leds: add LED driver for CR0014114 board

Message ID 20180312153323.9200-1-oleg@kaa.org.ua
State Superseded
Headers show
Series
  • leds: add LED driver for CR0014114 board
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Commit Message

Oleh Kravchenko March 12, 2018, 3:33 p.m.
This patch adds a LED class driver for the RGB LEDs found on
the Crane Merchandising System CR0014114 LEDs board.

Signed-off-by: Oleh Kravchenko <oleg@kaa.org.ua>
---
 .../devicetree/bindings/leds/leds-cr0014114.txt    |  46 ++++
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 drivers/leds/Kconfig                               |  13 +
 drivers/leds/Makefile                              |   1 +
 drivers/leds/leds-cr0014114.c                      | 282 +++++++++++++++++++++
 5 files changed, 343 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
 create mode 100644 drivers/leds/leds-cr0014114.c

Comments

Peter Meerwald-Stadler March 12, 2018, 3:45 p.m. | #1
trivial comments below

> This patch adds a LED class driver for the RGB LEDs found on
> the Crane Merchandising System CR0014114 LEDs board.
> 
> Signed-off-by: Oleh Kravchenko <oleg@kaa.org.ua>
> ---
>  .../devicetree/bindings/leds/leds-cr0014114.txt    |  46 ++++
>  .../devicetree/bindings/vendor-prefixes.txt        |   1 +
>  drivers/leds/Kconfig                               |  13 +
>  drivers/leds/Makefile                              |   1 +
>  drivers/leds/leds-cr0014114.c                      | 282 +++++++++++++++++++++
>  5 files changed, 343 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>  create mode 100644 drivers/leds/leds-cr0014114.c
> 
> diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
> new file mode 100644
> index 000000000000..56721598ee81
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
> @@ -0,0 +1,46 @@
> +Crane Merchandising System - cr0014114 LED driver
> +-------------------------------------------------
> +
> +This LED Board widely used in vending machines produced

_is_ widely used

> +by Crane Merchandising Systems.
> +
> +Required properties:
> +- compatible: "cms,cr0014114"
> +- reg: chip select address for the device
> +- spi-cpha: shifted clock phase mode is required
> +
> +LED sub-node properties:
> +- label : (optional)
> +	see Documentation/devicetree/bindings/leds/common.txt
> +- linux,default-trigger : (optional)
> +	see Documentation/devicetree/bindings/leds/common.txt
> +
> +Example
> +-------
> +
> +cr0014114@0 {
> +	compatible = "crane,cr0014114";
> +	reg = <0>;
> +	spi-max-frequency = <50000>;
> +	spi-cpha;
> +
> +	led0 {
> +		label = "cr0:red:";
> +	};
> +	led1 {
> +		label = "cr0:green:";
> +	};
> +	led2 {
> +		label = "cr0:blue:";
> +	};
> +	led3 {
> +		label = "cr1:red:";
> +	};
> +	led4 {
> +		label = "cr1:green:";
> +	};
> +	led5 {
> +		label = "cr1:blue:";
> +	};
> +	...
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index ae850d6c0ad3..f17949c365f5 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -75,6 +75,7 @@ cnxt	Conexant Systems, Inc.
>  compulab	CompuLab Ltd.
>  cortina	Cortina Systems, Inc.
>  cosmic	Cosmic Circuits
> +crane	Crane Connectivity Solutions
>  creative	Creative Technology Ltd
>  crystalfontz	Crystalfontz America, Inc.
>  cubietech	Cubietech, Ltd.
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 2c896c0e69e1..bb6a70ac5004 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -104,6 +104,19 @@ config LEDS_CPCAP
>  	  This option enables support for LEDs offered by Motorola's
>  	  CPCAP PMIC.
>  
> +config LEDS_CR0014114
> +	tristate "LED Support for Crane CR0014114"
> +	depends on LEDS_CLASS
> +	depends on SPI
> +	depends on OF
> +	help
> +	  This option enables support for CR0014114 LED Board which
> +	  widely used in vending machines produced by

is widely

> +	  Crane Merchandising Systems.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called leds-cr0014114.
> +
>  config LEDS_LM3530
>  	tristate "LCD Backlight driver for LM3530"
>  	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 91eca81cae82..0176e7335994 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -78,6 +78,7 @@ obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o
>  obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o
>  
>  # LED SPI Drivers
> +obj-$(CONFIG_LEDS_CR0014114)		+= leds-cr0014114.o
>  obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
>  
>  # LED Userspace Drivers
> diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
> new file mode 100644
> index 000000000000..e3aecdbea73c
> --- /dev/null
> +++ b/drivers/leds/leds-cr0014114.c
> @@ -0,0 +1,282 @@
> +#include <linux/delay.h>
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/property.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spinlock.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>
> +
> +/* CR0014114 SPI commands */
> +#define CR_SET_BRIGHTNESS	0x80
> +#define CR_INIT_REENUMERATE	0x81
> +#define CR_NEXT_REENUMERATE	0x82
> +
> +/* CR0014114 default settings */
> +#define CR_MAX_BRIGHTNESS	GENMASK(6, 0)
> +#define CR_FW_DELAY_MSEC	10
> +#define CR_RECOUNT_DELAY	(HZ * 3600)
> +
> +struct cr0014114_led {
> +	const char		*name;
> +	struct cr0014114	*priv;
> +	struct led_classdev	ldev;
> +	u8			brightness;
> +};
> +
> +struct cr0014114 {
> +	bool			do_recount;
> +	size_t			count;
> +	struct device		*dev;
> +	struct mutex		lock;
> +	struct spi_device	*spi;
> +	struct timer_list	timer;
> +	struct work_struct	work;
> +	unsigned long		delay;
> +	struct cr0014114_led	leds[];
> +};
> +
> +static void cr0014114_calc_crc(u8 *buf, const size_t len)
> +{
> +	size_t	i;
> +	u8	crc;
> +
> +	for (i = 1, crc = 1; i < len - 1; i++)
> +		crc += buf[i];
> +	crc |= BIT(7);
> +
> +	/* special case when CRC matches to SPI commands */

