| Message ID | 1439392001-29637-6-git-send-email-thierry.reding@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, 12 Aug 2015, Thierry Reding <thierry.reding@gmail.com> wrote: > From: Thierry Reding <treding@nvidia.com> > > If the sink support eDP, read the eDP revision from it's DPCD. > > Signed-off-by: Thierry Reding <treding@nvidia.com> > --- > drivers/gpu/drm/drm_dp_helper.c | 30 +++++++++++++++++++++++++++++- > include/drm/drm_dp_helper.h | 1 + > 2 files changed, 30 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c > index 1fe181525604..c711b690508b 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -295,7 +295,7 @@ EXPORT_SYMBOL(drm_dp_dpcd_read_link_status); > */ > int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link) > { > - u8 values[7]; > + u8 values[16], value; > int err; > > memset(link, 0, sizeof(*link)); > @@ -323,6 +323,34 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link) > if (values[6] & DP_SET_ANSI_8B10B) > link->capabilities |= DP_LINK_CAP_ANSI_8B10B; > > + if (values[13] & DP_ALTERNATE_SCRAMBLER_RESET_CAP) { That's not indicative of eDP, that's indicative of edp && alternate scrambler support. DPCD_DISPLAY_CONTROL_CAPABLE bit is a better match: "To allow Source devices to easily identify panels that use DPCD Addresses 00700h through 007FFh, the DPCD_DISPLAY_CONTROL_CAPABLE bit in the eDP_CONFIGURATION_CAP register (DPCD Address 0000Dh, bit 3) has been assigned (eDP v1.2 (and higher)) to indicate this capability, as described in Table 3-3." Also, I'd really appreciate using the macros for DPCD offsets. I do not remember these offsets by heart, and we've defined the macros according to the spec so it would be faster to look things up there. > + err = drm_dp_dpcd_readb(aux, DP_EDP_DPCD_REV, &value); > + if (err < 0) > + return err; > + > + switch (value) { > + case DP_EDP_11: > + link->edp = 0x11; I'm really not sure if this is a good idea, since DP_EDP_11 == 0. Essentially you're promoting to use the magic values for the version checking in code. Sure, we've done that with the DPCD version, but now link->revision is directly from DPCD, and this would not be. BR, Jani. > + break; > + > + case DP_EDP_12: > + link->edp = 0x12; > + break; > + > + case DP_EDP_13: > + link->edp = 0x13; > + break; > + > + case DP_EDP_14: > + link->edp = 0x14; > + break; > + > + default: > + DRM_ERROR("unsupported eDP version: %02x\n", value); > + break; > + } > + } > + > return 0; > } > EXPORT_SYMBOL(drm_dp_link_probe); > diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h > index 9e70ea8b907d..f9e7f484a225 100644 > --- a/include/drm/drm_dp_helper.h > +++ b/include/drm/drm_dp_helper.h > @@ -749,6 +749,7 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, > > struct drm_dp_link { > unsigned char revision; > + unsigned char edp; > unsigned int rate; > unsigned int num_lanes; > unsigned long capabilities; > -- > 2.4.5 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 1fe181525604..c711b690508b 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -295,7 +295,7 @@ EXPORT_SYMBOL(drm_dp_dpcd_read_link_status); */ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link) { - u8 values[7]; + u8 values[16], value; int err; memset(link, 0, sizeof(*link)); @@ -323,6 +323,34 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link) if (values[6] & DP_SET_ANSI_8B10B) link->capabilities |= DP_LINK_CAP_ANSI_8B10B; + if (values[13] & DP_ALTERNATE_SCRAMBLER_RESET_CAP) { + err = drm_dp_dpcd_readb(aux, DP_EDP_DPCD_REV, &value); + if (err < 0) + return err; + + switch (value) { + case DP_EDP_11: + link->edp = 0x11; + break; + + case DP_EDP_12: + link->edp = 0x12; + break; + + case DP_EDP_13: + link->edp = 0x13; + break; + + case DP_EDP_14: + link->edp = 0x14; + break; + + default: + DRM_ERROR("unsupported eDP version: %02x\n", value); + break; + } + } + return 0; } EXPORT_SYMBOL(drm_dp_link_probe); diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 9e70ea8b907d..f9e7f484a225 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -749,6 +749,7 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, struct drm_dp_link { unsigned char revision; + unsigned char edp; unsigned int rate; unsigned int num_lanes; unsigned long capabilities;