diff mbox

[4/8] video: atmel_lcdfb: add device tree suport

Message ID 1365692422-9565-4-git-send-email-plagnioj@jcrosoft.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jean-Christophe PLAGNIOL-VILLARD April 11, 2013, 3 p.m. UTC
get display timings from device tree
Use videomode helpers to get display timings and configurations from
device tree

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Cc: linux-fbdev@vger.kernel.org
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
 .../devicetree/bindings/video/atmel,lcdc.txt       |   75 ++++++
 drivers/video/Kconfig                              |    2 +
 drivers/video/atmel_lcdfb.c                        |  244 +++++++++++++++++---
 3 files changed, 289 insertions(+), 32 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt

Comments

Nicolas Ferre April 16, 2013, 1:42 p.m. UTC | #1
On 04/11/2013 05:00 PM, Jean-Christophe PLAGNIOL-VILLARD :
> get display timings from device tree
> Use videomode helpers to get display timings and configurations from
> device tree

2 sentences? Simply elaborate the 2nd one and it will be good.

> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> Cc: linux-fbdev@vger.kernel.org
> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> ---
>  .../devicetree/bindings/video/atmel,lcdc.txt       |   75 ++++++
>  drivers/video/Kconfig                              |    2 +
>  drivers/video/atmel_lcdfb.c                        |  244 +++++++++++++++++---
>  3 files changed, 289 insertions(+), 32 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt
> 
> diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
> new file mode 100644
> index 0000000..1ec175e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt

Why lcdc? I would have preferred atmel,lcdfb, like the driver's name: it
is even more self-explanatory...

> @@ -0,0 +1,75 @@
> +Atmel LCDC Framebuffer
> +-----------------------------------------------------
> +
> +Required properties:
> +- compatible :
> +	"atmel,at91sam9261-lcdc" , 
> +	"atmel,at91sam9263-lcdc" ,
> +	"atmel,at91sam9g10-lcdc" ,
> +	"atmel,at91sam9g45-lcdc" ,
> +	"atmel,at91sam9g45es-lcdc" ,
> +	"atmel,at91sam9rl-lcdc" ,
> +	"atmel,at32ap-lcdc"
> +- reg : Should contain 1 register ranges(address and length)
> +- interrupts : framebuffer controller interrupt
> +- display: a phandle pointing to the display node
> +
> +Required nodes:
> +- display: a display node is required to initialize the lcd panel
> +	This should be in the board dts.
> +- default-mode: a videomode within the display with timing parameters
> +	as specified below.
> +
> +Example:
> +
> +	fb0: fb@0x00500000 {
> +		compatible = "atmel,at91sam9g45-lcdc";
> +		reg = <0x00500000 0x1000>;
> +		interrupts = <23 3 0>;
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&pinctrl_fb>;
> +		display = <&display0>;
> +		status = "okay";
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +
> +	};
> +
> +Atmel LCDC Display
> +-----------------------------------------------------
> +Required properties (as per of_videomode_helper):

Can you please point somewhere to the documentation:
Documentation/devicetree/bindings/video/display-timing.txt

> + - atmel,dmacon: dma controler configuration

Typo: controller.

> + - atmel,lcdcon2: lcd controler configuration

Ditto

> + - atmel,guard-time: lcd guard time (Delay in frame periods)

periods -> period, no?

> + - bits-per-pixel: lcd panel bit-depth.
> +
> +Optional properties (as per of_videomode_helper):
> + - atmel,lcdcon-backlight: enable backlight
> + - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"

Is it a sting, or a number (as seen below)? If it is a number, please
tell how to choose the index.


> + - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
> +
> +Example:
> +	display0: display {
> +		bits-per-pixel = <32>;
> +		atmel,lcdcon-backlight;
> +		atmel,dmacon = <0x1>;
> +		atmel,lcdcon2 = <0x80008002>;
> +		atmel,guard-time = <9>;
> +		atmel,lcd-wiring-mode = <1>;
> +
> +		display-timings {
> +			native-mode = <&timing0>;
> +			timing0: timing0 {
> +				clock-frequency = <9000000>;
> +				hactive = <480>;
> +				vactive = <272>;
> +				hback-porch = <1>;
> +				hfront-porch = <1>;
> +				vback-porch = <40>;
> +				vfront-porch = <1>;
> +				hsync-len = <45>;
> +				vsync-len = <1>;
> +			};
> +		};
> +	};
> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> index 4c1546f..0687482 100644
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -1018,6 +1018,8 @@ config FB_ATMEL
>  	select FB_CFB_FILLRECT
>  	select FB_CFB_COPYAREA
>  	select FB_CFB_IMAGEBLIT
> +	select FB_MODE_HELPERS
> +	select OF_VIDEOMODE
>  	help
>  	  This enables support for the AT91/AT32 LCD Controller.
>  
> diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
> index f67e226..4a31570 100644
> --- a/drivers/video/atmel_lcdfb.c
> +++ b/drivers/video/atmel_lcdfb.c
> @@ -20,7 +20,11 @@
>  #include <linux/gfp.h>
>  #include <linux/module.h>
>  #include <linux/platform_data/atmel.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
>  #include <video/of_display_timing.h>

As said in patch 1/8, this one belongs to this 4/8 patch.

> +#include <video/videomode.h>
>  
>  #include <mach/cpu.h>
>  #include <asm/gpio.h>
> @@ -59,6 +63,13 @@ struct atmel_lcdfb_info {
>  	struct atmel_lcdfb_config *config;
>  };
>  
> +struct atmel_lcdfb_power_ctrl_gpio {
> +	int gpio;
> +	int active_low;
> +
> +	struct list_head list;
> +};
> +
>  #define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
>  #define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))
>  
> @@ -945,16 +956,187 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
>  	clk_disable(sinfo->lcdc_clk);
>  }
>  
> +#ifdef CONFIG_OF
> +static const struct of_device_id atmel_lcdfb_dt_ids[] = {
> +	{ .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
> +	{ .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
> +	{ .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
> +	{ .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
> +	{ .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
> +	{ .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
> +	{ .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
> +	{ /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
> +
> +static const char *atmel_lcdfb_wiring_modes[] = {
> +	[ATMEL_LCDC_WIRING_BGR]	= "BRG",
> +	[ATMEL_LCDC_WIRING_RGB]	= "RGB",
> +};
> +
> +const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
> +{
> +	const char *mode;
> +	int err, i;
> +
> +	err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
> +	if (err < 0)
> +		return ATMEL_LCDC_WIRING_BGR;
> +
> +	for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
> +		if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
> +			return i;
> +
> +	return -ENODEV;
> +}
> +
> +static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
> +{
> +	struct atmel_lcdfb_power_ctrl_gpio *og;
> +
> +	list_for_each_entry(og, &pdata->pwr_gpios, list)
> +		gpio_set_value(og->gpio, on);
> +}
> +
> +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
> +{
> +	struct fb_info *info = sinfo->info;
> +	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
> +	struct fb_var_screeninfo *var = &info->var;
> +	struct device *dev = &sinfo->pdev->dev;
> +	struct device_node *np =dev->of_node;
> +	struct device_node *display_np;
> +	struct device_node *timings_np;
> +	struct display_timings *timings;
> +	enum of_gpio_flags flags;
> +	struct atmel_lcdfb_power_ctrl_gpio *og;
> +	bool is_gpio_power = false;
> +	int ret = -ENOENT;
> +	int i, gpio;
> +
> +	sinfo->config = (struct atmel_lcdfb_config*)
> +		of_match_device(atmel_lcdfb_dt_ids, dev)->data;

Please split it in 2 steps, otherwise the day that the drivers doesn't
find the device in dt_ids table, it hangs here with an Oops.

> +
> +	display_np = of_parse_phandle(np, "display", 0);
> +	if (!display_np) {
> +		dev_err(dev, "failed to find display phandle\n");
> +		return -ENOENT;
> +	}
> +
> +	ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get property bits-per-pixel\n");
> +		goto put_display_node;
> +	}
> +
> +	ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get property atmel,guard-time\n");
> +		goto put_display_node;
> +	}
> +
> +	ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get property atmel,lcdcon2\n");
> +		goto put_display_node;
> +	}
> +
> +	ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
> +	if (ret < 0) {
> +		dev_err(dev, "failed to get property bits-per-pixel\n");

No, wrong error message.

