backlight: add backlight type

There may be multiple ways of controlling the backlight on a given
machine.  Allow drivers to expose the type of interface they are
providing, making it possible for userspace to make appropriate policy
decisions.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: David Airlie <airlied@linux.ie>
Cc: Alex Deucher <alexdeucher@gmail.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

24 files changed, 46 insertions, 1 deletions

diff --git a/drivers/video/backlight/88pm860x_bl.c b/drivers/video/backlight/88pm860x_bl.c
index b224396b86d5..e59623a15f3f 100644
--- a/drivers/video/backlight/88pm860x_bl.c
+++ b/drivers/video/backlight/88pm860x_bl.c
@@ -227,6 +227,7 @@ static int pm860x_backlight_probe(struct platform_device *pdev)
         }
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = MAX_BRIGHTNESS;
         bl = backlight_device_register(name, &pdev->dev, data,
                                         &pm860x_backlight_ops, &props);
diff --git a/drivers/video/backlight/adp5520_bl.c b/drivers/video/backlight/adp5520_bl.c
index 9f436e014f85..af3119707dbf 100644
--- a/drivers/video/backlight/adp5520_bl.c
+++ b/drivers/video/backlight/adp5520_bl.c
@@ -303,6 +303,7 @@ static int __devinit adp5520_bl_probe(struct platform_device *pdev)
         mutex_init(&data->lock);
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = ADP5020_MAX_BRIGHTNESS;
         bl = backlight_device_register(pdev->name, data->master, data,
                                        &adp5520_bl_ops, &props);
diff --git a/drivers/video/backlight/adp8860_bl.c b/drivers/video/backlight/adp8860_bl.c
index 734c650a47c4..d2a96a421ffd 100644
--- a/drivers/video/backlight/adp8860_bl.c
+++ b/drivers/video/backlight/adp8860_bl.c
@@ -709,6 +709,7 @@ static int __devinit adp8860_probe(struct i2c_client *client,
         i2c_set_clientdata(client, data);
 
         memset(&props, 0, sizeof(props));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = ADP8860_MAX_BRIGHTNESS;
 
         mutex_init(&data->lock);
diff --git a/drivers/video/backlight/adx_bl.c b/drivers/video/backlight/adx_bl.c
index fe9af129c5dd..c861c41af442 100644
--- a/drivers/video/backlight/adx_bl.c
+++ b/drivers/video/backlight/adx_bl.c
@@ -104,6 +104,7 @@ static int __devinit adx_backlight_probe(struct platform_device *pdev)
         }
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = 0xff;
         bldev = backlight_device_register(dev_name(&pdev->dev), &pdev->dev,
                                           bl, &adx_backlight_ops, &props);
diff --git a/drivers/video/backlight/atmel-pwm-bl.c b/drivers/video/backlight/atmel-pwm-bl.c
index e6a66dab088c..0443a4f71858 100644
--- a/drivers/video/backlight/atmel-pwm-bl.c
+++ b/drivers/video/backlight/atmel-pwm-bl.c
@@ -168,6 +168,7 @@ static int atmel_pwm_bl_probe(struct platform_device *pdev)
         }
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = pdata->pwm_duty_max - pdata->pwm_duty_min;
         bldev = backlight_device_register("atmel-pwm-bl", &pdev->dev, pwmbl,
                                           &atmel_pwm_bl_ops, &props);
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index 08703299ef61..80d292fb92d8 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -19,6 +19,12 @@
 #include <asm/backlight.h>
 #endif
 
+static const char const *backlight_types[] = {
+        [BACKLIGHT_RAW] = "raw",
+        [BACKLIGHT_PLATFORM] = "platform",
+        [BACKLIGHT_FIRMWARE] = "firmware",
+};
+
 #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \
                            defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE))
 /* This callback gets called when something important happens inside a
@@ -169,6 +175,14 @@ static ssize_t backlight_store_brightness(struct device *dev,
         return rc;
 }
 
