xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Merge tag 'drm-dp-quirk-for-v4.12-rc4' of git://people.freedesktop.org/~airlied/linux

Browse Source 
Pull drm displayport quirk support:
 "DP quirk for usb c dongles.

  As mentioned I have a separate request for fixing a regression, but
  also keeping the broken hw working, for certain USB-C DP adapters they
  require a minimised n/m parameters, but an attempt to do this
  generically has failed, we need to quirk these specific adapters.
  However doing it generically regressed some eDP panels.

  This pull adds the infrastructure and a quirk for the adapter"

* tag 'drm-dp-quirk-for-v4.12-rc4' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Detect USB-C specific dongles before reducing M and N
  drm/dp: start a DPCD based DP sink/branch device quirk database
  drm/i915: use drm DP helper to read DPCD desc
  drm/dp: add helper for reading DP sink/branch device desc from DPCD
This commit is contained in:
Linus Torvalds
2017-06-02 11:32:38 -07:00
parent c531577bcd 28904eeced
commit 46356945fc
8 changed files with 166 additions and 58 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
include/drm/drm_dp_helper.h
View File

@@ -913,4 +913,55 @@ void drm_dp_aux_unregister(struct drm_dp_aux *aux);
int drm_dp_start_crc(struct drm_dp_aux *aux, struct drm_crtc *crtc);
int drm_dp_stop_crc(struct drm_dp_aux *aux);
struct drm_dp_dpcd_ident {
u8 oui[3];
u8 device_id[6];
u8 hw_rev;
u8 sw_major_rev;
u8 sw_minor_rev;
} __packed;
/**
* struct drm_dp_desc - DP branch/sink device descriptor
* @ident: DP device identification from DPCD 0x400 (sink) or 0x500 (branch).
* @quirks: Quirks; use drm_dp_has_quirk() to query for the quirks.
*/
struct drm_dp_desc {
struct drm_dp_dpcd_ident ident;
u32 quirks;
};
int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc,
bool is_branch);
/**
* enum drm_dp_quirk - Display Port sink/branch device specific quirks
*
* Display Port sink and branch devices in the wild have a variety of bugs, try
* to collect them here. The quirks are shared, but it's up to the drivers to
* implement workarounds for them.
*/
enum drm_dp_quirk {
/**
* @DP_DPCD_QUIRK_LIMITED_M_N:
*
* The device requires main link attributes Mvid and Nvid to be limited
* to 16 bits.
*/
DP_DPCD_QUIRK_LIMITED_M_N,
};
/**
* drm_dp_has_quirk() - does the DP device have a specific quirk
* @desc: Device decriptor filled by drm_dp_read_desc()
* @quirk: Quirk to query for
*
* Return true if DP device identified by @desc has @quirk.
*/
static inline bool
drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk)
{
return desc->quirks & BIT(quirk);
}
#endif /* _DRM_DP_HELPER_H_ */