[PATCHv3,3/5] video: mx3fb: Add device tree suport.

Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: devicetree@vger.kernel.org
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Eric Bénard <eric@eukrea.com>
Signed-off-by: Denis Carikli <denis@eukrea.com>
---
ChangeLog v2->v3:
- The device tree bindings were reworked in order to make it look more like the
  IPUv3 bindings.
- The interface_pix_fmt property now looks like the IPUv3 one.
---
 .../devicetree/bindings/video/fsl,mx3-fb.txt       |   35 ++++++
 drivers/video/Kconfig                              |    2 +
 drivers/video/mx3fb.c                              |  125 +++++++++++++++++---
 3 files changed, 147 insertions(+), 15 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/video/fsl,mx3-fb.txt

On Fri, Oct 25, 2013 at 08:50:40PM +0100, Grant Likely wrote:
> On Wed, 23 Oct 2013 14:43:47 +0200, Denis Carikli <denis@eukrea.com> wrote:
> > Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
> > Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> > Cc: linux-fbdev@vger.kernel.org
> > Cc: Rob Herring <rob.herring@calxeda.com>
> > Cc: Pawel Moll <pawel.moll@arm.com>
> > Cc: Mark Rutland <mark.rutland@arm.com>
> > Cc: Stephen Warren <swarren@wwwdotorg.org>
> > Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> > Cc: devicetree@vger.kernel.org
> > Cc: Sascha Hauer <kernel@pengutronix.de>
> > Cc: linux-arm-kernel@lists.infradead.org
> > Cc: Eric Bénard <eric@eukrea.com>
> > Signed-off-by: Denis Carikli <denis@eukrea.com>
> > ---
> > ChangeLog v2->v3:
> > - The device tree bindings were reworked in order to make it look more like the
> >   IPUv3 bindings.
> > - The interface_pix_fmt property now looks like the IPUv3 one.
> > ---
> >  .../devicetree/bindings/video/fsl,mx3-fb.txt       |   35 ++++++
> >  drivers/video/Kconfig                              |    2 +
> >  drivers/video/mx3fb.c                              |  125 +++++++++++++++++---
> >  3 files changed, 147 insertions(+), 15 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> > new file mode 100644
> > index 0000000..0b31374
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> > @@ -0,0 +1,35 @@
> > +Freescale MX3 fb
> > +================
> > +
> > +Required properties:
> > +- compatible: Should be "fsl,mx3fb". compatible chips include the imx31 and the
> > +  imx35.
> > +- reg: should be register base and length as documented in the datasheet.
> > +- clocks: Handle to the ipu_gate clock.
> > +
> > +Example:
> > +
> > +lcdc: mx3fb@53fc00b4 {
> > +	compatible = "fsl,mx3-fb";
> > +	reg = <0x53fc00b4 0x0b>;
> > +	clocks = <&clks 55>;
> > +};
> 
> This (and some of the other bindings) are trivial, and they are all
> associated with a single SoC. I think it would be better to collect all
> the mx3 bindings into a single file rather than distributing them all
> over the bindings tree.
> 
> I started thinking about this after some of the DT conversations in
> Edinburgh this week. Unless there is a high likelyhood of components
> being used separately, I think it is far more useful to collect all the
> bindings for an SoC into a single file. It will certainly reduce a lot
> of the boilerplate that we've been collecting in bindings documentation
> files.
> 
> A long time ago I took that approach for the mpc5200 documentation[1].
> Take a look at that organization and let me know what you think.

I don't think this is a good idea. When a new SoC comes out we don't
know which components will be reused on the next SoC. This will cause a
lot of bikeshedding when it actually is reused and then has to be moved.

Also I would find it quite inconsistent if I had to lookup some devices
in a SoC file and most bindings in subsystem specific files. So when
searching for a binding I would first have to know if the hardware is
unique to the SoC or not.

