2010-11-19 15:56:33

by Matthew Garrett

[permalink] [raw]
Subject: [PATCH 1/5] 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 <[email protected]>
Cc: Richard Purdie <[email protected]>
Cc: [email protected]
Cc: [email protected]
---
Documentation/ABI/stable/sysfs-class-backlight | 20 ++++++++++++++++++++
drivers/acpi/video.c | 1 +
drivers/gpu/drm/nouveau/nouveau_backlight.c | 2 ++
drivers/hid/hid-picolcd.c | 1 +
drivers/macintosh/via-pmu-backlight.c | 1 +
drivers/platform/x86/acer-wmi.c | 1 +
drivers/platform/x86/asus-laptop.c | 1 +
drivers/platform/x86/asus_acpi.c | 1 +
drivers/platform/x86/classmate-laptop.c | 1 +
drivers/platform/x86/compal-laptop.c | 1 +
drivers/platform/x86/dell-laptop.c | 1 +
drivers/platform/x86/eeepc-laptop.c | 1 +
drivers/platform/x86/eeepc-wmi.c | 1 +
drivers/platform/x86/fujitsu-laptop.c | 1 +
drivers/platform/x86/msi-laptop.c | 1 +
drivers/platform/x86/msi-wmi.c | 1 +
drivers/platform/x86/panasonic-laptop.c | 1 +
drivers/platform/x86/sony-laptop.c | 1 +
drivers/platform/x86/thinkpad_acpi.c | 1 +
drivers/platform/x86/toshiba_acpi.c | 1 +
drivers/staging/olpc_dcon/olpc_dcon.c | 1 +
drivers/staging/samsung-laptop/samsung-laptop.c | 1 +
drivers/usb/misc/appledisplay.c | 1 +
drivers/video/atmel_lcdfb.c | 1 +
drivers/video/aty/aty128fb.c | 1 +
drivers/video/aty/atyfb_base.c | 1 +
drivers/video/aty/radeon_backlight.c | 1 +
drivers/video/backlight/88pm860x_bl.c | 1 +
drivers/video/backlight/adp5520_bl.c | 1 +
drivers/video/backlight/adp8860_bl.c | 1 +
drivers/video/backlight/adx_bl.c | 1 +
drivers/video/backlight/atmel-pwm-bl.c | 1 +
drivers/video/backlight/backlight.c | 15 +++++++++++++++
drivers/video/backlight/corgi_lcd.c | 1 +
drivers/video/backlight/cr_bllcd.c | 1 +
drivers/video/backlight/da903x_bl.c | 1 +
drivers/video/backlight/ep93xx_bl.c | 1 +
drivers/video/backlight/generic_bl.c | 1 +
drivers/video/backlight/hp680_bl.c | 1 +
drivers/video/backlight/jornada720_bl.c | 1 +
drivers/video/backlight/kb3886_bl.c | 1 +
drivers/video/backlight/locomolcd.c | 1 +
drivers/video/backlight/max8925_bl.c | 1 +
drivers/video/backlight/mbp_nvidia_bl.c | 1 +
drivers/video/backlight/omap1_bl.c | 1 +
drivers/video/backlight/pcf50633-backlight.c | 1 +
drivers/video/backlight/progear_bl.c | 1 +
drivers/video/backlight/pwm_bl.c | 1 +
drivers/video/backlight/s6e63m0.c | 1 +
drivers/video/backlight/tosa_bl.c | 1 +
drivers/video/backlight/wm831x_bl.c | 1 +
drivers/video/bf54x-lq043fb.c | 1 +
drivers/video/bfin-t350mcqb-fb.c | 1 +
drivers/video/imxfb.c | 1 +
drivers/video/nvidia/nv_backlight.c | 1 +
drivers/video/omap2/displays/panel-acx565akm.c | 1 +
.../video/omap2/displays/panel-sharp-ls037v7dw01.c | 1 +
drivers/video/omap2/displays/panel-taal.c | 2 ++
drivers/video/riva/fbdev.c | 1 +
include/linux/backlight.h | 8 ++++++++
60 files changed, 102 insertions(+), 0 deletions(-)

diff --git a/Documentation/ABI/stable/sysfs-class-backlight b/Documentation/ABI/stable/sysfs-class-backlight
index 4d637e1..70302f3 100644
--- a/Documentation/ABI/stable/sysfs-class-backlight
+++ b/Documentation/ABI/stable/sysfs-class-backlight
@@ -34,3 +34,23 @@ Contact: Richard Purdie <[email protected]>
Description:
Maximum brightness for <backlight>.
Users: HAL
+
+What: /sys/class/backlight/<backlight>/type
+Date: September 2010
+KernelVersion: 2.6.37
+Contact: Matthew Garrett <[email protected]>
+Description:
+ The type of interface controlled by <backlight>.
+ "firmware": The driver uses a standard firmware interface
+ "platform": The driver uses a platform-specific interface
+ "raw": The driver controls hardware registers directly
+
+ In the general case, when multiple backlight
+ interfaces are available for a single device, firmware
+ control should be preferred to platform control should
+ be preferred to raw control. Using a firmware
+ interface reduces the probability of confusion with
+ the hardware and the OS independently updating the
+ backlight state. Platform interfaces are mostly a
+ holdover from pre-standardisation of firmware
+ interfaces.
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 5cd0228..38165a8 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -856,6 +856,7 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
count++;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_FIRMWARE;
props.max_brightness = device->brightness->count - 3;
device->backlight = backlight_device_register(name, NULL, device,
&acpi_backlight_ops,
diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c
index 406228f..9485af3 100644
--- a/drivers/gpu/drm/nouveau/nouveau_backlight.c
+++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c
@@ -97,6 +97,7 @@ static int nouveau_nv40_backlight_init(struct drm_device *dev)
return 0;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 31;
bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
&nv40_bl_ops, &props);
@@ -120,6 +121,7 @@ static int nouveau_nv50_backlight_init(struct drm_device *dev)
return 0;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 1025;
bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
&nv50_bl_ops, &props);
diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c
index bc2e077..3418b82 100644
--- a/drivers/hid/hid-picolcd.c
+++ b/drivers/hid/hid-picolcd.c
@@ -944,6 +944,7 @@ static int picolcd_init_backlight(struct picolcd_data *data, struct hid_report *
}

memset(&props, 0, sizeof(props));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 0xff;
bdev = backlight_device_register(dev_name(dev), dev, data,
&picolcd_blops, &props);
diff --git a/drivers/macintosh/via-pmu-backlight.c b/drivers/macintosh/via-pmu-backlight.c
index 1cec02f..364a295 100644
--- a/drivers/macintosh/via-pmu-backlight.c
+++ b/drivers/macintosh/via-pmu-backlight.c
@@ -163,6 +163,7 @@ void __init pmu_backlight_init()
snprintf(name, sizeof(name), "pmubl");

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, NULL, NULL, &pmu_backlight_data,
&props);
diff --git a/drivers/platform/x86/acer-wmi.c b/drivers/platform/x86/acer-wmi.c
index c8c6537..3d3fcfc 100644
--- a/drivers/platform/x86/acer-wmi.c
+++ b/drivers/platform/x86/acer-wmi.c
@@ -926,6 +926,7 @@ static int __devinit acer_backlight_init(struct device *dev)
struct backlight_device *bd;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = max_brightness;
bd = backlight_device_register("acer-wmi", dev, NULL, &acer_bl_ops,
&props);
diff --git a/drivers/platform/x86/asus-laptop.c b/drivers/platform/x86/asus-laptop.c
index 60a5a5c..60b0159 100644
--- a/drivers/platform/x86/asus-laptop.c
+++ b/drivers/platform/x86/asus-laptop.c
@@ -648,6 +648,7 @@ static int asus_backlight_init(struct asus_laptop *asus)

memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = 15;
+ props.type = BACKLIGHT_PLATFORM;

bd = backlight_device_register(ASUS_LAPTOP_FILE,
&asus->platform_device->dev, asus,
diff --git a/drivers/platform/x86/asus_acpi.c b/drivers/platform/x86/asus_acpi.c
index ca05aef..3ea8df5 100644
--- a/drivers/platform/x86/asus_acpi.c
+++ b/drivers/platform/x86/asus_acpi.c
@@ -1513,6 +1513,7 @@ static int __init asus_acpi_init(void)
}

