249 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> index ff3569635ce0..5b57437cef75 100644
> --- a/drivers/iio/adc/Kconfig
> +++ b/drivers/iio/adc/Kconfig
> @@ -500,6 +500,7 @@ config INA2XX_ADC
>  config INGENIC_ADC
>  	tristate "Ingenic JZ47xx SoCs ADC driver"
>  	depends on MIPS || COMPILE_TEST
> +	select IIO_BUFFER
>  	help
>  	  Say yes here to build support for the Ingenic JZ47xx SoCs ADC unit.
>  
> diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
> index 0233a9055c86..976aea46fede 100644
> --- a/drivers/iio/adc/ingenic-adc.c
> +++ b/drivers/iio/adc/ingenic-adc.c
> @@ -8,7 +8,9 @@
>  
>  #include <dt-bindings/iio/adc/ingenic,adc.h>
>  #include <linux/clk.h>
> +#include <linux/iio/buffer.h>
>  #include <linux/iio/iio.h>
> +#include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/iopoll.h>
>  #include <linux/kernel.h>
> @@ -20,19 +22,46 @@
>  #define JZ_ADC_REG_CFG			0x04
>  #define JZ_ADC_REG_CTRL			0x08
>  #define JZ_ADC_REG_STATUS		0x0c
> +#define JZ_ADC_REG_ADSAME		0x10
> +#define JZ_ADC_REG_ADWAIT		0x14
>  #define JZ_ADC_REG_ADTCH		0x18
>  #define JZ_ADC_REG_ADBDAT		0x1c
>  #define JZ_ADC_REG_ADSDAT		0x20
> +#define JZ_ADC_REG_ADCMD		0x24
>  #define JZ_ADC_REG_ADCLK		0x28
>  
>  #define JZ_ADC_REG_ENABLE_PD		BIT(7)
>  #define JZ_ADC_REG_CFG_AUX_MD		(BIT(0) | BIT(1))
>  #define JZ_ADC_REG_CFG_BAT_MD		BIT(4)
> +#define JZ_ADC_REG_CFG_SAMPLE_NUM(n)	((n) << 10)
> +#define JZ_ADC_REG_CFG_PULL_UP(n)	((n) << 16)
> +#define JZ_ADC_REG_CFG_CMD_SEL		BIT(22)
> +#define JZ_ADC_REG_CFG_TOUCH_OPS_MASK	(BIT(31) | GENMASK(23, 10))
>  #define JZ_ADC_REG_ADCLK_CLKDIV_LSB	0
>  #define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB	16
>  #define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB	8
>  #define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB	16
>  
> +#define JZ_ADC_REG_ADCMD_YNADC		BIT(7)
> +#define JZ_ADC_REG_ADCMD_YPADC		BIT(8)
> +#define JZ_ADC_REG_ADCMD_XNADC		BIT(9)
> +#define JZ_ADC_REG_ADCMD_XPADC		BIT(10)
> +#define JZ_ADC_REG_ADCMD_VREFPYP	BIT(11)
> +#define JZ_ADC_REG_ADCMD_VREFPXP	BIT(12)
> +#define JZ_ADC_REG_ADCMD_VREFPXN	BIT(13)
> +#define JZ_ADC_REG_ADCMD_VREFPAUX	BIT(14)
> +#define JZ_ADC_REG_ADCMD_VREFPVDD33	BIT(15)
> +#define JZ_ADC_REG_ADCMD_VREFNYN	BIT(16)
> +#define JZ_ADC_REG_ADCMD_VREFNXP	BIT(17)
> +#define JZ_ADC_REG_ADCMD_VREFNXN	BIT(18)
> +#define JZ_ADC_REG_ADCMD_VREFAUX	BIT(19)
> +#define JZ_ADC_REG_ADCMD_YNGRU		BIT(20)
> +#define JZ_ADC_REG_ADCMD_XNGRU		BIT(21)
> +#define JZ_ADC_REG_ADCMD_XPGRU		BIT(22)
> +#define JZ_ADC_REG_ADCMD_YPSUP		BIT(23)
> +#define JZ_ADC_REG_ADCMD_XNSUP		BIT(24)
> +#define JZ_ADC_REG_ADCMD_XPSUP		BIT(25)
> +
>  #define JZ_ADC_AUX_VREF				3300
>  #define JZ_ADC_AUX_VREF_BITS			12
>  #define JZ_ADC_BATTERY_LOW_VREF			2500
> @@ -44,6 +73,14 @@
>  #define JZ4770_ADC_BATTERY_VREF			6600
>  #define JZ4770_ADC_BATTERY_VREF_BITS		12
>  
> +#define JZ_ADC_IRQ_AUX			BIT(0)
> +#define JZ_ADC_IRQ_BATTERY		BIT(1)
> +#define JZ_ADC_IRQ_TOUCH		BIT(2)
> +#define JZ_ADC_IRQ_PEN_DOWN		BIT(3)
> +#define JZ_ADC_IRQ_PEN_UP		BIT(4)
> +#define JZ_ADC_IRQ_PEN_DOWN_SLEEP	BIT(5)
> +#define JZ_ADC_IRQ_SLEEP		BIT(7)
> +
>  struct ingenic_adc;
>  
>  struct ingenic_adc_soc_data {
> @@ -69,6 +106,61 @@ struct ingenic_adc {
>  	bool low_vref_mode;
>  };
>  
> +static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, unsigned long mask)
> +{
> +	struct ingenic_adc *adc = iio_priv(iio_dev);
> +
> +	mutex_lock(&adc->lock);
> +
> +	/* Init ADCMD */
> +	readl(adc->base + JZ_ADC_REG_ADCMD);
> +
> +	if (mask & 0x3) {
> +		/* Second channel (INGENIC_ADC_TOUCH_YP): sample YP vs. GND */
> +		writel(JZ_ADC_REG_ADCMD_XNGRU
> +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_YPADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +
> +		/* First channel (INGENIC_ADC_TOUCH_XP): sample XP vs. GND */
> +		writel(JZ_ADC_REG_ADCMD_YNGRU
> +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_XPADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +	}
> +
> +	if (mask & 0xc) {
> +		/* Fourth channel (INGENIC_ADC_TOUCH_YN): sample YN vs. GND */
> +		writel(JZ_ADC_REG_ADCMD_XNGRU
> +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_YNADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +
> +		/* Third channel (INGENIC_ADC_TOUCH_XN): sample XN vs. GND */
> +		writel(JZ_ADC_REG_ADCMD_YNGRU
> +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_XNADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +	}
> +
> +	if (mask & 0x30) {
> +		/* Sixth channel (INGENIC_ADC_TOUCH_YD): sample YP vs. YN */
> +		writel(JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_YPADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +
> +		/* Fifth channel (INGENIC_ADC_TOUCH_XD): sample XP vs. XN */
> +		writel(JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> +		       | JZ_ADC_REG_ADCMD_XPADC,
> +		       adc->base + JZ_ADC_REG_ADCMD);
> +	}
> +
> +	/* We're done */
> +	writel(0, adc->base + JZ_ADC_REG_ADCMD);
> +
> +	mutex_unlock(&adc->lock);
> +}
> +
>  static void ingenic_adc_set_config(struct ingenic_adc *adc,
>  				   uint32_t mask,
>  				   uint32_t val)
> @@ -288,6 +380,72 @@ static const struct iio_chan_spec jz4740_channels[] = {
>  };
>  
>  static const struct iio_chan_spec jz4770_channels[] = {
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_XP,

Ah. sorry. I should have noticed this much earlier.

These aren't position channels as such.  They are channels
that are then processed into position in combination.  

Problem is I'm not sure how we 'should' describe then.

Perhaps this is the best we can do.