Sascha

On Oct 23, 2013, at 7:43 AM, Denis Carikli wrote:

> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
> Cc: linux-fbdev@vger.kernel.org
> Cc: Rob Herring <rob.herring@calxeda.com>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Stephen Warren <swarren@wwwdotorg.org>
> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
> Cc: devicetree@vger.kernel.org
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: Eric Bénard <eric@eukrea.com>
> Signed-off-by: Denis Carikli <denis@eukrea.com>
> ---
> ChangeLog v2->v3:
> - The device tree bindings were reworked in order to make it look more like the
>  IPUv3 bindings.
> - The interface_pix_fmt property now looks like the IPUv3 one.
> ---
> .../devicetree/bindings/video/fsl,mx3-fb.txt       |   35 ++++++
> drivers/video/Kconfig                              |    2 +
> drivers/video/mx3fb.c                              |  125 +++++++++++++++++---
> 3 files changed, 147 insertions(+), 15 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> 
> diff --git a/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> new file mode 100644
> index 0000000..0b31374
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
> @@ -0,0 +1,35 @@
> +Freescale MX3 fb

Can you spell out framebuffer here instead of fb

> +================
> +
> +Required properties:
> +- compatible: Should be "fsl,mx3fb". compatible chips include the imx31 and the
> +  imx35.
> +- reg: should be register base and length as documented in the datasheet.
> +- clocks: Handle to the ipu_gate clock.
> +
> +Example:
> +
> +lcdc: mx3fb@53fc00b4 {
> +	compatible = "fsl,mx3-fb";
> +	reg = <0x53fc00b4 0x0b>;
> +	clocks = <&clks 55>;
> +};
> +
> +Display support
> +===============
> +Required properties:
> +- model : The user-visible name of the display.
> +
> +Optional properties:
> +- interface_pix_fmt: How this display is connected to the
> +  crtc. Currently supported types: "rgb24", "rgb565", "rgb666"


Why is there no compatible for the display?

> +
> +It can also have an optional timing subnode as described in
> +  Documentation/devicetree/bindings/video/display-timing.txt.
> +
> +Example:
> +
> +display@di0 {
> +	    interface-pix-fmt = "rgb666";
> +	    model = "CMO-QVGA";
> +};

how do you relate the display to the framebuffer?

