fbdev: sh_mobile_lcdcfb: add backlight support
Alexandre Courbot [Wed, 16 Feb 2011 03:49:01 +0000 (03:49 +0000)]
Support for backlight devices controlled through board-specific
routines. Backlights can be defined per-channel and follow fbdev
directives to switch off as the LCD blanks or is turned on/off.

Signed-off-by: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

drivers/video/Kconfig
drivers/video/sh_mobile_lcdcfb.c
drivers/video/sh_mobile_lcdcfb.h
include/video/sh_mobile_lcdc.h

index 6bafb51..a222d65 100644 (file)
@@ -2005,6 +2005,7 @@ config FB_SH_MOBILE_LCDC
        select FB_SYS_IMAGEBLIT
        select FB_SYS_FOPS
        select FB_DEFERRED_IO
+       select FB_BACKLIGHT
        select SH_MIPI_DSI if SH_LCD_MIPI_DSI
        ---help---
          Frame buffer driver for the on-chip SH-Mobile LCD controller.
index bf12e53..e040e46 100644 (file)
@@ -21,6 +21,8 @@
 #include <linux/ioctl.h>
 #include <linux/slab.h>
 #include <linux/console.h>
+#include <linux/backlight.h>
+#include <linux/gpio.h>
 #include <video/sh_mobile_lcdc.h>
 #include <asm/atomic.h>
 
@@ -618,6 +620,11 @@ static int sh_mobile_lcdc_start(struct sh_mobile_lcdc_priv *priv)
                        board_cfg->display_on(board_cfg->board_data, ch->info);
                        module_put(board_cfg->owner);
                }
+
+               if (ch->bl) {
+                       ch->bl->props.power = FB_BLANK_UNBLANK;
+                       backlight_update_status(ch->bl);
+               }
        }
 
        return 0;
@@ -648,6 +655,11 @@ static void sh_mobile_lcdc_stop(struct sh_mobile_lcdc_priv *priv)
                        sh_mobile_lcdc_clk_on(priv);
                }
 
+               if (ch->bl) {
+                       ch->bl->props.power = FB_BLANK_POWERDOWN;
+                       backlight_update_status(ch->bl);
+               }
+
                board_cfg = &ch->cfg.board_cfg;
                if (try_module_get(board_cfg->owner) && board_cfg->display_off) {
                        board_cfg->display_off(board_cfg->board_data);
@@ -980,6 +992,64 @@ static struct fb_ops sh_mobile_lcdc_ops = {
        .fb_check_var   = sh_mobile_check_var,
 };
 
+static int sh_mobile_lcdc_update_bl(struct backlight_device *bdev)
+{
+       struct sh_mobile_lcdc_chan *ch = bl_get_data(bdev);
+       struct sh_mobile_lcdc_board_cfg *cfg = &ch->cfg.board_cfg;
+       int brightness = bdev->props.brightness;
+
+       if (bdev->props.power != FB_BLANK_UNBLANK ||
+           bdev->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
+               brightness = 0;
+
+       return cfg->set_brightness(cfg->board_data, brightness);
+}
+
+static int sh_mobile_lcdc_get_brightness(struct backlight_device *bdev)
+{
+       struct sh_mobile_lcdc_chan *ch = bl_get_data(bdev);
+       struct sh_mobile_lcdc_board_cfg *cfg = &ch->cfg.board_cfg;
+
+       return cfg->get_brightness(cfg->board_data);
+}
+
+static int sh_mobile_lcdc_check_fb(struct backlight_device *bdev,
+                                  struct fb_info *info)
+{
+       return (info->bl_dev == bdev);
+}
+
+static struct backlight_ops sh_mobile_lcdc_bl_ops = {
+       .options        = BL_CORE_SUSPENDRESUME,
+       .update_status  = sh_mobile_lcdc_update_bl,
+       .get_brightness = sh_mobile_lcdc_get_brightness,
+       .check_fb       = sh_mobile_lcdc_check_fb,
+};
+
+static struct backlight_device *sh_mobile_lcdc_bl_probe(struct device *parent,
+                                              struct sh_mobile_lcdc_chan *ch)
+{
+       struct backlight_device *bl;
+
+       bl = backlight_device_register(ch->cfg.bl_info.name, parent, ch,
+                                      &sh_mobile_lcdc_bl_ops, NULL);
+       if (!bl) {
+               dev_err(parent, "unable to register backlight device\n");
+               return NULL;
+       }
+
+       bl->props.max_brightness = ch->cfg.bl_info.max_brightness;
+       bl->props.brightness = bl->props.max_brightness;
+       backlight_update_status(bl);
+
+       return bl;
+}
+
+static void sh_mobile_lcdc_bl_remove(struct backlight_device *bdev)
+{
+       backlight_device_unregister(bdev);
+}
+
 static int sh_mobile_lcdc_set_bpp(struct fb_var_screeninfo *var, int bpp)
 {
        switch (bpp) {
@@ -1198,6 +1268,10 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                init_completion(&ch->vsync_completion);
                ch->pan_offset = 0;
 