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = 15;
asus_backlight_device = backlight_device_register("asus", NULL, NULL,
&asus_backlight_data,
diff --git a/drivers/platform/x86/classmate-laptop.c b/drivers/platform/x86/classmate-laptop.c
index 341cbfe..0ade3a4 100644
--- a/drivers/platform/x86/classmate-laptop.c
+++ b/drivers/platform/x86/classmate-laptop.c
@@ -562,6 +562,7 @@ static int cmpc_ipml_add(struct acpi_device *acpi)
return -ENOMEM;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = 7;
ipml->bd = backlight_device_register("cmpc_bl", &acpi->dev,
acpi->handle, &cmpc_bl_ops,
diff --git a/drivers/platform/x86/compal-laptop.c b/drivers/platform/x86/compal-laptop.c
index 097083c..1e66477 100644
--- a/drivers/platform/x86/compal-laptop.c
+++ b/drivers/platform/x86/compal-laptop.c
@@ -962,6 +962,7 @@ static int __init compal_init(void)
if (!acpi_video_backlight_support()) {
struct backlight_properties props;
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = BACKLIGHT_LEVEL_MAX;
compalbl_device = backlight_device_register(DRIVER_NAME,
NULL, NULL,
diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index cf8a89a..3a54613 100644
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -651,6 +651,7 @@ static int __init dell_init(void)
if (max_intensity) {
struct backlight_properties props;
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = max_intensity;
dell_backlight_device = backlight_device_register("dell_backlight",
&platform_device->dev,
diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
index b2edfdc..697505b 100644
--- a/drivers/platform/x86/eeepc-laptop.c
+++ b/drivers/platform/x86/eeepc-laptop.c
@@ -1136,6 +1136,7 @@ static int eeepc_backlight_init(struct eeepc_laptop *eeepc)
struct backlight_device *bd;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = 15;
bd = backlight_device_register(EEEPC_LAPTOP_FILE,
&eeepc->platform_device->dev, eeepc,
diff --git a/drivers/platform/x86/eeepc-wmi.c b/drivers/platform/x86/eeepc-wmi.c
index 462ceab..29f607b 100644
--- a/drivers/platform/x86/eeepc-wmi.c
+++ b/drivers/platform/x86/eeepc-wmi.c
@@ -233,6 +233,7 @@ static int eeepc_wmi_backlight_init(struct eeepc_wmi *eeepc)

memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = 15;
+ props.type = BACKLIGHT_PLATFORM;
bd = backlight_device_register(EEEPC_WMI_FILE,
&platform_device->dev, eeepc,
&eeepc_wmi_bl_ops, &props);
diff --git a/drivers/platform/x86/fujitsu-laptop.c b/drivers/platform/x86/fujitsu-laptop.c
index f44cd26..f5376c6 100644
--- a/drivers/platform/x86/fujitsu-laptop.c
+++ b/drivers/platform/x86/fujitsu-laptop.c
@@ -1128,6 +1128,7 @@ static int __init fujitsu_init(void)

memset(&props, 0, sizeof(struct backlight_properties));
max_brightness = fujitsu->max_brightness;
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = max_brightness - 1;
fujitsu->bl_device = backlight_device_register("fujitsu-laptop",
NULL, NULL,
diff --git a/drivers/platform/x86/msi-laptop.c b/drivers/platform/x86/msi-laptop.c
index 7e9bb6d..142d385 100644
--- a/drivers/platform/x86/msi-laptop.c
+++ b/drivers/platform/x86/msi-laptop.c
@@ -804,6 +804,7 @@ static int __init msi_init(void)
} else {
struct backlight_properties props;
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = MSI_LCD_LEVEL_MAX - 1;
msibl_device = backlight_device_register("msi-laptop-bl", NULL,
NULL, &msibl_ops,
diff --git a/drivers/platform/x86/msi-wmi.c b/drivers/platform/x86/msi-wmi.c
index 42a5469..064d8d6 100644
--- a/drivers/platform/x86/msi-wmi.c
+++ b/drivers/platform/x86/msi-wmi.c
@@ -252,6 +252,7 @@ static int __init msi_wmi_init(void)
if (!acpi_video_backlight_support()) {
struct backlight_properties props;
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
backlight = backlight_device_register(DRV_NAME, NULL, NULL,
&msi_backlight_ops,
diff --git a/drivers/platform/x86/panasonic-laptop.c b/drivers/platform/x86/panasonic-laptop.c
index cc1e0ba..05be30e 100644
--- a/drivers/platform/x86/panasonic-laptop.c
+++ b/drivers/platform/x86/panasonic-laptop.c
@@ -602,6 +602,7 @@ static int acpi_pcc_hotkey_add(struct acpi_device *device)
}
/* initialize backlight */
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = pcc->sinf[SINF_AC_MAX_BRIGHT];
pcc->backlight = backlight_device_register("panasonic", NULL, pcc,
&pcc_backlight_ops, &props);
diff --git a/drivers/platform/x86/sony-laptop.c b/drivers/platform/x86/sony-laptop.c
index f200677..138d8ab 100644
--- a/drivers/platform/x86/sony-laptop.c
+++ b/drivers/platform/x86/sony-laptop.c
@@ -1297,6 +1297,7 @@ static int sony_nc_add(struct acpi_device *device)
&handle))) {
struct backlight_properties props;
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = SONY_MAX_BRIGHTNESS - 1;
sony_backlight_device = backlight_device_register("sony", NULL,
NULL,
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 2d61186..6dedc97 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -6310,6 +6310,7 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
return 1;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = bright_maxlvl;
props.brightness = b & TP_EC_BACKLIGHT_LVLMSK;
ibm_backlight_device = backlight_device_register(TPACPI_BACKLIGHT_DEV_NAME,
diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 06f304f..a5533a1 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -1017,6 +1017,7 @@ static int __init toshiba_acpi_init(void)
create_toshiba_proc_entries();
}

+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS - 1;
toshiba_backlight_device = backlight_device_register("toshiba",
&toshiba_acpi.p_dev->dev,
diff --git a/drivers/staging/olpc_dcon/olpc_dcon.c b/drivers/staging/olpc_dcon/olpc_dcon.c
index 75aa7a36..a5915f4 100644
--- a/drivers/staging/olpc_dcon/olpc_dcon.c
+++ b/drivers/staging/olpc_dcon/olpc_dcon.c
@@ -718,6 +718,7 @@ static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
}
else {
dcon_bl_dev->props.max_brightness = 15;
+ dcon_bl_dev->props.type = BACKLIGHT_RAW;
dcon_bl_dev->props.power = FB_BLANK_UNBLANK;
dcon_bl_dev->props.brightness = dcon_get_backlight();

diff --git a/drivers/staging/samsung-laptop/samsung-laptop.c b/drivers/staging/samsung-laptop/samsung-laptop.c
index eb44b60..6c55f38 100644
--- a/drivers/staging/samsung-laptop/samsung-laptop.c
+++ b/drivers/staging/samsung-laptop/samsung-laptop.c
@@ -488,6 +488,7 @@ static int __init samsung_init(void)

/* create a backlight device to talk to this one */
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_PLATFORM;
props.max_brightness = MAX_BRIGHT;
backlight_device = backlight_device_register("samsung", &sdev->dev,
NULL, &backlight_ops,
diff --git a/drivers/usb/misc/appledisplay.c b/drivers/usb/misc/appledisplay.c
index 1fa6ce3..68ab460 100644
--- a/drivers/usb/misc/appledisplay.c
+++ b/drivers/usb/misc/appledisplay.c
@@ -282,6 +282,7 @@ static int appledisplay_probe(struct usb_interface *iface,
snprintf(bl_name, sizeof(bl_name), "appledisplay%d",
atomic_inc_return(&count_displays) - 1);
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 0xff;
pdata->bd = backlight_device_register(bl_name, NULL, pdata,
&appledisplay_bl_data, &props);
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 8dce251..7d40604 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -127,6 +127,7 @@ static void init_backlight(struct atmel_lcdfb_info *sinfo)
return;

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 0xff;
bl = backlight_device_register("backlight", &sinfo->pdev->dev, sinfo,
&atmel_lcdc_bl_ops, &props);
diff --git a/drivers/video/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 34a0851..ac3b7e3 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -1818,6 +1818,7 @@ static void aty128_bl_init(struct aty128fb_par *par)
snprintf(name, sizeof(name), "aty128bl%d", info->node);

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, info->dev, par, &aty128_bl_data,
&props);
diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 5bf9123..9f9deb5 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -2241,6 +2241,7 @@ static void aty_bl_init(struct atyfb_par *par)
snprintf(name, sizeof(name), "atybl%d", info->node);

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, info->dev, par, &aty_bl_data,
&props);
diff --git a/drivers/video/aty/radeon_backlight.c b/drivers/video/aty/radeon_backlight.c
index 256966e..732f665 100644
--- a/drivers/video/aty/radeon_backlight.c
+++ b/drivers/video/aty/radeon_backlight.c
@@ -158,6 +158,7 @@ void radeonfb_bl_init(struct radeonfb_info *rinfo)
snprintf(name, sizeof(name), "radeonbl%d", rinfo->info->node);