> +		goto put_display_node;
> +	}
> +
> +	ret = -ENOMEM;
> +	for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
> +		gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
> +					       i, &flags);
> +		if (gpio < 0)
> +			continue;
> +
> +		og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
> +		if (!og)
> +			goto put_display_node;
> +
> +		og->gpio = gpio;
> +		og->active_low = flags & OF_GPIO_ACTIVE_LOW;
> +		is_gpio_power = true;
> +		ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
> +		if (ret) {
> +			dev_err(dev, "request gpio %d failed\n", gpio);
> +			goto put_display_node;
> +		}
> +
> +		ret = gpio_direction_output(gpio, og->active_low);
> +		if (ret) {
> +			dev_err(dev, "set direction output gpio %d failed\n", gpio);
> +			goto put_display_node;
> +		}
> +	}
> +
> +	if (is_gpio_power)
> +		pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
> +
> +	ret = atmel_lcdfb_get_of_wiring_modes(display_np);
> +	if (ret < 0) {
> +		dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
> +		goto put_display_node;
> +	}
> +	pdata->lcd_wiring_mode = ret;
> +
> +	pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
> +
> +	timings = of_get_display_timings(display_np);
> +	if (!timings) {
> +		dev_err(dev, "failed to get display timings\n");
> +		goto put_display_node;
> +	}
> +
> +	timings_np = of_find_node_by_name(display_np, "display-timings");
> +	if (!timings_np) {
> +		dev_err(dev, "failed to find display-timings node\n");
> +		goto put_display_node;
> +	}
> +
> +	for (i = 0; i < of_get_child_count(timings_np); i++) {
> +		struct videomode vm;
> +		struct fb_videomode fb_vm;
> +
> +		ret = videomode_from_timing(timings, &vm, i);
> +		if (ret < 0)
> +			goto put_timings_node;
> +		ret = fb_videomode_from_videomode(&vm, &fb_vm);
> +		if (ret < 0)
> +			goto put_timings_node;
> +
> +		fb_add_videomode(&fb_vm, &info->modelist);
> +	}
> +
> +	return 0;
> +
> +put_timings_node:
> +	of_node_put(timings_np);
> +put_display_node:
> +	of_node_put(display_np);
> +	return ret;
> +}
> +#else
> +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
> +{
> +	return 0;
> +}
> +#endif
>  
>  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct fb_info *info;
>  	struct atmel_lcdfb_info *sinfo;
> -	struct atmel_lcdfb_pdata *pdata;
> -	struct fb_videomode fbmode;
> +	struct atmel_lcdfb_pdata *pdata = NULL;
>  	struct resource *regs = NULL;
>  	struct resource *map = NULL;
> +	struct fb_modelist *modelist;
>  	int ret;
>  
>  	dev_dbg(dev, "%s BEGIN\n", __func__);
> @@ -967,17 +1149,35 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  	}
>  
>  	sinfo = info->par;
> +	sinfo->pdev = pdev;
> +	sinfo->info = info;
> +
> +	INIT_LIST_HEAD(&info->modelist);
>  
> -	if (dev->platform_data) {
> -		pdata = (struct atmel_lcdfb_pdata *)dev->platform_data;
> +	if (pdev->dev.of_node) {
> +		ret = atmel_lcdfb_of_init(sinfo);
> +		if (ret)
> +			goto free_info;
> +	} else if (dev->platform_data) {
> +		struct fb_monspecs *monspecs;
> +		int i;
> +
> +		pdata = dev->platform_data;
> +		monspecs = pdata->default_monspecs;
>  		sinfo->pdata = *pdata;
> +
> +		for (i = 0; i < monspecs->modedb_len; i++)
> +			fb_add_videomode(&monspecs->modedb[i], &info->modelist);
> +
> +		sinfo->config = atmel_lcdfb_get_config(pdev);
> +
> +		info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
> +		memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
>  	} else {
>  		dev_err(dev, "cannot get default configuration\n");
>  		goto free_info;
>  	}
> -	sinfo->info = info;
> -	sinfo->pdev = pdev;
> -	sinfo->config = atmel_lcdfb_get_config(pdev);
> +
>  	if (!sinfo->config)
>  		goto free_info;
>  
> @@ -986,7 +1186,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  	info->pseudo_palette = sinfo->pseudo_palette;
>  	info->fbops = &atmel_lcdfb_ops;
>  
> -	memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
>  	info->fix = atmel_lcdfb_fix;
>  
>  	/* Enable LCDC Clocks */
> @@ -1002,14 +1201,11 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  	}
>  	atmel_lcdfb_start_clock(sinfo);
>  
> -	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
> -			info->monspecs.modedb_len, info->monspecs.modedb,
> -			pdata->default_bpp);
> -	if (!ret) {
> -		dev_err(dev, "no suitable video mode found\n");
> -		goto stop_clk;
> -	}
> +	modelist = list_first_entry(&info->modelist,
> +			struct fb_modelist, list);
> +	fb_videomode_to_var(&info->var, &modelist->mode);
>  
> +	atmel_lcdfb_check_var(&info->var, info);
>  
>  	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	if (!regs) {
> @@ -1093,18 +1289,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  		goto unregister_irqs;
>  	}
>  
> -	/*
> -	 * This makes sure that our colour bitfield
> -	 * descriptors are correctly initialised.
> -	 */
> -	atmel_lcdfb_check_var(&info->var, info);
> -
> -	ret = fb_set_var(info, &info->var);
> -	if (ret) {
> -		dev_warn(dev, "unable to set display parameters\n");
> -		goto free_cmap;
> -	}
> -
>  	dev_set_drvdata(dev, info);
>  
>  	/*
> @@ -1116,10 +1300,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  		goto reset_drvdata;
>  	}
>  
> -	/* add selected videomode to modelist */
> -	fb_var_to_videomode(&fbmode, &info->var);
> -	fb_add_videomode(&fbmode, &info->modelist);
> -
>  	/* Power up the LCDC screen */
>  	atmel_lcdfb_power_control(sinfo, 1);
>  
> @@ -1130,7 +1310,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  
>  reset_drvdata:
>  	dev_set_drvdata(dev, NULL);
> -free_cmap:
>  	fb_dealloc_cmap(&info->cmap);
>  unregister_irqs:
>  	cancel_work_sync(&sinfo->task);
> @@ -1249,6 +1428,7 @@ static struct platform_driver atmel_lcdfb_driver = {
>  	.driver		= {
>  		.name	= "atmel_lcdfb",
>  		.owner	= THIS_MODULE,
> +		.of_match_table	= of_match_ptr(atmel_lcdfb_dt_ids),
>  	},
>  };
>  
>
Jean-Christophe PLAGNIOL-VILLARD April 16, 2013, 1:44 p.m. UTC | #2
On 15:42 Tue 16 Apr     , Nicolas Ferre wrote:
> On 04/11/2013 05:00 PM, Jean-Christophe PLAGNIOL-VILLARD :
> > get display timings from device tree
> > Use videomode helpers to get display timings and configurations from
> > device tree
> 
> 2 sentences? Simply elaborate the 2nd one and it will be good.
> 
> > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> > Cc: linux-fbdev@vger.kernel.org
> > Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
> > Cc: Andrew Morton <akpm@linux-foundation.org>
> > ---
> >  .../devicetree/bindings/video/atmel,lcdc.txt       |   75 ++++++
> >  drivers/video/Kconfig                              |    2 +
> >  drivers/video/atmel_lcdfb.c                        |  244 +++++++++++++++++---
> >  3 files changed, 289 insertions(+), 32 deletions(-)
> >  create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
> > new file mode 100644
> > index 0000000..1ec175e
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
> 
> Why lcdc? I would have preferred atmel,lcdfb, like the driver's name: it
> is even more self-explanatory...
we do not describe drivers but IP
> 
> > @@ -0,0 +1,75 @@
> > +Atmel LCDC Framebuffer
> > +-----------------------------------------------------
> > +
> > +Required properties:
> > +- compatible :
> > +	"atmel,at91sam9261-lcdc" , 
> > +	"atmel,at91sam9263-lcdc" ,
> > +	"atmel,at91sam9g10-lcdc" ,
> > +	"atmel,at91sam9g45-lcdc" ,
> > +	"atmel,at91sam9g45es-lcdc" ,
> > +	"atmel,at91sam9rl-lcdc" ,
> > +	"atmel,at32ap-lcdc"
> > +- reg : Should contain 1 register ranges(address and length)
> > +- interrupts : framebuffer controller interrupt
> > +- display: a phandle pointing to the display node
> > +
> > +Required nodes:
> > +- display: a display node is required to initialize the lcd panel
> > +	This should be in the board dts.
> > +- default-mode: a videomode within the display with timing parameters
> > +	as specified below.
> > +
> > +Example:
> > +
> > +	fb0: fb@0x00500000 {
> > +		compatible = "atmel,at91sam9g45-lcdc";
> > +		reg = <0x00500000 0x1000>;
> > +		interrupts = <23 3 0>;
> > +		pinctrl-names = "default";
> > +		pinctrl-0 = <&pinctrl_fb>;
> > +		display = <&display0>;
> > +		status = "okay";
> > +		#address-cells = <1>;
> > +		#size-cells = <1>;
> > +
> > +	};
> > +
> > +Atmel LCDC Display
> > +-----------------------------------------------------
> > +Required properties (as per of_videomode_helper):
> 
> Can you please point somewhere to the documentation:
> Documentation/devicetree/bindings/video/display-timing.txt
> 
> > + - atmel,dmacon: dma controler configuration
> 
> Typo: controller.
> 
> > + - atmel,lcdcon2: lcd controler configuration
> 
> Ditto
> 
> > + - atmel,guard-time: lcd guard time (Delay in frame periods)
> 
> periods -> period, no?
no it's periods even in the datasheet
> 
> > + - bits-per-pixel: lcd panel bit-depth.
> > +
> > +Optional properties (as per of_videomode_helper):
> > + - atmel,lcdcon-backlight: enable backlight
> > + - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"
> 
> Is it a sting, or a number (as seen below)? If it is a number, please
> tell how to choose the index.
String
> 
> 
> > + - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
> > +
> > +Example:
> > +	display0: display {
> > +		bits-per-pixel = <32>;
> > +		atmel,lcdcon-backlight;
> > +		atmel,dmacon = <0x1>;
> > +		atmel,lcdcon2 = <0x80008002>;
> > +		atmel,guard-time = <9>;
> > +		atmel,lcd-wiring-mode = <1>;
> > +
> > +		display-timings {
> > +			native-mode = <&timing0>;
> > +			timing0: timing0 {
> > +				clock-frequency = <9000000>;
> > +				hactive = <480>;
> > +				vactive = <272>;
> > +				hback-porch = <1>;
> > +				hfront-porch = <1>;
> > +				vback-porch = <40>;
> > +				vfront-porch = <1>;
> > +				hsync-len = <45>;
> > +				vsync-len = <1>;
> > +			};
> > +		};
> > +	};
> > diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> > index 4c1546f..0687482 100644
> > --- a/drivers/video/Kconfig
> > +++ b/drivers/video/Kconfig
> > @@ -1018,6 +1018,8 @@ config FB_ATMEL
> >  	select FB_CFB_FILLRECT
> >  	select FB_CFB_COPYAREA
> >  	select FB_CFB_IMAGEBLIT
> > +	select FB_MODE_HELPERS
> > +	select OF_VIDEOMODE
> >  	help
> >  	  This enables support for the AT91/AT32 LCD Controller.
> >  
> > diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
> > index f67e226..4a31570 100644
> > --- a/drivers/video/atmel_lcdfb.c
> > +++ b/drivers/video/atmel_lcdfb.c
> > @@ -20,7 +20,11 @@
> >  #include <linux/gfp.h>
> >  #include <linux/module.h>
> >  #include <linux/platform_data/atmel.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_gpio.h>
> >  #include <video/of_display_timing.h>
> 
> As said in patch 1/8, this one belongs to this 4/8 patch.
> 
> > +#include <video/videomode.h>
> >  
> >  #include <mach/cpu.h>
> >  #include <asm/gpio.h>
> > @@ -59,6 +63,13 @@ struct atmel_lcdfb_info {
> >  	struct atmel_lcdfb_config *config;
> >  };
> >  
> > +struct atmel_lcdfb_power_ctrl_gpio {
> > +	int gpio;
> > +	int active_low;
> > +
> > +	struct list_head list;
> > +};
> > +
> >  #define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
