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| author |   Ville Syrjälä <ville.syrjala@linux.intel.com> | 2015-08-26 22:55:05 +0300 |
|---|---|---|
| committer |   Jani Nikula <jani.nikula@intel.com> | 2015-09-02 15:49:20 +0300 |
| commit | 79a2b161c12a1b751f53a7698494cb722530bca5 (patch) | |
| tree | 51475dc0effbcef25ba32d681de55e87eff8a3e1 /drivers/gpu/drm/drm_dp_helper.c | |
| parent | drm/atomic: Fix bookkeeping with TEST_ONLY, v3. (diff) | |
| download | linux-dev-79a2b161c12a1b751f53a7698494cb722530bca5.tar.xz linux-dev-79a2b161c12a1b751f53a7698494cb722530bca5.zip | |
drm/dp: Define AUX_RETRY_INTERVAL as 500 us
Currently we react to native and i2c defers by waiting either 400-500 us
or 500-600 us, depending on which code path we take. Consolidate them
all to one define AUX_RETRY_INTERVAL which defines the minimum interval.
Since we've been using two different intervals pick the longer of them
and define AUX_RETRY_INTERVAL as 500 us. For the maximum just use
AUX_RETRY_INTERVAL+100 us.
I want to have a define for this so that I can use it when calculating
the estimated duration of i2c-over-aux transfers. Without a define it
would be very easy to change the sleep duration and neglect to update
the i2c-over-aux estimates.
Cc: Simon Farnsworth <simon.farnsworth@onelan.com>
Cc: moosotc@gmail.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Diffstat (limited to 'drivers/gpu/drm/drm_dp_helper.c')
| -rw-r--r-- | drivers/gpu/drm/drm_dp_helper.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 80a02a412607..7069e54e5b43 100644 --- a/drivers/gpu/drm/drm_dp_helper.c +++ b/drivers/gpu/drm/drm_dp_helper.c @@ -159,6 +159,8 @@ int drm_dp_bw_code_to_link_rate(u8 link_bw) } EXPORT_SYMBOL(drm_dp_bw_code_to_link_rate); +#define AUX_RETRY_INTERVAL 500 /* us */ + /** * DOC: dp helpers * @@ -213,7 +215,7 @@ static int drm_dp_dpcd_access(struct drm_dp_aux *aux, u8 request, return -EIO; case DP_AUX_NATIVE_REPLY_DEFER: - usleep_range(400, 500); + usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100); break; } } @@ -476,7 +478,7 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) * For now just defer for long enough to hopefully be * safe for all use-cases. */ - usleep_range(500, 600); + usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100); continue; default: @@ -506,7 +508,7 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) aux->i2c_defer_count++; if (defer_i2c < 7) defer_i2c++; - usleep_range(400, 500); + usleep_range(AUX_RETRY_INTERVAL, AUX_RETRY_INTERVAL + 100); continue; default: |