diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/video/atmel_lcdfb.c | 115 | ||||
| -rw-r--r-- | drivers/video/backlight/Kconfig | 13 |
2 files changed, 124 insertions, 4 deletions
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c index 5d22ea532e42..fc65c02306dd 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 9609a6c676be..924e2551044a 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 |