> +		.scan_index = 0,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_YP,
> +		.scan_index = 1,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_XN,
> +		.scan_index = 2,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_YN,
> +		.scan_index = 3,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_XD,
> +		.scan_index = 4,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
> +	{
> +		.type = IIO_POSITIONRELATIVE,
> +		.indexed = 1,
> +		.channel = INGENIC_ADC_TOUCH_YD,
> +		.scan_index = 5,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = 12,
> +			.storagebits = 16,
> +		},
> +	},
>  	{
>  		.extend_name = "aux",
>  		.type = IIO_VOLTAGE,
> @@ -490,13 +648,89 @@ static const struct iio_info ingenic_adc_info = {
>  	.of_xlate = ingenic_adc_of_xlate,
>  };
>  
> +static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev)
> +{
> +	struct ingenic_adc *adc = iio_priv(iio_dev);
> +	int ret;
> +
> +	ret = clk_enable(adc->clk);
> +	if (ret) {
> +		dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	/* It takes significant time for the touchscreen hw to stabilize. */
> +	msleep(50);
> +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK,
> +			       JZ_ADC_REG_CFG_SAMPLE_NUM(4) |
> +			       JZ_ADC_REG_CFG_PULL_UP(4));
> +
> +	writew(80, adc->base + JZ_ADC_REG_ADWAIT);
> +	writew(2, adc->base + JZ_ADC_REG_ADSAME);
> +	writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL);
> +	writel(0, adc->base + JZ_ADC_REG_ADTCH);
> +
> +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL,
> +			       JZ_ADC_REG_CFG_CMD_SEL);
> +	ingenic_adc_set_adcmd(iio_dev, iio_dev->active_scan_mask[0]);
> +
> +	ingenic_adc_enable(adc, 2, true);
> +
> +	return 0;
> +}
> +
> +static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev)
> +{
> +	struct ingenic_adc *adc = iio_priv(iio_dev);
> +
> +	ingenic_adc_enable(adc, 2, false);
> +
> +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL, 0);
> +
> +	writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
> +	writeb(0xff, adc->base + JZ_ADC_REG_STATUS);
> +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0);
> +	writew(0, adc->base + JZ_ADC_REG_ADSAME);
> +	writew(0, adc->base + JZ_ADC_REG_ADWAIT);
> +	clk_disable(adc->clk);
> +
> +	return 0;
> +}
> +
> +static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops = {
> +	.postenable = &ingenic_adc_buffer_enable,
> +	.predisable = &ingenic_adc_buffer_disable
> +};
> +
> +static irqreturn_t ingenic_adc_irq(int irq, void *data)
> +{
> +	struct iio_dev *iio_dev = data;
> +	struct ingenic_adc *adc = iio_priv(iio_dev);
> +	unsigned long mask = iio_dev->active_scan_mask[0];
> +	unsigned int i;
> +	u32 tdat[3];
> +
> +	for (i = 0; i < ARRAY_SIZE(tdat); mask >>= 2, i++) {
> +		if (mask & 0x3)
> +			tdat[i] = readl(adc->base + JZ_ADC_REG_ADTCH);
> +		else
> +			tdat[i] = 0;
> +	}
> +
> +	iio_push_to_buffers(iio_dev, tdat);
> +	writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS);
> +
> +	return IRQ_HANDLED;
> +}
> +
>  static int ingenic_adc_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct iio_dev *iio_dev;
>  	struct ingenic_adc *adc;
>  	const struct ingenic_adc_soc_data *soc_data;
> -	int ret;
> +	int irq, ret;
>  
>  	soc_data = device_get_match_data(dev);
>  	if (!soc_data)
> @@ -511,6 +745,17 @@ static int ingenic_adc_probe(struct platform_device *pdev)
>  	mutex_init(&adc->aux_lock);
>  	adc->soc_data = soc_data;
>  
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0,
> +			       dev_name(dev), iio_dev);
> +	if (ret < 0) {
> +		dev_err(dev, "Failed to request irq: %d\n", ret);
> +		return ret;
> +	}
> +
>  	adc->base = devm_platform_ioremap_resource(pdev, 0);
>  	if (IS_ERR(adc->base))
>  		return PTR_ERR(adc->base);
> @@ -550,7 +795,8 @@ static int ingenic_adc_probe(struct platform_device *pdev)
>  
>  	iio_dev->dev.parent = dev;
>  	iio_dev->name = "jz-adc";
> -	iio_dev->modes = INDIO_DIRECT_MODE;
> +	iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> +	iio_dev->setup_ops = &ingenic_buffer_setup_ops;
>  	iio_dev->channels = soc_data->channels;
>  	iio_dev->num_channels = soc_data->num_channels;
>  	iio_dev->info = &ingenic_adc_info;

Artur Rojek July 12, 2020, 7:53 p.m. UTC | #9

On 2020-07-12 14:11, Jonathan Cameron wrote:
> On Sun, 12 Jul 2020 13:07:13 +0100
> Jonathan Cameron <jic23@kernel.org> wrote:
> 
>> On Thu,  9 Jul 2020 17:21:58 +0200
>> Artur Rojek <contact@artur-rojek.eu> wrote:
>> 
>> > From: Paul Cercueil <paul@crapouillou.net>
>> >
>> > Instead of having one array of struct iio_chan_spec for all SoCs, and
>> > have some SoCs remove the last item of the array as they can't use it,
>> > have each SoC define its array of supported channels.
>> >
>> > Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>> > Tested-by: Artur Rojek <contact@artur-rojek.eu>
>> Applied to the togreg branch of iio.git and pushed out as testing for
>> autobuilders to play with it.
> Actually removed from tree again.
> 
> Artur, as you sent this patch on to me, you need to sign-off on it
> so we maintain the DCO related records of how this got to the kernel.
> You can just reply here to give it.

Signed-off-by: Artur Rojek <contact@artur-rojek.eu>

Thanks,
Artur

> 
> Thanks,
> 
> Jonathan
> 
>> 
>> Thanks,
>> 
>> Jonathan
>> 
>> > ---
>> >
>> >  Changes:
>> >
>> >  v8: new patch
>> >
>> >  drivers/iio/adc/ingenic-adc.c | 99 +++++++++++++++++++++++------------
>> >  1 file changed, 65 insertions(+), 34 deletions(-)
>> >
>> > diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-adc.c
>> > index 89019fb59d48..0233a9055c86 100644
>> > --- a/drivers/iio/adc/ingenic-adc.c
>> > +++ b/drivers/iio/adc/ingenic-adc.c
>> > @@ -55,6 +55,8 @@ struct ingenic_adc_soc_data {
>> >  	size_t battery_scale_avail_size;
>> >  	unsigned int battery_vref_mode: 1;
>> >  	unsigned int has_aux2: 1;
>> > +	const struct iio_chan_spec *channels;
>> > +	unsigned int num_channels;
>> >  	int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
>> >  };
>> >
>> > @@ -262,6 +264,61 @@ static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
>> >  	return 0;
>> >  }
>> >
>> > +static const struct iio_chan_spec jz4740_channels[] = {
>> > +	{
>> > +		.extend_name = "aux",
>> > +		.type = IIO_VOLTAGE,
>> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > +				      BIT(IIO_CHAN_INFO_SCALE),
>> > +		.indexed = 1,
>> > +		.channel = INGENIC_ADC_AUX,
>> > +		.scan_index = -1,
>> > +	},
>> > +	{
>> > +		.extend_name = "battery",
>> > +		.type = IIO_VOLTAGE,
>> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > +				      BIT(IIO_CHAN_INFO_SCALE),
>> > +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
>> > +						BIT(IIO_CHAN_INFO_SCALE),
>> > +		.indexed = 1,
>> > +		.channel = INGENIC_ADC_BATTERY,
>> > +		.scan_index = -1,
>> > +	},
>> > +};
>> > +
>> > +static const struct iio_chan_spec jz4770_channels[] = {
>> > +	{
>> > +		.extend_name = "aux",
>> > +		.type = IIO_VOLTAGE,
>> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > +				      BIT(IIO_CHAN_INFO_SCALE),
>> > +		.indexed = 1,
>> > +		.channel = INGENIC_ADC_AUX,
>> > +		.scan_index = -1,
>> > +	},
>> > +	{
>> > +		.extend_name = "battery",
>> > +		.type = IIO_VOLTAGE,
>> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > +				      BIT(IIO_CHAN_INFO_SCALE),
>> > +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
>> > +						BIT(IIO_CHAN_INFO_SCALE),
>> > +		.indexed = 1,
>> > +		.channel = INGENIC_ADC_BATTERY,
>> > +		.scan_index = -1,
>> > +	},
>> > +	{
>> > +		.extend_name = "aux2",
>> > +		.type = IIO_VOLTAGE,
>> > +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > +				      BIT(IIO_CHAN_INFO_SCALE),
>> > +		.indexed = 1,
>> > +		.channel = INGENIC_ADC_AUX2,
>> > +		.scan_index = -1,
>> > +	},
>> > +};
>> > +
>> >  static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
>> >  	.battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF,
>> >  	.battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
>> > @@ -271,6 +328,8 @@ static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
>> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail),
>> >  	.battery_vref_mode = true,
>> >  	.has_aux2 = false,
>> > +	.channels = jz4740_channels,
>> > +	.num_channels = ARRAY_SIZE(jz4740_channels),
>> >  	.init_clk_div = jz4725b_adc_init_clk_div,
>> >  };
>> >
>> > @@ -283,6 +342,8 @@ static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
>> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail),
>> >  	.battery_vref_mode = true,
>> >  	.has_aux2 = false,
>> > +	.channels = jz4740_channels,
>> > +	.num_channels = ARRAY_SIZE(jz4740_channels),
>> >  	.init_clk_div = NULL, /* no ADCLK register on JZ4740 */
>> >  };
>> >
>> > @@ -295,6 +356,8 @@ static const struct ingenic_adc_soc_data jz4770_adc_soc_data = {
>> >  	.battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail),
>> >  	.battery_vref_mode = false,
>> >  	.has_aux2 = true,
>> > +	.channels = jz4770_channels,
>> > +	.num_channels = ARRAY_SIZE(jz4770_channels),
>> >  	.init_clk_div = jz4770_adc_init_clk_div,
>> >  };
>> >
>> > @@ -427,35 +490,6 @@ static const struct iio_info ingenic_adc_info = {
>> >  	.of_xlate = ingenic_adc_of_xlate,
>> >  };
>> >
>> > -static const struct iio_chan_spec ingenic_channels[] = {
>> > -	{
>> > -		.extend_name = "aux",
>> > -		.type = IIO_VOLTAGE,
>> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > -				      BIT(IIO_CHAN_INFO_SCALE),
>> > -		.indexed = 1,
>> > -		.channel = INGENIC_ADC_AUX,
>> > -	},
>> > -	{
>> > -		.extend_name = "battery",
>> > -		.type = IIO_VOLTAGE,
>> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > -				      BIT(IIO_CHAN_INFO_SCALE),
>> > -		.info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
>> > -						BIT(IIO_CHAN_INFO_SCALE),
>> > -		.indexed = 1,
>> > -		.channel = INGENIC_ADC_BATTERY,
>> > -	},
>> > -	{ /* Must always be last in the array. */
>> > -		.extend_name = "aux2",
>> > -		.type = IIO_VOLTAGE,
>> > -		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> > -				      BIT(IIO_CHAN_INFO_SCALE),
>> > -		.indexed = 1,
>> > -		.channel = INGENIC_ADC_AUX2,
>> > -	},
>> > -};
>> > -
>> >  static int ingenic_adc_probe(struct platform_device *pdev)
>> >  {
>> >  	struct device *dev = &pdev->dev;
>> > @@ -517,11 +551,8 @@ static int ingenic_adc_probe(struct platform_device *pdev)
>> >  	iio_dev->dev.parent = dev;
>> >  	iio_dev->name = "jz-adc";
>> >  	iio_dev->modes = INDIO_DIRECT_MODE;
>> > -	iio_dev->channels = ingenic_channels;
>> > -	iio_dev->num_channels = ARRAY_SIZE(ingenic_channels);
>> > -	/* Remove AUX2 from the list of supported channels. */
>> > -	if (!adc->soc_data->has_aux2)
>> > -		iio_dev->num_channels -= 1;
>> > +	iio_dev->channels = soc_data->channels;
>> > +	iio_dev->num_channels = soc_data->num_channels;
>> >  	iio_dev->info = &ingenic_adc_info;
>> >
>> >  	ret = devm_iio_device_register(dev, iio_dev);
>>

