[PATCH] Rewritten backlight infrastructure for portable Apple computers

This patch contains a total rewrite of the backlight infrastructure for
portable Apple computers.  Backward compatibility is retained.  A sysfs
interface allows userland to control the brightness with more steps than
before.  Userland is allowed to upload a brightness curve for different
monitors, similar to Mac OS X.

[akpm@osdl.org: add needed exports]
Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 225 insertions, 97 deletions

diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index f7bbff4ddc6a..db878fd55fb2 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -64,6 +64,7 @@
 #include <linux/pci.h>
 #include <linux/ioport.h>
 #include <linux/console.h>
+#include <linux/backlight.h>
 #include <asm/io.h>
 
 #ifdef CONFIG_PPC_PMAC
@@ -480,16 +481,6 @@ static struct fb_ops aty128fb_ops = {
         .fb_imageblit   = cfb_imageblit,
 };
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int aty128_set_backlight_enable(int on, int level, void* data);
-static int aty128_set_backlight_level(int level, void* data);
-
-static struct backlight_controller aty128_backlight_controller = {
-        aty128_set_backlight_enable,
-        aty128_set_backlight_level
-};
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
     /*
      * Functions to read from/write to the mmio registers
      *  - endian conversions may possibly be avoided by
@@ -1258,19 +1249,35 @@ static void aty128_set_crt_enable(struct aty128fb_par *par, int on)
 static void aty128_set_lcd_enable(struct aty128fb_par *par, int on)
 {
         u32 reg;
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+        struct fb_info *info = pci_get_drvdata(par->pdev);
+#endif
 
         if (on) {
                 reg = aty_ld_le32(LVDS_GEN_CNTL);
                 reg |= LVDS_ON | LVDS_EN | LVDS_BLON | LVDS_DIGION;
                 reg &= ~LVDS_DISPLAY_DIS;
                 aty_st_le32(LVDS_GEN_CNTL, reg);
-#ifdef CONFIG_PMAC_BACKLIGHT
-                aty128_set_backlight_enable(get_backlight_enable(),
-                                            get_backlight_level(), par);
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+                mutex_lock(&info->bl_mutex);
+                if (info->bl_dev) {
+                        down(&info->bl_dev->sem);
+                        info->bl_dev->props->update_status(info->bl_dev);
+                        up(&info->bl_dev->sem);
+                }
+                mutex_unlock(&info->bl_mutex);
 #endif  
         } else {
-#ifdef CONFIG_PMAC_BACKLIGHT
-                aty128_set_backlight_enable(0, 0, par);
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+                mutex_lock(&info->bl_mutex);
+                if (info->bl_dev) {
+                        down(&info->bl_dev->sem);
+                        info->bl_dev->props->brightness = 0;
+                        info->bl_dev->props->power = FB_BLANK_POWERDOWN;
+                        info->bl_dev->props->update_status(info->bl_dev);
+                        up(&info->bl_dev->sem);
+                }
+                mutex_unlock(&info->bl_mutex);
 #endif  
                 reg = aty_ld_le32(LVDS_GEN_CNTL);
                 reg |= LVDS_DISPLAY_DIS;
@@ -1691,6 +1698,184 @@ static int __init aty128fb_setup(char *options)
 }
 #endif  /*  MODULE  */
 