matches the

> +	if (crc == CR_SET_BRIGHTNESS ||
> +	    crc == CR_INIT_REENUMERATE ||
> +	    crc == CR_NEXT_REENUMERATE)
> +		crc = 0xfe;
> +
> +	buf[len - 1] = crc;
> +}
> +
> +static int cr0014114_recount(struct cr0014114 *priv)
> +{
> +	int	ret;
> +	size_t	i;
> +	u8	cmd;
> +
> +	dev_dbg(priv->dev, "recount of LEDs is started\n");
> +
> +	do {
> +		cmd = CR_INIT_REENUMERATE;
> +		ret = spi_write(priv->spi, &cmd, sizeof(cmd));
> +		if (ret)
> +			break;
> +
> +		cmd = CR_NEXT_REENUMERATE;
> +		for (i = 0; i < priv->count; i++) {
> +			msleep(CR_FW_DELAY_MSEC);
> +
> +			ret = spi_write(priv->spi, &cmd, sizeof(cmd));
> +			if (ret)
> +				break;
> +		}
> +	} while (0);
> +
> +	dev_dbg(priv->dev, "recount of LEDs is complete, error: %d\n", ret);
> +
> +	return ret;
> +}
> +
> +static int cr0014114_sync(struct cr0014114 *priv)
> +{
> +	int		ret;
> +	size_t		i;
> +	u8		data[priv->count + 2];
> +	unsigned long	udelay, now = jiffies;
> +
> +	/* to avoid SPI mistiming with firmware we should wait some time */
> +	if (time_after(priv->delay, now)) {
> +		udelay = jiffies_to_usecs(priv->delay - now);
> +		usleep_range(udelay, udelay + 1);
> +	}
> +
> +	do {
> +		if (unlikely(priv->do_recount)) {
> +			ret = cr0014114_recount(priv);
> +			if (ret)
> +				break;
> +
> +			priv->do_recount = false;
> +		}
> +
> +		data[0] = CR_SET_BRIGHTNESS;
> +		for (i = 0; i < priv->count; i++)
> +			data[i + 1] = priv->leds[i].brightness;
> +		cr0014114_calc_crc(data, sizeof(data));
> +
> +		ret = spi_write(priv->spi, data, sizeof(data));
> +		if (ret)
> +			break;
> +	} while (0);
> +
> +	priv->delay = jiffies + msecs_to_jiffies(CR_FW_DELAY_MSEC);
> +
> +	return ret;
> +}
> +
> +static void cr0014114_recount_work(struct work_struct *work)
> +{
> +	int			ret;
> +	struct cr0014114	*priv = container_of(work, struct cr0014114,
> +						     work);
> +
> +	mutex_lock(&priv->lock);
> +	priv->do_recount = true;
> +	ret = cr0014114_sync(priv);
> +	mutex_unlock(&priv->lock);
> +
> +	if (ret)
> +		dev_warn(priv->dev, "recount LEDs failed %d\n", ret);
> +}
> +
> +int cr0014114_set_sync(struct led_classdev *ldev,

static?

> +		       enum led_brightness brightness)
> +{
> +	int			ret;
> +	struct cr0014114_led    *led = container_of(ldev,
> +						    struct cr0014114_led,
> +						    ldev);
> +
> +	mutex_lock(&led->priv->lock);
> +	led->brightness = (u8)brightness;
> +	ret = cr0014114_sync(led->priv);
> +	mutex_unlock(&led->priv->lock);
> +
> +	return ret;
> +}
> +
> +void cr0014114_recount_timer(struct timer_list *t)

static?

> +{
> +	struct cr0014114 *priv = from_timer(priv, t, timer);
> +
> +	schedule_work(&priv->work);
> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
> +}
> +
> +static int cr0014114_probe_dt(struct cr0014114 *priv)
> +{
> +	size_t			i = 0;
> +	struct cr0014114_led	*led;
> +	struct fwnode_handle	*child;
> +	struct device_node	*np;
> +	int			ret;
> +
> +	device_for_each_child_node(priv->dev, child) {
> +		np = to_of_node(child);
> +		led = &priv->leds[i];
> +
> +		ret = fwnode_property_read_string(child, "label",
> +						  &led->name);
> +		if (ret && IS_ENABLED(CONFIG_OF) && np)
> +			led->name = np->name;
> +
> +		if (!led->name) {
> +			fwnode_handle_put(child);
> +			return -EINVAL;
> +		}
> +
> +		fwnode_property_read_string(child, "linux,default-trigger",
> +					    &led->ldev.default_trigger);
> +
> +		led->priv			  = priv;
> +		led->ldev.name			  = led->name;
> +		led->ldev.brightness		  = LED_OFF;
> +		led->ldev.max_brightness	  = CR_MAX_BRIGHTNESS;
> +		led->ldev.brightness_set_blocking = cr0014114_set_sync;
> +
> +		ret = devm_of_led_classdev_register(priv->dev, np,
> +						    &led->ldev);
> +		if (ret) {
> +			fwnode_handle_put(child);
> +			return ret;
> +		}
> +
> +		led->ldev.dev->of_node = np;
> +
> +		i++;
> +	}
> +
> +	return 0;
> +}
> +
> +static int cr0014114_probe(struct spi_device *spi)
> +{
> +	struct cr0014114	*priv;
> +	size_t			count;
> +	int			ret;
> +
> +	count = device_get_child_node_count(&spi->dev);
> +	if (!count) {
> +		dev_err(&spi->dev, "LEDs are not defined in device tree");
> +		return -ENODEV;
> +	}
> +
> +	priv = devm_kzalloc(&spi->dev,
> +			    sizeof(*priv) + sizeof(*priv->leds) * count,
> +			    GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	mutex_init(&priv->lock);
> +	INIT_WORK(&priv->work, cr0014114_recount_work);
> +	priv->do_recount	= true;
> +	priv->count		= count;
> +	priv->dev		= &spi->dev;
> +	priv->spi		= spi;
> +
> +	ret = cr0014114_probe_dt(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = cr0014114_sync(priv);
> +	if (ret)
> +		return ret;
> +
> +	/* setup recount timer to workaround buggy firmware */
> +	timer_setup(&priv->timer, cr0014114_recount_timer, 0);
> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
> +
> +	spi_set_drvdata(spi, priv);
> +
> +	return 0;
> +}
> +
> +static int cr0014114_remove(struct spi_device *spi)
> +{
> +	struct cr0014114 *priv = spi_get_drvdata(spi);
> +
> +	cancel_work_sync(&priv->work);
> +	del_timer_sync(&priv->timer);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id cr0014114_dt_ids[] = {
> +	{ .compatible = "crane,cr0014114", },
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
> +
> +static struct spi_driver cr0014114_driver = {
> +	.probe		= cr0014114_probe,
> +	.remove		= cr0014114_remove,
> +	.driver = {
> +		.name		= KBUILD_MODNAME,
> +		.of_match_table	= cr0014114_dt_ids,
> +	},
> +};
> +
> +module_spi_driver(cr0014114_driver);
> +
> +MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
> +MODULE_DESCRIPTION("cr0014114 LED driver");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("spi:cr0014114");
>
Oleh Kravchenko March 12, 2018, 3:54 p.m. | #2
Thanks for comments.