Paul Cercueil July 12, 2020, 8:16 p.m. UTC | #10

Hi Jonathan,

Le dim. 12 juil. 2020 à 14:19, Jonathan Cameron <jic23@kernel.org> a 
écrit :
> On Thu,  9 Jul 2020 17:22:00 +0200
> Artur Rojek <contact@artur-rojek.eu> wrote:
> 
>>  The SADC component in JZ47xx SoCs provides support for touchscreen
>>  operations (pen position and pen down pressure) in single-ended and
>>  differential modes.
>> 
>>  The touchscreen component of SADC takes a significant time to 
>> stabilize
>>  after first receiving the clock and a delay of 50ms has been 
>> empirically
>>  proven to be a safe value before data sampling can begin.
>> 
>>  Of the known hardware to use this controller, GCW Zero and Anbernic 
>> RG-350
>>  utilize the touchscreen mode by having their joystick(s) attached 
>> to the
>>  X/Y positive/negative input pins.
>> 
>>  JZ4770 and later SoCs introduce a low-level command feature. With 
>> it, up
>>  to 32 commands can be programmed, each one corresponding to a 
>> sampling
>>  job. It allows to change the low-voltage reference, the high-voltage
>>  reference, have them connected to VCC, GND, or one of the X-/X+ or 
>> Y-/Y+
>>  pins.
>> 
>>  This patch introduces support for 6 stream-capable channels:
>>  - channel #0 samples X+/GND
>>  - channel #1 samples Y+/GND
>>  - channel #2 samples X-/GND
>>  - channel #3 samples Y-/GND
>>  - channel #4 samples X+/X-
>>  - channel #5 samples Y+/Y-
> 
> The one thing I noticed on this read was that we are slightly 
> stretching
> the normal IIO channel definitions.  The claim is that each of these 
> channels
> is a POSITIONREALTIVE channel, whereas that isn't really true.  They 
> are
> related to the position, but as I understand it not directly 
> measuring it
> (particularly X+ - X-) which is pretty much a reference voltage (I 
> think!)
> 
> We might be better off just describing these as voltage channels, with
> 4 and 5 described as differential voltage channels.  The problem there
> being that it doesn't describe the fact that the measurements are with
> particular voltages also being applied to the touch screen.
> 
> Perhaps we are best off just leaving it as you have it and being a bit
> 'odd'.  What do you think?  Having written this down I think perhaps 
> leaving
> it alone is the best plan :(

That's up to you really. These ADC channels will measure voltage, but 
they are supposed to be used with a touchscreen, that's why we went 
with POSITIONRELATIVE. However, with the kind of devices we're working 
with, they are never used as such, so using VOLTAGE would work too.

> Otherwise this all looks fine to me.
> 
> Thanks,
> 
> Jonathan
> 
>> 
>>  Being able to sample X-/GND and Y-/GND is useful on some devices, 
>> where
>>  one joystick is connected to the X+/Y+ pins, and a second joystick 
>> is
>>  connected to the X-/Y- pins.
>> 
>>  All the boards which probe this driver have the interrupt provided 
>> from
>>  Device Tree, with no need to handle a case where the IRQ was not 
>> provided.
>> 
>>  Co-developed-by: Paul Cercueil <paul@crapouillou.net>
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
>>  ---
>> 
>>   Changes:
>> 
>>   v2: - improve description of the touchscreen mode,
>>       - get rid of the unneeded kfifo,
>>       - drop IIO_BUFFER_CB from Kconfig,
>>       - remove extended names from the touchscreen channels
>> 
>>   v3: remove unneeded `linux/iio/kfifo_buf.h` include
>> 
>>   v4: clarify irq provider source in the patch description
>> 
>>   v5: no change
>> 
>>   v6: - correct the spelling of Device Tree and IRQ in commit message
>>       - don't omit trailing commas from initializer lists
>>       - error check `clk_enable`
>>       - remove redundant `dev_err` from `platform_get_irq` error 
>> check
>> 
>>   v7: no change
>> 
>>   v8: add support for ADCMD low-level command feature
>> 
>>   drivers/iio/adc/Kconfig       |   1 +
>>   drivers/iio/adc/ingenic-adc.c | 250 
>> +++++++++++++++++++++++++++++++++-
>>   2 files changed, 249 insertions(+), 2 deletions(-)
>> 
>>  diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
>>  index ff3569635ce0..5b57437cef75 100644
>>  --- a/drivers/iio/adc/Kconfig
>>  +++ b/drivers/iio/adc/Kconfig
>>  @@ -500,6 +500,7 @@ config INA2XX_ADC
>>   config INGENIC_ADC
>>   	tristate "Ingenic JZ47xx SoCs ADC driver"
>>   	depends on MIPS || COMPILE_TEST
>>  +	select IIO_BUFFER
>>   	help
>>   	  Say yes here to build support for the Ingenic JZ47xx SoCs ADC 
>> unit.
>> 
>>  diff --git a/drivers/iio/adc/ingenic-adc.c 
>> b/drivers/iio/adc/ingenic-adc.c
>>  index 0233a9055c86..976aea46fede 100644
>>  --- a/drivers/iio/adc/ingenic-adc.c
>>  +++ b/drivers/iio/adc/ingenic-adc.c
>>  @@ -8,7 +8,9 @@
>> 
>>   #include <dt-bindings/iio/adc/ingenic,adc.h>
>>   #include <linux/clk.h>
>>  +#include <linux/iio/buffer.h>
>>   #include <linux/iio/iio.h>
>>  +#include <linux/interrupt.h>
>>   #include <linux/io.h>
>>   #include <linux/iopoll.h>
>>   #include <linux/kernel.h>
>>  @@ -20,19 +22,46 @@
>>   #define JZ_ADC_REG_CFG			0x04
>>   #define JZ_ADC_REG_CTRL			0x08
>>   #define JZ_ADC_REG_STATUS		0x0c
>>  +#define JZ_ADC_REG_ADSAME		0x10
>>  +#define JZ_ADC_REG_ADWAIT		0x14
>>   #define JZ_ADC_REG_ADTCH		0x18
>>   #define JZ_ADC_REG_ADBDAT		0x1c
>>   #define JZ_ADC_REG_ADSDAT		0x20
>>  +#define JZ_ADC_REG_ADCMD		0x24
>>   #define JZ_ADC_REG_ADCLK		0x28
>> 
>>   #define JZ_ADC_REG_ENABLE_PD		BIT(7)
>>   #define JZ_ADC_REG_CFG_AUX_MD		(BIT(0) | BIT(1))
>>   #define JZ_ADC_REG_CFG_BAT_MD		BIT(4)
>>  +#define JZ_ADC_REG_CFG_SAMPLE_NUM(n)	((n) << 10)
>>  +#define JZ_ADC_REG_CFG_PULL_UP(n)	((n) << 16)
>>  +#define JZ_ADC_REG_CFG_CMD_SEL		BIT(22)
>>  +#define JZ_ADC_REG_CFG_TOUCH_OPS_MASK	(BIT(31) | GENMASK(23, 10))
>>   #define JZ_ADC_REG_ADCLK_CLKDIV_LSB	0
>>   #define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB	16
>>   #define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB	8
>>   #define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB	16
>> 
>>  +#define JZ_ADC_REG_ADCMD_YNADC		BIT(7)
>>  +#define JZ_ADC_REG_ADCMD_YPADC		BIT(8)
>>  +#define JZ_ADC_REG_ADCMD_XNADC		BIT(9)
>>  +#define JZ_ADC_REG_ADCMD_XPADC		BIT(10)
>>  +#define JZ_ADC_REG_ADCMD_VREFPYP	BIT(11)
>>  +#define JZ_ADC_REG_ADCMD_VREFPXP	BIT(12)
>>  +#define JZ_ADC_REG_ADCMD_VREFPXN	BIT(13)
>>  +#define JZ_ADC_REG_ADCMD_VREFPAUX	BIT(14)
>>  +#define JZ_ADC_REG_ADCMD_VREFPVDD33	BIT(15)
>>  +#define JZ_ADC_REG_ADCMD_VREFNYN	BIT(16)
>>  +#define JZ_ADC_REG_ADCMD_VREFNXP	BIT(17)
>>  +#define JZ_ADC_REG_ADCMD_VREFNXN	BIT(18)
>>  +#define JZ_ADC_REG_ADCMD_VREFAUX	BIT(19)
>>  +#define JZ_ADC_REG_ADCMD_YNGRU		BIT(20)
>>  +#define JZ_ADC_REG_ADCMD_XNGRU		BIT(21)
>>  +#define JZ_ADC_REG_ADCMD_XPGRU		BIT(22)
>>  +#define JZ_ADC_REG_ADCMD_YPSUP		BIT(23)
>>  +#define JZ_ADC_REG_ADCMD_XNSUP		BIT(24)
>>  +#define JZ_ADC_REG_ADCMD_XPSUP		BIT(25)
>>  +
>>   #define JZ_ADC_AUX_VREF				3300
>>   #define JZ_ADC_AUX_VREF_BITS			12
>>   #define JZ_ADC_BATTERY_LOW_VREF			2500
>>  @@ -44,6 +73,14 @@
>>   #define JZ4770_ADC_BATTERY_VREF			6600
>>   #define JZ4770_ADC_BATTERY_VREF_BITS		12
>> 
>>  +#define JZ_ADC_IRQ_AUX			BIT(0)
>>  +#define JZ_ADC_IRQ_BATTERY		BIT(1)
>>  +#define JZ_ADC_IRQ_TOUCH		BIT(2)
>>  +#define JZ_ADC_IRQ_PEN_DOWN		BIT(3)
>>  +#define JZ_ADC_IRQ_PEN_UP		BIT(4)
>>  +#define JZ_ADC_IRQ_PEN_DOWN_SLEEP	BIT(5)
>>  +#define JZ_ADC_IRQ_SLEEP		BIT(7)
>>  +
>>   struct ingenic_adc;
>> 
>>   struct ingenic_adc_soc_data {
>>  @@ -69,6 +106,61 @@ struct ingenic_adc {
>>   	bool low_vref_mode;
>>   };
>> 
>>  +static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, 
>> unsigned long mask)
>>  +{
>>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
>>  +
>>  +	mutex_lock(&adc->lock);
>>  +
>>  +	/* Init ADCMD */
>>  +	readl(adc->base + JZ_ADC_REG_ADCMD);
>>  +
>>  +	if (mask & 0x3) {
>>  +		/* Second channel (INGENIC_ADC_TOUCH_YP): sample YP vs. GND */
>>  +		writel(JZ_ADC_REG_ADCMD_XNGRU
>>  +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_YPADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +
>>  +		/* First channel (INGENIC_ADC_TOUCH_XP): sample XP vs. GND */
>>  +		writel(JZ_ADC_REG_ADCMD_YNGRU
>>  +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_XPADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +	}
>>  +
>>  +	if (mask & 0xc) {
>>  +		/* Fourth channel (INGENIC_ADC_TOUCH_YN): sample YN vs. GND */
>>  +		writel(JZ_ADC_REG_ADCMD_XNGRU
>>  +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_YNADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +
>>  +		/* Third channel (INGENIC_ADC_TOUCH_XN): sample XN vs. GND */
>>  +		writel(JZ_ADC_REG_ADCMD_YNGRU
>>  +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_XNADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +	}
>>  +
>>  +	if (mask & 0x30) {
>>  +		/* Sixth channel (INGENIC_ADC_TOUCH_YD): sample YP vs. YN */
>>  +		writel(JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_YPADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +
>>  +		/* Fifth channel (INGENIC_ADC_TOUCH_XD): sample XP vs. XN */
>>  +		writel(JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
>>  +		       | JZ_ADC_REG_ADCMD_XPADC,
>>  +		       adc->base + JZ_ADC_REG_ADCMD);
>>  +	}
>>  +
>>  +	/* We're done */
>>  +	writel(0, adc->base + JZ_ADC_REG_ADCMD);
>>  +
>>  +	mutex_unlock(&adc->lock);
>>  +}
>>  +
>>   static void ingenic_adc_set_config(struct ingenic_adc *adc,
>>   				   uint32_t mask,
>>   				   uint32_t val)
>>  @@ -288,6 +380,72 @@ static const struct iio_chan_spec 
>> jz4740_channels[] = {
>>   };
>> 
>>   static const struct iio_chan_spec jz4770_channels[] = {
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_XP,
> 
> Ah. sorry. I should have noticed this much earlier.
> 
> These aren't position channels as such.  They are channels
> that are then processed into position in combination.
> 
> Problem is I'm not sure how we 'should' describe then.
> 
> Perhaps this is the best we can do.

We could have the two differencial channels as IIO_POSITIONRELATIVE, 
and the four single-ended ones as IIO_VOLTAGE.

Cheers,
-Paul

>>  +		.scan_index = 0,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_YP,
>>  +		.scan_index = 1,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_XN,
>>  +		.scan_index = 2,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_YN,
>>  +		.scan_index = 3,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_XD,
>>  +		.scan_index = 4,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>  +	{
>>  +		.type = IIO_POSITIONRELATIVE,
>>  +		.indexed = 1,
>>  +		.channel = INGENIC_ADC_TOUCH_YD,
>>  +		.scan_index = 5,
>>  +		.scan_type = {
>>  +			.sign = 'u',
>>  +			.realbits = 12,
>>  +			.storagebits = 16,
>>  +		},
>>  +	},
>>   	{
>>   		.extend_name = "aux",
>>   		.type = IIO_VOLTAGE,
>>  @@ -490,13 +648,89 @@ static const struct iio_info ingenic_adc_info 
>> = {
>>   	.of_xlate = ingenic_adc_of_xlate,
>>   };
>> 
>>  +static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev)
>>  +{
>>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
>>  +	int ret;
>>  +
>>  +	ret = clk_enable(adc->clk);
>>  +	if (ret) {
>>  +		dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
>>  +			ret);
>>  +		return ret;
>>  +	}
>>  +
>>  +	/* It takes significant time for the touchscreen hw to stabilize. 
>> */
>>  +	msleep(50);
>>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK,
>>  +			       JZ_ADC_REG_CFG_SAMPLE_NUM(4) |
>>  +			       JZ_ADC_REG_CFG_PULL_UP(4));
>>  +
>>  +	writew(80, adc->base + JZ_ADC_REG_ADWAIT);
>>  +	writew(2, adc->base + JZ_ADC_REG_ADSAME);
>>  +	writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL);
>>  +	writel(0, adc->base + JZ_ADC_REG_ADTCH);
>>  +
>>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL,
>>  +			       JZ_ADC_REG_CFG_CMD_SEL);
>>  +	ingenic_adc_set_adcmd(iio_dev, iio_dev->active_scan_mask[0]);
>>  +
>>  +	ingenic_adc_enable(adc, 2, true);
>>  +
>>  +	return 0;
>>  +}
>>  +
>>  +static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev)
>>  +{
>>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
>>  +
>>  +	ingenic_adc_enable(adc, 2, false);
>>  +
>>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL, 0);
>>  +
>>  +	writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
>>  +	writeb(0xff, adc->base + JZ_ADC_REG_STATUS);
>>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0);
>>  +	writew(0, adc->base + JZ_ADC_REG_ADSAME);
>>  +	writew(0, adc->base + JZ_ADC_REG_ADWAIT);
>>  +	clk_disable(adc->clk);
>>  +
>>  +	return 0;
>>  +}
>>  +
>>  +static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops 
>> = {
>>  +	.postenable = &ingenic_adc_buffer_enable,
>>  +	.predisable = &ingenic_adc_buffer_disable
>>  +};
>>  +
>>  +static irqreturn_t ingenic_adc_irq(int irq, void *data)
>>  +{
>>  +	struct iio_dev *iio_dev = data;
>>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
>>  +	unsigned long mask = iio_dev->active_scan_mask[0];
>>  +	unsigned int i;
>>  +	u32 tdat[3];
>>  +
>>  +	for (i = 0; i < ARRAY_SIZE(tdat); mask >>= 2, i++) {
>>  +		if (mask & 0x3)
>>  +			tdat[i] = readl(adc->base + JZ_ADC_REG_ADTCH);
>>  +		else
>>  +			tdat[i] = 0;
>>  +	}
>>  +
>>  +	iio_push_to_buffers(iio_dev, tdat);
>>  +	writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS);
>>  +
>>  +	return IRQ_HANDLED;
>>  +}
>>  +
>>   static int ingenic_adc_probe(struct platform_device *pdev)
>>   {
>>   	struct device *dev = &pdev->dev;
>>   	struct iio_dev *iio_dev;
>>   	struct ingenic_adc *adc;
>>   	const struct ingenic_adc_soc_data *soc_data;
>>  -	int ret;
>>  +	int irq, ret;
>> 
>>   	soc_data = device_get_match_data(dev);
>>   	if (!soc_data)
>>  @@ -511,6 +745,17 @@ static int ingenic_adc_probe(struct 
>> platform_device *pdev)
>>   	mutex_init(&adc->aux_lock);
>>   	adc->soc_data = soc_data;
>> 
>>  +	irq = platform_get_irq(pdev, 0);
>>  +	if (irq < 0)
>>  +		return irq;
>>  +
>>  +	ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0,
>>  +			       dev_name(dev), iio_dev);
>>  +	if (ret < 0) {
>>  +		dev_err(dev, "Failed to request irq: %d\n", ret);
>>  +		return ret;
>>  +	}
>>  +
>>   	adc->base = devm_platform_ioremap_resource(pdev, 0);
>>   	if (IS_ERR(adc->base))
>>   		return PTR_ERR(adc->base);
>>  @@ -550,7 +795,8 @@ static int ingenic_adc_probe(struct 
>> platform_device *pdev)
>> 
>>   	iio_dev->dev.parent = dev;
>>   	iio_dev->name = "jz-adc";
>>  -	iio_dev->modes = INDIO_DIRECT_MODE;
>>  +	iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
>>  +	iio_dev->setup_ops = &ingenic_buffer_setup_ops;
>>   	iio_dev->channels = soc_data->channels;
>>   	iio_dev->num_channels = soc_data->num_channels;
>>   	iio_dev->info = &ingenic_adc_info;
>