+static ssize_t backlight_show_type(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        struct backlight_device *bd = to_backlight_device(dev);
+
+        return sprintf(buf, "%s\n", backlight_types[bd->props.type]);
+}
+
 static ssize_t backlight_show_max_brightness(struct device *dev,
                 struct device_attribute *attr, char *buf)
 {
@@ -234,6 +248,7 @@ static struct device_attribute bl_device_attributes[] = {
         __ATTR(actual_brightness, 0444, backlight_show_actual_brightness,
                      NULL),
         __ATTR(max_brightness, 0444, backlight_show_max_brightness, NULL),
+        __ATTR(type, 0444, backlight_show_type, NULL),
         __ATTR_NULL,
 };
 
@@ -292,9 +307,16 @@ struct backlight_device *backlight_device_register(const char *name,
         dev_set_drvdata(&new_bd->dev, devdata);
 
         /* Set default properties */
-        if (props)
+        if (props) {
                 memcpy(&new_bd->props, props,
                        sizeof(struct backlight_properties));
+                if (props->type <= 0 || props->type >= BACKLIGHT_TYPE_MAX) {
+                        WARN(1, "%s: invalid backlight type", name);
+                        new_bd->props.type = BACKLIGHT_RAW;
+                }
+        } else {
+                new_bd->props.type = BACKLIGHT_RAW;
+        }
 
         rc = device_register(&new_bd->dev);
         if (rc) {
diff --git a/drivers/video/backlight/corgi_lcd.c b/drivers/video/backlight/corgi_lcd.c
index 1e71c35083bb..af6098396fe6 100644
--- a/drivers/video/backlight/corgi_lcd.c
+++ b/drivers/video/backlight/corgi_lcd.c
@@ -562,6 +562,7 @@ static int __devinit corgi_lcd_probe(struct spi_device *spi)
         lcd->mode = (pdata) ? pdata->init_mode : CORGI_LCD_MODE_VGA;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = pdata->max_intensity;
         lcd->bl_dev = backlight_device_register("corgi_bl", &spi->dev, lcd,
                                                 &corgi_bl_ops, &props);
diff --git a/drivers/video/backlight/cr_bllcd.c b/drivers/video/backlight/cr_bllcd.c
index 397d15eb1ea8..6c8c54041fae 100644
--- a/drivers/video/backlight/cr_bllcd.c
+++ b/drivers/video/backlight/cr_bllcd.c
@@ -193,6 +193,7 @@ static int cr_backlight_probe(struct platform_device *pdev)
         }
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         bdp = backlight_device_register("cr-backlight", &pdev->dev, NULL,
                                         &cr_backlight_ops, &props);
         if (IS_ERR(bdp)) {
diff --git a/drivers/video/backlight/da903x_bl.c b/drivers/video/backlight/da903x_bl.c
index 87659ed79bd7..62043f12a5a4 100644
--- a/drivers/video/backlight/da903x_bl.c
+++ b/drivers/video/backlight/da903x_bl.c
@@ -136,6 +136,7 @@ static int da903x_backlight_probe(struct platform_device *pdev)
                 da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,
                                 DA9034_WLED_ISET(pdata->output_current));
 