+               /* probe the backlight is there is one defined */
+               if (ch->cfg.bl_info.max_brightness)
+                       ch->bl = sh_mobile_lcdc_bl_probe(&pdev->dev, ch);
+
                switch (pdata->ch[i].chan) {
                case LCDC_CHAN_MAINLCD:
                        ch->enabled = 1 << 1;
@@ -1345,6 +1419,8 @@ static int __devinit sh_mobile_lcdc_probe(struct platform_device *pdev)
                        }
                }
 
+               info->bl_dev = ch->bl;
+
                error = register_framebuffer(info);
                if (error < 0)
                        goto err1;
@@ -1404,6 +1480,11 @@ static int sh_mobile_lcdc_remove(struct platform_device *pdev)
                framebuffer_release(info);
        }
 
+       for (i = 0; i < ARRAY_SIZE(priv->ch); i++) {
+               if (priv->ch[i].bl)
+                       sh_mobile_lcdc_bl_remove(priv->ch[i].bl);
+       }
+
        if (priv->dot_clk)
                clk_put(priv->dot_clk);
 
index 9ecee2f..03a22dc 100644 (file)
@@ -16,6 +16,7 @@ enum { LDDCKPAT1R, LDDCKPAT2R, LDMT1R, LDMT2R, LDMT3R, LDDFR, LDSM1R,
 
 struct sh_mobile_lcdc_priv;
 struct fb_info;
+struct backlight_device;
 
 struct sh_mobile_lcdc_chan {
        struct sh_mobile_lcdc_priv *lcdc;
@@ -26,6 +27,7 @@ struct sh_mobile_lcdc_chan {
        u32 pseudo_palette[PALETTE_NR];
        unsigned long saved_ch_regs[NR_CH_REGS];
        struct fb_info *info;
+       struct backlight_device *bl;
        dma_addr_t dma_handle;
        struct fb_deferred_io defio;
        struct scatterlist *sglist;
index daabae5..f2e6ab8 100644 (file)
@@ -59,6 +59,8 @@ struct sh_mobile_lcdc_board_cfg {
                               struct sh_mobile_lcdc_sys_bus_ops *sys_ops);
        void (*display_on)(void *board_data, struct fb_info *info);
        void (*display_off)(void *board_data);
+       int (*set_brightness)(void *board_data, int brightness);
+       int (*get_brightness)(void *board_data);
 };
 
 struct sh_mobile_lcdc_lcd_size_cfg { /* width and height of panel in mm */
@@ -66,6 +68,12 @@ struct sh_mobile_lcdc_lcd_size_cfg { /* width and height of panel in mm */
        unsigned long height;
 };
 
+/* backlight info */
+struct sh_mobile_lcdc_bl_info {
+       const char *name;
+       int max_brightness;
+};
+
 struct sh_mobile_lcdc_chan_cfg {
        int chan;
        int bpp;
@@ -76,6 +84,7 @@ struct sh_mobile_lcdc_chan_cfg {
        int num_cfg;
        struct sh_mobile_lcdc_lcd_size_cfg lcd_size_cfg;
        struct sh_mobile_lcdc_board_cfg board_cfg;
+       struct sh_mobile_lcdc_bl_info bl_info;
        struct sh_mobile_lcdc_sys_bus_cfg sys_bus_cfg; /* only for SYSn I/F */
 };