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, rinfo->info->dev, pdata,
&radeon_bl_data, &props);
diff --git a/drivers/video/backlight/88pm860x_bl.c b/drivers/video/backlight/88pm860x_bl.c
index 38ffc3f..d5e51e2 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 9f436e0..af31197 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 734c650..d2a96a4 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 fe9af12..c861c41 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 e6a66da..0443a4f 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 e207810..074502c 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 *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,
};

diff --git a/drivers/video/backlight/corgi_lcd.c b/drivers/video/backlight/corgi_lcd.c
index 1e71c35..af60983 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 a4f4546..d7d1673 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 87659ed..62043f1 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 b0cc491..9f1e389 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 312ca61..8c6befd 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 267d23f..38aa002 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 2f177b3..40e4fa8 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 f439a86..72dd555 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 d2f5901..bbca312 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 b2b2c7b..8d25610 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 1485f73..74c3394 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 d3bc562..08d26a7 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 3c424f7..ef5628d 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 809278c..6af183d 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 21866ec..2c2a2c7 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 5927db0..322040f 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 2a04b38..425a736 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 08fd87f..d4c6eb2 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);
diff --git a/drivers/video/bf54x-lq043fb.c b/drivers/video/bf54x-lq043fb.c
index e7d0f52..2464b91 100644
--- a/drivers/video/bf54x-lq043fb.c
+++ b/drivers/video/bf54x-lq043fb.c
@@ -649,6 +649,7 @@ static int __devinit bfin_bf54x_probe(struct platform_device *pdev)
}
#ifndef NO_BL_SUPPORT
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 255;
bl_dev = backlight_device_register("bf54x-bl", NULL, NULL,
&bfin_lq043fb_bl_ops, &props);
diff --git a/drivers/video/bfin-t350mcqb-fb.c b/drivers/video/bfin-t350mcqb-fb.c
index 3cf7767..d8de29f 100644
--- a/drivers/video/bfin-t350mcqb-fb.c
+++ b/drivers/video/bfin-t350mcqb-fb.c
@@ -545,6 +545,7 @@ static int __devinit bfin_t350mcqb_probe(struct platform_device *pdev)
}
#ifndef NO_BL_SUPPORT
memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = 255;
bl_dev = backlight_device_register("bf52x-bl", NULL, NULL,
&bfin_lq043fb_bl_ops, &props);
diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index 5c363d0..01d1793 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -502,6 +502,7 @@ static void imxfb_init_backlight(struct imxfb_info *fbi)

memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = 0xff;
+ props.type = BACKLIGHT_RAW;
writel(fbi->pwmr, fbi->regs + LCDC_PWMR);

bl = backlight_device_register("imxfb-bl", &fbi->pdev->dev, fbi,
diff --git a/drivers/video/nvidia/nv_backlight.c b/drivers/video/nvidia/nv_backlight.c
index 2fb552a..74ba5da 100644
--- a/drivers/video/nvidia/nv_backlight.c
+++ b/drivers/video/nvidia/nv_backlight.c
@@ -111,6 +111,7 @@ void nvidia_bl_init(struct nvidia_par *par)
snprintf(name, sizeof(name), "nvidiabl%d", info->node);

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, info->dev, par, &nvidia_bl_ops,
&props);
diff --git a/drivers/video/omap2/displays/panel-acx565akm.c b/drivers/video/omap2/displays/panel-acx565akm.c
index e773106..7e04c92 100644
--- a/drivers/video/omap2/displays/panel-acx565akm.c
+++ b/drivers/video/omap2/displays/panel-acx565akm.c
@@ -534,6 +534,7 @@ static int acx_panel_probe(struct omap_dss_device *dssdev)

props.fb_blank = FB_BLANK_UNBLANK;
props.power = FB_BLANK_UNBLANK;
+ props.type = BACKLIGHT_RAW;

bldev = backlight_device_register("acx565akm", &md->spi->dev,
md, &acx565akm_bl_ops, &props);
diff --git a/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c b/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
index 9a138f6..d2b35d2 100644
--- a/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
+++ b/drivers/video/omap2/displays/panel-sharp-ls037v7dw01.c
@@ -99,6 +99,7 @@ static int sharp_ls_panel_probe(struct omap_dss_device *dssdev)

memset(&props, 0, sizeof(struct backlight_properties));
props.max_brightness = dssdev->max_backlight_level;
+ props.type = BACKLIGHT_RAW;

bl = backlight_device_register("sharp-ls", &dssdev->dev, dssdev,
&sharp_ls_bl_ops, &props);
diff --git a/drivers/video/omap2/displays/panel-taal.c b/drivers/video/omap2/displays/panel-taal.c
index e1c765d..d16a7cd 100644
--- a/drivers/video/omap2/displays/panel-taal.c
+++ b/drivers/video/omap2/displays/panel-taal.c
@@ -729,6 +729,8 @@ static int taal_probe(struct omap_dss_device *dssdev)
props.max_brightness = 255;
else
props.max_brightness = 127;
+
+ props.type = BACKLIGHT_RAW;
bldev = backlight_device_register("taal", &dssdev->dev, dssdev,
&taal_bl_ops, &props);
if (IS_ERR(bldev)) {
diff --git a/drivers/video/riva/fbdev.c b/drivers/video/riva/fbdev.c
index 618f36b..9058ba5 100644
--- a/drivers/video/riva/fbdev.c
+++ b/drivers/video/riva/fbdev.c
@@ -355,6 +355,7 @@ static void riva_bl_init(struct riva_par *par)
snprintf(name, sizeof(name), "rivabl%d", info->node);

memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
props.max_brightness = FB_BACKLIGHT_LEVELS - 1;
bd = backlight_device_register(name, info->dev, par, &riva_bl_ops,
&props);
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index 4a3d52e..5b45437 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -32,6 +32,12 @@ enum backlight_update_reason {
BACKLIGHT_UPDATE_SYSFS,
};

+enum backlight_type {
+ BACKLIGHT_RAW,
+ BACKLIGHT_PLATFORM,
+ BACKLIGHT_FIRMWARE,
+};
+
struct backlight_device;
struct fb_info;

@@ -62,6 +68,8 @@ struct backlight_properties {
/* FB Blanking active? (values as for power) */
/* Due to be removed, please use (state & BL_CORE_FBBLANK) */
int fb_blank;
+ /* Backlight type */
+ enum backlight_type type;
/* Flags used to signal drivers of state changes */
/* Upper 4 bits are reserved for driver internal use */
unsigned int state;
--
1.7.3.2


2010-11-19 15:55:29

by Matthew Garrett

[permalink] [raw]
Subject: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

Dual-GPU machines may provide more than one ACPI backlight interface. Tie
the backlight device to the GPU in order to allow userspace to identify
the correct interface.

Signed-off-by: Matthew Garrett <[email protected]>
---
drivers/acpi/video.c | 15 ++++++++++++++-
1 files changed, 14 insertions(+), 1 deletions(-)

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index 38165a8..0403647 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -843,6 +843,9 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)

if (acpi_video_backlight_support()) {
struct backlight_properties props;
+ struct pci_dev *pdev;
+ acpi_handle acpi_parent;
+ struct device *parent = NULL;
int result;
static int count = 0;
char *name;
@@ -855,10 +858,20 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
return;
count++;

+ acpi_get_parent(device->dev->handle, &acpi_parent);
+
+ pdev = acpi_get_pci_dev(acpi_parent);
+ if (pdev) {
+ parent = &pdev->dev;
+ pci_dev_put(pdev);
+ }
+
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_FIRMWARE;
props.max_brightness = device->brightness->count - 3;
- device->backlight = backlight_device_register(name, NULL, device,
+ device->backlight = backlight_device_register(name,
+ parent,
+ device,
&acpi_backlight_ops,
&props);
kfree(name);
--
1.7.3.2

2010-11-19 15:55:31

by Matthew Garrett

[permalink] [raw]
Subject: [PATCH 2/5] i915: Add native backlight control

Not all systems expose a firmware or platform mechanism for changing the
backlight intensity on i915, so add native driver support.

Signed-off-by: Matthew Garrett <[email protected]>
Cc: intel-gfx <[email protected]>
---
drivers/gpu/drm/i915/i915_drv.h | 4 ++
drivers/gpu/drm/i915/intel_dp.c | 7 +++
drivers/gpu/drm/i915/intel_drv.h | 2 +
drivers/gpu/drm/i915/intel_lvds.c | 5 ++
drivers/gpu/drm/i915/intel_opregion.c | 1 -
drivers/gpu/drm/i915/intel_panel.c | 67 +++++++++++++++++++++++++++++++++
6 files changed, 85 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 90414ae..f311ce4 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -36,6 +36,7 @@
#include <linux/io-mapping.h>
#include <linux/i2c.h>
#include <drm/intel-gtt.h>
+#include <linux/backlight.h>

/* General customization:
*/
@@ -679,6 +680,7 @@ typedef struct drm_i915_private {
int child_dev_num;
struct child_device_config *child_dev;
struct drm_connector *int_lvds_connector;
+ struct drm_connector *int_edp_connector;

bool mchbar_need_disable;

@@ -707,6 +709,8 @@ typedef struct drm_i915_private {

/* list of fbdev register on this device */
struct intel_fbdev *fbdev;
+
+ struct backlight_device *backlight;
} drm_i915_private_t;

/** driver private structure attached to each drm_gem_object */
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index c8e0055..7cfefb5 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1639,6 +1639,11 @@ done:
static void
intel_dp_destroy (struct drm_connector *connector)
{
+ struct drm_device *dev = connector->dev;
+
+ if (intel_dpd_is_edp(dev))
+ intel_panel_backlight_destroy(dev);
+
drm_sysfs_connector_remove(connector);
drm_connector_cleanup(connector);
kfree(connector);
@@ -1868,6 +1873,8 @@ intel_dp_init(struct drm_device *dev, int output_reg)
DRM_MODE_TYPE_PREFERRED;
}
}
+ dev_priv->int_edp_connector = connector;
+ intel_panel_backlight_setup(dev);
}

intel_dp_add_properties(intel_dp, connector);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 21551fe..7917bec 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -256,6 +256,8 @@ extern void intel_pch_panel_fitting(struct drm_device *dev,
extern u32 intel_panel_get_max_backlight(struct drm_device *dev);
extern u32 intel_panel_get_backlight(struct drm_device *dev);
extern void intel_panel_set_backlight(struct drm_device *dev, u32 level);
+extern int intel_panel_backlight_setup(struct drm_device *dev);
+extern void intel_panel_backlight_destroy(struct drm_device *dev);

extern void intel_crtc_load_lut(struct drm_crtc *crtc);
extern void intel_encoder_prepare (struct drm_encoder *encoder);
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 4324a32..f69a7b8 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -569,6 +569,8 @@ static void intel_lvds_destroy(struct drm_connector *connector)
struct drm_device *dev = connector->dev;
struct drm_i915_private *dev_priv = dev->dev_private;