Alexandru Ardelean July 13, 2020, 5:07 a.m. UTC | #11

On Sun, 2020-07-12 at 13:02 +0100, Jonathan Cameron wrote:
> On Thu,  9 Jul 2020 17:21:56 +0200
> Artur Rojek <contact@artur-rojek.eu> wrote:
> 
> > Introduce error checks for the clk_enable calls used in this driver.
> > As part of the changes, move clk_enable/clk_disable calls out of
> > ingenic_adc_set_config and into respective logic of its callers.
> > 
> > Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> > Tested-by: Paul Cercueil <paul@crapouillou.net>
> Applied.
> 
> Thanks,
> 
> Jonathan
> 
> > ---
> > 
> >  Changes:
> > 
> >  v6: new patch
> > 
> >  v7: no change
> > 
> >  v8: move `clk_disable` outside the lock
> > 
> >  drivers/iio/adc/ingenic-adc.c | 25 +++++++++++++++++++++----
> >  1 file changed, 21 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-
> > adc.c
> > index 39c0a609fc94..c1946a9f1cca 100644
> > --- a/drivers/iio/adc/ingenic-adc.c
> > +++ b/drivers/iio/adc/ingenic-adc.c
> > @@ -73,7 +73,6 @@ static void ingenic_adc_set_config(struct ingenic_adc
> > *adc,
> >  {
> >  	uint32_t cfg;
> >  
> > -	clk_enable(adc->clk);
> >  	mutex_lock(&adc->lock);
> >  
> >  	cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
> > @@ -81,7 +80,6 @@ static void ingenic_adc_set_config(struct ingenic_adc
> > *adc,
> >  	writel(cfg, adc->base + JZ_ADC_REG_CFG);
> >  
> >  	mutex_unlock(&adc->lock);
> > -	clk_disable(adc->clk);
> >  }
> >  
> >  static void ingenic_adc_enable(struct ingenic_adc *adc,
> > @@ -124,6 +122,8 @@ static int ingenic_adc_write_raw(struct iio_dev
> > *iio_dev,
> >  				 long m)
> >  {
> >  	struct ingenic_adc *adc = iio_priv(iio_dev);
> > +	struct device *dev = iio_dev->dev.parent;
> > +	int ret;
> >  
> >  	switch (m) {
> >  	case IIO_CHAN_INFO_SCALE:
> > @@ -131,6 +131,14 @@ static int ingenic_adc_write_raw(struct iio_dev
> > *iio_dev,
> >  		case INGENIC_ADC_BATTERY:
> >  			if (!adc->soc_data->battery_vref_mode)
> >  				return -EINVAL;
> > +
> > +			ret = clk_enable(adc->clk);
> > +			if (ret) {
> > +				dev_err(dev, "Failed to enable clock:
> > %d\n",
> > +					ret);
> > +				return ret;
> > +			}
> > +
> >  			if (val > JZ_ADC_BATTERY_LOW_VREF) {
> >  				ingenic_adc_set_config(adc,
> >  						       JZ_ADC_REG_CFG_BAT_M
> > D,
> > @@ -142,6 +150,9 @@ static int ingenic_adc_write_raw(struct iio_dev
> > *iio_dev,
> >  						       JZ_ADC_REG_CFG_BAT_M
> > D);
> >  				adc->low_vref_mode = true;
> >  			}
> > +
> > +			clk_disable(adc->clk);
> > +
> >  			return 0;
> >  		default:
> >  			return -EINVAL;
> > @@ -317,6 +328,13 @@ static int ingenic_adc_read_chan_info_raw(struct
> > ingenic_adc *adc,
> >  					  int *val)
> >  {
> >  	int bit, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
> > +	struct device *dev = iio_priv_to_dev(adc)->dev.parent;

This uses iio_priv_to_dev(), which should be removed [if it hasn't been
already].
Also, with the iio_dev_opaque struct/type, using the iio_priv_to_dev()
helper shouldn't work, or should give undefined behavior, as the offset to
the private data should be matched against iio_dev_opaque (and not
iio_dev).

Looking at this code, it looks like ingenic_adc_read_chan_info_raw() can
take an 'indio_dev' reference and obtain the private information via
iio_priv()

Maybe [for some] there's a question as to why iio_priv_to_dev() is being
removed.
The answer is: because the iio_dev_opaque struct/type was introduced to
hide some iio_dev [INTERN] fields; the main reason for hiding them [aside
from good coding practice, and because they belong to the IIO framework] is
to not have to review new drivers being copied/adapted from old drivers.

Naturally, the iio_priv_to_dev() could have been kept around [in a reworked
form], but it didn't make much sense, since most users of iio_priv_to_dev()
could access a reference to indio_dev without much/any hassle.

> > +
> > +	ret = clk_enable(adc->clk);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to enable clock: %d\n", ret);
> > +		return ret;
> > +	}
> >  
> >  	/* We cannot sample AUX/AUX2 in parallel. */
> >  	mutex_lock(&adc->aux_lock);
> > @@ -325,7 +343,6 @@ static int ingenic_adc_read_chan_info_raw(struct
> > ingenic_adc *adc,
> >  		ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, bit);
> >  	}
> >  
> > -	clk_enable(adc->clk);
> >  	ret = ingenic_adc_capture(adc, engine);
> >  	if (ret)
> >  		goto out;
> > @@ -342,8 +359,8 @@ static int ingenic_adc_read_chan_info_raw(struct
> > ingenic_adc *adc,
> >  
> >  	ret = IIO_VAL_INT;
> >  out:
> > -	clk_disable(adc->clk);
> >  	mutex_unlock(&adc->aux_lock);
> > +	clk_disable(adc->clk);
> >  
> >  	return ret;
> >  }

Jonathan Cameron July 13, 2020, 11:20 a.m. UTC | #12

On Mon, 13 Jul 2020 05:07:44 +0000
"Ardelean, Alexandru" <alexandru.Ardelean@analog.com> wrote:

