releases/3.4.57/drm-i915-quirk-no-pch_pwm_enable-for-dell-xps13-backlight.patch

   1 From e85843bec6c2ea7c10ec61238396891cc2b753a9 Mon Sep 17 00:00:00 2001
   2 From: Kamal Mostafa <kamal@canonical.com>
   3 Date: Fri, 19 Jul 2013 15:02:01 -0700
   4 Subject: drm/i915: quirk no PCH_PWM_ENABLE for Dell XPS13 backlight
   5
   6 From: Kamal Mostafa <kamal@canonical.com>
   7
   8 commit e85843bec6c2ea7c10ec61238396891cc2b753a9 upstream.
   9
  10 BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=47941
  11 BugLink: https://bugs.launchpad.net/bugs/1163720
  12 BugLink: https://bugs.launchpad.net/bugs/1162026
  13
  14 Some machines suffer from non-functional backlight controls if
  15 BLM_PCH_PWM_ENABLE is set, so provide a quirk to avoid doing so.
  16 Apply this quirk to Dell XPS 13 models.
  17
  18 [ kamal: backport to 3.4 ]
  19
  20 Tested-by: Eric Griffith <EGriffith92@gmail.com>
  21 Tested-by: Kent Baxley <kent.baxley@canonical.com>
  22 Signed-off-by: Kamal Mostafa <kamal@canonical.com>
  23 Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
  24 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  25
  26 ---
  27  drivers/gpu/drm/i915/i915_drv.h      |    1 +
  28  drivers/gpu/drm/i915/intel_display.c |   16 ++++++++++++++++
  29  drivers/gpu/drm/i915/intel_lvds.c    |    3 ++-
  30  3 files changed, 19 insertions(+), 1 deletion(-)
  31
  32 --- a/drivers/gpu/drm/i915/i915_drv.h
  33 +++ b/drivers/gpu/drm/i915/i915_drv.h
  34 @@ -296,6 +296,7 @@ enum intel_pch {
  35
  36  #define QUIRK_PIPEA_FORCE (1<<0)
  37  #define QUIRK_LVDS_SSC_DISABLE (1<<1)
  38 +#define QUIRK_NO_PCH_PWM_ENABLE (1<<2)
  39
  40  struct intel_fbdev;
  41  struct intel_fbc_work;
  42 --- a/drivers/gpu/drm/i915/intel_display.c
  43 +++ b/drivers/gpu/drm/i915/intel_display.c
  44 @@ -9160,6 +9160,17 @@ static void quirk_ssc_force_disable(stru
  45         dev_priv->quirks |= QUIRK_LVDS_SSC_DISABLE;
  46  }
  47
  48 +/*
  49 + * Some machines (Dell XPS13) suffer broken backlight controls if
  50 + * BLM_PCH_PWM_ENABLE is set.
  51 + */
  52 +static void quirk_no_pcm_pwm_enable(struct drm_device *dev)
  53 +{
  54 +       struct drm_i915_private *dev_priv = dev->dev_private;
  55 +       dev_priv->quirks |= QUIRK_NO_PCH_PWM_ENABLE;
  56 +       DRM_INFO("applying no-PCH_PWM_ENABLE quirk\n");
  57 +}
  58 +
  59  struct intel_quirk {
  60         int device;
  61         int subsystem_vendor;
  62 @@ -9192,6 +9203,11 @@ struct intel_quirk intel_quirks[] = {
  63
  64         /* Sony Vaio Y cannot use SSC on LVDS */
  65         { 0x0046, 0x104d, 0x9076, quirk_ssc_force_disable },
  66 +
  67 +       /* Dell XPS13 HD Sandy Bridge */
  68 +       { 0x0116, 0x1028, 0x052e, quirk_no_pcm_pwm_enable },
  69 +       /* Dell XPS13 HD and XPS13 FHD Ivy Bridge */
  70 +       { 0x0166, 0x1028, 0x058b, quirk_no_pcm_pwm_enable },
  71  };
  72
  73  static void intel_init_quirks(struct drm_device *dev)
  74 --- a/drivers/gpu/drm/i915/intel_lvds.c
  75 +++ b/drivers/gpu/drm/i915/intel_lvds.c
  76 @@ -1097,7 +1097,8 @@ bool intel_lvds_init(struct drm_device *
  77                 goto failed;
  78
  79  out:
  80 -       if (HAS_PCH_SPLIT(dev)) {
  81 +       if (HAS_PCH_SPLIT(dev) &&
  82 +           !(dev_priv->quirks & QUIRK_NO_PCH_PWM_ENABLE)) {
  83                 u32 pwm;
  84
  85                 pipe = (I915_READ(PCH_LVDS) & LVDS_PIPEB_SELECT) ? 1 : 0;