---

yaml
---
r: 83570
b: refs/heads/master
c: a9a84c3
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b1230ee50a9903a987feaad767fb71e2fd173894
+refs/heads/master: a9a84c37d1ee50db8f3752b117caf2b48dcd4f8a

trunk/arch/arm/mach-at91/board-sam9261ek.c

@@ -383,6 +383,7 @@ static void at91_lcdc_tft_power_control(int on)
 }
 
 static struct atmel_lcdfb_info __initdata ek_lcdc_data = {
+	.lcdcon_is_backlight		= true,
 	.default_bpp			= 16,
 	.default_dmacon			= ATMEL_LCDC_DMAEN,
 	.default_lcdcon2		= AT91SAM9261_DEFAULT_TFT_LCDCON2,

trunk/arch/arm/mach-at91/board-sam9263ek.c

@@ -253,6 +253,7 @@ static void at91_lcdc_power_control(int on)
 
 /* Driver datas */
 static struct atmel_lcdfb_info __initdata ek_lcdc_data = {
+	.lcdcon_is_backlight		= true,
 	.default_bpp			= 16,
 	.default_dmacon			= ATMEL_LCDC_DMAEN,
 	.default_lcdcon2		= AT91SAM9263_DEFAULT_LCDCON2,

trunk/drivers/video/atmel_lcdfb.c

@@ -16,6 +16,7 @@
 #include <linux/fb.h>
 #include <linux/init.h>
 #include <linux/delay.h>
+#include <linux/backlight.h>
 
 #include <asm/arch/board.h>
 #include <asm/arch/cpu.h>
@@ -69,6 +70,107 @@ static void atmel_lcdfb_update_dma2d(struct atmel_lcdfb_info *sinfo,
 }
 #endif
 
+static const u32 contrast_ctr = ATMEL_LCDC_PS_DIV8
+		| ATMEL_LCDC_POL_POSITIVE
+		| ATMEL_LCDC_ENA_PWMENABLE;
+
+#ifdef CONFIG_BACKLIGHT_ATMEL_LCDC
+
+/* some bl->props field just changed */
+static int atmel_bl_update_status(struct backlight_device *bl)
+{
+	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
+	int			power = sinfo->bl_power;
+	int			brightness = bl->props.brightness;
+
+	/* REVISIT there may be a meaningful difference between
+	 * fb_blank and power ... there seem to be some cases
+	 * this doesn't handle correctly.
+	 */
+	if (bl->props.fb_blank != sinfo->bl_power)
+		power = bl->props.fb_blank;
+	else if (bl->props.power != sinfo->bl_power)
+		power = bl->props.power;
+
+	if (brightness < 0 && power == FB_BLANK_UNBLANK)
+		brightness = lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
+	else if (power != FB_BLANK_UNBLANK)
+		brightness = 0;
+
+	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, brightness);
+	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR,
+			brightness ? contrast_ctr : 0);
+
+	bl->props.fb_blank = bl->props.power = sinfo->bl_power = power;
+
+	return 0;
+}
+
+static int atmel_bl_get_brightness(struct backlight_device *bl)
+{
+	struct atmel_lcdfb_info *sinfo = bl_get_data(bl);
+
+	return lcdc_readl(sinfo, ATMEL_LCDC_CONTRAST_VAL);
+}
+
+static struct backlight_ops atmel_lcdc_bl_ops = {
+	.update_status = atmel_bl_update_status,
+	.get_brightness = atmel_bl_get_brightness,
+};
+
+static void init_backlight(struct atmel_lcdfb_info *sinfo)
+{
+	struct backlight_device	*bl;
+
+	sinfo->bl_power = FB_BLANK_UNBLANK;
+
+	if (sinfo->backlight)
+		return;
+
+	bl = backlight_device_register("backlight", &sinfo->pdev->dev,
+			sinfo, &atmel_lcdc_bl_ops);
+	if (IS_ERR(sinfo->backlight)) {
+		dev_err(&sinfo->pdev->dev, "error %ld on backlight register\n",
+				PTR_ERR(bl));
+		return;
+	}
+	sinfo->backlight = bl;
+
+	bl->props.power = FB_BLANK_UNBLANK;
+	bl->props.fb_blank = FB_BLANK_UNBLANK;
+	bl->props.max_brightness = 0xff;
+	bl->props.brightness = atmel_bl_get_brightness(bl);
+}
+
+static void exit_backlight(struct atmel_lcdfb_info *sinfo)
+{
+	if (sinfo->backlight)
+		backlight_device_unregister(sinfo->backlight);
+}
+
+#else
+
+static void init_backlight(struct atmel_lcdfb_info *sinfo)
+{
+	dev_warn(&sinfo->pdev->dev, "backlight control is not available\n");
+}
+
+static void exit_backlight(struct atmel_lcdfb_info *sinfo)
+{
+}
+
+#endif
+
+static void init_contrast(struct atmel_lcdfb_info *sinfo)
+{
+	/* have some default contrast/backlight settings */
+	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, contrast_ctr);
+	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);
+
+	if (sinfo->lcdcon_is_backlight)
+		init_backlight(sinfo);
+}
+
 
 static struct fb_fix_screeninfo atmel_lcdfb_fix __initdata = {
 	.type		= FB_TYPE_PACKED_PIXELS,
@@ -390,10 +492,6 @@ static int atmel_lcdfb_set_par(struct fb_info *info)
 	/* Disable all interrupts */
 	lcdc_writel(sinfo, ATMEL_LCDC_IDR, ~0UL);
 