On 12.03.18 17:45, Peter Meerwald-Stadler wrote:
> trivial comments below
>
>> This patch adds a LED class driver for the RGB LEDs found on
>> the Crane Merchandising System CR0014114 LEDs board.
>>
>> Signed-off-by: Oleh Kravchenko <oleg@kaa.org.ua>
>> ---
>>  .../devicetree/bindings/leds/leds-cr0014114.txt    |  46 ++++
>>  .../devicetree/bindings/vendor-prefixes.txt        |   1 +
>>  drivers/leds/Kconfig                               |  13 +
>>  drivers/leds/Makefile                              |   1 +
>>  drivers/leds/leds-cr0014114.c                      | 282 +++++++++++++++++++++
>>  5 files changed, 343 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>>  create mode 100644 drivers/leds/leds-cr0014114.c
>>
>> diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>> new file mode 100644
>> index 000000000000..56721598ee81
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>> @@ -0,0 +1,46 @@
>> +Crane Merchandising System - cr0014114 LED driver
>> +-------------------------------------------------
>> +
>> +This LED Board widely used in vending machines produced
> _is_ widely used
>
>> +by Crane Merchandising Systems.
>> +
>> +Required properties:
>> +- compatible: "cms,cr0014114"
>> +- reg: chip select address for the device
>> +- spi-cpha: shifted clock phase mode is required
>> +
>> +LED sub-node properties:
>> +- label : (optional)
>> +	see Documentation/devicetree/bindings/leds/common.txt
>> +- linux,default-trigger : (optional)
>> +	see Documentation/devicetree/bindings/leds/common.txt
>> +
>> +Example
>> +-------
>> +
>> +cr0014114@0 {
>> +	compatible = "crane,cr0014114";
>> +	reg = <0>;
>> +	spi-max-frequency = <50000>;
>> +	spi-cpha;
>> +
>> +	led0 {
>> +		label = "cr0:red:";
>> +	};
>> +	led1 {
>> +		label = "cr0:green:";
>> +	};
>> +	led2 {
>> +		label = "cr0:blue:";
>> +	};
>> +	led3 {
>> +		label = "cr1:red:";
>> +	};
>> +	led4 {
>> +		label = "cr1:green:";
>> +	};
>> +	led5 {
>> +		label = "cr1:blue:";
>> +	};
>> +	...
>> +};
>> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> index ae850d6c0ad3..f17949c365f5 100644
>> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
>> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
>> @@ -75,6 +75,7 @@ cnxt	Conexant Systems, Inc.
>>  compulab	CompuLab Ltd.
>>  cortina	Cortina Systems, Inc.
>>  cosmic	Cosmic Circuits
>> +crane	Crane Connectivity Solutions
>>  creative	Creative Technology Ltd
>>  crystalfontz	Crystalfontz America, Inc.
>>  cubietech	Cubietech, Ltd.
>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
>> index 2c896c0e69e1..bb6a70ac5004 100644
>> --- a/drivers/leds/Kconfig
>> +++ b/drivers/leds/Kconfig
>> @@ -104,6 +104,19 @@ config LEDS_CPCAP
>>  	  This option enables support for LEDs offered by Motorola's
>>  	  CPCAP PMIC.
>>  
>> +config LEDS_CR0014114
>> +	tristate "LED Support for Crane CR0014114"
>> +	depends on LEDS_CLASS
>> +	depends on SPI
>> +	depends on OF
>> +	help
>> +	  This option enables support for CR0014114 LED Board which
>> +	  widely used in vending machines produced by
> is widely
>
>> +	  Crane Merchandising Systems.
>> +
>> +	  To compile this driver as a module, choose M here: the module
>> +	  will be called leds-cr0014114.
>> +
>>  config LEDS_LM3530
>>  	tristate "LCD Backlight driver for LM3530"
>>  	depends on LEDS_CLASS
>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
>> index 91eca81cae82..0176e7335994 100644
>> --- a/drivers/leds/Makefile
>> +++ b/drivers/leds/Makefile
>> @@ -78,6 +78,7 @@ obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o
>>  obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o
>>  
>>  # LED SPI Drivers
>> +obj-$(CONFIG_LEDS_CR0014114)		+= leds-cr0014114.o
>>  obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
>>  
>>  # LED Userspace Drivers
>> diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
>> new file mode 100644
>> index 000000000000..e3aecdbea73c
>> --- /dev/null
>> +++ b/drivers/leds/leds-cr0014114.c
>> @@ -0,0 +1,282 @@
>> +#include <linux/delay.h>
>> +#include <linux/leds.h>
>> +#include <linux/module.h>
>> +#include <linux/of_device.h>
>> +#include <linux/property.h>
>> +#include <linux/spi/spi.h>
>> +#include <linux/spinlock.h>
>> +#include <linux/timer.h>
>> +#include <linux/workqueue.h>
>> +
>> +/* CR0014114 SPI commands */
>> +#define CR_SET_BRIGHTNESS	0x80
>> +#define CR_INIT_REENUMERATE	0x81
>> +#define CR_NEXT_REENUMERATE	0x82
>> +
>> +/* CR0014114 default settings */
>> +#define CR_MAX_BRIGHTNESS	GENMASK(6, 0)
>> +#define CR_FW_DELAY_MSEC	10
>> +#define CR_RECOUNT_DELAY	(HZ * 3600)
>> +
>> +struct cr0014114_led {
>> +	const char		*name;
>> +	struct cr0014114	*priv;
>> +	struct led_classdev	ldev;
>> +	u8			brightness;
>> +};
>> +
>> +struct cr0014114 {
>> +	bool			do_recount;
>> +	size_t			count;
>> +	struct device		*dev;
>> +	struct mutex		lock;
>> +	struct spi_device	*spi;
>> +	struct timer_list	timer;
>> +	struct work_struct	work;
>> +	unsigned long		delay;
>> +	struct cr0014114_led	leds[];
>> +};
>> +
>> +static void cr0014114_calc_crc(u8 *buf, const size_t len)
>> +{
>> +	size_t	i;
>> +	u8	crc;
>> +
>> +	for (i = 1, crc = 1; i < len - 1; i++)
>> +		crc += buf[i];
>> +	crc |= BIT(7);
>> +
>> +	/* special case when CRC matches to SPI commands */
> matches the
>
>> +	if (crc == CR_SET_BRIGHTNESS ||
>> +	    crc == CR_INIT_REENUMERATE ||
>> +	    crc == CR_NEXT_REENUMERATE)
>> +		crc = 0xfe;
>> +
>> +	buf[len - 1] = crc;
>> +}
>> +
>> +static int cr0014114_recount(struct cr0014114 *priv)
>> +{
>> +	int	ret;
>> +	size_t	i;
>> +	u8	cmd;
>> +
>> +	dev_dbg(priv->dev, "recount of LEDs is started\n");