> >  #define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))
> >  
> > @@ -945,16 +956,187 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
> >  	clk_disable(sinfo->lcdc_clk);
> >  }
> >  
> > +#ifdef CONFIG_OF
> > +static const struct of_device_id atmel_lcdfb_dt_ids[] = {
> > +	{ .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
> > +	{ .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
> > +	{ .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
> > +	{ .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
> > +	{ .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
> > +	{ .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
> > +	{ .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
> > +	{ /* sentinel */ }
> > +};
> > +
> > +MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
> > +
> > +static const char *atmel_lcdfb_wiring_modes[] = {
> > +	[ATMEL_LCDC_WIRING_BGR]	= "BRG",
> > +	[ATMEL_LCDC_WIRING_RGB]	= "RGB",
> > +};
> > +
> > +const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
> > +{
> > +	const char *mode;
> > +	int err, i;
> > +
> > +	err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
> > +	if (err < 0)
> > +		return ATMEL_LCDC_WIRING_BGR;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
> > +		if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
> > +			return i;
> > +
> > +	return -ENODEV;
> > +}
> > +
> > +static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
> > +{
> > +	struct atmel_lcdfb_power_ctrl_gpio *og;
> > +
> > +	list_for_each_entry(og, &pdata->pwr_gpios, list)
> > +		gpio_set_value(og->gpio, on);
> > +}
> > +
> > +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
> > +{
> > +	struct fb_info *info = sinfo->info;
> > +	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
> > +	struct fb_var_screeninfo *var = &info->var;
> > +	struct device *dev = &sinfo->pdev->dev;
> > +	struct device_node *np =dev->of_node;
> > +	struct device_node *display_np;
> > +	struct device_node *timings_np;
> > +	struct display_timings *timings;
> > +	enum of_gpio_flags flags;
> > +	struct atmel_lcdfb_power_ctrl_gpio *og;
> > +	bool is_gpio_power = false;
> > +	int ret = -ENOENT;
> > +	int i, gpio;
> > +
> > +	sinfo->config = (struct atmel_lcdfb_config*)
> > +		of_match_device(atmel_lcdfb_dt_ids, dev)->data;
> 
> Please split it in 2 steps, otherwise the day that the drivers doesn't
> find the device in dt_ids table, it hangs here with an Oops.
no as you will never end here in this case
> 
> > +
> > +	display_np = of_parse_phandle(np, "display", 0);
> > +	if (!display_np) {
> > +		dev_err(dev, "failed to find display phandle\n");
> > +		return -ENOENT;
> > +	}
> > +
> > +	ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
> > +	if (ret < 0) {
> > +		dev_err(dev, "failed to get property bits-per-pixel\n");
> > +		goto put_display_node;
> > +	}
> > +
> > +	ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
> > +	if (ret < 0) {
> > +		dev_err(dev, "failed to get property atmel,guard-time\n");
> > +		goto put_display_node;
> > +	}
> > +
> > +	ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
> > +	if (ret < 0) {
> > +		dev_err(dev, "failed to get property atmel,lcdcon2\n");
> > +		goto put_display_node;
> > +	}
> > +
> > +	ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
> > +	if (ret < 0) {
> > +		dev_err(dev, "failed to get property bits-per-pixel\n");
> 
> No, wrong error message.
> 
> > +		goto put_display_node;
> > +	}
> > +
> > +	ret = -ENOMEM;
> > +	for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
> > +		gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
> > +					       i, &flags);
> > +		if (gpio < 0)
> > +			continue;
> > +
> > +		og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
> > +		if (!og)
> > +			goto put_display_node;
> > +
> > +		og->gpio = gpio;
> > +		og->active_low = flags & OF_GPIO_ACTIVE_LOW;
> > +		is_gpio_power = true;
> > +		ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
> > +		if (ret) {
> > +			dev_err(dev, "request gpio %d failed\n", gpio);
> > +			goto put_display_node;
> > +		}
> > +
> > +		ret = gpio_direction_output(gpio, og->active_low);
> > +		if (ret) {
> > +			dev_err(dev, "set direction output gpio %d failed\n", gpio);
> > +			goto put_display_node;
> > +		}
> > +	}
> > +
> > +	if (is_gpio_power)
> > +		pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
> > +
> > +	ret = atmel_lcdfb_get_of_wiring_modes(display_np);
> > +	if (ret < 0) {
> > +		dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
> > +		goto put_display_node;
> > +	}
> > +	pdata->lcd_wiring_mode = ret;
> > +
> > +	pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
> > +
> > +	timings = of_get_display_timings(display_np);
> > +	if (!timings) {
> > +		dev_err(dev, "failed to get display timings\n");
> > +		goto put_display_node;
> > +	}
> > +
> > +	timings_np = of_find_node_by_name(display_np, "display-timings");
> > +	if (!timings_np) {
> > +		dev_err(dev, "failed to find display-timings node\n");
> > +		goto put_display_node;
> > +	}
> > +
> > +	for (i = 0; i < of_get_child_count(timings_np); i++) {
> > +		struct videomode vm;
> > +		struct fb_videomode fb_vm;
> > +
> > +		ret = videomode_from_timing(timings, &vm, i);
> > +		if (ret < 0)
> > +			goto put_timings_node;
> > +		ret = fb_videomode_from_videomode(&vm, &fb_vm);
> > +		if (ret < 0)
> > +			goto put_timings_node;
> > +
> > +		fb_add_videomode(&fb_vm, &info->modelist);
> > +	}
> > +
> > +	return 0;
> > +
> > +put_timings_node:
> > +	of_node_put(timings_np);
> > +put_display_node:
> > +	of_node_put(display_np);
> > +	return ret;
> > +}
> > +#else
> > +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
> > +{
> > +	return 0;
> > +}
> > +#endif
> >  
> >  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  {
> >  	struct device *dev = &pdev->dev;
> >  	struct fb_info *info;
> >  	struct atmel_lcdfb_info *sinfo;
> > -	struct atmel_lcdfb_pdata *pdata;
> > -	struct fb_videomode fbmode;
> > +	struct atmel_lcdfb_pdata *pdata = NULL;
> >  	struct resource *regs = NULL;
> >  	struct resource *map = NULL;
> > +	struct fb_modelist *modelist;
> >  	int ret;
> >  
> >  	dev_dbg(dev, "%s BEGIN\n", __func__);
> > @@ -967,17 +1149,35 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  	}
> >  
> >  	sinfo = info->par;
> > +	sinfo->pdev = pdev;
> > +	sinfo->info = info;
> > +
> > +	INIT_LIST_HEAD(&info->modelist);
> >  
> > -	if (dev->platform_data) {
> > -		pdata = (struct atmel_lcdfb_pdata *)dev->platform_data;
> > +	if (pdev->dev.of_node) {
> > +		ret = atmel_lcdfb_of_init(sinfo);
> > +		if (ret)
> > +			goto free_info;
> > +	} else if (dev->platform_data) {
> > +		struct fb_monspecs *monspecs;
> > +		int i;
> > +
> > +		pdata = dev->platform_data;
> > +		monspecs = pdata->default_monspecs;
> >  		sinfo->pdata = *pdata;
> > +
> > +		for (i = 0; i < monspecs->modedb_len; i++)
> > +			fb_add_videomode(&monspecs->modedb[i], &info->modelist);
> > +
> > +		sinfo->config = atmel_lcdfb_get_config(pdev);
> > +
> > +		info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
> > +		memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
> >  	} else {
> >  		dev_err(dev, "cannot get default configuration\n");
> >  		goto free_info;
> >  	}
> > -	sinfo->info = info;
> > -	sinfo->pdev = pdev;
> > -	sinfo->config = atmel_lcdfb_get_config(pdev);
> > +
> >  	if (!sinfo->config)
> >  		goto free_info;
> >  
> > @@ -986,7 +1186,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  	info->pseudo_palette = sinfo->pseudo_palette;
> >  	info->fbops = &atmel_lcdfb_ops;
> >  
> > -	memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
> >  	info->fix = atmel_lcdfb_fix;
> >  
> >  	/* Enable LCDC Clocks */
> > @@ -1002,14 +1201,11 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  	}
> >  	atmel_lcdfb_start_clock(sinfo);
> >  
> > -	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
> > -			info->monspecs.modedb_len, info->monspecs.modedb,
> > -			pdata->default_bpp);
> > -	if (!ret) {
> > -		dev_err(dev, "no suitable video mode found\n");
> > -		goto stop_clk;
> > -	}
> > +	modelist = list_first_entry(&info->modelist,
> > +			struct fb_modelist, list);
> > +	fb_videomode_to_var(&info->var, &modelist->mode);
> >  
> > +	atmel_lcdfb_check_var(&info->var, info);
> >  
> >  	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >  	if (!regs) {
> > @@ -1093,18 +1289,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  		goto unregister_irqs;
> >  	}
> >  
> > -	/*
> > -	 * This makes sure that our colour bitfield
> > -	 * descriptors are correctly initialised.
> > -	 */
> > -	atmel_lcdfb_check_var(&info->var, info);
> > -
> > -	ret = fb_set_var(info, &info->var);
> > -	if (ret) {
> > -		dev_warn(dev, "unable to set display parameters\n");
> > -		goto free_cmap;
> > -	}
> > -
> >  	dev_set_drvdata(dev, info);
> >  
> >  	/*
> > @@ -1116,10 +1300,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  		goto reset_drvdata;
> >  	}
> >  
> > -	/* add selected videomode to modelist */
> > -	fb_var_to_videomode(&fbmode, &info->var);
> > -	fb_add_videomode(&fbmode, &info->modelist);
> > -
> >  	/* Power up the LCDC screen */
> >  	atmel_lcdfb_power_control(sinfo, 1);
> >  
> > @@ -1130,7 +1310,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
> >  
> >  reset_drvdata:
> >  	dev_set_drvdata(dev, NULL);
> > -free_cmap:
> >  	fb_dealloc_cmap(&info->cmap);
> >  unregister_irqs:
> >  	cancel_work_sync(&sinfo->task);
> > @@ -1249,6 +1428,7 @@ static struct platform_driver atmel_lcdfb_driver = {
> >  	.driver		= {
> >  		.name	= "atmel_lcdfb",
> >  		.owner	= THIS_MODULE,
> > +		.of_match_table	= of_match_ptr(atmel_lcdfb_dt_ids),
> >  	},
> >  };
> >  
> > 
> 
> 
> -- 
> Nicolas Ferre
Nicolas Ferre April 16, 2013, 3:43 p.m. UTC | #3
On 04/16/2013 03:44 PM, Jean-Christophe PLAGNIOL-VILLARD :
> On 15:42 Tue 16 Apr     , Nicolas Ferre wrote:
>> On 04/11/2013 05:00 PM, Jean-Christophe PLAGNIOL-VILLARD :
>>> get display timings from device tree
>>> Use videomode helpers to get display timings and configurations from
>>> device tree
>>
>> 2 sentences? Simply elaborate the 2nd one and it will be good.
>>
>>> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
>>> Cc: linux-fbdev@vger.kernel.org
>>> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
>>> Cc: Andrew Morton <akpm@linux-foundation.org>
>>> ---
>>>  .../devicetree/bindings/video/atmel,lcdc.txt       |   75 ++++++
>>>  drivers/video/Kconfig                              |    2 +
>>>  drivers/video/atmel_lcdfb.c                        |  244 +++++++++++++++++---
>>>  3 files changed, 289 insertions(+), 32 deletions(-)
>>>  create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
>>> new file mode 100644
>>> index 0000000..1ec175e
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
>>
>> Why lcdc? I would have preferred atmel,lcdfb, like the driver's name: it
>> is even more self-explanatory...
> we do not describe drivers but IP

