From f838eb5bd257e8a666aa8c451058fa198df7e299 Mon Sep 17 00:00:00 2001 From: Corentin Chary Date: Wed, 13 Jun 2012 09:32:01 +0200 Subject: acpi: add a way to promote/demote vendor backlight drivers Instead of adding a big blacklist in video_detect.c to set ACPI_VIDEO_BACKLIGHT_DMI_VENDOR correctly, let external modules promote or demote themselves when they know the generic video module won't work. Currently drivers where using acpi_video_unregister() directly but: - That didn't respect any acpi_backlight=[video|vendor] parameter provided by the user. - Any later call to acpi_video_register() would still re-load the generic video module (and some gpu drivers are doing that). This patch fix those two issues. Signed-off-by: Corentin Chary Signed-off-by: Matthew Garrett --- drivers/acpi/video_detect.c | 31 +++++++++++++++++++++++++++++-- 1 file changed, 29 insertions(+), 2 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 45d8097ef4cf..942fa2a998f7 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -182,8 +182,7 @@ long acpi_video_get_capabilities(acpi_handle graphics_handle) } EXPORT_SYMBOL(acpi_video_get_capabilities); -/* Returns true if video.ko can do backlight switching */ -int acpi_video_backlight_support(void) +static void acpi_video_caps_check(void) { /* * We must check whether the ACPI graphics device is physically plugged @@ -191,6 +190,34 @@ int acpi_video_backlight_support(void) */ if (!acpi_video_caps_checked) acpi_video_get_capabilities(NULL); +} + +/* Promote the vendor interface instead of the generic video module. + * This function allow DMI blacklists to be implemented by externals + * platform drivers instead of putting a big blacklist in video_detect.c + * After calling this function you will probably want to call + * acpi_video_unregister() to make sure the video module is not loaded + */ +void acpi_video_dmi_promote_vendor(void) +{ + acpi_video_caps_check(); + acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; +} +EXPORT_SYMBOL(acpi_video_dmi_promote_vendor); + +/* To be called when a driver who previously promoted the vendor + * interface */ +void acpi_video_dmi_demote_vendor(void) +{ + acpi_video_caps_check(); + acpi_video_support &= ~ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; +} +EXPORT_SYMBOL(acpi_video_dmi_demote_vendor); + +/* Returns true if video.ko can do backlight switching */ +int acpi_video_backlight_support(void) +{ + acpi_video_caps_check(); /* First check for boot param -> highest prio */ if (acpi_video_support & ACPI_VIDEO_BACKLIGHT_FORCE_VENDOR) -- cgit v1.2.3 From 084940d5b101e9ca91a689eb5048151b14076839 Mon Sep 17 00:00:00 2001 From: Corentin Chary Date: Wed, 13 Jun 2012 09:32:04 +0200 Subject: acpi/video_detect: blacklist samsung x360 On Samsung X360, the BIOS will set a flag (VDRV) if the generic ACPI backlight device is used. This flag will definitively break the backlight interface (even the vendor interface) untill next reboot. It's why we should prevent video.ko from being used here and we can't rely on a later call to acpi_video_unregister(). Signed-off-by: Corentin Chary Signed-off-by: Matthew Garrett --- drivers/acpi/video_detect.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'drivers/acpi') diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 942fa2a998f7..b728880ef10e 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -132,6 +132,33 @@ find_video(acpi_handle handle, u32 lvl, void *context, void **rv) return AE_OK; } +/* Force to use vendor driver when the ACPI device is known to be + * buggy */ +static int video_detect_force_vendor(const struct dmi_system_id *d) +{ + acpi_video_support |= ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; + return 0; +} + +static struct dmi_system_id video_detect_dmi_table[] = { + /* On Samsung X360, the BIOS will set a flag (VDRV) if generic + * ACPI backlight device is used. This flag will definitively break + * the backlight interface (even the vendor interface) untill next + * reboot. It's why we should prevent video.ko from being used here + * and we can't rely on a later call to acpi_video_unregister(). + */ + { + .callback = video_detect_force_vendor, + .ident = "X360", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), + DMI_MATCH(DMI_PRODUCT_NAME, "X360"), + DMI_MATCH(DMI_BOARD_NAME, "X360"), + }, + }, + { }, +}; + /* * Returns the video capabilities of a specific ACPI graphics device * @@ -164,6 +191,8 @@ long acpi_video_get_capabilities(acpi_handle graphics_handle) * ACPI_VIDEO_BACKLIGHT_DMI_VENDOR; *} */ + + dmi_check_system(video_detect_dmi_table); } else { status = acpi_bus_get_device(graphics_handle, &tmp_dev); if (ACPI_FAILURE(status)) { -- cgit v1.2.3