>> +
>> +	do {
>> +		cmd = CR_INIT_REENUMERATE;
>> +		ret = spi_write(priv->spi, &cmd, sizeof(cmd));
>> +		if (ret)
>> +			break;
>> +
>> +		cmd = CR_NEXT_REENUMERATE;
>> +		for (i = 0; i < priv->count; i++) {
>> +			msleep(CR_FW_DELAY_MSEC);
>> +
>> +			ret = spi_write(priv->spi, &cmd, sizeof(cmd));
>> +			if (ret)
>> +				break;
>> +		}
>> +	} while (0);
>> +
>> +	dev_dbg(priv->dev, "recount of LEDs is complete, error: %d\n", ret);
>> +
>> +	return ret;
>> +}
>> +
>> +static int cr0014114_sync(struct cr0014114 *priv)
>> +{
>> +	int		ret;
>> +	size_t		i;
>> +	u8		data[priv->count + 2];
>> +	unsigned long	udelay, now = jiffies;
>> +
>> +	/* to avoid SPI mistiming with firmware we should wait some time */
>> +	if (time_after(priv->delay, now)) {
>> +		udelay = jiffies_to_usecs(priv->delay - now);
>> +		usleep_range(udelay, udelay + 1);
>> +	}
>> +
>> +	do {
>> +		if (unlikely(priv->do_recount)) {
>> +			ret = cr0014114_recount(priv);
>> +			if (ret)
>> +				break;
>> +
>> +			priv->do_recount = false;
>> +		}
>> +
>> +		data[0] = CR_SET_BRIGHTNESS;
>> +		for (i = 0; i < priv->count; i++)
>> +			data[i + 1] = priv->leds[i].brightness;
>> +		cr0014114_calc_crc(data, sizeof(data));
>> +
>> +		ret = spi_write(priv->spi, data, sizeof(data));
>> +		if (ret)
>> +			break;
>> +	} while (0);
>> +
>> +	priv->delay = jiffies + msecs_to_jiffies(CR_FW_DELAY_MSEC);
>> +
>> +	return ret;
>> +}
>> +
>> +static void cr0014114_recount_work(struct work_struct *work)
>> +{
>> +	int			ret;
>> +	struct cr0014114	*priv = container_of(work, struct cr0014114,
>> +						     work);
>> +
>> +	mutex_lock(&priv->lock);
>> +	priv->do_recount = true;
>> +	ret = cr0014114_sync(priv);
>> +	mutex_unlock(&priv->lock);
>> +
>> +	if (ret)
>> +		dev_warn(priv->dev, "recount LEDs failed %d\n", ret);
>> +}
>> +
>> +int cr0014114_set_sync(struct led_classdev *ldev,
> static?
>
>> +		       enum led_brightness brightness)
>> +{
>> +	int			ret;
>> +	struct cr0014114_led    *led = container_of(ldev,
>> +						    struct cr0014114_led,
>> +						    ldev);
>> +
>> +	mutex_lock(&led->priv->lock);
>> +	led->brightness = (u8)brightness;
>> +	ret = cr0014114_sync(led->priv);
>> +	mutex_unlock(&led->priv->lock);
>> +
>> +	return ret;
>> +}
>> +
>> +void cr0014114_recount_timer(struct timer_list *t)
> static?
>
>> +{
>> +	struct cr0014114 *priv = from_timer(priv, t, timer);
>> +
>> +	schedule_work(&priv->work);
>> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
>> +}
>> +
>> +static int cr0014114_probe_dt(struct cr0014114 *priv)
>> +{
>> +	size_t			i = 0;
>> +	struct cr0014114_led	*led;
>> +	struct fwnode_handle	*child;
>> +	struct device_node	*np;
>> +	int			ret;
>> +
>> +	device_for_each_child_node(priv->dev, child) {
>> +		np = to_of_node(child);
>> +		led = &priv->leds[i];
>> +
>> +		ret = fwnode_property_read_string(child, "label",
>> +						  &led->name);
>> +		if (ret && IS_ENABLED(CONFIG_OF) && np)
>> +			led->name = np->name;
>> +
>> +		if (!led->name) {
>> +			fwnode_handle_put(child);
>> +			return -EINVAL;
>> +		}
>> +
>> +		fwnode_property_read_string(child, "linux,default-trigger",
>> +					    &led->ldev.default_trigger);
>> +
>> +		led->priv			  = priv;
>> +		led->ldev.name			  = led->name;
>> +		led->ldev.brightness		  = LED_OFF;
>> +		led->ldev.max_brightness	  = CR_MAX_BRIGHTNESS;
>> +		led->ldev.brightness_set_blocking = cr0014114_set_sync;
>> +
>> +		ret = devm_of_led_classdev_register(priv->dev, np,
>> +						    &led->ldev);
>> +		if (ret) {
>> +			fwnode_handle_put(child);
>> +			return ret;
>> +		}
>> +
>> +		led->ldev.dev->of_node = np;
>> +
>> +		i++;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int cr0014114_probe(struct spi_device *spi)
>> +{
>> +	struct cr0014114	*priv;
>> +	size_t			count;
>> +	int			ret;
>> +
>> +	count = device_get_child_node_count(&spi->dev);
>> +	if (!count) {
>> +		dev_err(&spi->dev, "LEDs are not defined in device tree");
>> +		return -ENODEV;
>> +	}
>> +
>> +	priv = devm_kzalloc(&spi->dev,
>> +			    sizeof(*priv) + sizeof(*priv->leds) * count,
>> +			    GFP_KERNEL);
>> +	if (!priv)
>> +		return -ENOMEM;
>> +
>> +	mutex_init(&priv->lock);
>> +	INIT_WORK(&priv->work, cr0014114_recount_work);
>> +	priv->do_recount	= true;
>> +	priv->count		= count;
>> +	priv->dev		= &spi->dev;
>> +	priv->spi		= spi;
>> +
>> +	ret = cr0014114_probe_dt(priv);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = cr0014114_sync(priv);
>> +	if (ret)
>> +		return ret;
>> +
>> +	/* setup recount timer to workaround buggy firmware */
>> +	timer_setup(&priv->timer, cr0014114_recount_timer, 0);
>> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
>> +
>> +	spi_set_drvdata(spi, priv);
>> +
>> +	return 0;
>> +}
>> +
>> +static int cr0014114_remove(struct spi_device *spi)
>> +{
>> +	struct cr0014114 *priv = spi_get_drvdata(spi);
>> +
>> +	cancel_work_sync(&priv->work);
>> +	del_timer_sync(&priv->timer);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id cr0014114_dt_ids[] = {
>> +	{ .compatible = "crane,cr0014114", },
>> +	{},
>> +};
>> +
>> +MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
>> +
>> +static struct spi_driver cr0014114_driver = {
>> +	.probe		= cr0014114_probe,
>> +	.remove		= cr0014114_remove,
>> +	.driver = {
>> +		.name		= KBUILD_MODNAME,
>> +		.of_match_table	= cr0014114_dt_ids,
>> +	},
>> +};
>> +
>> +module_spi_driver(cr0014114_driver);
>> +
>> +MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
>> +MODULE_DESCRIPTION("cr0014114 LED driver");
>> +MODULE_LICENSE("GPL");
>> +MODULE_ALIAS("spi:cr0014114");
>>
Jacek Anaszewski March 17, 2018, 8:19 a.m. | #3
Hi Oleh,