+ intel_panel_backlight_destroy(dev);
+
if (dev_priv->lid_notifier.notifier_call)
acpi_lid_notifier_unregister(&dev_priv->lid_notifier);
drm_sysfs_connector_remove(connector);
@@ -1026,6 +1028,9 @@ out:
/* keep the LVDS connector */
dev_priv->int_lvds_connector = connector;
drm_sysfs_connector_add(connector);
+
+ intel_panel_backlight_setup(dev);
+
return;

failed:
diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c
index 9b0d9a8..bf79c02 100644
--- a/drivers/gpu/drm/i915/intel_opregion.c
+++ b/drivers/gpu/drm/i915/intel_opregion.c
@@ -224,7 +224,6 @@ void intel_opregion_asle_intr(struct drm_device *dev)
asle->aslc = asle_stat;
}

-/* Only present on Ironlake+ */
void intel_opregion_gse_intr(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 92ff8f3..1eaa66e 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -218,3 +218,70 @@ void intel_panel_set_backlight(struct drm_device *dev, u32 level)
tmp &= ~BACKLIGHT_DUTY_CYCLE_MASK;
I915_WRITE(BLC_PWM_CTL, tmp | level);
}
+
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+static int intel_panel_update_status(struct backlight_device *bd)
+{
+ struct drm_device *dev = bl_get_data(bd);
+ intel_panel_set_backlight(dev, bd->props.brightness);
+ return 0;
+}
+
+static int intel_panel_get_brightness(struct backlight_device *bd)
+{
+ struct drm_device *dev = bl_get_data(bd);
+ return intel_panel_get_backlight(dev);
+}
+
+static const struct backlight_ops intel_panel_bl_ops = {
+ .update_status = intel_panel_update_status,
+ .get_brightness = intel_panel_get_brightness,
+};
+
+int intel_panel_backlight_setup(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct backlight_properties props;
+ struct drm_connector *connector;
+
+ if (dev_priv->int_lvds_connector)
+ connector = dev_priv->int_lvds_connector;
+ else if (dev_priv->int_edp_connector)
+ connector = dev_priv->int_edp_connector;
+ else
+ return -ENODEV;
+
+ props.type = BACKLIGHT_RAW;
+ props.max_brightness = intel_panel_get_max_backlight(dev);
+ dev_priv->backlight =
+ backlight_device_register("intel_backlight",
+ &connector->kdev, dev,
+ &intel_panel_bl_ops, &props);
+
+ if (IS_ERR(dev_priv->backlight)) {
+ DRM_ERROR("Failed to register backlight: %ld\n",
+ PTR_ERR(dev_priv->backlight));
+ dev_priv->backlight = NULL;
+ return -ENODEV;
+ }
+ dev_priv->backlight->props.brightness = intel_panel_get_backlight(dev);
+ return 0;
+}
+
+void intel_panel_backlight_destroy(struct drm_device *dev)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ if (dev_priv->backlight)
+ backlight_device_unregister(dev_priv->backlight);
+}
+#else
+int intel_panel_backlight_setup(struct drm_device *dev)
+{
+ return 0;
+}
+
+void intel_panel_backlight_destroy(struct drm_device *dev)
+{
+ return;
+}
+#endif
--
1.7.3.2

2010-11-19 15:55:32

by Matthew Garrett

[permalink] [raw]
Subject: [PATCH 3/5] radeon: Expose backlight class device for legacy LVDS encoder

From: Michel Dänzer <[email protected]>

Allows e.g. power management daemons to control the backlight level. Inspired
by the corresponding code in radeonfb.

(Updated to add backlight type and make the connector the parent device - mjg)

Signed-off-by: Michel Dänzer <[email protected]>
Signed-off-by: Matthew Garrett <[email protected]>
Cc: [email protected]
---
drivers/gpu/drm/radeon/Kconfig | 1 +
drivers/gpu/drm/radeon/radeon_connectors.c | 15 ++
drivers/gpu/drm/radeon/radeon_legacy_encoders.c | 257 ++++++++++++++++++++++-
drivers/gpu/drm/radeon/radeon_mode.h | 10 +
4 files changed, 277 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/radeon/Kconfig b/drivers/gpu/drm/radeon/Kconfig
index 1c02d23..9746fee 100644
--- a/drivers/gpu/drm/radeon/Kconfig
+++ b/drivers/gpu/drm/radeon/Kconfig
@@ -1,6 +1,7 @@
config DRM_RADEON_KMS
bool "Enable modesetting on radeon by default - NEW DRIVER"
depends on DRM_RADEON
+ select BACKLIGHT_CLASS_DEVICE
help
Choose this option if you want kernel modesetting enabled by default.

diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index fe6c747..d20bc76 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -40,6 +40,10 @@ radeon_atombios_connected_scratch_regs(struct drm_connector *connector,
struct drm_encoder *encoder,
bool connected);

+extern void
+radeon_legacy_backlight_init(struct radeon_encoder *radeon_encoder,
+ struct drm_connector *drm_connector);
+
void radeon_connector_hotplug(struct drm_connector *connector)
{
struct drm_device *dev = connector->dev;
@@ -1462,6 +1466,17 @@ radeon_add_legacy_connector(struct drm_device *dev,
connector->polled = DRM_CONNECTOR_POLL_HPD;
connector->display_info.subpixel_order = subpixel_order;
drm_sysfs_connector_add(connector);
+ if (connector_type == DRM_MODE_CONNECTOR_LVDS) {
+ struct drm_encoder *drm_encoder;
+
+ list_for_each_entry(drm_encoder, &dev->mode_config.encoder_list, head) {
+ struct radeon_encoder *radeon_encoder;
+
+ radeon_encoder = to_radeon_encoder(drm_encoder);
+ if (radeon_encoder->encoder_id == ENCODER_OBJECT_ID_INTERNAL_LVDS)
+ radeon_legacy_backlight_init(radeon_encoder, connector);
+ }
+ }
return;

failed:
diff --git a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
index 0b83970..bdca317 100644
--- a/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_legacy_encoders.c
@@ -28,6 +28,10 @@
#include "radeon_drm.h"
#include "radeon.h"
#include "atom.h"
+#include <linux/backlight.h>
+#ifdef CONFIG_PMAC_BACKLIGHT
+#include <asm/backlight.h>
+#endif

static void radeon_legacy_encoder_disable(struct drm_encoder *encoder)
{
@@ -39,7 +43,7 @@ static void radeon_legacy_encoder_disable(struct drm_encoder *encoder)
radeon_encoder->active_device = 0;
}

-static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
+static void radeon_legacy_lvds_update(struct drm_encoder *encoder, int mode)
{
struct drm_device *dev = encoder->dev;
struct radeon_device *rdev = dev->dev_private;
@@ -47,15 +51,23 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
uint32_t lvds_gen_cntl, lvds_pll_cntl, pixclks_cntl, disp_pwr_man;
int panel_pwr_delay = 2000;
bool is_mac = false;
+ uint8_t backlight_level;
DRM_DEBUG_KMS("\n");

+ lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
+ backlight_level = (lvds_gen_cntl >> RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
if (radeon_encoder->enc_priv) {
if (rdev->is_atom_bios) {
struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
panel_pwr_delay = lvds->panel_pwr_delay;
+ if (lvds->bl_dev)
+ backlight_level = lvds->backlight_level;
} else {
struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
panel_pwr_delay = lvds->panel_pwr_delay;
+ if (lvds->bl_dev)
+ backlight_level = lvds->backlight_level;
}
}

@@ -82,11 +94,13 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
lvds_pll_cntl &= ~RADEON_LVDS_PLL_RESET;
WREG32(RADEON_LVDS_PLL_CNTL, lvds_pll_cntl);

- lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
- lvds_gen_cntl |= (RADEON_LVDS_ON | RADEON_LVDS_EN | RADEON_LVDS_DIGON | RADEON_LVDS_BLON);
+ lvds_gen_cntl &= ~(RADEON_LVDS_DISPLAY_DIS |
+ RADEON_LVDS_BL_MOD_LEVEL_MASK);
+ lvds_gen_cntl |= (RADEON_LVDS_ON | RADEON_LVDS_EN |
+ RADEON_LVDS_DIGON | RADEON_LVDS_BLON |
+ (backlight_level << RADEON_LVDS_BL_MOD_LEVEL_SHIFT));
if (is_mac)
lvds_gen_cntl |= RADEON_LVDS_BL_MOD_EN;
- lvds_gen_cntl &= ~(RADEON_LVDS_DISPLAY_DIS);
udelay(panel_pwr_delay * 1000);
WREG32(RADEON_LVDS_GEN_CNTL, lvds_gen_cntl);
break;
@@ -95,7 +109,6 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
case DRM_MODE_DPMS_OFF:
pixclks_cntl = RREG32_PLL(RADEON_PIXCLKS_CNTL);
WREG32_PLL_P(RADEON_PIXCLKS_CNTL, 0, ~RADEON_PIXCLK_LVDS_ALWAYS_ONb);
- lvds_gen_cntl = RREG32(RADEON_LVDS_GEN_CNTL);
lvds_gen_cntl |= RADEON_LVDS_DISPLAY_DIS;
if (is_mac) {
lvds_gen_cntl &= ~RADEON_LVDS_BL_MOD_EN;
@@ -119,6 +132,25 @@ static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)

}

+static void radeon_legacy_lvds_dpms(struct drm_encoder *encoder, int mode)
+{
+ struct radeon_device *rdev = encoder->dev->dev_private;
+ struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
+ DRM_DEBUG("\n");
+
+ if (radeon_encoder->enc_priv) {
+ if (rdev->is_atom_bios) {
+ struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+ lvds->dpms_mode = mode;
+ } else {
+ struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+ lvds->dpms_mode = mode;
+ }
+ }
+
+ radeon_legacy_lvds_update(encoder, mode);
+}
+
static void radeon_legacy_lvds_prepare(struct drm_encoder *encoder)
{
struct radeon_device *rdev = encoder->dev->dev_private;
@@ -237,9 +269,222 @@ static const struct drm_encoder_helper_funcs radeon_legacy_lvds_helper_funcs = {
.disable = radeon_legacy_encoder_disable,
};

+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+
+#define MAX_RADEON_LEVEL 0xFF
+
+struct radeon_backlight_privdata {
+ struct radeon_encoder *encoder;
+ uint8_t negative;
+};
+
+static uint8_t radeon_legacy_lvds_level(struct backlight_device *bd)
+{
+ struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+ uint8_t level;
+
+ /* Convert brightness to hardware level */
+ if (bd->props.brightness < 0)
+ level = 0;
+ else if (bd->props.brightness > MAX_RADEON_LEVEL)
+ level = MAX_RADEON_LEVEL;
+ else
+ level = bd->props.brightness;
+
+ if (pdata->negative)
+ level = MAX_RADEON_LEVEL - level;
+
+ return level;
+}
+
+static int radeon_legacy_backlight_update_status(struct backlight_device *bd)
+{
+ struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+ struct radeon_encoder *radeon_encoder = pdata->encoder;
+ struct drm_device *dev = radeon_encoder->base.dev;
+ struct radeon_device *rdev = dev->dev_private;
+ int dpms_mode = DRM_MODE_DPMS_ON;
+
+ if (radeon_encoder->enc_priv) {
+ if (rdev->is_atom_bios) {
+ struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+ dpms_mode = lvds->dpms_mode;
+ lvds->backlight_level = radeon_legacy_lvds_level(bd);
+ } else {
+ struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+ dpms_mode = lvds->dpms_mode;
+ lvds->backlight_level = radeon_legacy_lvds_level(bd);
+ }
+ }
+
+ if (bd->props.brightness > 0)
+ radeon_legacy_lvds_update(&radeon_encoder->base, dpms_mode);
+ else
+ radeon_legacy_lvds_update(&radeon_encoder->base, DRM_MODE_DPMS_OFF);
+
+ return 0;
+}
+
+static int radeon_legacy_backlight_get_brightness(struct backlight_device *bd)
+{
+ struct radeon_backlight_privdata *pdata = bl_get_data(bd);
+ struct radeon_encoder *radeon_encoder = pdata->encoder;
+ struct drm_device *dev = radeon_encoder->base.dev;
+ struct radeon_device *rdev = dev->dev_private;
+ uint8_t backlight_level;
+
+ backlight_level = (RREG32(RADEON_LVDS_GEN_CNTL) >>
+ RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
+ return pdata->negative ? MAX_RADEON_LEVEL - backlight_level : backlight_level;
+}
+
+static const struct backlight_ops radeon_backlight_ops = {
+ .get_brightness = radeon_legacy_backlight_get_brightness,
+ .update_status = radeon_legacy_backlight_update_status,
+};
+
+void radeon_legacy_backlight_init(struct radeon_encoder *radeon_encoder,
+ struct drm_connector *drm_connector)
+{
+ struct drm_device *dev = radeon_encoder->base.dev;
+ struct radeon_device *rdev = dev->dev_private;
+ struct backlight_device *bd;
+ struct backlight_properties props;
+ struct radeon_backlight_privdata *pdata;
+ uint8_t backlight_level;
+
+ if (!radeon_encoder->enc_priv)
+ return;
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+ if (!pmac_has_backlight_type("ati") &&
+ !pmac_has_backlight_type("mnca"))
+ return;
+#endif
+
+ pdata = kmalloc(sizeof(struct radeon_backlight_privdata), GFP_KERNEL);
+ if (!pdata) {
+ DRM_ERROR("Memory allocation failed\n");
+ goto error;
+ }
+
+ props.max_brightness = MAX_RADEON_LEVEL;
+ props.type = BACKLIGHT_RAW;
+ bd = backlight_device_register("radeon_bl", &drm_connector->kdev,
+ pdata, &radeon_backlight_ops, &props);
+ if (IS_ERR(bd)) {
+ DRM_ERROR("Backlight registration failed\n");
+ goto error;
+ }
+
+ pdata->encoder = radeon_encoder;
+
+ backlight_level = (RREG32(RADEON_LVDS_GEN_CNTL) >>
+ RADEON_LVDS_BL_MOD_LEVEL_SHIFT) & 0xff;
+
+ /* First, try to detect backlight level sense based on the assumption
+ * that firmware set it up at full brightness
+ */
+ if (backlight_level == 0)
+ pdata->negative = true;
+ else if (backlight_level == 0xff)
+ pdata->negative = false;
+ else {
+ /* XXX hack... maybe some day we can figure out in what direction
+ * backlight should work on a given panel?
+ */
+ pdata->negative = (rdev->family != CHIP_RV200 &&
+ rdev->family != CHIP_RV250 &&
+ rdev->family != CHIP_RV280 &&
+ rdev->family != CHIP_RV350);
+
+#ifdef CONFIG_PMAC_BACKLIGHT
+ pdata->negative = (pdata->negative ||
+ of_machine_is_compatible("PowerBook4,3") ||
+ of_machine_is_compatible("PowerBook6,3") ||
+ of_machine_is_compatible("PowerBook6,5"));
+#endif
+ }
+
+ if (rdev->is_atom_bios) {
+ struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+ lvds->bl_dev = bd;
+ } else {
+ struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+ lvds->bl_dev = bd;
+ }
+
+ bd->props.brightness = radeon_legacy_backlight_get_brightness(bd);
+ bd->props.power = FB_BLANK_UNBLANK;
+ backlight_update_status(bd);
+
+ DRM_INFO("radeon legacy LVDS backlight initialized\n");
+
+ return;
+
+error:
+ kfree(pdata);
+ return;
+}
+
+static void radeon_legacy_backlight_exit(struct radeon_encoder *radeon_encoder)
+{
+ struct drm_device *dev = radeon_encoder->base.dev;
+ struct radeon_device *rdev = dev->dev_private;
+ struct backlight_device *bd = NULL;
+
+ if (!radeon_encoder->enc_priv)
+ return;
+
+ if (rdev->is_atom_bios) {
+ struct radeon_encoder_atom_dig *lvds = radeon_encoder->enc_priv;
+ bd = lvds->bl_dev;
+ lvds->bl_dev = NULL;
+ } else {
+ struct radeon_encoder_lvds *lvds = radeon_encoder->enc_priv;
+ bd = lvds->bl_dev;
+ lvds->bl_dev = NULL;
+ }
+
+ if (bd) {
+ struct radeon_legacy_backlight_privdata *pdata;
+
+ pdata = bl_get_data(bd);
+ backlight_device_unregister(bd);
+ kfree(pdata);
+
+ DRM_INFO("radeon legacy LVDS backlight unloaded\n");
+ }
+}
+
+#else /* !CONFIG_BACKLIGHT_CLASS_DEVICE */
+
+static void radeon_legacy_backlight_init(struct radeon_encoder *encoder)
+{
+}
+
+static void radeon_legacy_backlight_exit(struct radeon_encoder *encoder)
+{
+}
+
+#endif
+
+
+static void radeon_lvds_enc_destroy(struct drm_encoder *encoder)
+{
+ struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
+
+ if (radeon_encoder->enc_priv) {
+ radeon_legacy_backlight_exit(radeon_encoder);
+ kfree(radeon_encoder->enc_priv);
+ }
+ drm_encoder_cleanup(encoder);
+ kfree(radeon_encoder);
+}

static const struct drm_encoder_funcs radeon_legacy_lvds_enc_funcs = {
- .destroy = radeon_enc_destroy,
+ .destroy = radeon_lvds_enc_destroy,
};

static void radeon_legacy_primary_dac_dpms(struct drm_encoder *encoder, int mode)
diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index 680f576..994f297 100644
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -297,6 +297,11 @@ struct radeon_encoder_lvds {
uint32_t lvds_gen_cntl;
/* panel mode */
struct drm_display_mode native_mode;
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+ struct backlight_device *bl_dev;
+ int dpms_mode;
+ uint8_t backlight_level;
+#endif
};

struct radeon_encoder_tv_dac {
@@ -350,6 +355,11 @@ struct radeon_encoder_atom_dig {
uint32_t lcd_ss_id;
/* panel mode */
struct drm_display_mode native_mode;
+#ifdef CONFIG_BACKLIGHT_CLASS_DEVICE
+ struct backlight_device *bl_dev;
+ int dpms_mode;
+ uint8_t backlight_level;
+#endif
};

struct radeon_encoder_atom_dac {
--
1.7.3.2

2010-11-19 15:55:34

by Matthew Garrett

[permalink] [raw]
Subject: [PATCH 4/5] nouveau: Change the backlight parent device to the connector, not the PCI dev

We may eventually end up with per-connector backlights, especially with
ddcci devices. Make sure that the parent node for the backlight device is
the connector rather than the PCI device.

Signed-off-by: Matthew Garrett <[email protected]>
---
drivers/gpu/drm/nouveau/nouveau_backlight.c | 21 ++++++++++++---------
drivers/gpu/drm/nouveau/nouveau_connector.c | 9 +++++++++
drivers/gpu/drm/nouveau/nouveau_drv.h | 4 ++--
3 files changed, 23 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_backlight.c b/drivers/gpu/drm/nouveau/nouveau_backlight.c
index 9485af3..7e8a448 100644
--- a/drivers/gpu/drm/nouveau/nouveau_backlight.c
+++ b/drivers/gpu/drm/nouveau/nouveau_backlight.c
@@ -87,10 +87,11 @@ static struct backlight_ops nv50_bl_ops = {
.update_status = nv50_set_intensity,
};

-static int nouveau_nv40_backlight_init(struct drm_device *dev)
+static int nouveau_nv40_backlight_init(struct drm_connector *connector)
{
- struct backlight_properties props;
+ struct drm_device *dev = connector->dev;
struct drm_nouveau_private *dev_priv = dev->dev_private;
+ struct backlight_properties props;
struct backlight_device *bd;

if (!(nv_rd32(dev, NV40_PMC_BACKLIGHT) & NV40_PMC_BACKLIGHT_MASK))
@@ -99,7 +100,7 @@ static int nouveau_nv40_backlight_init(struct drm_device *dev)
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = 31;
- bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
+ bd = backlight_device_register("nv_backlight", &connector->kdev, dev,
&nv40_bl_ops, &props);
if (IS_ERR(bd))
return PTR_ERR(bd);
@@ -111,10 +112,11 @@ static int nouveau_nv40_backlight_init(struct drm_device *dev)
return 0;
}

-static int nouveau_nv50_backlight_init(struct drm_device *dev)
+static int nouveau_nv50_backlight_init(struct drm_connector *connector)
{
- struct backlight_properties props;
+ struct drm_device *dev = connector->dev;
struct drm_nouveau_private *dev_priv = dev->dev_private;
+ struct backlight_properties props;
struct backlight_device *bd;

if (!nv_rd32(dev, NV50_PDISPLAY_SOR_BACKLIGHT))
@@ -123,7 +125,7 @@ static int nouveau_nv50_backlight_init(struct drm_device *dev)
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = 1025;
- bd = backlight_device_register("nv_backlight", &dev->pdev->dev, dev,
+ bd = backlight_device_register("nv_backlight", &connector->kdev, dev,
&nv50_bl_ops, &props);
if (IS_ERR(bd))
return PTR_ERR(bd);
@@ -134,15 +136,16 @@ static int nouveau_nv50_backlight_init(struct drm_device *dev)
return 0;
}

-int nouveau_backlight_init(struct drm_device *dev)
+int nouveau_backlight_init(struct drm_connector *connector)
{
+ struct drm_device *dev = connector->dev;
struct drm_nouveau_private *dev_priv = dev->dev_private;

switch (dev_priv->card_type) {
case NV_40:
- return nouveau_nv40_backlight_init(dev);
+ return nouveau_nv40_backlight_init(connector);
case NV_50:
- return nouveau_nv50_backlight_init(dev);
+ return nouveau_nv50_backlight_init(connector);
default:
break;
}
diff --git a/drivers/gpu/drm/nouveau/nouveau_connector.c b/drivers/gpu/drm/nouveau/nouveau_connector.c
index 0871495..914058d 100644
--- a/drivers/gpu/drm/nouveau/nouveau_connector.c
+++ b/drivers/gpu/drm/nouveau/nouveau_connector.c
@@ -106,6 +106,10 @@ nouveau_connector_destroy(struct drm_connector *drm_connector)
dev = nv_connector->base.dev;
NV_DEBUG_KMS(dev, "\n");

+ if (drm_connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
+ drm_connector->connector_type == DRM_MODE_CONNECTOR_eDP)
+ nouveau_backlight_exit(dev);
+
kfree(nv_connector->edid);
drm_sysfs_connector_remove(drm_connector);
drm_connector_cleanup(drm_connector);
@@ -894,6 +898,11 @@ nouveau_connector_create(struct drm_device *dev, int index)
nouveau_connector_set_polling(connector);

drm_sysfs_connector_add(connector);
+
+ if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
+ connector->connector_type == DRM_MODE_CONNECTOR_eDP)
+ nouveau_backlight_init(connector);
+
dcb->drm = connector;
return dcb->drm;

diff --git a/drivers/gpu/drm/nouveau/nouveau_drv.h b/drivers/gpu/drm/nouveau/nouveau_drv.h
index 3a07e58..3c65b77 100644
--- a/drivers/gpu/drm/nouveau/nouveau_drv.h
+++ b/drivers/gpu/drm/nouveau/nouveau_drv.h
@@ -933,10 +933,10 @@ static inline int nouveau_acpi_edid(struct drm_device *dev, struct drm_connector

/* nouveau_backlight.c */
#ifdef CONFIG_DRM_NOUVEAU_BACKLIGHT
-extern int nouveau_backlight_init(struct drm_device *);
+extern int nouveau_backlight_init(struct drm_connector *);
extern void nouveau_backlight_exit(struct drm_device *);
#else
-static inline int nouveau_backlight_init(struct drm_device *dev)
+static inline int nouveau_backlight_init(struct drm_connector *dev)
{
return 0;
}
--
1.7.3.2

2010-11-19 20:07:11

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Fri, 19 Nov 2010 10:53:52 -0500
Matthew Garrett <[email protected]> wrote:

> 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.
>
> ...
>
> 60 files changed, 102 insertions(+), 0 deletions(-)

This patch has a pretty short half-life.

>
> ...
>
> --- a/include/linux/backlight.h
> +++ b/include/linux/backlight.h
> @@ -32,6 +32,12 @@ enum backlight_update_reason {
> BACKLIGHT_UPDATE_SYSFS,
> };
>
> +enum backlight_type {
> + BACKLIGHT_RAW,
> + BACKLIGHT_PLATFORM,
> + BACKLIGHT_FIRMWARE,
> +};
> +
> struct backlight_device;
> struct fb_info;
>
> @@ -62,6 +68,8 @@ struct backlight_properties {
> /* FB Blanking active? (values as for power) */
> /* Due to be removed, please use (state & BL_CORE_FBBLANK) */
> int fb_blank;
> + /* Backlight type */
> + enum backlight_type type;
> /* Flags used to signal drivers of state changes */
> /* Upper 4 bits are reserved for driver internal use */
> unsigned int state;

And if/when the half-life expires, we'll have drivers in-tree which
forget to set backlight_properties.type. I haven't checked, but if
we're lucky they will default to "0".

What will be the runtime effects upon such unconverted drivers?
Ideally we'd like them to continue to work OK, and to emit a runtime
warning. In which case you'll need BACKLIGHT_RAW=1 so the unconverted
driver can be detected, warned about and fixed up by the core code.

2010-11-19 20:26:09

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Fri, Nov 19, 2010 at 12:05:23PM -0800, Andrew Morton wrote:
> On Fri, 19 Nov 2010 10:53:52 -0500
> Matthew Garrett <[email protected]> wrote:
>
> > 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.
> >
> > ...
> >
> > 60 files changed, 102 insertions(+), 0 deletions(-)
>
> This patch has a pretty short half-life.

Well, ideally it would have landed in the backlight tree when I sent it
months ago. Then we'd have the opportunity to ensure that everything was
fixed up before it went in in the merge window.

> > @@ -62,6 +68,8 @@ struct backlight_properties {
> > /* FB Blanking active? (values as for power) */
> > /* Due to be removed, please use (state & BL_CORE_FBBLANK) */
> > int fb_blank;
> > + /* Backlight type */
> > + enum backlight_type type;
> > /* Flags used to signal drivers of state changes */
> > /* Upper 4 bits are reserved for driver internal use */
> > unsigned int state;
>
> And if/when the half-life expires, we'll have drivers in-tree which
> forget to set backlight_properties.type. I haven't checked, but if
> we're lucky they will default to "0".

Depends entirely on whether they kzalloc the structure or not before
calling backlight_device_register().

> What will be the runtime effects upon such unconverted drivers?
> Ideally we'd like them to continue to work OK, and to emit a runtime
> warning. In which case you'll need BACKLIGHT_RAW=1 so the unconverted
> driver can be detected, warned about and fixed up by the core code.

The worst case I can think of is that we walk off the array - I guess
there's an argument for sanity checking that in backlight_show_type().

--
Matthew Garrett | [email protected]

2010-11-19 20:36:06

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Fri, 19 Nov 2010 20:25:59 +0000
Matthew Garrett <[email protected]> wrote:

> On Fri, Nov 19, 2010 at 12:05:23PM -0800, Andrew Morton wrote:
> > On Fri, 19 Nov 2010 10:53:52 -0500
> > Matthew Garrett <[email protected]> wrote:
> >
> > > 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.
> > >
> > > ...
> > >
> > > 60 files changed, 102 insertions(+), 0 deletions(-)
> >
> > This patch has a pretty short half-life.
>
> Well, ideally it would have landed in the backlight tree when I sent it
> months ago. Then we'd have the opportunity to ensure that everything was
> fixed up before it went in in the merge window.

Richard got distracted. At present I'm grabbing the leds and backlight
patches and Richard is reviewing them as they fly past.

I don't see there's much point in me merging this patch series so if it
survives review, I'd suggest that you put it into an mjg tree and
thence into linux-next and mainline?

> > > @@ -62,6 +68,8 @@ struct backlight_properties {
> > > /* FB Blanking active? (values as for power) */
> > > /* Due to be removed, please use (state & BL_CORE_FBBLANK) */
> > > int fb_blank;
> > > + /* Backlight type */
> > > + enum backlight_type type;
> > > /* Flags used to signal drivers of state changes */
> > > /* Upper 4 bits are reserved for driver internal use */
> > > unsigned int state;
> >
> > And if/when the half-life expires, we'll have drivers in-tree which
> > forget to set backlight_properties.type. I haven't checked, but if
> > we're lucky they will default to "0".
>
> Depends entirely on whether they kzalloc the structure or not before
> calling backlight_device_register().

Well. Even if it's uninitialised, the chances of the value being 1, 2
or 3 for all users are pretty small, so we'll still get to hear about
it if the runtime check is appropriately implemented.

> > What will be the runtime effects upon such unconverted drivers?
> > Ideally we'd like them to continue to work OK, and to emit a runtime
> > warning. In which case you'll need BACKLIGHT_RAW=1 so the unconverted
> > driver can be detected, warned about and fixed up by the core code.
>
> The worst case I can think of is that we walk off the array - I guess
> there's an argument for sanity checking that in backlight_show_type().

OK, well please have a think about it, see what you can do to handle
unconverted (and possibly out-of-tree) drivers in a friendly fashion.

2010-11-22 10:20:54

by Richard Purdie

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Fri, 2010-11-19 at 20:25 +0000, Matthew Garrett wrote:
> On Fri, Nov 19, 2010 at 12:05:23PM -0800, Andrew Morton wrote:
> > On Fri, 19 Nov 2010 10:53:52 -0500
> > Matthew Garrett <[email protected]> wrote:
> >
> > > 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.
> > >
> > > ...
> > >
> > > 60 files changed, 102 insertions(+), 0 deletions(-)
> >
> > This patch has a pretty short half-life.
>
> Well, ideally it would have landed in the backlight tree when I sent it
> months ago. Then we'd have the opportunity to ensure that everything was
> fixed up before it went in in the merge window.
>
> > > @@ -62,6 +68,8 @@ struct backlight_properties {
> > > /* FB Blanking active? (values as for power) */
> > > /* Due to be removed, please use (state & BL_CORE_FBBLANK) */
> > > int fb_blank;
> > > + /* Backlight type */
> > > + enum backlight_type type;
> > > /* Flags used to signal drivers of state changes */
> > > /* Upper 4 bits are reserved for driver internal use */
> > > unsigned int state;
> >
> > And if/when the half-life expires, we'll have drivers in-tree which
> > forget to set backlight_properties.type. I haven't checked, but if
> > we're lucky they will default to "0".
>
> Depends entirely on whether they kzalloc the structure or not before
> calling backlight_device_register().
>
> > What will be the runtime effects upon such unconverted drivers?
> > Ideally we'd like them to continue to work OK, and to emit a runtime
> > warning. In which case you'll need BACKLIGHT_RAW=1 so the unconverted
> > driver can be detected, warned about and fixed up by the core code.
>
> The worst case I can think of is that we walk off the array - I guess
> there's an argument for sanity checking that in backlight_show_type().

I think adding a BACKLIGHT_TYPEUNKNOWN as the first item in the enum,
sanity checking the array bounds and printing a warning if type is not
one of the defined values would be good.

I also want to make sure you think this patch is going to scale with
multiple GPU output machines? Thats the main reason I've held off any
patch like this as it doesn't help solve that problem as far as I can
tell. Yes, we have the device parent information and I see later in the
patch series you ensure the backlight is registered against the
connector which is good. If you have an ACPI "firmware" control that you
say should always be preferred, how do we know which connector device
that corresponds to in the multiple output case? From that point of view
this model falls apart?

What I really want to avoid is a new interface which just papers over
cracks, only to have everything crumble anyway.

Cheers,

Richard


2010-11-22 12:31:00

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Mon, Nov 22, 2010 at 10:17:00AM +0000, Richard Purdie wrote:

> I also want to make sure you think this patch is going to scale with
> multiple GPU output machines? Thats the main reason I've held off any
> patch like this as it doesn't help solve that problem as far as I can
> tell. Yes, we have the device parent information and I see later in the
> patch series you ensure the backlight is registered against the
> connector which is good. If you have an ACPI "firmware" control that you
> say should always be preferred, how do we know which connector device
> that corresponds to in the multiple output case? From that point of view
> this model falls apart?

The ACPI device will point at the correct PCI device. Associating it
with the appropriate connector is theoretically possible in the case of
open drivers, but I hadn't seen it as a high priority since (in
practice) there's no situations where an ACPI interface will be able to
control more than one backlight.

--
Matthew Garrett | [email protected]

2010-11-22 13:36:46

by Richard Purdie

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Mon, 2010-11-22 at 12:30 +0000, Matthew Garrett wrote:
> On Mon, Nov 22, 2010 at 10:17:00AM +0000, Richard Purdie wrote:
>
> > I also want to make sure you think this patch is going to scale with
> > multiple GPU output machines? Thats the main reason I've held off any
> > patch like this as it doesn't help solve that problem as far as I can
> > tell. Yes, we have the device parent information and I see later in the
> > patch series you ensure the backlight is registered against the
> > connector which is good. If you have an ACPI "firmware" control that you
> > say should always be preferred, how do we know which connector device
> > that corresponds to in the multiple output case? From that point of view
> > this model falls apart?
>
> The ACPI device will point at the correct PCI device. Associating it
> with the appropriate connector is theoretically possible in the case of
> open drivers, but I hadn't seen it as a high priority since (in
> practice) there's no situations where an ACPI interface will be able to
> control more than one backlight.

Its the reverse situation I worry about. Are there situations where
there are multiple connectors on the PCI device and the ACPI interface
just controls one of them but controls for the other connectors may
exist?

I'm typing this with an external monitor plugged into my laptop with
i915 graphics...

Cheers,

Richard




2010-11-22 13:40:14

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 1/5] Backlight: Add backlight type

On Mon, Nov 22, 2010 at 01:35:48PM +0000, Richard Purdie wrote:

> Its the reverse situation I worry about. Are there situations where
> there are multiple connectors on the PCI device and the ACPI interface
> just controls one of them but controls for the other connectors may
> exist?

Yes, that's certainly possible and it'd be desirable to fix this up, but
the same problem also applies to platform interfaces and it's typically
unfixable there. My userspace implementation looks at the connector type
to determine the best approach - if it's not LVDS or eDP it ignores the
firmware and platform interfaces, so you'll fall back to the raw
interface if it can provide support for your connector (presumably via
ddcci, although we don't have this implemented yet)

--
Matthew Garrett | [email protected]

2011-02-06 20:35:27

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Friday, January 14, 2011, Matthew Garrett wrote:
> Dual-GPU machines may provide more than one ACPI backlight interface. Tie
> the backlight device to the GPU in order to allow userspace to identify
> the correct interface.
>
> Signed-off-by: Matthew Garrett <[email protected]>

Sorry for the late response, but I've just realized there's a problem with this
patch.

> ---
> drivers/acpi/video.c | 15 ++++++++++++++-
> 1 files changed, 14 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
> index a9eec8c..a18e497 100644
> --- a/drivers/acpi/video.c
> +++ b/drivers/acpi/video.c
> @@ -782,6 +782,9 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
>
> if (acpi_video_backlight_support()) {
> struct backlight_properties props;
> + struct pci_dev *pdev;
> + acpi_handle acpi_parent;
> + struct device *parent = NULL;
> int result;
> static int count = 0;
> char *name;
> @@ -794,10 +797,20 @@ static void acpi_video_device_find_cap(struct acpi_video_device *device)
> return;
> count++;
>
> + acpi_get_parent(device->dev->handle, &acpi_parent);
> +
> + pdev = acpi_get_pci_dev(acpi_parent);
> + if (pdev) {
> + parent = &pdev->dev;
> + pci_dev_put(pdev);
> + }

I'm afraid you can't do that or suspend problems will happen.