- k

> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> index 14317b7..2a638df 100644
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -2359,6 +2359,8 @@ config FB_MX3
> 	select FB_CFB_FILLRECT
> 	select FB_CFB_COPYAREA
> 	select FB_CFB_IMAGEBLIT
> +	select VIDEOMODE_HELPERS
> +	select FB_MODE_HELPERS
> 	default y
> 	help
> 	  This is a framebuffer device for the i.MX31 LCD Controller. So
> diff --git a/drivers/video/mx3fb.c b/drivers/video/mx3fb.c
> index 804f874..de5a6c8 100644
> --- a/drivers/video/mx3fb.c
> +++ b/drivers/video/mx3fb.c
> @@ -31,6 +31,8 @@
> #include <linux/platform_data/dma-imx.h>
> #include <linux/platform_data/video-mx3fb.h>
> 
> +#include <video/of_display_timing.h>
> +
> #include <asm/io.h>
> #include <asm/uaccess.h>
> 
> @@ -757,11 +759,13 @@ static int __set_par(struct fb_info *fbi, bool lock)
> 			sig_cfg.Hsync_pol = true;
> 		if (fbi->var.sync & FB_SYNC_VERT_HIGH_ACT)
> 			sig_cfg.Vsync_pol = true;
> -		if (fbi->var.sync & FB_SYNC_CLK_INVERT)
> +		if ((fbi->var.sync & FB_SYNC_CLK_INVERT) ||
> +		    (fbi->var.sync & FB_SYNC_PIXDAT_HIGH_ACT))
> 			sig_cfg.clk_pol = true;
> 		if (fbi->var.sync & FB_SYNC_DATA_INVERT)
> 			sig_cfg.data_pol = true;
> -		if (fbi->var.sync & FB_SYNC_OE_ACT_HIGH)
> +		if ((fbi->var.sync & FB_SYNC_OE_ACT_HIGH) ||
> +		    (fbi->var.sync & FB_SYNC_DE_HIGH_ACT))
> 			sig_cfg.enable_pol = true;
> 		if (fbi->var.sync & FB_SYNC_CLK_IDLE_EN)
> 			sig_cfg.clkidle_en = true;
> @@ -1351,21 +1355,75 @@ static struct fb_info *mx3fb_init_fbinfo(struct device *dev, struct fb_ops *ops)
> 	return fbi;
> }
> 
> +static int match_dt_disp_data(const char *property)
> +{
> +	if (!strcmp("rgb666", property))
> +		return IPU_DISP_DATA_MAPPING_RGB666;
> +	else if (!strcmp("rgb565", property))
> +		return IPU_DISP_DATA_MAPPING_RGB565;
> +	else if (!strcmp("rgb24", property))
> +		return IPU_DISP_DATA_MAPPING_RGB888;
> +	else
> +		return -EINVAL;
> +}
> +
> static int init_fb_chan(struct mx3fb_data *mx3fb, struct idmac_channel *ichan)
> {
> 	struct device *dev = mx3fb->dev;
> 	struct mx3fb_platform_data *mx3fb_pdata = dev_get_platdata(dev);
> -	const char *name = mx3fb_pdata->name;
> +	struct device_node *np = dev->of_node;
> +	const char *name;
> +	const char *ipu_disp_format;
> 	unsigned int irq;
> 	struct fb_info *fbi;
> 	struct mx3fb_info *mx3fbi;
> 	const struct fb_videomode *mode;
> 	int ret, num_modes;
> +	struct fb_videomode of_mode;
> +	struct device_node *display_np, *root_np;
> +
> +	if (np) {
> +		root_np = of_find_node_by_path("/");
> +		if (!root_np) {
> +			dev_err(dev, "Can't get the \"/\" node.\n");
> +			return -EINVAL;
> +		}
> +
> +		display_np = of_find_node_by_name(root_np, "display");
> +		if (!display_np) {
> +			dev_err(dev, "Can't get the display device node.\n");
> +			return -EINVAL;
> +		}
> +
> +		of_property_read_string(display_np, "interface-pix-fmt",
> +					&ipu_disp_format);
> +		if (!ipu_disp_format) {
> +			mx3fb->disp_data_fmt = IPU_DISP_DATA_MAPPING_RGB666;
> +			dev_warn(dev,
> +				"ipu display data mapping was not defined, using the default rgb666.\n");
> +		} else {
> +			mx3fb->disp_data_fmt =
> +				match_dt_disp_data(ipu_disp_format);
> +		}
> +
> +		if (mx3fb->disp_data_fmt == -EINVAL) {
> +			dev_err(dev, "Illegal display data format \"%s\"\n",
> +				ipu_disp_format);
> +			return -EINVAL;
> +		}
> 
> -	if (mx3fb_pdata->disp_data_fmt >= ARRAY_SIZE(di_mappings)) {
> -		dev_err(dev, "Illegal display data format %d\n",
> +		of_property_read_string(display_np, "model", &name);
> +		if (ret) {
> +			dev_err(dev, "Missing display model name\n");
> +			return -EINVAL;
> +		}
> +	} else {
> +		name = mx3fb_pdata->name;
> +		if (mx3fb_pdata->disp_data_fmt >= ARRAY_SIZE(di_mappings)) {
> +			dev_err(dev, "Illegal display data format %d\n",
> 				mx3fb_pdata->disp_data_fmt);
> -		return -EINVAL;
> +			return -EINVAL;
> +		}
> 	}
> 
> 	ichan->client = mx3fb;
> @@ -1386,12 +1444,24 @@ static int init_fb_chan(struct mx3fb_data *mx3fb, struct idmac_channel *ichan)
> 		goto emode;
> 	}
> 
> -	if (mx3fb_pdata->mode && mx3fb_pdata->num_modes) {
> -		mode = mx3fb_pdata->mode;
> -		num_modes = mx3fb_pdata->num_modes;
> +	if (np) {
> +		ret = of_get_fb_videomode(display_np, &of_mode,
> +					  OF_USE_NATIVE_MODE);
> +		if (!ret) {
> +			mode = &of_mode;
> +			num_modes = 1;
> +		} else {
> +			mode = mx3fb_modedb;
> +			num_modes = ARRAY_SIZE(mx3fb_modedb);
> +		}
> 	} else {
> -		mode = mx3fb_modedb;
> -		num_modes = ARRAY_SIZE(mx3fb_modedb);
> +		if (mx3fb_pdata->mode || !mx3fb_pdata->num_modes) {
> +			mode = mx3fb_pdata->mode;
> +			num_modes = mx3fb_pdata->num_modes;
> +		} else {
> +			mode = mx3fb_modedb;
> +			num_modes = ARRAY_SIZE(mx3fb_modedb);
> +		}
> 	}
> 
> 	if (!fb_find_mode(&fbi->var, fbi, fb_mode, mode,
> @@ -1421,7 +1491,8 @@ static int init_fb_chan(struct mx3fb_data *mx3fb, struct idmac_channel *ichan)
> 	mx3fbi->mx3fb		= mx3fb;
> 	mx3fbi->blank		= FB_BLANK_NORMAL;
> 
> -	mx3fb->disp_data_fmt	= mx3fb_pdata->disp_data_fmt;
> +	if (!np)
> +		mx3fb->disp_data_fmt = mx3fb_pdata->disp_data_fmt;
> 
> 	init_completion(&mx3fbi->flip_cmpl);
> 	disable_irq(ichan->eof_irq);
> @@ -1449,13 +1520,26 @@ emode:
> 	return ret;
> }
> 
> +static int imx_dma_is_dt_ipu(struct dma_chan *chan)
> +{
> +	/* Example: 53fc0000.ipu */
> +	if (chan && chan->device && chan->device->dev) {
> +		char *name = dev_name(chan->device->dev);
> +		name = strchr(name, '.');
> +		if (name)
> +			return !strcmp(name, ".ipu");
> +	}
> +
> +	return 0;
> +}
> +
> static bool chan_filter(struct dma_chan *chan, void *arg)
> {
> 	struct dma_chan_request *rq = arg;
> 	struct device *dev;
> 	struct mx3fb_platform_data *mx3fb_pdata;
> 
> -	if (!imx_dma_is_ipu(chan))
> +	if (!imx_dma_is_ipu(chan) && !imx_dma_is_dt_ipu(chan))
> 		return false;
> 
> 	if (!rq)
> @@ -1464,8 +1548,12 @@ static bool chan_filter(struct dma_chan *chan, void *arg)
> 	dev = rq->mx3fb->dev;
> 	mx3fb_pdata = dev_get_platdata(dev);
> 
> -	return rq->id == chan->chan_id &&
> -		mx3fb_pdata->dma_dev == chan->device->dev;
> +	/* When using the devicetree, mx3fb_pdata is NULL */
> +	if (imx_dma_is_dt_ipu(chan))
> +		return rq->id == chan->chan_id;
> +	else
> +		return rq->id == chan->chan_id &&
> +			mx3fb_pdata->dma_dev == chan->device->dev;
> }
> 
> static void release_fbi(struct fb_info *fbi)
> @@ -1565,9 +1653,16 @@ static int mx3fb_remove(struct platform_device *dev)
> 	return 0;
> }
> 
> +static struct of_device_id mx3fb_of_dev_id[] = {
> +	{ .compatible = "fsl,mx3-fb", },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, mx3fb_of_dev_id);
> +
> static struct platform_driver mx3fb_driver = {
> 	.driver = {
> 		.name = MX3FB_NAME,
> +		.of_match_table = mx3fb_of_dev_id,
> 		.owner = THIS_MODULE,
> 	},
> 	.probe = mx3fb_probe,
> -- 
> 1.7.9.5
> 
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On Oct 25, 2013, at 7:18 PM, Sascha Hauer wrote:

> On Fri, Oct 25, 2013 at 08:50:40PM +0100, Grant Likely wrote:
>> On Wed, 23 Oct 2013 14:43:47 +0200, Denis Carikli <denis@eukrea.com> wrote:
>>> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
>>> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
>>> Cc: linux-fbdev@vger.kernel.org
>>> Cc: Rob Herring <rob.herring@calxeda.com>
>>> Cc: Pawel Moll <pawel.moll@arm.com>
>>> Cc: Mark Rutland <mark.rutland@arm.com>
>>> Cc: Stephen Warren <swarren@wwwdotorg.org>
>>> Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
>>> Cc: devicetree@vger.kernel.org
>>> Cc: Sascha Hauer <kernel@pengutronix.de>
>>> Cc: linux-arm-kernel@lists.infradead.org
>>> Cc: Eric Bénard <eric@eukrea.com>
>>> Signed-off-by: Denis Carikli <denis@eukrea.com>
>>> ---
>>> ChangeLog v2->v3:
>>> - The device tree bindings were reworked in order to make it look more like the
>>>  IPUv3 bindings.
>>> - The interface_pix_fmt property now looks like the IPUv3 one.
>>> ---
>>> .../devicetree/bindings/video/fsl,mx3-fb.txt       |   35 ++++++
>>> drivers/video/Kconfig                              |    2 +
>>> drivers/video/mx3fb.c                              |  125 +++++++++++++++++---
>>> 3 files changed, 147 insertions(+), 15 deletions(-)
>>> create mode 100644 Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
>>> 
>>> diff --git a/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
>>> new file mode 100644
>>> index 0000000..0b31374
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/video/fsl,mx3-fb.txt
>>> @@ -0,0 +1,35 @@
>>> +Freescale MX3 fb
>>> +================
>>> +
>>> +Required properties:
>>> +- compatible: Should be "fsl,mx3fb". compatible chips include the imx31 and the
>>> +  imx35.
>>> +- reg: should be register base and length as documented in the datasheet.
>>> +- clocks: Handle to the ipu_gate clock.
>>> +
>>> +Example:
>>> +
>>> +lcdc: mx3fb@53fc00b4 {
>>> +	compatible = "fsl,mx3-fb";
>>> +	reg = <0x53fc00b4 0x0b>;
>>> +	clocks = <&clks 55>;
>>> +};
>> 
>> This (and some of the other bindings) are trivial, and they are all
>> associated with a single SoC. I think it would be better to collect all
>> the mx3 bindings into a single file rather than distributing them all
>> over the bindings tree.
>> 
>> I started thinking about this after some of the DT conversations in
>> Edinburgh this week. Unless there is a high likelyhood of components
>> being used separately, I think it is far more useful to collect all the
>> bindings for an SoC into a single file. It will certainly reduce a lot
>> of the boilerplate that we've been collecting in bindings documentation
>> files.
>> 
>> A long time ago I took that approach for the mpc5200 documentation[1].
>> Take a look at that organization and let me know what you think.
> 
> I don't think this is a good idea. When a new SoC comes out we don't
> know which components will be reused on the next SoC. This will cause a
> lot of bikeshedding when it actually is reused and then has to be moved.
> 
> Also I would find it quite inconsistent if I had to lookup some devices
> in a SoC file and most bindings in subsystem specific files. So when
> searching for a binding I would first have to know if the hardware is
> unique to the SoC or not.

I agree that as new SoC come out its better to have these things split out.  Also for IP that is sold by vendors like Synopsys/Designware that get used on a lot of SoCs its makes it easier to ensure consistency by having the binding split out for the IP and not the SoC.

Also, by having bindings for similar devices for different SoCs kept together it becomes easier for us to see patterns across SoCs as we might come up with a more generic binding in the future.  Far more difficult if things are SoC oriented.

- k