> On Sun, 2020-07-12 at 13:02 +0100, Jonathan Cameron wrote:
> > On Thu,  9 Jul 2020 17:21:56 +0200
> > Artur Rojek <contact@artur-rojek.eu> wrote:
> >   
> > > Introduce error checks for the clk_enable calls used in this driver.
> > > As part of the changes, move clk_enable/clk_disable calls out of
> > > ingenic_adc_set_config and into respective logic of its callers.
> > > 
> > > Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> > > Tested-by: Paul Cercueil <paul@crapouillou.net>  
> > Applied.
> > 
> > Thanks,
> > 
> > Jonathan
> >   
> > > ---
> > > 
> > >  Changes:
> > > 
> > >  v6: new patch
> > > 
> > >  v7: no change
> > > 
> > >  v8: move `clk_disable` outside the lock
> > > 
> > >  drivers/iio/adc/ingenic-adc.c | 25 +++++++++++++++++++++----
> > >  1 file changed, 21 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/iio/adc/ingenic-adc.c b/drivers/iio/adc/ingenic-
> > > adc.c
> > > index 39c0a609fc94..c1946a9f1cca 100644
> > > --- a/drivers/iio/adc/ingenic-adc.c
> > > +++ b/drivers/iio/adc/ingenic-adc.c
> > > @@ -73,7 +73,6 @@ static void ingenic_adc_set_config(struct ingenic_adc
> > > *adc,
> > >  {
> > >  	uint32_t cfg;
> > >  
> > > -	clk_enable(adc->clk);
> > >  	mutex_lock(&adc->lock);
> > >  
> > >  	cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
> > > @@ -81,7 +80,6 @@ static void ingenic_adc_set_config(struct ingenic_adc
> > > *adc,
> > >  	writel(cfg, adc->base + JZ_ADC_REG_CFG);
> > >  
> > >  	mutex_unlock(&adc->lock);
> > > -	clk_disable(adc->clk);
> > >  }
> > >  
> > >  static void ingenic_adc_enable(struct ingenic_adc *adc,
> > > @@ -124,6 +122,8 @@ static int ingenic_adc_write_raw(struct iio_dev
> > > *iio_dev,
> > >  				 long m)
> > >  {
> > >  	struct ingenic_adc *adc = iio_priv(iio_dev);
> > > +	struct device *dev = iio_dev->dev.parent;
> > > +	int ret;
> > >  
> > >  	switch (m) {
> > >  	case IIO_CHAN_INFO_SCALE:
> > > @@ -131,6 +131,14 @@ static int ingenic_adc_write_raw(struct iio_dev
> > > *iio_dev,
> > >  		case INGENIC_ADC_BATTERY:
> > >  			if (!adc->soc_data->battery_vref_mode)
> > >  				return -EINVAL;
> > > +
> > > +			ret = clk_enable(adc->clk);
> > > +			if (ret) {
> > > +				dev_err(dev, "Failed to enable clock:
> > > %d\n",
> > > +					ret);
> > > +				return ret;
> > > +			}
> > > +
> > >  			if (val > JZ_ADC_BATTERY_LOW_VREF) {
> > >  				ingenic_adc_set_config(adc,
> > >  						       JZ_ADC_REG_CFG_BAT_M
> > > D,
> > > @@ -142,6 +150,9 @@ static int ingenic_adc_write_raw(struct iio_dev
> > > *iio_dev,
> > >  						       JZ_ADC_REG_CFG_BAT_M
> > > D);
> > >  				adc->low_vref_mode = true;
> > >  			}
> > > +
> > > +			clk_disable(adc->clk);
> > > +
> > >  			return 0;
> > >  		default:
> > >  			return -EINVAL;
> > > @@ -317,6 +328,13 @@ static int ingenic_adc_read_chan_info_raw(struct
> > > ingenic_adc *adc,
> > >  					  int *val)
> > >  {
> > >  	int bit, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
> > > +	struct device *dev = iio_priv_to_dev(adc)->dev.parent;  
> 
> This uses iio_priv_to_dev(), which should be removed [if it hasn't been
> already].

Gah I missed that. 
For now best bet is probably if I drop this series from here on until we have
this tidied up in a v9.  Its my fault as I messed up and lost one patch in
the middle of Alex's series somehow, hence it is still there but broken in
the tree.

Thanks.

Jonathan

> Also, with the iio_dev_opaque struct/type, using the iio_priv_to_dev()
> helper shouldn't work, or should give undefined behavior, as the offset to
> the private data should be matched against iio_dev_opaque (and not
> iio_dev).
> 
> Looking at this code, it looks like ingenic_adc_read_chan_info_raw() can
> take an 'indio_dev' reference and obtain the private information via
> iio_priv()
> 
> Maybe [for some] there's a question as to why iio_priv_to_dev() is being
> removed.
> The answer is: because the iio_dev_opaque struct/type was introduced to
> hide some iio_dev [INTERN] fields; the main reason for hiding them [aside
> from good coding practice, and because they belong to the IIO framework] is
> to not have to review new drivers being copied/adapted from old drivers.
> 
> Naturally, the iio_priv_to_dev() could have been kept around [in a reworked
> form], but it didn't make much sense, since most users of iio_priv_to_dev()
> could access a reference to indio_dev without much/any hassle.
> 
> > > +
> > > +	ret = clk_enable(adc->clk);
> > > +	if (ret) {
> > > +		dev_err(dev, "Failed to enable clock: %d\n", ret);
> > > +		return ret;
> > > +	}
> > >  
> > >  	/* We cannot sample AUX/AUX2 in parallel. */
> > >  	mutex_lock(&adc->aux_lock);
> > > @@ -325,7 +343,6 @@ static int ingenic_adc_read_chan_info_raw(struct
> > > ingenic_adc *adc,
> > >  		ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, bit);
> > >  	}
> > >  
> > > -	clk_enable(adc->clk);
> > >  	ret = ingenic_adc_capture(adc, engine);
> > >  	if (ret)
> > >  		goto out;
> > > @@ -342,8 +359,8 @@ static int ingenic_adc_read_chan_info_raw(struct
> > > ingenic_adc *adc,
> > >  
> > >  	ret = IIO_VAL_INT;
> > >  out:
> > > -	clk_disable(adc->clk);
> > >  	mutex_unlock(&adc->aux_lock);
> > > +	clk_disable(adc->clk);
> > >  
> > >  	return ret;
> > >  }

Heiko Stübner July 14, 2020, 6:33 p.m. UTC | #13

Hi Artur,

Am Donnerstag, 9. Juli 2020, 17:21:54 CEST schrieb Artur Rojek:
> Hi all,
> 
> v8 of this patchset introduces some structural changes, which I deemed
> worthy highlighting here:
> 
>  - adc-joystick related changes have been dropped from this patchset and
>    will be upstreamed separately. Their only connection to this patchset
>    was that they used INGENIC_ADC_TOUCH_* defines in the DTS example,
>    causing trouble to Rob's scripts.

as I'm mainly eyeing your adc-joystick patch ... did you post that already
somewhere - separately as you wrote?

Thanks
Heiko

Artur Rojek July 19, 2020, 10:16 p.m. UTC | #14

On 2020-07-14 20:33, Heiko Stuebner wrote:
> Hi Artur,
> 
> Am Donnerstag, 9. Juli 2020, 17:21:54 CEST schrieb Artur Rojek:
>> Hi all,
>> 
>> v8 of this patchset introduces some structural changes, which I deemed
>> worthy highlighting here:
>> 
>>  - adc-joystick related changes have been dropped from this patchset 
>> and
>>    will be upstreamed separately. Their only connection to this 
>> patchset
>>    was that they used INGENIC_ADC_TOUCH_* defines in the DTS example,
>>    causing trouble to Rob's scripts.
> 
> as I'm mainly eyeing your adc-joystick patch ... did you post that 
> already
> somewhere - separately as you wrote?
> 
> Thanks
> Heiko

Hi Heiko,

sorry for a late reply. As you have surely noticed in your mailbox, I 
have sent the adc-joystick changes in the following series:
https://lore.kernel.org/linux-input/20200719221103.91644-1-contact@artur-rojek.eu/

Regards,
Artur

Jonathan Cameron July 20, 2020, 11:49 a.m. UTC | #15

On Sun, 12 Jul 2020 22:16:04 +0200
Paul Cercueil <paul@crapouillou.net> wrote:

> Hi Jonathan,
> 
> Le dim. 12 juil. 2020 à 14:19, Jonathan Cameron <jic23@kernel.org> a 
> écrit :
> > On Thu,  9 Jul 2020 17:22:00 +0200
> > Artur Rojek <contact@artur-rojek.eu> wrote:
> >   
> >>  The SADC component in JZ47xx SoCs provides support for touchscreen
> >>  operations (pen position and pen down pressure) in single-ended and
> >>  differential modes.
> >> 
> >>  The touchscreen component of SADC takes a significant time to 
> >> stabilize
> >>  after first receiving the clock and a delay of 50ms has been 
> >> empirically
> >>  proven to be a safe value before data sampling can begin.
> >> 
> >>  Of the known hardware to use this controller, GCW Zero and Anbernic 
> >> RG-350
> >>  utilize the touchscreen mode by having their joystick(s) attached 
> >> to the
> >>  X/Y positive/negative input pins.
> >> 
> >>  JZ4770 and later SoCs introduce a low-level command feature. With 
> >> it, up
> >>  to 32 commands can be programmed, each one corresponding to a 
> >> sampling
> >>  job. It allows to change the low-voltage reference, the high-voltage
> >>  reference, have them connected to VCC, GND, or one of the X-/X+ or 
> >> Y-/Y+
> >>  pins.
> >> 
> >>  This patch introduces support for 6 stream-capable channels:
> >>  - channel #0 samples X+/GND
> >>  - channel #1 samples Y+/GND
> >>  - channel #2 samples X-/GND
> >>  - channel #3 samples Y-/GND
> >>  - channel #4 samples X+/X-
> >>  - channel #5 samples Y+/Y-  
> > 
> > The one thing I noticed on this read was that we are slightly 
> > stretching
> > the normal IIO channel definitions.  The claim is that each of these 
> > channels
> > is a POSITIONREALTIVE channel, whereas that isn't really true.  They 
> > are
> > related to the position, but as I understand it not directly 
> > measuring it
> > (particularly X+ - X-) which is pretty much a reference voltage (I 
> > think!)
> > 
> > We might be better off just describing these as voltage channels, with
> > 4 and 5 described as differential voltage channels.  The problem there
> > being that it doesn't describe the fact that the measurements are with
> > particular voltages also being applied to the touch screen.
> > 
> > Perhaps we are best off just leaving it as you have it and being a bit
> > 'odd'.  What do you think?  Having written this down I think perhaps 
> > leaving
> > it alone is the best plan :(  
> 
> That's up to you really. These ADC channels will measure voltage, but 
> they are supposed to be used with a touchscreen, that's why we went 
> with POSITIONRELATIVE. However, with the kind of devices we're working 
> with, they are never used as such, so using VOLTAGE would work too.
I've picked up v9 as I don't think this matters hugely one way or the other.
If it becomes an issue in the long run I'm not that bothered if we end up
with one driver with a legacy and a new interface.