Namely, the PM core assumes that parents will be registered before their
children and it is a very strong assumption. If violated, it may lead to
a suspend sequence deadlock.

Unfortunately, it looks like the ACPI video device is registered before the
PCI device that's becoming it's parent, so the above assumption will be
violated.

Thanks,
Rafael

2011-02-06 20:56:35

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Sun, Feb 06, 2011 at 09:35:07PM +0100, Rafael J. Wysocki wrote:
> > + acpi_get_parent(device->dev->handle, &acpi_parent);
> > +
> > + pdev = acpi_get_pci_dev(acpi_parent);
> > + if (pdev) {
> > + parent = &pdev->dev;
> > + pci_dev_put(pdev);
> > + }
>
> I'm afraid you can't do that or suspend problems will happen.

Ugh. Ok, how can we fix this?

--
Matthew Garrett | [email protected]

2011-02-06 22:41:42

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Sunday, February 06, 2011, Matthew Garrett wrote:
> On Sun, Feb 06, 2011 at 09:35:07PM +0100, Rafael J. Wysocki wrote:
> > > + acpi_get_parent(device->dev->handle, &acpi_parent);
> > > +
> > > + pdev = acpi_get_pci_dev(acpi_parent);
> > > + if (pdev) {
> > > + parent = &pdev->dev;
> > > + pci_dev_put(pdev);
> > > + }
> >
> > I'm afraid you can't do that or suspend problems will happen.
>
> Ugh. Ok, how can we fix this?

Not nicely, I'm afraid.

One possible way is to use device_pm_move_after() to rearrange the devices in
the PM core's suspend list, but that will happen in the video device being
suspended before the new parent (and resumed after it) -- of course, the only
option is to move the ACPI video device after the new parent.

Thanks,
Rafael

2011-02-06 22:53:17

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Sun, Feb 06, 2011 at 11:41:19PM +0100, Rafael J. Wysocki wrote:
> On Sunday, February 06, 2011, Matthew Garrett wrote:
> > Ugh. Ok, how can we fix this?
>
> Not nicely, I'm afraid.
>
> One possible way is to use device_pm_move_after() to rearrange the devices in
> the PM core's suspend list, but that will happen in the video device being
> suspended before the new parent (and resumed after it) -- of course, the only
> option is to move the ACPI video device after the new parent.

Hang on. Didn't we already have a related issue with the acpi video
device being resumed before the video card, resulting in an SMI that
hung the system? I thought we'd arranged things such that resuming the
ACPI video device wouldn't actually do anything until after the PCI
device had been handled? It seems like the correct thing is definitely
for it to be suspended before and resumed after...

--
Matthew Garrett | [email protected]

2011-02-06 23:01:42

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Sunday, February 06, 2011, Matthew Garrett wrote:
> On Sun, Feb 06, 2011 at 11:41:19PM +0100, Rafael J. Wysocki wrote:
> > On Sunday, February 06, 2011, Matthew Garrett wrote:
> > > Ugh. Ok, how can we fix this?
> >
> > Not nicely, I'm afraid.
> >
> > One possible way is to use device_pm_move_after() to rearrange the devices in
> > the PM core's suspend list, but that will happen in the video device being
> > suspended before the new parent (and resumed after it) -- of course, the only
> > option is to move the ACPI video device after the new parent.
>
> Hang on. Didn't we already have a related issue with the acpi video
> device being resumed before the video card, resulting in an SMI that
> hung the system? I thought we'd arranged things such that resuming the
> ACPI video device wouldn't actually do anything until after the PCI
> device had been handled? It seems like the correct thing is definitely
> for it to be suspended before and resumed after...

Yes, it seems so, but I'm not sure what the short term consequences of that
change will be. Perhaps there will be none. :-)

2011-02-06 23:06:20

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Mon, Feb 07, 2011 at 12:01:25AM +0100, Rafael J. Wysocki wrote:

> Yes, it seems so, but I'm not sure what the short term consequences of that
> change will be. Perhaps there will be none. :-)

Ok, I'll have a play with that. Maybe we should be fixing this up
somehow in the acpi-pci glue code? It seems wrong to have acpi devices
resumed before the PCI device they're associated with.

--
Matthew Garrett | [email protected]

2011-02-06 23:35:04

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Monday, February 07, 2011, Matthew Garrett wrote:
> On Mon, Feb 07, 2011 at 12:01:25AM +0100, Rafael J. Wysocki wrote:
>
> > Yes, it seems so, but I'm not sure what the short term consequences of that
> > change will be. Perhaps there will be none. :-)
>
> Ok, I'll have a play with that. Maybe we should be fixing this up
> somehow in the acpi-pci glue code? It seems wrong to have acpi devices
> resumed before the PCI device they're associated with.

Those device's don't have ACPI drivers and therefore they are not really
suspended or resumed, so we don't need to fix anything in that area.

Still, IMO, there is a design issue in the entire ACPI subsystem, because the
idea of "ACPI device" really is not well defined, so to speak. Sometimes
they are just "device interfaces" that can be used to ask the firmware for
something (like in the case of the "ACPI devices" associated with PCI devices)
and sometimes they are "real devices" with real drivers. The video device
apparently wants to be both at the same time, which is even more confusing. :-)

I _think_ that struct acpi_device shouldn't really contain the embedded device
object and each of struct acpi_device objects should be pointed to by the
archdata member of certain struct device. In turn, struct acpi_device should
contain a pointer to the struct device that it's pointed to by via the archdata
field. Then, the struct acpi_device objects will always be "device interfaces"
and all of the device-driver interactions will be represented through their
corresponding device objects. That should allow us to avoid all of the
suspend-resume complications (and all sorts of other ugliness).

2011-02-07 21:32:41

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Sunday, February 06, 2011 04:34:43 pm Rafael J. Wysocki wrote:
>
> Still, IMO, there is a design issue in the entire ACPI subsystem, because the
> idea of "ACPI device" really is not well defined, so to speak. Sometimes
> they are just "device interfaces" that can be used to ask the firmware for
> something (like in the case of the "ACPI devices" associated with PCI devices)
> and sometimes they are "real devices" with real drivers. The video device
> apparently wants to be both at the same time, which is even more confusing. :-)

I'm not familiar with video devices, but I agree, this situation does
feel broken. Is it the case that there's a PCI device as well as an
ACPI namespace Device for the same piece of hardware? If so, I assume
the reason for the ACPI Device is to have a "standard" interface to
a platform knob like backlight control.

In that case, it seems like we should rely on PCI for enumeration and
driver binding, have some sort of hook the PCI driver could use to
twiddle that knob (using the ACPI methods), and make the ACPI Device
ineligible for driver binding. In other words, it sounds like part
of the problem is that we have two drivers binding to what's really
a single piece of hardware.

Bjorn

2011-02-07 21:35:09

by Matthew Garrett

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Mon, Feb 07, 2011 at 02:32:35PM -0700, Bjorn Helgaas wrote:

> I'm not familiar with video devices, but I agree, this situation does
> feel broken. Is it the case that there's a PCI device as well as an
> ACPI namespace Device for the same piece of hardware? If so, I assume
> the reason for the ACPI Device is to have a "standard" interface to
> a platform knob like backlight control.
>
> In that case, it seems like we should rely on PCI for enumeration and
> driver binding, have some sort of hook the PCI driver could use to
> twiddle that knob (using the ACPI methods), and make the ACPI Device
> ineligible for driver binding. In other words, it sounds like part
> of the problem is that we have two drivers binding to what's really
> a single piece of hardware.

Part of the problem is that ACPI video devices aren't inherently PCI
devices.

--
Matthew Garrett | [email protected]

2011-02-07 22:05:06

by Rafael J. Wysocki

[permalink] [raw]
Subject: Re: [PATCH 5/5] ACPI: Tie ACPI backlight devices to PCI devices if possible

On Monday, February 07, 2011, Matthew Garrett wrote:
> On Mon, Feb 07, 2011 at 02:32:35PM -0700, Bjorn Helgaas wrote:
>
> > I'm not familiar with video devices, but I agree, this situation does
> > feel broken. Is it the case that there's a PCI device as well as an
> > ACPI namespace Device for the same piece of hardware? If so, I assume
> > the reason for the ACPI Device is to have a "standard" interface to
> > a platform knob like backlight control.
> >
> > In that case, it seems like we should rely on PCI for enumeration and
> > driver binding, have some sort of hook the PCI driver could use to
> > twiddle that knob (using the ACPI methods), and make the ACPI Device
> > ineligible for driver binding. In other words, it sounds like part
> > of the problem is that we have two drivers binding to what's really
> > a single piece of hardware.
>
> Part of the problem is that ACPI video devices aren't inherently PCI
> devices.

To me, this really isn't about video devices. The problem is that objects
of type struct acpi_device are treated _differently_ depending on the context.

In the meantime I've reviewed the code a bit and noticed that there's a
parent pointer in struct acpi_device, which basically duplicates the device
tree dependency, so it looks like the embedded dev in struct acpi_device is
really redundant.