+/* Backlight */
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+#define MAX_LEVEL 0xFF
+
+static struct backlight_properties aty128_bl_data;
+
+static int aty128_bl_get_level_brightness(struct aty128fb_par *par,
+                int level)
+{
+        struct fb_info *info = pci_get_drvdata(par->pdev);
+        int atylevel;
+
+        /* Get and convert the value */
+        mutex_lock(&info->bl_mutex);
+        atylevel = MAX_LEVEL -
+                (info->bl_curve[level] * FB_BACKLIGHT_MAX / MAX_LEVEL);
+        mutex_unlock(&info->bl_mutex);
+
+        if (atylevel < 0)
+                atylevel = 0;
+        else if (atylevel > MAX_LEVEL)
+                atylevel = MAX_LEVEL;
+
+        return atylevel;
+}
+
+/* We turn off the LCD completely instead of just dimming the backlight.
+ * This provides greater power saving and the display is useless without
+ * backlight anyway
+ */
+#define BACKLIGHT_LVDS_OFF
+/* That one prevents proper CRT output with LCD off */
+#undef BACKLIGHT_DAC_OFF
+
+static int aty128_bl_update_status(struct backlight_device *bd)
+{
+        struct aty128fb_par *par = class_get_devdata(&bd->class_dev);
+        unsigned int reg = aty_ld_le32(LVDS_GEN_CNTL);
+        int level;
+
+        if (bd->props->power != FB_BLANK_UNBLANK ||
+            bd->props->fb_blank != FB_BLANK_UNBLANK ||
+            !par->lcd_on)
+                level = 0;
+        else
+                level = bd->props->brightness;
+
+        reg |= LVDS_BL_MOD_EN | LVDS_BLON;
+        if (level > 0) {
+                reg |= LVDS_DIGION;
+                if (!(reg & LVDS_ON)) {
+                        reg &= ~LVDS_BLON;
+                        aty_st_le32(LVDS_GEN_CNTL, reg);
+                        aty_ld_le32(LVDS_GEN_CNTL);
+                        mdelay(10);
+                        reg |= LVDS_BLON;
+                        aty_st_le32(LVDS_GEN_CNTL, reg);
+                }
+                reg &= ~LVDS_BL_MOD_LEVEL_MASK;
+                reg |= (aty128_bl_get_level_brightness(par, level) << LVDS_BL_MOD_LEVEL_SHIFT);
+#ifdef BACKLIGHT_LVDS_OFF
+                reg |= LVDS_ON | LVDS_EN;
+                reg &= ~LVDS_DISPLAY_DIS;
+#endif
+                aty_st_le32(LVDS_GEN_CNTL, reg);
+#ifdef BACKLIGHT_DAC_OFF
+                aty_st_le32(DAC_CNTL, aty_ld_le32(DAC_CNTL) & (~DAC_PDWN));
+#endif
+        } else {
+                reg &= ~LVDS_BL_MOD_LEVEL_MASK;
+                reg |= (aty128_bl_get_level_brightness(par, 0) << LVDS_BL_MOD_LEVEL_SHIFT);
+#ifdef BACKLIGHT_LVDS_OFF
+                reg |= LVDS_DISPLAY_DIS;
+                aty_st_le32(LVDS_GEN_CNTL, reg);
+                aty_ld_le32(LVDS_GEN_CNTL);
+                udelay(10);
+                reg &= ~(LVDS_ON | LVDS_EN | LVDS_BLON | LVDS_DIGION);
+#endif
+                aty_st_le32(LVDS_GEN_CNTL, reg);
+#ifdef BACKLIGHT_DAC_OFF
+                aty_st_le32(DAC_CNTL, aty_ld_le32(DAC_CNTL) | DAC_PDWN);
+#endif
+        }
+
+        return 0;
+}
+
+static int aty128_bl_get_brightness(struct backlight_device *bd)
+{
+        return bd->props->brightness;
+}
+
+static struct backlight_properties aty128_bl_data = {
+        .owner          = THIS_MODULE,
+        .get_brightness = aty128_bl_get_brightness,
+        .update_status  = aty128_bl_update_status,
+        .max_brightness = (FB_BACKLIGHT_LEVELS - 1),
+};
+
+static void aty128_bl_init(struct aty128fb_par *par)
+{
+        struct fb_info *info = pci_get_drvdata(par->pdev);
+        struct backlight_device *bd;
+        char name[12];
+
+        /* Could be extended to Rage128Pro LVDS output too */
+        if (par->chip_gen != rage_M3)
+                return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+        if (!pmac_has_backlight_type("ati"))
+                return;
+#endif
+
+        snprintf(name, sizeof(name), "aty128bl%d", info->node);
+
+        bd = backlight_device_register(name, par, &aty128_bl_data);
+        if (IS_ERR(bd)) {
+                info->bl_dev = NULL;
+                printk("aty128: Backlight registration failed\n");
+                goto error;
+        }
+
+        mutex_lock(&info->bl_mutex);
+        info->bl_dev = bd;
+        fb_bl_default_curve(info, 0,
+                 63 * FB_BACKLIGHT_MAX / MAX_LEVEL,
+                219 * FB_BACKLIGHT_MAX / MAX_LEVEL);
+        mutex_unlock(&info->bl_mutex);
+
+        up(&bd->sem);
+        bd->props->brightness = aty128_bl_data.max_brightness;
+        bd->props->power = FB_BLANK_UNBLANK;
+        bd->props->update_status(bd);
+        down(&bd->sem);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+        mutex_lock(&pmac_backlight_mutex);
+        if (!pmac_backlight)
+                pmac_backlight = bd;
+        mutex_unlock(&pmac_backlight_mutex);
+#endif
+
+        printk("aty128: Backlight initialized (%s)\n", name);
+
+        return;
+
+error:
+        return;
+}
+
+static void aty128_bl_exit(struct aty128fb_par *par)
+{
+        struct fb_info *info = pci_get_drvdata(par->pdev);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+        mutex_lock(&pmac_backlight_mutex);
+#endif
+
+        mutex_lock(&info->bl_mutex);
+        if (info->bl_dev) {
+#ifdef CONFIG_PMAC_BACKLIGHT
+                if (pmac_backlight == info->bl_dev)
+                        pmac_backlight = NULL;
+#endif
+
+                backlight_device_unregister(info->bl_dev);
+                info->bl_dev = NULL;
+
+                printk("aty128: Backlight unloaded\n");
+        }
+        mutex_unlock(&info->bl_mutex);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+        mutex_unlock(&pmac_backlight_mutex);
+#endif
+}
+#endif /* CONFIG_FB_ATY128_BACKLIGHT */
 