fine, but in
static const struct platform_device_id atmel_lcdfb_devtypes, we use
"xxx-lcdfb" type...

>>
>>> @@ -0,0 +1,75 @@
>>> +Atmel LCDC Framebuffer
>>> +-----------------------------------------------------
>>> +
>>> +Required properties:
>>> +- compatible :
>>> +	"atmel,at91sam9261-lcdc" , 
>>> +	"atmel,at91sam9263-lcdc" ,
>>> +	"atmel,at91sam9g10-lcdc" ,
>>> +	"atmel,at91sam9g45-lcdc" ,
>>> +	"atmel,at91sam9g45es-lcdc" ,
>>> +	"atmel,at91sam9rl-lcdc" ,
>>> +	"atmel,at32ap-lcdc"
>>> +- reg : Should contain 1 register ranges(address and length)
>>> +- interrupts : framebuffer controller interrupt
>>> +- display: a phandle pointing to the display node
>>> +
>>> +Required nodes:
>>> +- display: a display node is required to initialize the lcd panel
>>> +	This should be in the board dts.
>>> +- default-mode: a videomode within the display with timing parameters
>>> +	as specified below.
>>> +
>>> +Example:
>>> +
>>> +	fb0: fb@0x00500000 {
>>> +		compatible = "atmel,at91sam9g45-lcdc";
>>> +		reg = <0x00500000 0x1000>;
>>> +		interrupts = <23 3 0>;
>>> +		pinctrl-names = "default";
>>> +		pinctrl-0 = <&pinctrl_fb>;
>>> +		display = <&display0>;
>>> +		status = "okay";
>>> +		#address-cells = <1>;
>>> +		#size-cells = <1>;
>>> +
>>> +	};
>>> +
>>> +Atmel LCDC Display
>>> +-----------------------------------------------------
>>> +Required properties (as per of_videomode_helper):
>>
>> Can you please point somewhere to the documentation:
>> Documentation/devicetree/bindings/video/display-timing.txt
>>
>>> + - atmel,dmacon: dma controler configuration
>>
>> Typo: controller.
>>
>>> + - atmel,lcdcon2: lcd controler configuration
>>
>> Ditto
>>
>>> + - atmel,guard-time: lcd guard time (Delay in frame periods)
>>
>> periods -> period, no?
> no it's periods even in the datasheet
>>
>>> + - bits-per-pixel: lcd panel bit-depth.
>>> +
>>> +Optional properties (as per of_videomode_helper):
>>> + - atmel,lcdcon-backlight: enable backlight
>>> + - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"
>>
>> Is it a sting, or a number (as seen below)? If it is a number, please
>> tell how to choose the index.
> String

Okay: so tell it in the description and correct the example below.


