On Thu, 2009-01-08 at 10:58 +0800, Zhang, Rui wrote: > From: Zhang Rui <rui.zhang@xxxxxxxxx> > Subject: disable the ACPI backlight control on laptops with buggy _BCL methods > > Some users used to control the backlight via the platform interface. > But commit c3d6de698c84efdbdd3781b7058bcc339ab43da8 disables the platform > backlight control if ACPI video backlight control is available. > > This breaks the laptops with buggy _BCL/_BCM/_BQC methods. i.e. only ACPI > backlight I/F are available on these laptops but they don't work. > > With this patch applied, the ACPI backlight control are disabled instead > on these laptops. > > http://bugzilla.kernel.org/show_bug.cgi?id=12037 > http://bugzilla.kernel.org/show_bug.cgi?id=12235 > http://bugzilla.kernel.org/show_bug.cgi?id=12249 > http://bugzilla.kernel.org/show_bug.cgi?id=12302 > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/311716 > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/301524 > > CC: Thomas Renninger <trenn@xxxxxxx> > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> tested-by: Andy Whitcroft <apw@xxxxxxxxxxxxx> > --- > drivers/acpi/video_detect.c | 83 ++++++++++++++++++++++++++++++++++++++++---- > 1 file changed, 77 insertions(+), 6 deletions(-) > > Index: linux-2.6/drivers/acpi/video_detect.c > =================================================================== > --- linux-2.6.orig/drivers/acpi/video_detect.c > +++ linux-2.6/drivers/acpi/video_detect.c > @@ -44,17 +44,88 @@ static long acpi_video_support; > static bool acpi_video_caps_checked; > > static acpi_status > +acpi_backlight_validate_bcl(acpi_handle handle) > +{ > + union acpi_object *obj, *obj2; > + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; > + int level_ac = 0, level_battery = 0; > + int i, count; > + int *levels; > + acpi_status status; > + > + > + status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer); > + if (!ACPI_SUCCESS(status)) > + return status; > + obj = (union acpi_object *)buffer.pointer; > + if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) { > + printk(KERN_ERR PREFIX "Invalid _BCL data\n"); > + status = AE_BAD_DATA; > + goto out; > + } > + > + if (obj->package.count < 2) { > + status = AE_BAD_DATA; > + goto out; > + } > + > + levels = kzalloc(obj->package.count * sizeof(*levels), GFP_KERNEL); > + if (!levels) { > + status = AE_NO_MEMORY; > + goto out; > + } > + > + for (i = 0, count = 0; i < obj->package.count; i++) { > + obj2 = (union acpi_object *)&obj->package.elements[i]; > + if (obj2->type != ACPI_TYPE_INTEGER) { > + printk(KERN_ERR PREFIX "Invalid data\n"); > + continue; > + } > + levels[i] = (u32) obj2->integer.value; > + count ++; > + } > + > + if (count < 2) { > + status = AE_BAD_DATA; > + goto out_free_levels; > + } > + > + for (i = 2, level_ac = levels[0], level_battery = levels[1]; i < count; i ++) { > + if (levels[0] == levels[i]) > + level_ac = 1; > + if (levels[1] == levels[i]) > + level_battery = 1; > + } > + > + if (!level_ac || !level_battery) { > + printk(KERN_ERR PREFIX "Invalid _BCL package\n"); > + status = AE_BAD_DATA; > + goto out_free_levels; > + } > + > + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "found %d brightness levels\n", count)); > + > +out_free_levels: > + kfree(levels); > +out: > + kfree(obj); > + return status; > +} > + > +static acpi_status > acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context, > void **retyurn_value) > { > long *cap = context; > - acpi_handle h_dummy; > + acpi_handle h_dummy1, h_dummy2; > > - if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) && > - ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) { > - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight " > - "support\n")); > - *cap |= ACPI_VIDEO_BACKLIGHT; > + if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy1)) && > + ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy2))) { > + if (ACPI_SUCCESS(acpi_backlight_validate_bcl(h_dummy2))) { > + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight " > + "support\n")); > + *cap |= ACPI_VIDEO_BACKLIGHT; > + } > /* We have backlight support, no need to scan further */ > return AE_CTRL_TERMINATE; > } > > email message attachment > > -------- Forwarded Message -------- > > From: Zhang, Rui <rui.zhang@xxxxxxxxx> > > Subject: don't use buggy _BCL/_BCM/_BQC for