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = max_brightness;
         bl = backlight_device_register(pdev->name, data->da903x_dev, data,
                                        &da903x_backlight_ops, &props);
diff --git a/drivers/video/backlight/ep93xx_bl.c b/drivers/video/backlight/ep93xx_bl.c
index b0cc49184803..9f1e389d51d2 100644
--- a/drivers/video/backlight/ep93xx_bl.c
+++ b/drivers/video/backlight/ep93xx_bl.c
@@ -87,6 +87,7 @@ static int __init ep93xxbl_probe(struct platform_device *dev)
         ep93xxbl->mmio = EP93XX_RASTER_BRIGHTNESS;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = EP93XX_MAX_BRIGHT;
         bl = backlight_device_register(dev->name, &dev->dev, ep93xxbl,
                                        &ep93xxbl_ops, &props);
diff --git a/drivers/video/backlight/generic_bl.c b/drivers/video/backlight/generic_bl.c
index 312ca619735d..8c6befd65a33 100644
--- a/drivers/video/backlight/generic_bl.c
+++ b/drivers/video/backlight/generic_bl.c
@@ -91,6 +91,7 @@ static int genericbl_probe(struct platform_device *pdev)
                 name = machinfo->name;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = machinfo->max_intensity;
         bd = backlight_device_register(name, &pdev->dev, NULL, &genericbl_ops,
                                        &props);
diff --git a/drivers/video/backlight/hp680_bl.c b/drivers/video/backlight/hp680_bl.c
index 267d23f8d645..38aa00272141 100644
--- a/drivers/video/backlight/hp680_bl.c
+++ b/drivers/video/backlight/hp680_bl.c
@@ -109,6 +109,7 @@ static int __devinit hp680bl_probe(struct platform_device *pdev)
         struct backlight_device *bd;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = HP680_MAX_INTENSITY;
         bd = backlight_device_register("hp680-bl", &pdev->dev, NULL,
                                        &hp680bl_ops, &props);
diff --git a/drivers/video/backlight/jornada720_bl.c b/drivers/video/backlight/jornada720_bl.c
index 2f177b3a4885..40e4fa8fcf92 100644
--- a/drivers/video/backlight/jornada720_bl.c
+++ b/drivers/video/backlight/jornada720_bl.c
@@ -106,6 +106,7 @@ static int jornada_bl_probe(struct platform_device *pdev)
         struct backlight_device *bd;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = BL_MAX_BRIGHT;
         bd = backlight_device_register(S1D_DEVICENAME, &pdev->dev, NULL,
                                        &jornada_bl_ops, &props);
diff --git a/drivers/video/backlight/kb3886_bl.c b/drivers/video/backlight/kb3886_bl.c
index f439a8632287..72dd5556a35b 100644
--- a/drivers/video/backlight/kb3886_bl.c
+++ b/drivers/video/backlight/kb3886_bl.c
@@ -149,6 +149,7 @@ static int kb3886bl_probe(struct platform_device *pdev)
                 machinfo->limit_mask = -1;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = machinfo->max_intensity;
         kb3886_backlight_device = backlight_device_register("kb3886-bl",
                                                             &pdev->dev, NULL,
diff --git a/drivers/video/backlight/locomolcd.c b/drivers/video/backlight/locomolcd.c
index d2f59015d517..bbca3127071e 100644
--- a/drivers/video/backlight/locomolcd.c
+++ b/drivers/video/backlight/locomolcd.c
@@ -184,6 +184,7 @@ static int locomolcd_probe(struct locomo_dev *ldev)
         local_irq_restore(flags);
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = 4;
         locomolcd_bl_device = backlight_device_register("locomo-bl",
                                                         &ldev->dev, NULL,
diff --git a/drivers/video/backlight/max8925_bl.c b/drivers/video/backlight/max8925_bl.c
index 209acc105cbc..07e8e273ced0 100644
--- a/drivers/video/backlight/max8925_bl.c
+++ b/drivers/video/backlight/max8925_bl.c
@@ -136,6 +136,7 @@ static int __devinit max8925_backlight_probe(struct platform_device *pdev)
         data->current_brightness = 0;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = MAX_BRIGHTNESS;
         bl = backlight_device_register(name, &pdev->dev, data,
                                         &max8925_backlight_ops, &props);
diff --git a/drivers/video/backlight/mbp_nvidia_bl.c b/drivers/video/backlight/mbp_nvidia_bl.c
index 1485f7345f49..74c33944aa86 100644
--- a/drivers/video/backlight/mbp_nvidia_bl.c
+++ b/drivers/video/backlight/mbp_nvidia_bl.c
@@ -367,6 +367,7 @@ static int __init mbp_init(void)
                 return -ENXIO;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_PLATFORM;
         props.max_brightness = 15;
         mbp_backlight_device = backlight_device_register("mbp_backlight", NULL,
                                                          NULL,
diff --git a/drivers/video/backlight/omap1_bl.c b/drivers/video/backlight/omap1_bl.c
index d3bc56296c8d..08d26a72394c 100644
--- a/drivers/video/backlight/omap1_bl.c
+++ b/drivers/video/backlight/omap1_bl.c
@@ -146,6 +146,7 @@ static int omapbl_probe(struct platform_device *pdev)
                 return -ENOMEM;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = OMAPBL_MAX_INTENSITY;
         dev = backlight_device_register("omap-bl", &pdev->dev, bl, &omapbl_ops,
                                         &props);
diff --git a/drivers/video/backlight/pcf50633-backlight.c b/drivers/video/backlight/pcf50633-backlight.c
index 3c424f7efdcc..ef5628d60563 100644
--- a/drivers/video/backlight/pcf50633-backlight.c
+++ b/drivers/video/backlight/pcf50633-backlight.c
@@ -112,6 +112,7 @@ static int __devinit pcf50633_bl_probe(struct platform_device *pdev)
         if (!pcf_bl)
                 return -ENOMEM;
 