Thank you for the patch. Please see my comments below.

On 03/12/2018 04:33 PM, Oleh Kravchenko wrote:
> This patch adds a LED class driver for the RGB LEDs found on
> the Crane Merchandising System CR0014114 LEDs board.
> 
> Signed-off-by: Oleh Kravchenko <oleg@kaa.org.ua>
> ---
>  .../devicetree/bindings/leds/leds-cr0014114.txt    |  46 ++++
>  .../devicetree/bindings/vendor-prefixes.txt        |   1 +
>  drivers/leds/Kconfig                               |  13 +
>  drivers/leds/Makefile                              |   1 +
>  drivers/leds/leds-cr0014114.c                      | 282 +++++++++++++++++++++
>  5 files changed, 343 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
>  create mode 100644 drivers/leds/leds-cr0014114.c
> 
> diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
> new file mode 100644
> index 000000000000..56721598ee81
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt

Please split DT bindings related changes to the separate patch.

> @@ -0,0 +1,46 @@
> +Crane Merchandising System - cr0014114 LED driver
> +-------------------------------------------------
> +
> +This LED Board widely used in vending machines produced
> +by Crane Merchandising Systems.
> +
> +Required properties:
> +- compatible: "cms,cr0014114"

Why here cms and crane in the example below? Please make it
consistent. I assume that vendor prefix should be "crane",
so in this case this should look like below:

- compatible: Must be "crane,cr0014114".

> +- reg: chip select address for the device
> +- spi-cpha: shifted clock phase mode is required

You don't have to say that it is required - it is already
under "Required properties". Apart from that - you don't
parse this property in the driver, so it doesn't seem to
be needed.

> +
> +LED sub-node properties:
> +- label : (optional)
> +	see Documentation/devicetree/bindings/leds/common.txt
> +- linux,default-trigger : (optional)
> +	see Documentation/devicetree/bindings/leds/common.txt
> +
> +Example
> +-------
> +
> +cr0014114@0 {

led-controller@9

> +	compatible = "crane,cr0014114";

You need also below properties to avoid dtc warnings.

#address-cells = <1>;
#size-cells = <0>;


> +	reg = <0>;
> +	spi-max-frequency = <50000>;
> +	spi-cpha;

Please consider if this is really required.

> +	led0 {
> +		label = "cr0:red:";

Please separate "led" from the address with "@" character,
e.g. here it should be led@0.

Also why "cr0" and not full device name "cr0014114"?
You could also think of some exemplary LED functions to not
leave that section empty.


> +	};
> +	led1 {
> +		label = "cr0:green:";
> +	};
> +	led2 {
> +		label = "cr0:blue:";
> +	};
> +	led3 {
> +		label = "cr1:red:";
> +	};
> +	led4 {
> +		label = "cr1:green:";
> +	};
> +	led5 {
> +		label = "cr1:blue:";
> +	};
> +	...
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index ae850d6c0ad3..f17949c365f5 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -75,6 +75,7 @@ cnxt	Conexant Systems, Inc.
>  compulab	CompuLab Ltd.
>  cortina	Cortina Systems, Inc.
>  cosmic	Cosmic Circuits
> +crane	Crane Connectivity Solutions
>  creative	Creative Technology Ltd
>  crystalfontz	Crystalfontz America, Inc.
>  cubietech	Cubietech, Ltd.
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 2c896c0e69e1..bb6a70ac5004 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -104,6 +104,19 @@ config LEDS_CPCAP
>  	  This option enables support for LEDs offered by Motorola's
>  	  CPCAP PMIC.
>  
> +config LEDS_CR0014114
> +	tristate "LED Support for Crane CR0014114"
> +	depends on LEDS_CLASS
> +	depends on SPI
> +	depends on OF
> +	help
> +	  This option enables support for CR0014114 LED Board which
> +	  widely used in vending machines produced by
> +	  Crane Merchandising Systems.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called leds-cr0014114.
> +
>  config LEDS_LM3530
>  	tristate "LCD Backlight driver for LM3530"
>  	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 91eca81cae82..0176e7335994 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -78,6 +78,7 @@ obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o
>  obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o
>  
>  # LED SPI Drivers
> +obj-$(CONFIG_LEDS_CR0014114)		+= leds-cr0014114.o
>  obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
>  
>  # LED Userspace Drivers
> diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
> new file mode 100644
> index 000000000000..e3aecdbea73c
> --- /dev/null
> +++ b/drivers/leds/leds-cr0014114.c
> @@ -0,0 +1,282 @@
> +#include <linux/delay.h>
> +#include <linux/leds.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/property.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spinlock.h>
> +#include <linux/timer.h>
> +#include <linux/workqueue.h>
> +
> +/* CR0014114 SPI commands */
> +#define CR_SET_BRIGHTNESS	0x80
> +#define CR_INIT_REENUMERATE	0x81
> +#define CR_NEXT_REENUMERATE	0x82
> +
> +/* CR0014114 default settings */
> +#define CR_MAX_BRIGHTNESS	GENMASK(6, 0)
> +#define CR_FW_DELAY_MSEC	10
> +#define CR_RECOUNT_DELAY	(HZ * 3600)
> +
> +struct cr0014114_led {
> +	const char		*name;
> +	struct cr0014114	*priv;
> +	struct led_classdev	ldev;
> +	u8			brightness;
> +};
> +
> +struct cr0014114 {
> +	bool			do_recount;
> +	size_t			count;
> +	struct device		*dev;
> +	struct mutex		lock;
> +	struct spi_device	*spi;
> +	struct timer_list	timer;
> +	struct work_struct	work;
> +	unsigned long		delay;
> +	struct cr0014114_led	leds[];
> +};
> +
> +static void cr0014114_calc_crc(u8 *buf, const size_t len)
> +{
> +	size_t	i;
> +	u8	crc;
> +
> +	for (i = 1, crc = 1; i < len - 1; i++)
> +		crc += buf[i];
> +	crc |= BIT(7);
> +
> +	/* special case when CRC matches to SPI commands */
> +	if (crc == CR_SET_BRIGHTNESS ||
> +	    crc == CR_INIT_REENUMERATE ||
> +	    crc == CR_NEXT_REENUMERATE)
> +		crc = 0xfe;
> +
> +	buf[len - 1] = crc;
> +}
> +
> +static int cr0014114_recount(struct cr0014114 *priv)
> +{
> +	int	ret;
> +	size_t	i;
> +	u8	cmd;
> +
> +	dev_dbg(priv->dev, "recount of LEDs is started\n");
> +
> +	do {

