diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2016-05-18 11:57:29 +0300 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2016-08-03 07:06:28 +1000 |
| commit | 6608804b3d7f0552a38641b03a4e3aa1852df15b (patch) | |
| tree | 4baee53c0298921f701a4969d49cea587b9a0da1 /drivers/gpu | |
| parent | 44cee85a8824464e7e951e590243c2a85d79c494 (diff) | |
| download | linux-6608804b3d7f0552a38641b03a4e3aa1852df15b.tar.bz2 | |
drm/dp: Add drm_dp_psr_setup_time()
Add a small helper to parse the PSR setup time from the DPCD PSR
capabilities and return the value in microseconds.
v2: Don't waste so many bytes on the psr_setup_time_us[] table
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 8f11b8741e42..eae5ef963cb7 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -860,3 +860,35 @@ void drm_dp_aux_unregister(struct drm_dp_aux *aux) i2c_del_adapter(&aux->ddc); } EXPORT_SYMBOL(drm_dp_aux_unregister); + +#define PSR_SETUP_TIME(x) [DP_PSR_SETUP_TIME_ ## x >> DP_PSR_SETUP_TIME_SHIFT] = (x) + +/** + * drm_dp_psr_setup_time() - PSR setup in time usec + * @psr_cap: PSR capabilities from DPCD + * + * Returns: + * PSR setup time for the panel in microseconds, negative + * error code on failure. + */ +int drm_dp_psr_setup_time(const u8 psr_cap[EDP_PSR_RECEIVER_CAP_SIZE]) +{ + static const u16 psr_setup_time_us[] = { + PSR_SETUP_TIME(330), + PSR_SETUP_TIME(275), + PSR_SETUP_TIME(165), + PSR_SETUP_TIME(110), + PSR_SETUP_TIME(55), + PSR_SETUP_TIME(0), + }; + int i; + + i = (psr_cap[1] & DP_PSR_SETUP_TIME_MASK) >> DP_PSR_SETUP_TIME_SHIFT; + if (i >= ARRAY_SIZE(psr_setup_time_us)) + return -EINVAL; + + return psr_setup_time_us[i]; +} +EXPORT_SYMBOL(drm_dp_psr_setup_time); + +#undef PSR_SETUP_TIME |