 /*
  *  Initialisation
@@ -1835,17 +2020,15 @@ static int __init aty128_init(struct pci_dev *pdev, const struct pci_device_id *
         if (register_framebuffer(info) < 0)
                 return 0;
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-        /* Could be extended to Rage128Pro LVDS output too */
-        if (par->chip_gen == rage_M3)
-                register_backlight_controller(&aty128_backlight_controller, par, "ati");
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
         par->pm_reg = pci_find_capability(pdev, PCI_CAP_ID_PM);
         par->pdev = pdev;
         par->asleep = 0;
         par->lock_blank = 0;
-        
+
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+        aty128_bl_init(par);
+#endif
+
         printk(KERN_INFO "fb%d: %s frame buffer device on %s\n",
                info->node, info->fix.id, video_card);
 
@@ -1981,6 +2164,10 @@ static void __devexit aty128_remove(struct pci_dev *pdev)
 
         par = info->par;
 
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+        aty128_bl_exit(par);
+#endif
+
         unregister_framebuffer(info);
 #ifdef CONFIG_MTRR
         if (par->mtrr.vram_valid)
@@ -2011,10 +2198,14 @@ static int aty128fb_blank(int blank, struct fb_info *fb)
         if (par->lock_blank || par->asleep)
                 return 0;
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-        if (machine_is(powermac) && blank)
-                set_backlight_enable(0);
-#endif /* CONFIG_PMAC_BACKLIGHT */
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+        if (machine_is(powermac) && blank) {
+                down(&fb->bl_dev->sem);
+                fb->bl_dev->props->power = FB_BLANK_POWERDOWN;
+                fb->bl_dev->props->update_status(fb->bl_dev);
+                up(&fb->bl_dev->sem);
+        }
+#endif
 
         if (blank & FB_BLANK_VSYNC_SUSPEND)
                 state |= 2;
@@ -2029,10 +2220,14 @@ static int aty128fb_blank(int blank, struct fb_info *fb)
                 aty128_set_crt_enable(par, par->crt_on && !blank);
                 aty128_set_lcd_enable(par, par->lcd_on && !blank);
         }
-#ifdef CONFIG_PMAC_BACKLIGHT
-        if (machine_is(powermac) && !blank)
-                set_backlight_enable(1);
-#endif /* CONFIG_PMAC_BACKLIGHT */
+#ifdef CONFIG_FB_ATY128_BACKLIGHT
+        if (machine_is(powermac) && !blank) {
+                down(&fb->bl_dev->sem);
+                fb->bl_dev->props->power = FB_BLANK_UNBLANK;
+                fb->bl_dev->props->update_status(fb->bl_dev);
+                up(&fb->bl_dev->sem);
+        }
+#endif
         return 0;
 }
 