Thanks,

Jonathan

> 
> > Otherwise this all looks fine to me.
> > 
> > Thanks,
> > 
> > Jonathan
> >   
> >> 
> >>  Being able to sample X-/GND and Y-/GND is useful on some devices, 
> >> where
> >>  one joystick is connected to the X+/Y+ pins, and a second joystick 
> >> is
> >>  connected to the X-/Y- pins.
> >> 
> >>  All the boards which probe this driver have the interrupt provided 
> >> from
> >>  Device Tree, with no need to handle a case where the IRQ was not 
> >> provided.
> >> 
> >>  Co-developed-by: Paul Cercueil <paul@crapouillou.net>
> >>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> >>  Signed-off-by: Artur Rojek <contact@artur-rojek.eu>
> >>  ---
> >> 
> >>   Changes:
> >> 
> >>   v2: - improve description of the touchscreen mode,
> >>       - get rid of the unneeded kfifo,
> >>       - drop IIO_BUFFER_CB from Kconfig,
> >>       - remove extended names from the touchscreen channels
> >> 
> >>   v3: remove unneeded `linux/iio/kfifo_buf.h` include
> >> 
> >>   v4: clarify irq provider source in the patch description
> >> 
> >>   v5: no change
> >> 
> >>   v6: - correct the spelling of Device Tree and IRQ in commit message
> >>       - don't omit trailing commas from initializer lists
> >>       - error check `clk_enable`
> >>       - remove redundant `dev_err` from `platform_get_irq` error 
> >> check
> >> 
> >>   v7: no change
> >> 
> >>   v8: add support for ADCMD low-level command feature
> >> 
> >>   drivers/iio/adc/Kconfig       |   1 +
> >>   drivers/iio/adc/ingenic-adc.c | 250 
> >> +++++++++++++++++++++++++++++++++-
> >>   2 files changed, 249 insertions(+), 2 deletions(-)
> >> 
> >>  diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
> >>  index ff3569635ce0..5b57437cef75 100644
> >>  --- a/drivers/iio/adc/Kconfig
> >>  +++ b/drivers/iio/adc/Kconfig
> >>  @@ -500,6 +500,7 @@ config INA2XX_ADC
> >>   config INGENIC_ADC
> >>   	tristate "Ingenic JZ47xx SoCs ADC driver"
> >>   	depends on MIPS || COMPILE_TEST
> >>  +	select IIO_BUFFER
> >>   	help
> >>   	  Say yes here to build support for the Ingenic JZ47xx SoCs ADC 
> >> unit.
> >> 
> >>  diff --git a/drivers/iio/adc/ingenic-adc.c 
> >> b/drivers/iio/adc/ingenic-adc.c
> >>  index 0233a9055c86..976aea46fede 100644
> >>  --- a/drivers/iio/adc/ingenic-adc.c
> >>  +++ b/drivers/iio/adc/ingenic-adc.c
> >>  @@ -8,7 +8,9 @@
> >> 
> >>   #include <dt-bindings/iio/adc/ingenic,adc.h>
> >>   #include <linux/clk.h>
> >>  +#include <linux/iio/buffer.h>
> >>   #include <linux/iio/iio.h>
> >>  +#include <linux/interrupt.h>
> >>   #include <linux/io.h>
> >>   #include <linux/iopoll.h>
> >>   #include <linux/kernel.h>
> >>  @@ -20,19 +22,46 @@
> >>   #define JZ_ADC_REG_CFG			0x04
> >>   #define JZ_ADC_REG_CTRL			0x08
> >>   #define JZ_ADC_REG_STATUS		0x0c
> >>  +#define JZ_ADC_REG_ADSAME		0x10
> >>  +#define JZ_ADC_REG_ADWAIT		0x14
> >>   #define JZ_ADC_REG_ADTCH		0x18
> >>   #define JZ_ADC_REG_ADBDAT		0x1c
> >>   #define JZ_ADC_REG_ADSDAT		0x20
> >>  +#define JZ_ADC_REG_ADCMD		0x24
> >>   #define JZ_ADC_REG_ADCLK		0x28
> >> 
> >>   #define JZ_ADC_REG_ENABLE_PD		BIT(7)
> >>   #define JZ_ADC_REG_CFG_AUX_MD		(BIT(0) | BIT(1))
> >>   #define JZ_ADC_REG_CFG_BAT_MD		BIT(4)
> >>  +#define JZ_ADC_REG_CFG_SAMPLE_NUM(n)	((n) << 10)
> >>  +#define JZ_ADC_REG_CFG_PULL_UP(n)	((n) << 16)
> >>  +#define JZ_ADC_REG_CFG_CMD_SEL		BIT(22)
> >>  +#define JZ_ADC_REG_CFG_TOUCH_OPS_MASK	(BIT(31) | GENMASK(23, 10))
> >>   #define JZ_ADC_REG_ADCLK_CLKDIV_LSB	0
> >>   #define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB	16
> >>   #define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB	8
> >>   #define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB	16
> >> 
> >>  +#define JZ_ADC_REG_ADCMD_YNADC		BIT(7)
> >>  +#define JZ_ADC_REG_ADCMD_YPADC		BIT(8)
> >>  +#define JZ_ADC_REG_ADCMD_XNADC		BIT(9)
> >>  +#define JZ_ADC_REG_ADCMD_XPADC		BIT(10)
> >>  +#define JZ_ADC_REG_ADCMD_VREFPYP	BIT(11)
> >>  +#define JZ_ADC_REG_ADCMD_VREFPXP	BIT(12)
> >>  +#define JZ_ADC_REG_ADCMD_VREFPXN	BIT(13)
> >>  +#define JZ_ADC_REG_ADCMD_VREFPAUX	BIT(14)
> >>  +#define JZ_ADC_REG_ADCMD_VREFPVDD33	BIT(15)
> >>  +#define JZ_ADC_REG_ADCMD_VREFNYN	BIT(16)
> >>  +#define JZ_ADC_REG_ADCMD_VREFNXP	BIT(17)
> >>  +#define JZ_ADC_REG_ADCMD_VREFNXN	BIT(18)
> >>  +#define JZ_ADC_REG_ADCMD_VREFAUX	BIT(19)
> >>  +#define JZ_ADC_REG_ADCMD_YNGRU		BIT(20)
> >>  +#define JZ_ADC_REG_ADCMD_XNGRU		BIT(21)
> >>  +#define JZ_ADC_REG_ADCMD_XPGRU		BIT(22)
> >>  +#define JZ_ADC_REG_ADCMD_YPSUP		BIT(23)
> >>  +#define JZ_ADC_REG_ADCMD_XNSUP		BIT(24)
> >>  +#define JZ_ADC_REG_ADCMD_XPSUP		BIT(25)
> >>  +
> >>   #define JZ_ADC_AUX_VREF				3300
> >>   #define JZ_ADC_AUX_VREF_BITS			12
> >>   #define JZ_ADC_BATTERY_LOW_VREF			2500
> >>  @@ -44,6 +73,14 @@
> >>   #define JZ4770_ADC_BATTERY_VREF			6600
> >>   #define JZ4770_ADC_BATTERY_VREF_BITS		12
> >> 
> >>  +#define JZ_ADC_IRQ_AUX			BIT(0)
> >>  +#define JZ_ADC_IRQ_BATTERY		BIT(1)
> >>  +#define JZ_ADC_IRQ_TOUCH		BIT(2)
> >>  +#define JZ_ADC_IRQ_PEN_DOWN		BIT(3)
> >>  +#define JZ_ADC_IRQ_PEN_UP		BIT(4)
> >>  +#define JZ_ADC_IRQ_PEN_DOWN_SLEEP	BIT(5)
> >>  +#define JZ_ADC_IRQ_SLEEP		BIT(7)
> >>  +
> >>   struct ingenic_adc;
> >> 
> >>   struct ingenic_adc_soc_data {
> >>  @@ -69,6 +106,61 @@ struct ingenic_adc {
> >>   	bool low_vref_mode;
> >>   };
> >> 
> >>  +static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, 
> >> unsigned long mask)
> >>  +{
> >>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
> >>  +
> >>  +	mutex_lock(&adc->lock);
> >>  +
> >>  +	/* Init ADCMD */
> >>  +	readl(adc->base + JZ_ADC_REG_ADCMD);
> >>  +
> >>  +	if (mask & 0x3) {
> >>  +		/* Second channel (INGENIC_ADC_TOUCH_YP): sample YP vs. GND */
> >>  +		writel(JZ_ADC_REG_ADCMD_XNGRU
> >>  +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_YPADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +
> >>  +		/* First channel (INGENIC_ADC_TOUCH_XP): sample XP vs. GND */
> >>  +		writel(JZ_ADC_REG_ADCMD_YNGRU
> >>  +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_XPADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +	}
> >>  +
> >>  +	if (mask & 0xc) {
> >>  +		/* Fourth channel (INGENIC_ADC_TOUCH_YN): sample YN vs. GND */
> >>  +		writel(JZ_ADC_REG_ADCMD_XNGRU
> >>  +		       | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_YNADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +
> >>  +		/* Third channel (INGENIC_ADC_TOUCH_XN): sample XN vs. GND */
> >>  +		writel(JZ_ADC_REG_ADCMD_YNGRU