>>> + - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
>>> +
>>> +Example:
>>> +	display0: display {
>>> +		bits-per-pixel = <32>;
>>> +		atmel,lcdcon-backlight;
>>> +		atmel,dmacon = <0x1>;
>>> +		atmel,lcdcon2 = <0x80008002>;
>>> +		atmel,guard-time = <9>;
>>> +		atmel,lcd-wiring-mode = <1>;

Here ----------------------------------^^^^

>>> +
>>> +		display-timings {
>>> +			native-mode = <&timing0>;
>>> +			timing0: timing0 {
>>> +				clock-frequency = <9000000>;
>>> +				hactive = <480>;
>>> +				vactive = <272>;
>>> +				hback-porch = <1>;
>>> +				hfront-porch = <1>;
>>> +				vback-porch = <40>;
>>> +				vfront-porch = <1>;
>>> +				hsync-len = <45>;
>>> +				vsync-len = <1>;
>>> +			};
>>> +		};
>>> +	};
>>> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
>>> index 4c1546f..0687482 100644
>>> --- a/drivers/video/Kconfig
>>> +++ b/drivers/video/Kconfig
>>> @@ -1018,6 +1018,8 @@ config FB_ATMEL
>>>  	select FB_CFB_FILLRECT
>>>  	select FB_CFB_COPYAREA
>>>  	select FB_CFB_IMAGEBLIT
>>> +	select FB_MODE_HELPERS
>>> +	select OF_VIDEOMODE
>>>  	help
>>>  	  This enables support for the AT91/AT32 LCD Controller.
>>>  
>>> diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
>>> index f67e226..4a31570 100644
>>> --- a/drivers/video/atmel_lcdfb.c
>>> +++ b/drivers/video/atmel_lcdfb.c
>>> @@ -20,7 +20,11 @@
>>>  #include <linux/gfp.h>
>>>  #include <linux/module.h>
>>>  #include <linux/platform_data/atmel.h>
>>> +#include <linux/of.h>
>>> +#include <linux/of_device.h>
>>> +#include <linux/of_gpio.h>
>>>  #include <video/of_display_timing.h>
>>
>> As said in patch 1/8, this one belongs to this 4/8 patch.
>>
>>> +#include <video/videomode.h>
>>>  
>>>  #include <mach/cpu.h>
>>>  #include <asm/gpio.h>
>>> @@ -59,6 +63,13 @@ struct atmel_lcdfb_info {
>>>  	struct atmel_lcdfb_config *config;
>>>  };
>>>  
>>> +struct atmel_lcdfb_power_ctrl_gpio {
>>> +	int gpio;
>>> +	int active_low;
>>> +
>>> +	struct list_head list;
>>> +};
>>> +
>>>  #define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
>>>  #define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))
>>>  
>>> @@ -945,16 +956,187 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
>>>  	clk_disable(sinfo->lcdc_clk);
>>>  }
>>>  
>>> +#ifdef CONFIG_OF
>>> +static const struct of_device_id atmel_lcdfb_dt_ids[] = {
>>> +	{ .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
>>> +	{ .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
>>> +	{ .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
>>> +	{ .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
>>> +	{ .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
>>> +	{ .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
>>> +	{ .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
>>> +	{ /* sentinel */ }
>>> +};
>>> +
>>> +MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
>>> +
>>> +static const char *atmel_lcdfb_wiring_modes[] = {
>>> +	[ATMEL_LCDC_WIRING_BGR]	= "BRG",
>>> +	[ATMEL_LCDC_WIRING_RGB]	= "RGB",
>>> +};
>>> +
>>> +const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
>>> +{
>>> +	const char *mode;
>>> +	int err, i;
>>> +
>>> +	err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
>>> +	if (err < 0)
>>> +		return ATMEL_LCDC_WIRING_BGR;
>>> +
>>> +	for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
>>> +		if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
>>> +			return i;
>>> +
>>> +	return -ENODEV;
>>> +}
>>> +
>>> +static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
>>> +{
>>> +	struct atmel_lcdfb_power_ctrl_gpio *og;
>>> +
>>> +	list_for_each_entry(og, &pdata->pwr_gpios, list)
>>> +		gpio_set_value(og->gpio, on);
>>> +}
>>> +
>>> +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
>>> +{
>>> +	struct fb_info *info = sinfo->info;
>>> +	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
>>> +	struct fb_var_screeninfo *var = &info->var;
>>> +	struct device *dev = &sinfo->pdev->dev;
>>> +	struct device_node *np =dev->of_node;
>>> +	struct device_node *display_np;
>>> +	struct device_node *timings_np;
>>> +	struct display_timings *timings;
>>> +	enum of_gpio_flags flags;
>>> +	struct atmel_lcdfb_power_ctrl_gpio *og;
>>> +	bool is_gpio_power = false;
>>> +	int ret = -ENOENT;
>>> +	int i, gpio;
>>> +
>>> +	sinfo->config = (struct atmel_lcdfb_config*)
>>> +		of_match_device(atmel_lcdfb_dt_ids, dev)->data;
>>
>> Please split it in 2 steps, otherwise the day that the drivers doesn't
>> find the device in dt_ids table, it hangs here with an Oops.
> no as you will never end here in this case

Ok, I see.