backlight control > > Date: Thu, 8 Jan 2009 10:56:50 +0800 > > > > Some users used to control the backlight via the platform interface. > > But commit c3d6de698c84efdbdd3781b7058bcc339ab43da8 disables the platform > > backlight control if ACPI video backlight control is available. > > > > This breaks the laptops with buggy _BCL/_BCM/_BQC methods. i.e. only ACPI > > backlight I/F are available on these laptops but they don't work. > > > > With this patch applied, the ACPI backlight control are disabled instead > > on these laptops. > > > > http://bugzilla.kernel.org/show_bug.cgi?id=12037 > > http://bugzilla.kernel.org/show_bug.cgi?id=12235 > > http://bugzilla.kernel.org/show_bug.cgi?id=12249 > > http://bugzilla.kernel.org/show_bug.cgi?id=12302 > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/311716 > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/301524 > > > > CC: Thomas Renninger <trenn@xxxxxxx> > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > > --- > > drivers/acpi/video_detect.c | 83 ++++++++++++++++++++++++++++++++++++++++---- > > 1 file changed, 77 insertions(+), 6 deletions(-) > > > > Index: linux-2.6/drivers/acpi/video_detect.c > > =================================================================== > > --- linux-2.6.orig/drivers/acpi/video_detect.c > > +++ linux-2.6/drivers/acpi/video_detect.c > > @@ -44,17 +44,88 @@ static long acpi_video_support; > > static bool acpi_video_caps_checked; > > > > static acpi_status > > +acpi_backlight_validate_bcl(acpi_handle handle) > > +{ > > + union acpi_object *obj, *obj2; > > + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; > > + int level_ac = 0, level_battery = 0; > > + int i, count; > > + int *levels; > > + acpi_status status; > > + > > + > > + status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer); > > + if (!ACPI_SUCCESS(status)) > > + return status; > > + obj = (union acpi_object *)buffer.pointer; > > + if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) { > > + printk(KERN_ERR PREFIX "Invalid _BCL data\n"); > > + status = AE_BAD_DATA; > > + goto out; > > + } > > + > > + if (obj->package.count < 2) { > > + status = AE_BAD_DATA; > > + goto out; > > + } > > + > > + levels = kzalloc(obj->package.count * sizeof(*levels), GFP_KERNEL); > > + if (!levels) { > > + status = AE_NO_MEMORY; > > + goto out; > > + } > > + > > + for (i = 0, count = 0; i < obj->package.count; i++) { > > + obj2 = (union acpi_object *)&obj->package.elements[i]; > > + if (obj2->type != ACPI_TYPE_INTEGER) { > > + printk(KERN_ERR PREFIX "Invalid data\n"); > > + continue; > > + } > > + levels[i] = (u32) obj2->integer.value; > > + count ++; > > + } > > + > > + if (count < 2) { > > + status = AE_BAD_DATA; > > + goto out_free_levels; > > + } > > + > > + for (i = 2, level_ac = levels[0], level_battery = levels[1]; i < count; i ++) { > > + if (levels[0] == levels[i]) > > + level_ac = 1; > > + if (levels[1] == levels[i]) > > + level_battery = 1; > > + } > > + > > + if (!level_ac || !level_battery) { > > + printk(KERN_ERR PREFIX "Invalid _BCL package\n"); > > + status = AE_BAD_DATA; > > + goto out_free_levels; > > + } > > + > > + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "found %d brightness levels\n", count)); > > + > > +out_free_levels: > > + kfree(levels); > > +out: > > + kfree(obj); > > + return status; > > +} > > + > > +static acpi_status > > acpi_backlight_cap_match(acpi_handle handle, u32 level, void *context, > > void **retyurn_value) > > { > > long *cap = context; > > - acpi_handle h_dummy; > > + acpi_handle h_dummy1, h_dummy2; > > > > - if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy)) && > > - ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy))) { > > - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight " > > - "support\n")); > > - *cap |= ACPI_VIDEO_BACKLIGHT; > > + if (ACPI_SUCCESS(acpi_get_handle(handle, "_BCM", &h_dummy1)) && > > + ACPI_SUCCESS(acpi_get_handle(handle, "_BCL", &h_dummy2))) { > > + if (ACPI_SUCCESS(acpi_backlight_validate_bcl(h_dummy2))) { > > + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found generic backlight " > > + "support\n")); > > + *cap |= ACPI_VIDEO_BACKLIGHT; > > + } > > /* We have backlight support, no need to scan further */ > > return AE_CTRL_TERMINATE; > > } -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