@@ -2138,73 +2333,6 @@ static int aty128fb_ioctl(struct fb_info *info, u_int cmd, u_long arg)
         return -EINVAL;
 }
 
-#ifdef CONFIG_PMAC_BACKLIGHT
-static int backlight_conv[] = {
-        0xff, 0xc0, 0xb5, 0xaa, 0x9f, 0x94, 0x89, 0x7e,
-        0x73, 0x68, 0x5d, 0x52, 0x47, 0x3c, 0x31, 0x24
-};
-
-/* We turn off the LCD completely instead of just dimming the backlight.
- * This provides greater power saving and the display is useless without
- * backlight anyway
- */
-#define BACKLIGHT_LVDS_OFF
-/* That one prevents proper CRT output with LCD off */
-#undef BACKLIGHT_DAC_OFF
-
-static int aty128_set_backlight_enable(int on, int level, void *data)
-{
-        struct aty128fb_par *par = data;
-        unsigned int reg = aty_ld_le32(LVDS_GEN_CNTL);
-
-        if (!par->lcd_on)
-                on = 0;
-        reg |= LVDS_BL_MOD_EN | LVDS_BLON;
-        if (on && level > BACKLIGHT_OFF) {
-                reg |= LVDS_DIGION;
-                if (!(reg & LVDS_ON)) {
-                        reg &= ~LVDS_BLON;
-                        aty_st_le32(LVDS_GEN_CNTL, reg);
-                        (void)aty_ld_le32(LVDS_GEN_CNTL);
-                        mdelay(10);
-                        reg |= LVDS_BLON;
-                        aty_st_le32(LVDS_GEN_CNTL, reg);
-                }
-                reg &= ~LVDS_BL_MOD_LEVEL_MASK;
-                reg |= (backlight_conv[level] << LVDS_BL_MOD_LEVEL_SHIFT);
-#ifdef BACKLIGHT_LVDS_OFF
-                reg |= LVDS_ON | LVDS_EN;
-                reg &= ~LVDS_DISPLAY_DIS;
-#endif
-                aty_st_le32(LVDS_GEN_CNTL, reg);
-#ifdef BACKLIGHT_DAC_OFF
-                aty_st_le32(DAC_CNTL, aty_ld_le32(DAC_CNTL) & (~DAC_PDWN));
-#endif          
-        } else {
-                reg &= ~LVDS_BL_MOD_LEVEL_MASK;
-                reg |= (backlight_conv[0] << LVDS_BL_MOD_LEVEL_SHIFT);
-#ifdef BACKLIGHT_LVDS_OFF
-                reg |= LVDS_DISPLAY_DIS;
-                aty_st_le32(LVDS_GEN_CNTL, reg);
-                (void)aty_ld_le32(LVDS_GEN_CNTL);
-                udelay(10);
-                reg &= ~(LVDS_ON | LVDS_EN | LVDS_BLON | LVDS_DIGION);
-#endif          
-                aty_st_le32(LVDS_GEN_CNTL, reg);
-#ifdef BACKLIGHT_DAC_OFF
-                aty_st_le32(DAC_CNTL, aty_ld_le32(DAC_CNTL) | DAC_PDWN);
-#endif          
-        }
-
-        return 0;
-}
-
-static int aty128_set_backlight_level(int level, void* data)
-{
-        return aty128_set_backlight_enable(1, level, data);
-}
-#endif /* CONFIG_PMAC_BACKLIGHT */
-
 #if 0
     /*
      *  Accelerated functions