>>
>>> +
>>> +	display_np = of_parse_phandle(np, "display", 0);
>>> +	if (!display_np) {
>>> +		dev_err(dev, "failed to find display phandle\n");
>>> +		return -ENOENT;
>>> +	}
>>> +
>>> +	ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
>>> +	if (ret < 0) {
>>> +		dev_err(dev, "failed to get property bits-per-pixel\n");
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
>>> +	if (ret < 0) {
>>> +		dev_err(dev, "failed to get property atmel,guard-time\n");
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
>>> +	if (ret < 0) {
>>> +		dev_err(dev, "failed to get property atmel,lcdcon2\n");
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
>>> +	if (ret < 0) {
>>> +		dev_err(dev, "failed to get property bits-per-pixel\n");
>>
>> No, wrong error message.
>>
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	ret = -ENOMEM;
>>> +	for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
>>> +		gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
>>> +					       i, &flags);
>>> +		if (gpio < 0)
>>> +			continue;
>>> +
>>> +		og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
>>> +		if (!og)
>>> +			goto put_display_node;
>>> +
>>> +		og->gpio = gpio;
>>> +		og->active_low = flags & OF_GPIO_ACTIVE_LOW;
>>> +		is_gpio_power = true;
>>> +		ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
>>> +		if (ret) {
>>> +			dev_err(dev, "request gpio %d failed\n", gpio);
>>> +			goto put_display_node;
>>> +		}
>>> +
>>> +		ret = gpio_direction_output(gpio, og->active_low);
>>> +		if (ret) {
>>> +			dev_err(dev, "set direction output gpio %d failed\n", gpio);
>>> +			goto put_display_node;
>>> +		}
>>> +	}
>>> +
>>> +	if (is_gpio_power)
>>> +		pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
>>> +
>>> +	ret = atmel_lcdfb_get_of_wiring_modes(display_np);
>>> +	if (ret < 0) {
>>> +		dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
>>> +		goto put_display_node;
>>> +	}
>>> +	pdata->lcd_wiring_mode = ret;
>>> +
>>> +	pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
>>> +
>>> +	timings = of_get_display_timings(display_np);
>>> +	if (!timings) {
>>> +		dev_err(dev, "failed to get display timings\n");
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	timings_np = of_find_node_by_name(display_np, "display-timings");
>>> +	if (!timings_np) {
>>> +		dev_err(dev, "failed to find display-timings node\n");
>>> +		goto put_display_node;
>>> +	}
>>> +
>>> +	for (i = 0; i < of_get_child_count(timings_np); i++) {
>>> +		struct videomode vm;
>>> +		struct fb_videomode fb_vm;
>>> +
>>> +		ret = videomode_from_timing(timings, &vm, i);
>>> +		if (ret < 0)
>>> +			goto put_timings_node;
>>> +		ret = fb_videomode_from_videomode(&vm, &fb_vm);
>>> +		if (ret < 0)
>>> +			goto put_timings_node;
>>> +
>>> +		fb_add_videomode(&fb_vm, &info->modelist);
>>> +	}
>>> +
>>> +	return 0;
>>> +
>>> +put_timings_node:
>>> +	of_node_put(timings_np);
>>> +put_display_node:
>>> +	of_node_put(display_np);
>>> +	return ret;
>>> +}
>>> +#else
>>> +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
>>> +{
>>> +	return 0;
>>> +}
>>> +#endif
>>>  
>>>  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  {
>>>  	struct device *dev = &pdev->dev;
>>>  	struct fb_info *info;
>>>  	struct atmel_lcdfb_info *sinfo;
>>> -	struct atmel_lcdfb_pdata *pdata;
>>> -	struct fb_videomode fbmode;
>>> +	struct atmel_lcdfb_pdata *pdata = NULL;
>>>  	struct resource *regs = NULL;
>>>  	struct resource *map = NULL;
>>> +	struct fb_modelist *modelist;
>>>  	int ret;
>>>  
>>>  	dev_dbg(dev, "%s BEGIN\n", __func__);
>>> @@ -967,17 +1149,35 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  	}
>>>  
>>>  	sinfo = info->par;
>>> +	sinfo->pdev = pdev;
>>> +	sinfo->info = info;
>>> +
>>> +	INIT_LIST_HEAD(&info->modelist);
>>>  
>>> -	if (dev->platform_data) {
>>> -		pdata = (struct atmel_lcdfb_pdata *)dev->platform_data;
>>> +	if (pdev->dev.of_node) {
>>> +		ret = atmel_lcdfb_of_init(sinfo);
>>> +		if (ret)
>>> +			goto free_info;
>>> +	} else if (dev->platform_data) {
>>> +		struct fb_monspecs *monspecs;
>>> +		int i;
>>> +
>>> +		pdata = dev->platform_data;
>>> +		monspecs = pdata->default_monspecs;
>>>  		sinfo->pdata = *pdata;
>>> +
>>> +		for (i = 0; i < monspecs->modedb_len; i++)
>>> +			fb_add_videomode(&monspecs->modedb[i], &info->modelist);
>>> +
>>> +		sinfo->config = atmel_lcdfb_get_config(pdev);
>>> +
>>> +		info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
>>> +		memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
>>>  	} else {
>>>  		dev_err(dev, "cannot get default configuration\n");
>>>  		goto free_info;
>>>  	}
>>> -	sinfo->info = info;
>>> -	sinfo->pdev = pdev;
>>> -	sinfo->config = atmel_lcdfb_get_config(pdev);
>>> +
>>>  	if (!sinfo->config)
>>>  		goto free_info;
>>>  
>>> @@ -986,7 +1186,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  	info->pseudo_palette = sinfo->pseudo_palette;
>>>  	info->fbops = &atmel_lcdfb_ops;
>>>  
>>> -	memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
>>>  	info->fix = atmel_lcdfb_fix;
>>>  
>>>  	/* Enable LCDC Clocks */
>>> @@ -1002,14 +1201,11 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  	}
>>>  	atmel_lcdfb_start_clock(sinfo);
>>>  
>>> -	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
>>> -			info->monspecs.modedb_len, info->monspecs.modedb,
>>> -			pdata->default_bpp);
>>> -	if (!ret) {
>>> -		dev_err(dev, "no suitable video mode found\n");
>>> -		goto stop_clk;
>>> -	}
>>> +	modelist = list_first_entry(&info->modelist,
>>> +			struct fb_modelist, list);
>>> +	fb_videomode_to_var(&info->var, &modelist->mode);
>>>  
>>> +	atmel_lcdfb_check_var(&info->var, info);
>>>  
>>>  	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>>  	if (!regs) {
>>> @@ -1093,18 +1289,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  		goto unregister_irqs;
>>>  	}
>>>  
>>> -	/*
>>> -	 * This makes sure that our colour bitfield
>>> -	 * descriptors are correctly initialised.
>>> -	 */
>>> -	atmel_lcdfb_check_var(&info->var, info);
>>> -
>>> -	ret = fb_set_var(info, &info->var);
>>> -	if (ret) {
>>> -		dev_warn(dev, "unable to set display parameters\n");
>>> -		goto free_cmap;
>>> -	}
>>> -
>>>  	dev_set_drvdata(dev, info);
>>>  
>>>  	/*
>>> @@ -1116,10 +1300,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  		goto reset_drvdata;
>>>  	}
>>>  
>>> -	/* add selected videomode to modelist */
>>> -	fb_var_to_videomode(&fbmode, &info->var);
>>> -	fb_add_videomode(&fbmode, &info->modelist);
>>> -
>>>  	/* Power up the LCDC screen */
>>>  	atmel_lcdfb_power_control(sinfo, 1);
>>>  
>>> @@ -1130,7 +1310,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>>>  
>>>  reset_drvdata:
>>>  	dev_set_drvdata(dev, NULL);
>>> -free_cmap:
>>>  	fb_dealloc_cmap(&info->cmap);
>>>  unregister_irqs:
>>>  	cancel_work_sync(&sinfo->task);
>>> @@ -1249,6 +1428,7 @@ static struct platform_driver atmel_lcdfb_driver = {
>>>  	.driver		= {
>>>  		.name	= "atmel_lcdfb",
>>>  		.owner	= THIS_MODULE,
>>> +		.of_match_table	= of_match_ptr(atmel_lcdfb_dt_ids),
>>>  	},
>>>  };
>>>  
>>>
>>
>>
>> -- 
>> Nicolas Ferre
> 
>
Richard Genoud May 29, 2013, 3:01 p.m. UTC | #4
2013/4/11 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>:
> get display timings from device tree
> Use videomode helpers to get display timings and configurations from
> device tree
>
> Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
> Cc: linux-fbdev@vger.kernel.org
> Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> ---
>  .../devicetree/bindings/video/atmel,lcdc.txt       |   75 ++++++
>  drivers/video/Kconfig                              |    2 +
>  drivers/video/atmel_lcdfb.c                        |  244 +++++++++++++++++---
>  3 files changed, 289 insertions(+), 32 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt
>
> diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
> new file mode 100644
> index 0000000..1ec175e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
> @@ -0,0 +1,75 @@
> +Atmel LCDC Framebuffer
> +-----------------------------------------------------
> +
> +Required properties:
> +- compatible :
> +       "atmel,at91sam9261-lcdc" ,
> +       "atmel,at91sam9263-lcdc" ,
> +       "atmel,at91sam9g10-lcdc" ,
> +       "atmel,at91sam9g45-lcdc" ,
> +       "atmel,at91sam9g45es-lcdc" ,
> +       "atmel,at91sam9rl-lcdc" ,
> +       "atmel,at32ap-lcdc"
> +- reg : Should contain 1 register ranges(address and length)
> +- interrupts : framebuffer controller interrupt
> +- display: a phandle pointing to the display node
> +
> +Required nodes:
> +- display: a display node is required to initialize the lcd panel
> +       This should be in the board dts.
> +- default-mode: a videomode within the display with timing parameters
> +       as specified below.
> +
> +Example:
> +
> +       fb0: fb@0x00500000 {
> +               compatible = "atmel,at91sam9g45-lcdc";
> +               reg = <0x00500000 0x1000>;
> +               interrupts = <23 3 0>;
> +               pinctrl-names = "default";
> +               pinctrl-0 = <&pinctrl_fb>;
> +               display = <&display0>;
> +               status = "okay";
> +               #address-cells = <1>;
> +               #size-cells = <1>;
> +
> +       };
> +
> +Atmel LCDC Display
> +-----------------------------------------------------
> +Required properties (as per of_videomode_helper):
> +
> + - atmel,dmacon: dma controler configuration
> + - atmel,lcdcon2: lcd controler configuration
> + - atmel,guard-time: lcd guard time (Delay in frame periods)
> + - bits-per-pixel: lcd panel bit-depth.
> +
> +Optional properties (as per of_videomode_helper):
> + - atmel,lcdcon-backlight: enable backlight
> + - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"
> + - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
still on lcdcon_pol_negative, we can add something like that:
 - atmel,lcdcon-pwm-pulse-low: Output PWM pulses are low level (high
level if not set)

> +
> +Example:
> +       display0: display {
> +               bits-per-pixel = <32>;
> +               atmel,lcdcon-backlight;
> +               atmel,dmacon = <0x1>;
> +               atmel,lcdcon2 = <0x80008002>;
> +               atmel,guard-time = <9>;
> +               atmel,lcd-wiring-mode = <1>;
> +
> +               display-timings {
> +                       native-mode = <&timing0>;
> +                       timing0: timing0 {
> +                               clock-frequency = <9000000>;
> +                               hactive = <480>;
> +                               vactive = <272>;
> +                               hback-porch = <1>;
> +                               hfront-porch = <1>;
> +                               vback-porch = <40>;
> +                               vfront-porch = <1>;
> +                               hsync-len = <45>;
> +                               vsync-len = <1>;
> +                       };
> +               };
> +       };
> diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
> index 4c1546f..0687482 100644
> --- a/drivers/video/Kconfig
> +++ b/drivers/video/Kconfig
> @@ -1018,6 +1018,8 @@ config FB_ATMEL
>         select FB_CFB_FILLRECT
>         select FB_CFB_COPYAREA
>         select FB_CFB_IMAGEBLIT
> +       select FB_MODE_HELPERS
> +       select OF_VIDEOMODE
>         help
>           This enables support for the AT91/AT32 LCD Controller.
>
> diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
> index f67e226..4a31570 100644
> --- a/drivers/video/atmel_lcdfb.c
> +++ b/drivers/video/atmel_lcdfb.c
> @@ -20,7 +20,11 @@
>  #include <linux/gfp.h>
>  #include <linux/module.h>
>  #include <linux/platform_data/atmel.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
>  #include <video/of_display_timing.h>
> +#include <video/videomode.h>
>
>  #include <mach/cpu.h>
>  #include <asm/gpio.h>
> @@ -59,6 +63,13 @@ struct atmel_lcdfb_info {
>         struct atmel_lcdfb_config *config;
>  };
>
> +struct atmel_lcdfb_power_ctrl_gpio {
> +       int gpio;
> +       int active_low;
> +
> +       struct list_head list;
> +};
> +
>  #define lcdc_readl(sinfo, reg)         __raw_readl((sinfo)->mmio+(reg))
>  #define lcdc_writel(sinfo, reg, val)   __raw_writel((val), (sinfo)->mmio+(reg))
>
> @@ -945,16 +956,187 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
>         clk_disable(sinfo->lcdc_clk);
>  }
>
> +#ifdef CONFIG_OF
> +static const struct of_device_id atmel_lcdfb_dt_ids[] = {
> +       { .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
> +       { .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
> +       { .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
> +       { .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
> +       { .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
> +       { .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
> +       { .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
> +       { /* sentinel */ }
> +};
> +
> +MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
> +
> +static const char *atmel_lcdfb_wiring_modes[] = {
> +       [ATMEL_LCDC_WIRING_BGR] = "BRG",
> +       [ATMEL_LCDC_WIRING_RGB] = "RGB",
> +};
> +
> +const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
> +{
> +       const char *mode;
> +       int err, i;
> +
> +       err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
> +       if (err < 0)
> +               return ATMEL_LCDC_WIRING_BGR;
> +
> +       for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
> +               if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
> +                       return i;
> +
> +       return -ENODEV;
> +}
> +
> +static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
> +{
> +       struct atmel_lcdfb_power_ctrl_gpio *og;
> +
> +       list_for_each_entry(og, &pdata->pwr_gpios, list)
> +               gpio_set_value(og->gpio, on);
> +}
> +
> +static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
> +{
> +       struct fb_info *info = sinfo->info;
> +       struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
> +       struct fb_var_screeninfo *var = &info->var;
> +       struct device *dev = &sinfo->pdev->dev;
> +       struct device_node *np =dev->of_node;
> +       struct device_node *display_np;
> +       struct device_node *timings_np;
> +       struct display_timings *timings;
> +       enum of_gpio_flags flags;
> +       struct atmel_lcdfb_power_ctrl_gpio *og;
> +       bool is_gpio_power = false;
> +       int ret = -ENOENT;
> +       int i, gpio;
> +
> +       sinfo->config = (struct atmel_lcdfb_config*)
> +               of_match_device(atmel_lcdfb_dt_ids, dev)->data;
> +
> +       display_np = of_parse_phandle(np, "display", 0);
> +       if (!display_np) {
> +               dev_err(dev, "failed to find display phandle\n");
> +               return -ENOENT;
> +       }
> +
> +       ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
> +       if (ret < 0) {
> +               dev_err(dev, "failed to get property bits-per-pixel\n");
> +               goto put_display_node;
> +       }
> +
> +       ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
> +       if (ret < 0) {
> +               dev_err(dev, "failed to get property atmel,guard-time\n");
> +               goto put_display_node;
> +       }
> +
> +       ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
> +       if (ret < 0) {
> +               dev_err(dev, "failed to get property atmel,lcdcon2\n");
> +               goto put_display_node;
> +       }
> +
> +       ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
> +       if (ret < 0) {
> +               dev_err(dev, "failed to get property bits-per-pixel\n");
> +               goto put_display_node;
> +       }
> +
> +       ret = -ENOMEM;
> +       for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
> +               gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
> +                                              i, &flags);
> +               if (gpio < 0)
> +                       continue;
> +
> +               og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
> +               if (!og)
> +                       goto put_display_node;
> +
> +               og->gpio = gpio;
> +               og->active_low = flags & OF_GPIO_ACTIVE_LOW;
> +               is_gpio_power = true;
> +               ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
> +               if (ret) {
> +                       dev_err(dev, "request gpio %d failed\n", gpio);
> +                       goto put_display_node;
> +               }
> +
> +               ret = gpio_direction_output(gpio, og->active_low);
> +               if (ret) {
> +                       dev_err(dev, "set direction output gpio %d failed\n", gpio);
> +                       goto put_display_node;
> +               }
> +       }
> +
> +       if (is_gpio_power)
> +               pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
> +
> +       ret = atmel_lcdfb_get_of_wiring_modes(display_np);
> +       if (ret < 0) {
> +               dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
> +               goto put_display_node;
> +       }
> +       pdata->lcd_wiring_mode = ret;
> +
> +       pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");

and here, something like:
pdata->lcdcon_pol_negative = of_property_read_bool(display_np,
"atmel,lcdcon-pwm-pulse-low");
would be nice


Regards,
Richard.
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
new file mode 100644
index 0000000..1ec175e
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
@@ -0,0 +1,75 @@ 
+Atmel LCDC Framebuffer
+-----------------------------------------------------
+
+Required properties:
+- compatible :
+	"atmel,at91sam9261-lcdc" , 
+	"atmel,at91sam9263-lcdc" ,
+	"atmel,at91sam9g10-lcdc" ,
+	"atmel,at91sam9g45-lcdc" ,
+	"atmel,at91sam9g45es-lcdc" ,
+	"atmel,at91sam9rl-lcdc" ,
+	"atmel,at32ap-lcdc"
+- reg : Should contain 1 register ranges(address and length)
+- interrupts : framebuffer controller interrupt
+- display: a phandle pointing to the display node
+
+Required nodes:
+- display: a display node is required to initialize the lcd panel
+	This should be in the board dts.
+- default-mode: a videomode within the display with timing parameters
+	as specified below.
+
+Example:
+
+	fb0: fb@0x00500000 {
+		compatible = "atmel,at91sam9g45-lcdc";
+		reg = <0x00500000 0x1000>;
+		interrupts = <23 3 0>;
+		pinctrl-names = "default";
+		pinctrl-0 = <&pinctrl_fb>;
+		display = <&display0>;
+		status = "okay";
+		#address-cells = <1>;
+		#size-cells = <1>;
+
+	};
+
+Atmel LCDC Display
+-----------------------------------------------------
+Required properties (as per of_videomode_helper):
+
+ - atmel,dmacon: dma controler configuration
+ - atmel,lcdcon2: lcd controler configuration
+ - atmel,guard-time: lcd guard time (Delay in frame periods)
+ - bits-per-pixel: lcd panel bit-depth.
+
+Optional properties (as per of_videomode_helper):
+ - atmel,lcdcon-backlight: enable backlight
+ - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"
+ - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
+
+Example:
+	display0: display {
+		bits-per-pixel = <32>;
+		atmel,lcdcon-backlight;
+		atmel,dmacon = <0x1>;
+		atmel,lcdcon2 = <0x80008002>;
+		atmel,guard-time = <9>;
+		atmel,lcd-wiring-mode = <1>;
+
+		display-timings {
+			native-mode = <&timing0>;
+			timing0: timing0 {
+				clock-frequency = <9000000>;
+				hactive = <480>;
+				vactive = <272>;
+				hback-porch = <1>;
+				hfront-porch = <1>;
+				vback-porch = <40>;
+				vfront-porch = <1>;
+				hsync-len = <45>;
+				vsync-len = <1>;
+			};
+		};
+	};
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 4c1546f..0687482 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1018,6 +1018,8 @@  config FB_ATMEL
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT
+	select FB_MODE_HELPERS
+	select OF_VIDEOMODE
 	help
 	  This enables support for the AT91/AT32 LCD Controller.
 