This do..while(0) loop isn't really required. Let's do it otherwise.

> +		cmd = CR_INIT_REENUMERATE;
> +		ret = spi_write(priv->spi, &cmd, sizeof(cmd));
> +		if (ret)
> +			break;

Please add a label out_reenum at the end of the function
and goto there from here in case of error.

> +
> +		cmd = CR_NEXT_REENUMERATE;
> +		for (i = 0; i < priv->count; i++) {
> +			msleep(CR_FW_DELAY_MSEC);
> +
> +			ret = spi_write(priv->spi, &cmd, sizeof(cmd));
> +			if (ret)
> +				break;

Similarly goto out_reenum here.

> +		}
> +	} while (0);
> +
> +	dev_dbg(priv->dev, "recount of LEDs is complete, error: %d\n", ret);
> +
> +	return ret;
> +}
> +
> +static int cr0014114_sync(struct cr0014114 *priv)
> +{
> +	int		ret;
> +	size_t		i;
> +	u8		data[priv->count + 2];

sparse is not happy about this and it causes two more problems below:

drivers/leds/leds-cr0014114.c:101:42: warning: Variable length array is
used.
drivers/leds/leds-cr0014114.c:122:42: error: cannot size expression
drivers/leds/leds-cr0014114.c:124:50: error: cannot size expression


> +	unsigned long	udelay, now = jiffies;
> +
> +	/* to avoid SPI mistiming with firmware we should wait some time */
> +	if (time_after(priv->delay, now)) {
> +		udelay = jiffies_to_usecs(priv->delay - now);
> +		usleep_range(udelay, udelay + 1);
> +	}
> +
> +	do {
> +		if (unlikely(priv->do_recount)) {
> +			ret = cr0014114_recount(priv);
> +			if (ret)
> +				break;
> +
> +			priv->do_recount = false;
> +		}
> +
> +		data[0] = CR_SET_BRIGHTNESS;
> +		for (i = 0; i < priv->count; i++)
> +			data[i + 1] = priv->leds[i].brightness;
> +		cr0014114_calc_crc(data, sizeof(data));
> +
> +		ret = spi_write(priv->spi, data, sizeof(data));
> +		if (ret)
> +			break;
> +	} while (0);
> +
> +	priv->delay = jiffies + msecs_to_jiffies(CR_FW_DELAY_MSEC);
> +
> +	return ret;
> +}
> +
> +static void cr0014114_recount_work(struct work_struct *work)
> +{
> +	int			ret;
> +	struct cr0014114	*priv = container_of(work, struct cr0014114,
> +						     work);
> +
> +	mutex_lock(&priv->lock);
> +	priv->do_recount = true;
> +	ret = cr0014114_sync(priv);
> +	mutex_unlock(&priv->lock);
> +
> +	if (ret)
> +		dev_warn(priv->dev, "recount LEDs failed %d\n", ret);
> +}
> +
> +int cr0014114_set_sync(struct led_classdev *ldev,
> +		       enum led_brightness brightness)
> +{
> +	int			ret;
> +	struct cr0014114_led    *led = container_of(ldev,
> +						    struct cr0014114_led,
> +						    ldev);
> +
> +	mutex_lock(&led->priv->lock);
> +	led->brightness = (u8)brightness;
> +	ret = cr0014114_sync(led->priv);
> +	mutex_unlock(&led->priv->lock);
> +
> +	return ret;
> +}
> +
> +void cr0014114_recount_timer(struct timer_list *t)
> +{
> +	struct cr0014114 *priv = from_timer(priv, t, timer);
> +
> +	schedule_work(&priv->work);
> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
> +}
> +
> +static int cr0014114_probe_dt(struct cr0014114 *priv)
> +{
> +	size_t			i = 0;
> +	struct cr0014114_led	*led;
> +	struct fwnode_handle	*child;
> +	struct device_node	*np;
> +	int			ret;
> +
> +	device_for_each_child_node(priv->dev, child) {
> +		np = to_of_node(child);
> +		led = &priv->leds[i];
> +
> +		ret = fwnode_property_read_string(child, "label",
> +						  &led->name);
> +		if (ret && IS_ENABLED(CONFIG_OF) && np)

The driver already depends on OF, so IS_ENABLED is redundant here.

> +			led->name = np->name;
> +
> +		if (!led->name) {
> +			fwnode_handle_put(child);
> +			return -EINVAL;
> +		}
> +
> +		fwnode_property_read_string(child, "linux,default-trigger",
> +					    &led->ldev.default_trigger);
> +
> +		led->priv			  = priv;
> +		led->ldev.name			  = led->name;
> +		led->ldev.brightness		  = LED_OFF;

This is already secured by kzalloc.