> >>  +		       | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_XNADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +	}
> >>  +
> >>  +	if (mask & 0x30) {
> >>  +		/* Sixth channel (INGENIC_ADC_TOUCH_YD): sample YP vs. YN */
> >>  +		writel(JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_YPADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +
> >>  +		/* Fifth channel (INGENIC_ADC_TOUCH_XD): sample XP vs. XN */
> >>  +		writel(JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
> >>  +		       | JZ_ADC_REG_ADCMD_XPADC,
> >>  +		       adc->base + JZ_ADC_REG_ADCMD);
> >>  +	}
> >>  +
> >>  +	/* We're done */
> >>  +	writel(0, adc->base + JZ_ADC_REG_ADCMD);
> >>  +
> >>  +	mutex_unlock(&adc->lock);
> >>  +}
> >>  +
> >>   static void ingenic_adc_set_config(struct ingenic_adc *adc,
> >>   				   uint32_t mask,
> >>   				   uint32_t val)
> >>  @@ -288,6 +380,72 @@ static const struct iio_chan_spec 
> >> jz4740_channels[] = {
> >>   };
> >> 
> >>   static const struct iio_chan_spec jz4770_channels[] = {
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_XP,  
> > 
> > Ah. sorry. I should have noticed this much earlier.
> > 
> > These aren't position channels as such.  They are channels
> > that are then processed into position in combination.
> > 
> > Problem is I'm not sure how we 'should' describe then.
> > 
> > Perhaps this is the best we can do.  
> 
> We could have the two differencial channels as IIO_POSITIONRELATIVE, 
> and the four single-ended ones as IIO_VOLTAGE.
> 
> Cheers,
> -Paul
> 
> >>  +		.scan_index = 0,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_YP,
> >>  +		.scan_index = 1,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_XN,
> >>  +		.scan_index = 2,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_YN,
> >>  +		.scan_index = 3,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_XD,
> >>  +		.scan_index = 4,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>  +	{
> >>  +		.type = IIO_POSITIONRELATIVE,
> >>  +		.indexed = 1,
> >>  +		.channel = INGENIC_ADC_TOUCH_YD,
> >>  +		.scan_index = 5,
> >>  +		.scan_type = {
> >>  +			.sign = 'u',
> >>  +			.realbits = 12,
> >>  +			.storagebits = 16,
> >>  +		},
> >>  +	},
> >>   	{
> >>   		.extend_name = "aux",
> >>   		.type = IIO_VOLTAGE,
> >>  @@ -490,13 +648,89 @@ static const struct iio_info ingenic_adc_info 
> >> = {
> >>   	.of_xlate = ingenic_adc_of_xlate,
> >>   };
> >> 
> >>  +static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev)
> >>  +{
> >>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
> >>  +	int ret;
> >>  +
> >>  +	ret = clk_enable(adc->clk);
> >>  +	if (ret) {
> >>  +		dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
> >>  +			ret);
> >>  +		return ret;
> >>  +	}
> >>  +
> >>  +	/* It takes significant time for the touchscreen hw to stabilize. 
> >> */
> >>  +	msleep(50);
> >>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK,
> >>  +			       JZ_ADC_REG_CFG_SAMPLE_NUM(4) |
> >>  +			       JZ_ADC_REG_CFG_PULL_UP(4));
> >>  +
> >>  +	writew(80, adc->base + JZ_ADC_REG_ADWAIT);
> >>  +	writew(2, adc->base + JZ_ADC_REG_ADSAME);
> >>  +	writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL);
> >>  +	writel(0, adc->base + JZ_ADC_REG_ADTCH);
> >>  +
> >>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL,
> >>  +			       JZ_ADC_REG_CFG_CMD_SEL);
> >>  +	ingenic_adc_set_adcmd(iio_dev, iio_dev->active_scan_mask[0]);
> >>  +
> >>  +	ingenic_adc_enable(adc, 2, true);
> >>  +
> >>  +	return 0;
> >>  +}
> >>  +
> >>  +static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev)
> >>  +{
> >>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
> >>  +
> >>  +	ingenic_adc_enable(adc, 2, false);
> >>  +
> >>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL, 0);
> >>  +
> >>  +	writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
> >>  +	writeb(0xff, adc->base + JZ_ADC_REG_STATUS);
> >>  +	ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0);
> >>  +	writew(0, adc->base + JZ_ADC_REG_ADSAME);
> >>  +	writew(0, adc->base + JZ_ADC_REG_ADWAIT);
> >>  +	clk_disable(adc->clk);
> >>  +
> >>  +	return 0;
> >>  +}
> >>  +
> >>  +static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops 
> >> = {
> >>  +	.postenable = &ingenic_adc_buffer_enable,
> >>  +	.predisable = &ingenic_adc_buffer_disable
> >>  +};
> >>  +
> >>  +static irqreturn_t ingenic_adc_irq(int irq, void *data)
> >>  +{
> >>  +	struct iio_dev *iio_dev = data;
> >>  +	struct ingenic_adc *adc = iio_priv(iio_dev);
> >>  +	unsigned long mask = iio_dev->active_scan_mask[0];
> >>  +	unsigned int i;
> >>  +	u32 tdat[3];
> >>  +
> >>  +	for (i = 0; i < ARRAY_SIZE(tdat); mask >>= 2, i++) {
> >>  +		if (mask & 0x3)
> >>  +			tdat[i] = readl(adc->base + JZ_ADC_REG_ADTCH);
> >>  +		else
> >>  +			tdat[i] = 0;
> >>  +	}
> >>  +
> >>  +	iio_push_to_buffers(iio_dev, tdat);
> >>  +	writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS);
> >>  +
> >>  +	return IRQ_HANDLED;
> >>  +}
> >>  +
> >>   static int ingenic_adc_probe(struct platform_device *pdev)
> >>   {
> >>   	struct device *dev = &pdev->dev;
> >>   	struct iio_dev *iio_dev;
> >>   	struct ingenic_adc *adc;
> >>   	const struct ingenic_adc_soc_data *soc_data;
> >>  -	int ret;
> >>  +	int irq, ret;
> >> 
> >>   	soc_data = device_get_match_data(dev);
> >>   	if (!soc_data)
> >>  @@ -511,6 +745,17 @@ static int ingenic_adc_probe(struct 
> >> platform_device *pdev)
> >>   	mutex_init(&adc->aux_lock);
> >>   	adc->soc_data = soc_data;
> >> 
> >>  +	irq = platform_get_irq(pdev, 0);
> >>  +	if (irq < 0)
> >>  +		return irq;
> >>  +
> >>  +	ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0,
> >>  +			       dev_name(dev), iio_dev);
> >>  +	if (ret < 0) {
> >>  +		dev_err(dev, "Failed to request irq: %d\n", ret);
> >>  +		return ret;
> >>  +	}
> >>  +
> >>   	adc->base = devm_platform_ioremap_resource(pdev, 0);
> >>   	if (IS_ERR(adc->base))
> >>   		return PTR_ERR(adc->base);
> >>  @@ -550,7 +795,8 @@ static int ingenic_adc_probe(struct 
> >> platform_device *pdev)
> >> 
> >>   	iio_dev->dev.parent = dev;
> >>   	iio_dev->name = "jz-adc";
> >>  -	iio_dev->modes = INDIO_DIRECT_MODE;
> >>  +	iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> >>  +	iio_dev->setup_ops = &ingenic_buffer_setup_ops;
> >>   	iio_dev->channels = soc_data->channels;
> >>   	iio_dev->num_channels = soc_data->num_channels;
> >>   	iio_dev->info = &ingenic_adc_info;  
> >   
> 
>

[v8,0/6] iio/adc: ingenic: Cleanups & add touchscreen mode.

Message

Comments