+        bl_props.type = BACKLIGHT_RAW;
         bl_props.max_brightness = 0x3f;
         bl_props.power = FB_BLANK_UNBLANK;
 
diff --git a/drivers/video/backlight/progear_bl.c b/drivers/video/backlight/progear_bl.c
index 809278c90738..6af183d6465e 100644
--- a/drivers/video/backlight/progear_bl.c
+++ b/drivers/video/backlight/progear_bl.c
@@ -84,6 +84,7 @@ static int progearbl_probe(struct platform_device *pdev)
         pci_write_config_byte(sb_dev, SB_MPS1, temp | 0x20);
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = HW_LEVEL_MAX - HW_LEVEL_MIN;
         progear_backlight_device = backlight_device_register("progear-bl",
                                                              &pdev->dev, NULL,
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 21866ec69656..2c2a2c703c14 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -108,6 +108,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
                 dev_dbg(&pdev->dev, "got pwm for backlight\n");
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = data->max_brightness;
         bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, pb,
                                        &pwm_backlight_ops, &props);
diff --git a/drivers/video/backlight/s6e63m0.c b/drivers/video/backlight/s6e63m0.c
index 5927db0da999..322040f686c2 100644
--- a/drivers/video/backlight/s6e63m0.c
+++ b/drivers/video/backlight/s6e63m0.c
@@ -778,6 +778,7 @@ static int __devinit s6e63m0_probe(struct spi_device *spi)
 
         bd->props.max_brightness = MAX_BRIGHTNESS;
         bd->props.brightness = MAX_BRIGHTNESS;
+        bd->props.type = BACKLIGHT_RAW;
         lcd->bd = bd;
 
         /*
diff --git a/drivers/video/backlight/tosa_bl.c b/drivers/video/backlight/tosa_bl.c
index 2a04b382ec48..425a7365470b 100644
--- a/drivers/video/backlight/tosa_bl.c
+++ b/drivers/video/backlight/tosa_bl.c
@@ -102,6 +102,7 @@ static int __devinit tosa_bl_probe(struct i2c_client *client,
         data->i2c = client;
 
         memset(&props, 0, sizeof(struct backlight_properties));
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = 512 - 1;
         data->bl = backlight_device_register("tosa-bl", &client->dev, data,
                                              &bl_ops, &props);
diff --git a/drivers/video/backlight/wm831x_bl.c b/drivers/video/backlight/wm831x_bl.c
index 08fd87f3aecc..d4c6eb248ff9 100644
--- a/drivers/video/backlight/wm831x_bl.c
+++ b/drivers/video/backlight/wm831x_bl.c
@@ -193,6 +193,7 @@ static int wm831x_backlight_probe(struct platform_device *pdev)
         data->current_brightness = 0;
         data->isink_reg = isink_reg;
 
+        props.type = BACKLIGHT_RAW;
         props.max_brightness = max_isel;
         bl = backlight_device_register("wm831x", &pdev->dev, data,
                                        &wm831x_backlight_ops, &props);