> +		led->ldev.max_brightness	  = CR_MAX_BRIGHTNESS;
> +		led->ldev.brightness_set_blocking = cr0014114_set_sync;
> +
> +		ret = devm_of_led_classdev_register(priv->dev, np,
> +						    &led->ldev);
> +		if (ret) {
> +			fwnode_handle_put(child);
> +			return ret;
> +		}
> +
> +		led->ldev.dev->of_node = np;
> +
> +		i++;
> +	}
> +
> +	return 0;
> +}
> +
> +static int cr0014114_probe(struct spi_device *spi)
> +{
> +	struct cr0014114	*priv;
> +	size_t			count;
> +	int			ret;
> +
> +	count = device_get_child_node_count(&spi->dev);
> +	if (!count) {
> +		dev_err(&spi->dev, "LEDs are not defined in device tree");
> +		return -ENODEV;
> +	}
> +
> +	priv = devm_kzalloc(&spi->dev,
> +			    sizeof(*priv) + sizeof(*priv->leds) * count,
> +			    GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	mutex_init(&priv->lock);
> +	INIT_WORK(&priv->work, cr0014114_recount_work);
> +	priv->do_recount	= true;
> +	priv->count		= count;
> +	priv->dev		= &spi->dev;
> +	priv->spi		= spi;
> +
> +	ret = cr0014114_probe_dt(priv);
> +	if (ret)
> +		return ret;
> +
> +	ret = cr0014114_sync(priv);
> +	if (ret)
> +		return ret;
> +
> +	/* setup recount timer to workaround buggy firmware */
> +	timer_setup(&priv->timer, cr0014114_recount_timer, 0);
> +	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
> +
> +	spi_set_drvdata(spi, priv);
> +
> +	return 0;
> +}
> +
> +static int cr0014114_remove(struct spi_device *spi)
> +{
> +	struct cr0014114 *priv = spi_get_drvdata(spi);
> +
> +	cancel_work_sync(&priv->work);
> +	del_timer_sync(&priv->timer);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id cr0014114_dt_ids[] = {
> +	{ .compatible = "crane,cr0014114", },
> +	{},
> +};
> +
> +MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
> +
> +static struct spi_driver cr0014114_driver = {
> +	.probe		= cr0014114_probe,
> +	.remove		= cr0014114_remove,
> +	.driver = {
> +		.name		= KBUILD_MODNAME,
> +		.of_match_table	= cr0014114_dt_ids,
> +	},
> +};
> +
> +module_spi_driver(cr0014114_driver);
> +
> +MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
> +MODULE_DESCRIPTION("cr0014114 LED driver");
> +MODULE_LICENSE("GPL");

Please add SPDX license identifier at the top of the file:
Documentation/process/license-rules.rst

> +MODULE_ALIAS("spi:cr0014114");
>

Patch

diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
new file mode 100644
index 000000000000..56721598ee81
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
@@ -0,0 +1,46 @@ 
+Crane Merchandising System - cr0014114 LED driver
+-------------------------------------------------
+
+This LED Board widely used in vending machines produced
+by Crane Merchandising Systems.
+
+Required properties:
+- compatible: "cms,cr0014114"
+- reg: chip select address for the device
+- spi-cpha: shifted clock phase mode is required
+
+LED sub-node properties:
+- label : (optional)
+	see Documentation/devicetree/bindings/leds/common.txt
+- linux,default-trigger : (optional)
+	see Documentation/devicetree/bindings/leds/common.txt
+
+Example
+-------
+
+cr0014114@0 {
+	compatible = "crane,cr0014114";
+	reg = <0>;
+	spi-max-frequency = <50000>;
+	spi-cpha;
+
+	led0 {
+		label = "cr0:red:";
+	};
+	led1 {
+		label = "cr0:green:";
+	};
+	led2 {
+		label = "cr0:blue:";
+	};
+	led3 {
+		label = "cr1:red:";
+	};
+	led4 {
+		label = "cr1:green:";
+	};
+	led5 {
+		label = "cr1:blue:";
+	};
+	...
+};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index ae850d6c0ad3..f17949c365f5 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -75,6 +75,7 @@  cnxt	Conexant Systems, Inc.
 compulab	CompuLab Ltd.
 cortina	Cortina Systems, Inc.
 cosmic	Cosmic Circuits
+crane	Crane Connectivity Solutions
 creative	Creative Technology Ltd
 crystalfontz	Crystalfontz America, Inc.
 cubietech	Cubietech, Ltd.
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 2c896c0e69e1..bb6a70ac5004 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -104,6 +104,19 @@  config LEDS_CPCAP
 	  This option enables support for LEDs offered by Motorola's
 	  CPCAP PMIC.
 
+config LEDS_CR0014114
+	tristate "LED Support for Crane CR0014114"
+	depends on LEDS_CLASS
+	depends on SPI
+	depends on OF
+	help
+	  This option enables support for CR0014114 LED Board which
+	  widely used in vending machines produced by
+	  Crane Merchandising Systems.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called leds-cr0014114.
+
 config LEDS_LM3530
 	tristate "LCD Backlight driver for LM3530"
 	depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 91eca81cae82..0176e7335994 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -78,6 +78,7 @@  obj-$(CONFIG_LEDS_MT6323)		+= leds-mt6323.o
 obj-$(CONFIG_LEDS_LM3692X)		+= leds-lm3692x.o
 
 # LED SPI Drivers
+obj-$(CONFIG_LEDS_CR0014114)		+= leds-cr0014114.o
 obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
 