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index f67e226..4a31570 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -20,7 +20,11 @@ 
 #include <linux/gfp.h>
 #include <linux/module.h>
 #include <linux/platform_data/atmel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
 #include <video/of_display_timing.h>
+#include <video/videomode.h>
 
 #include <mach/cpu.h>
 #include <asm/gpio.h>
@@ -59,6 +63,13 @@  struct atmel_lcdfb_info {
 	struct atmel_lcdfb_config *config;
 };
 
+struct atmel_lcdfb_power_ctrl_gpio {
+	int gpio;
+	int active_low;
+
+	struct list_head list;
+};
+
 #define lcdc_readl(sinfo, reg)		__raw_readl((sinfo)->mmio+(reg))
 #define lcdc_writel(sinfo, reg, val)	__raw_writel((val), (sinfo)->mmio+(reg))
 
@@ -945,16 +956,187 @@  static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
 	clk_disable(sinfo->lcdc_clk);
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id atmel_lcdfb_dt_ids[] = {
+	{ .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
+	{ .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
+	{ .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
+	{ .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
+	{ .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
+	{ .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
+	{ .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
+	{ /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
+
+static const char *atmel_lcdfb_wiring_modes[] = {
+	[ATMEL_LCDC_WIRING_BGR]	= "BRG",
+	[ATMEL_LCDC_WIRING_RGB]	= "RGB",
+};
+
+const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
+{
+	const char *mode;
+	int err, i;
+
+	err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
+	if (err < 0)
+		return ATMEL_LCDC_WIRING_BGR;
+
+	for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
+		if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
+			return i;
+
+	return -ENODEV;
+}
+
+static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
+{
+	struct atmel_lcdfb_power_ctrl_gpio *og;
+
+	list_for_each_entry(og, &pdata->pwr_gpios, list)
+		gpio_set_value(og->gpio, on);
+}
+
+static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
+{
+	struct fb_info *info = sinfo->info;
+	struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
+	struct fb_var_screeninfo *var = &info->var;
+	struct device *dev = &sinfo->pdev->dev;
+	struct device_node *np =dev->of_node;
+	struct device_node *display_np;
+	struct device_node *timings_np;
+	struct display_timings *timings;
+	enum of_gpio_flags flags;
+	struct atmel_lcdfb_power_ctrl_gpio *og;
+	bool is_gpio_power = false;
+	int ret = -ENOENT;
+	int i, gpio;
+
+	sinfo->config = (struct atmel_lcdfb_config*)
+		of_match_device(atmel_lcdfb_dt_ids, dev)->data;
+
+	display_np = of_parse_phandle(np, "display", 0);
+	if (!display_np) {
+		dev_err(dev, "failed to find display phandle\n");
+		return -ENOENT;
+	}
+
+	ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
+	if (ret < 0) {
+		dev_err(dev, "failed to get property bits-per-pixel\n");
+		goto put_display_node;
+	}
+
+	ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
+	if (ret < 0) {
+		dev_err(dev, "failed to get property atmel,guard-time\n");
+		goto put_display_node;
+	}
+
+	ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
+	if (ret < 0) {
+		dev_err(dev, "failed to get property atmel,lcdcon2\n");
+		goto put_display_node;
+	}
+
+	ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
+	if (ret < 0) {
+		dev_err(dev, "failed to get property bits-per-pixel\n");
+		goto put_display_node;
+	}
+
+	ret = -ENOMEM;
+	for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
+		gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
+					       i, &flags);
+		if (gpio < 0)
+			continue;
+
+		og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
+		if (!og)
+			goto put_display_node;
+
+		og->gpio = gpio;
+		og->active_low = flags & OF_GPIO_ACTIVE_LOW;
+		is_gpio_power = true;
+		ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
+		if (ret) {
+			dev_err(dev, "request gpio %d failed\n", gpio);
+			goto put_display_node;
+		}
+
+		ret = gpio_direction_output(gpio, og->active_low);
+		if (ret) {
+			dev_err(dev, "set direction output gpio %d failed\n", gpio);
+			goto put_display_node;
+		}
+	}
+
+	if (is_gpio_power)
+		pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
+
+	ret = atmel_lcdfb_get_of_wiring_modes(display_np);
+	if (ret < 0) {
+		dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
+		goto put_display_node;
+	}
+	pdata->lcd_wiring_mode = ret;
+
+	pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
+
+	timings = of_get_display_timings(display_np);
+	if (!timings) {
+		dev_err(dev, "failed to get display timings\n");
+		goto put_display_node;
+	}
+
+	timings_np = of_find_node_by_name(display_np, "display-timings");
+	if (!timings_np) {
+		dev_err(dev, "failed to find display-timings node\n");
+		goto put_display_node;
+	}
+
+	for (i = 0; i < of_get_child_count(timings_np); i++) {
+		struct videomode vm;
+		struct fb_videomode fb_vm;
+
+		ret = videomode_from_timing(timings, &vm, i);
+		if (ret < 0)
+			goto put_timings_node;
+		ret = fb_videomode_from_videomode(&vm, &fb_vm);
+		if (ret < 0)
+			goto put_timings_node;
+
+		fb_add_videomode(&fb_vm, &info->modelist);
+	}
+
+	return 0;
+
+put_timings_node:
+	of_node_put(timings_np);
+put_display_node:
+	of_node_put(display_np);
+	return ret;
+}
+#else
+static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
+{
+	return 0;
+}
+#endif
 
 static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct fb_info *info;
 	struct atmel_lcdfb_info *sinfo;
-	struct atmel_lcdfb_pdata *pdata;
-	struct fb_videomode fbmode;
+	struct atmel_lcdfb_pdata *pdata = NULL;
 	struct resource *regs = NULL;
 	struct resource *map = NULL;
+	struct fb_modelist *modelist;
 	int ret;
 
 	dev_dbg(dev, "%s BEGIN\n", __func__);
@@ -967,17 +1149,35 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 	}
 
 	sinfo = info->par;
+	sinfo->pdev = pdev;
+	sinfo->info = info;
+
+	INIT_LIST_HEAD(&info->modelist);
 
-	if (dev->platform_data) {
-		pdata = (struct atmel_lcdfb_pdata *)dev->platform_data;
+	if (pdev->dev.of_node) {
+		ret = atmel_lcdfb_of_init(sinfo);
+		if (ret)
+			goto free_info;
+	} else if (dev->platform_data) {
+		struct fb_monspecs *monspecs;
+		int i;
+
+		pdata = dev->platform_data;
+		monspecs = pdata->default_monspecs;
 		sinfo->pdata = *pdata;
+
+		for (i = 0; i < monspecs->modedb_len; i++)
+			fb_add_videomode(&monspecs->modedb[i], &info->modelist);
+
+		sinfo->config = atmel_lcdfb_get_config(pdev);
+
+		info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
+		memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
 	} else {
 		dev_err(dev, "cannot get default configuration\n");
 		goto free_info;
 	}
-	sinfo->info = info;
-	sinfo->pdev = pdev;
-	sinfo->config = atmel_lcdfb_get_config(pdev);
+
 	if (!sinfo->config)
 		goto free_info;
 
@@ -986,7 +1186,6 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 	info->pseudo_palette = sinfo->pseudo_palette;
 	info->fbops = &atmel_lcdfb_ops;
 
-	memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
 	info->fix = atmel_lcdfb_fix;
 
 	/* Enable LCDC Clocks */
@@ -1002,14 +1201,11 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 	}
 	atmel_lcdfb_start_clock(sinfo);
 
-	ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
-			info->monspecs.modedb_len, info->monspecs.modedb,
-			pdata->default_bpp);
-	if (!ret) {
-		dev_err(dev, "no suitable video mode found\n");
-		goto stop_clk;
-	}
+	modelist = list_first_entry(&info->modelist,
+			struct fb_modelist, list);
+	fb_videomode_to_var(&info->var, &modelist->mode);
 
+	atmel_lcdfb_check_var(&info->var, info);
 
 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!regs) {
@@ -1093,18 +1289,6 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 		goto unregister_irqs;
 	}
 
-	/*
-	 * This makes sure that our colour bitfield
-	 * descriptors are correctly initialised.
-	 */
-	atmel_lcdfb_check_var(&info->var, info);
-
-	ret = fb_set_var(info, &info->var);
-	if (ret) {
-		dev_warn(dev, "unable to set display parameters\n");
-		goto free_cmap;
-	}
-
 	dev_set_drvdata(dev, info);
 
 	/*
@@ -1116,10 +1300,6 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 		goto reset_drvdata;
 	}
 
-	/* add selected videomode to modelist */
-	fb_var_to_videomode(&fbmode, &info->var);
-	fb_add_videomode(&fbmode, &info->modelist);
-
 	/* Power up the LCDC screen */
 	atmel_lcdfb_power_control(sinfo, 1);
 
@@ -1130,7 +1310,6 @@  static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 
 reset_drvdata:
 	dev_set_drvdata(dev, NULL);
-free_cmap:
 	fb_dealloc_cmap(&info->cmap);
 unregister_irqs:
 	cancel_work_sync(&sinfo->task);
@@ -1249,6 +1428,7 @@  static struct platform_driver atmel_lcdfb_driver = {
 	.driver		= {
 		.name	= "atmel_lcdfb",
 		.owner	= THIS_MODULE,
+		.of_match_table	= of_match_ptr(atmel_lcdfb_dt_ids),
 	},
 };