aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--arch/arm/mach-at91/board-sam9261ek.c1
-rw-r--r--arch/arm/mach-at91/board-sam9263ek.c1
-rw-r--r--drivers/video/atmel_lcdfb.c115
-rw-r--r--drivers/video/backlight/Kconfig13
-rw-r--r--include/video/atmel_lcdc.h11
5 files changed, 135 insertions, 6 deletions
diff --git a/arch/arm/mach-at91/board-sam9261ek.c b/arch/arm/mach-at91/board-sam9261ek.c
index aa29ea58ca0..0ce38dfa6eb 100644
--- a/arch/arm/mach-at91/board-sam9261ek.c
+++ b/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,
diff --git a/arch/arm/mach-at91/board-sam9263ek.c b/arch/arm/mach-at91/board-sam9263ek.c
index f09347a86e7..38313abef65 100644
--- a/arch/arm/mach-at91/board-sam9263ek.c
+++ b/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,
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 5d22ea532e4..fc65c02306d 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/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 @@ free_cmap:
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,
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 9609a6c676b..924e2551044 100644
--- a/drivers/video/backlight/Kconfig
+++ b/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
diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h
index 76095e70935..336c20db87f 100644
--- a/include/video/atmel_lcdc.h
+++ b/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);