 # LED Userspace Drivers
diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
new file mode 100644
index 000000000000..e3aecdbea73c
--- /dev/null
+++ b/drivers/leds/leds-cr0014114.c
@@ -0,0 +1,282 @@ 
+#include <linux/delay.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/property.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+/* CR0014114 SPI commands */
+#define CR_SET_BRIGHTNESS	0x80
+#define CR_INIT_REENUMERATE	0x81
+#define CR_NEXT_REENUMERATE	0x82
+
+/* CR0014114 default settings */
+#define CR_MAX_BRIGHTNESS	GENMASK(6, 0)
+#define CR_FW_DELAY_MSEC	10
+#define CR_RECOUNT_DELAY	(HZ * 3600)
+
+struct cr0014114_led {
+	const char		*name;
+	struct cr0014114	*priv;
+	struct led_classdev	ldev;
+	u8			brightness;
+};
+
+struct cr0014114 {
+	bool			do_recount;
+	size_t			count;
+	struct device		*dev;
+	struct mutex		lock;
+	struct spi_device	*spi;
+	struct timer_list	timer;
+	struct work_struct	work;
+	unsigned long		delay;
+	struct cr0014114_led	leds[];
+};
+
+static void cr0014114_calc_crc(u8 *buf, const size_t len)
+{
+	size_t	i;
+	u8	crc;
+
+	for (i = 1, crc = 1; i < len - 1; i++)
+		crc += buf[i];
+	crc |= BIT(7);
+
+	/* special case when CRC matches to SPI commands */
+	if (crc == CR_SET_BRIGHTNESS ||
+	    crc == CR_INIT_REENUMERATE ||
+	    crc == CR_NEXT_REENUMERATE)
+		crc = 0xfe;
+
+	buf[len - 1] = crc;
+}
+
+static int cr0014114_recount(struct cr0014114 *priv)
+{
+	int	ret;
+	size_t	i;
+	u8	cmd;
+
+	dev_dbg(priv->dev, "recount of LEDs is started\n");
+
+	do {
+		cmd = CR_INIT_REENUMERATE;
+		ret = spi_write(priv->spi, &cmd, sizeof(cmd));
+		if (ret)
+			break;
+
+		cmd = CR_NEXT_REENUMERATE;
+		for (i = 0; i < priv->count; i++) {
+			msleep(CR_FW_DELAY_MSEC);
+
+			ret = spi_write(priv->spi, &cmd, sizeof(cmd));
+			if (ret)
+				break;
+		}
+	} while (0);
+
+	dev_dbg(priv->dev, "recount of LEDs is complete, error: %d\n", ret);
+
+	return ret;
+}
+
+static int cr0014114_sync(struct cr0014114 *priv)
+{
+	int		ret;
+	size_t		i;
+	u8		data[priv->count + 2];
+	unsigned long	udelay, now = jiffies;
+
+	/* to avoid SPI mistiming with firmware we should wait some time */
+	if (time_after(priv->delay, now)) {
+		udelay = jiffies_to_usecs(priv->delay - now);
+		usleep_range(udelay, udelay + 1);
+	}
+
+	do {
+		if (unlikely(priv->do_recount)) {
+			ret = cr0014114_recount(priv);
+			if (ret)
+				break;
+
+			priv->do_recount = false;
+		}
+
+		data[0] = CR_SET_BRIGHTNESS;
+		for (i = 0; i < priv->count; i++)
+			data[i + 1] = priv->leds[i].brightness;
+		cr0014114_calc_crc(data, sizeof(data));
+
+		ret = spi_write(priv->spi, data, sizeof(data));
+		if (ret)
+			break;
+	} while (0);
+
+	priv->delay = jiffies + msecs_to_jiffies(CR_FW_DELAY_MSEC);
+
+	return ret;
+}
+
+static void cr0014114_recount_work(struct work_struct *work)
+{
+	int			ret;
+	struct cr0014114	*priv = container_of(work, struct cr0014114,
+						     work);
+
+	mutex_lock(&priv->lock);
+	priv->do_recount = true;
+	ret = cr0014114_sync(priv);
+	mutex_unlock(&priv->lock);
+
+	if (ret)
+		dev_warn(priv->dev, "recount LEDs failed %d\n", ret);
+}
+
+int cr0014114_set_sync(struct led_classdev *ldev,
+		       enum led_brightness brightness)
+{
+	int			ret;
+	struct cr0014114_led    *led = container_of(ldev,
+						    struct cr0014114_led,
+						    ldev);
+
+	mutex_lock(&led->priv->lock);
+	led->brightness = (u8)brightness;
+	ret = cr0014114_sync(led->priv);
+	mutex_unlock(&led->priv->lock);
+
+	return ret;
+}
+
+void cr0014114_recount_timer(struct timer_list *t)
+{
+	struct cr0014114 *priv = from_timer(priv, t, timer);
+
+	schedule_work(&priv->work);
+	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
+}
+
+static int cr0014114_probe_dt(struct cr0014114 *priv)
+{
+	size_t			i = 0;
+	struct cr0014114_led	*led;
+	struct fwnode_handle	*child;
+	struct device_node	*np;
+	int			ret;
+
+	device_for_each_child_node(priv->dev, child) {
+		np = to_of_node(child);
+		led = &priv->leds[i];
+
+		ret = fwnode_property_read_string(child, "label",
+						  &led->name);
+		if (ret && IS_ENABLED(CONFIG_OF) && np)
+			led->name = np->name;
+
+		if (!led->name) {
+			fwnode_handle_put(child);
+			return -EINVAL;
+		}
+
+		fwnode_property_read_string(child, "linux,default-trigger",
+					    &led->ldev.default_trigger);
+
+		led->priv			  = priv;
+		led->ldev.name			  = led->name;
+		led->ldev.brightness		  = LED_OFF;
+		led->ldev.max_brightness	  = CR_MAX_BRIGHTNESS;
+		led->ldev.brightness_set_blocking = cr0014114_set_sync;
+
+		ret = devm_of_led_classdev_register(priv->dev, np,
+						    &led->ldev);
+		if (ret) {
+			fwnode_handle_put(child);
+			return ret;
+		}
+
+		led->ldev.dev->of_node = np;
+
+		i++;
+	}
+
+	return 0;
+}
+
+static int cr0014114_probe(struct spi_device *spi)
+{
+	struct cr0014114	*priv;
+	size_t			count;
+	int			ret;
+
+	count = device_get_child_node_count(&spi->dev);
+	if (!count) {
+		dev_err(&spi->dev, "LEDs are not defined in device tree");
+		return -ENODEV;
+	}
+
+	priv = devm_kzalloc(&spi->dev,
+			    sizeof(*priv) + sizeof(*priv->leds) * count,
+			    GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	mutex_init(&priv->lock);
+	INIT_WORK(&priv->work, cr0014114_recount_work);
+	priv->do_recount	= true;
+	priv->count		= count;
+	priv->dev		= &spi->dev;
+	priv->spi		= spi;
+
+	ret = cr0014114_probe_dt(priv);
+	if (ret)
+		return ret;
+
+	ret = cr0014114_sync(priv);
+	if (ret)
+		return ret;
+
+	/* setup recount timer to workaround buggy firmware */
+	timer_setup(&priv->timer, cr0014114_recount_timer, 0);
+	mod_timer(&priv->timer, jiffies + CR_RECOUNT_DELAY);
+
+	spi_set_drvdata(spi, priv);
+
+	return 0;
+}
+
+static int cr0014114_remove(struct spi_device *spi)
+{
+	struct cr0014114 *priv = spi_get_drvdata(spi);
+
+	cancel_work_sync(&priv->work);
+	del_timer_sync(&priv->timer);
+
+	return 0;
+}
+
+static const struct of_device_id cr0014114_dt_ids[] = {
+	{ .compatible = "crane,cr0014114", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
+
+static struct spi_driver cr0014114_driver = {
+	.probe		= cr0014114_probe,
+	.remove		= cr0014114_remove,
+	.driver = {
+		.name		= KBUILD_MODNAME,
+		.of_match_table	= cr0014114_dt_ids,
+	},
+};
+
+module_spi_driver(cr0014114_driver);
+
+MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
+MODULE_DESCRIPTION("cr0014114 LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:cr0014114");