-	/* Set contrast */
-	value = ATMEL_LCDC_PS_DIV8 | ATMEL_LCDC_POL_POSITIVE | ATMEL_LCDC_ENA_PWMENABLE;
-	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_CTR, value);
-	lcdc_writel(sinfo, ATMEL_LCDC_CONTRAST_VAL, ATMEL_LCDC_CVAL_DEFAULT);
 	/* ...wait for DMA engine to become idle... */
 	while (lcdc_readl(sinfo, ATMEL_LCDC_DMACON) & ATMEL_LCDC_DMABUSY)
 		msleep(10);
@@ -597,6 +695,7 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 		sinfo->default_monspecs = pdata_sinfo->default_monspecs;
 		sinfo->atmel_lcdfb_power_control = pdata_sinfo->atmel_lcdfb_power_control;
 		sinfo->guard_time = pdata_sinfo->guard_time;
+		sinfo->lcdcon_is_backlight = pdata_sinfo->lcdcon_is_backlight;
 	} else {
 		dev_err(dev, "cannot get default configuration\n");
 		goto free_info;
@@ -690,6 +789,9 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 		goto release_mem;
 	}
 
+	/* Initialize PWM for contrast or backlight ("off") */
+	init_contrast(sinfo);
+
 	/* interrupt */
 	ret = request_irq(sinfo->irq_base, atmel_lcdfb_interrupt, 0, pdev->name, info);
 	if (ret) {
@@ -741,6 +843,7 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
 unregister_irqs:
 	free_irq(sinfo->irq_base, info);
 unmap_mmio:
+	exit_backlight(sinfo);
 	iounmap(sinfo->mmio);
 release_mem:
  	release_mem_region(info->fix.mmio_start, info->fix.mmio_len);
@@ -775,6 +878,7 @@ static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
 	if (!sinfo)
 		return 0;
 
+	exit_backlight(sinfo);
 	if (sinfo->atmel_lcdfb_power_control)
 		sinfo->atmel_lcdfb_power_control(0);
 	unregister_framebuffer(info);
@@ -801,6 +905,9 @@ static int __exit atmel_lcdfb_remove(struct platform_device *pdev)
 
 static struct platform_driver atmel_lcdfb_driver = {
 	.remove		= __exit_p(atmel_lcdfb_remove),
+
+// FIXME need suspend, resume
+
 	.driver		= {
 		.name	= "atmel_lcdfb",
 		.owner	= THIS_MODULE,

trunk/drivers/video/backlight/Kconfig

@@ -50,6 +50,19 @@ config BACKLIGHT_CLASS_DEVICE
 	  To have support for your specific LCD panel you will have to
 	  select the proper drivers which depend on this option.
 
+config BACKLIGHT_ATMEL_LCDC
+	bool "Atmel LCDC Contrast-as-Backlight control"
+	depends on BACKLIGHT_CLASS_DEVICE && FB_ATMEL
+	default y if MACH_SAM9261EK || MACH_SAM9263EK
+	help
+	  This provides a backlight control internal to the Atmel LCDC
+	  driver.  If the LCD "contrast control" on your board is wired
+	  so it controls the backlight brightness, select this option to
+	  export this as a PWM-based backlight control.
+
+	  If in doubt, it's safe to enable this option; it doesn't kick
+	  in unless the board's description says it's wired that way.
+
 config BACKLIGHT_CORGI
 	tristate "Generic (aka Sharp Corgi) Backlight Driver"
 	depends on BACKLIGHT_CLASS_DEVICE

trunk/include/video/atmel_lcdc.h

@@ -22,7 +22,7 @@
 #ifndef __ATMEL_LCDC_H__
 #define __ATMEL_LCDC_H__
 
- /* LCD Controller info data structure */
+ /* LCD Controller info data structure, stored in device platform_data */
 struct atmel_lcdfb_info {
 	spinlock_t		lock;
 	struct fb_info		*info;
@@ -33,7 +33,14 @@ struct atmel_lcdfb_info {
 	struct platform_device	*pdev;
 	struct clk		*bus_clk;
 	struct clk		*lcdc_clk;
-	unsigned int		default_bpp;
+
+#ifdef CONFIG_BACKLIGHT_ATMEL_LCDC
+	struct backlight_device	*backlight;
+	u8			bl_power;
+#endif
+	bool			lcdcon_is_backlight;
+
+	u8			default_bpp;
 	unsigned int		default_lcdcon2;
 	unsigned int		default_dmacon;
 	void (*atmel_lcdfb_power_control)(int on);