From: Ville Syrjälä ville.syrjala@linux.intel.com
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 --- drivers/gpu/drm/drm_dp_helper.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c index 80a02a4..7069e54 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: