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>
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 @@
}
EXPORT_SYMBOL(drm_dp_bw_code_to_link_rate);
+#define AUX_RETRY_INTERVAL 500 /* us */
+
/**
* DOC: dp helpers
*
@@ -213,7 +215,7 @@
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 @@
* 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 @@
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: