summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorVille Syrjälä <ville.syrjala@linux.intel.com>2015-08-26 22:55:05 +0300
committerJani Nikula <jani.nikula@intel.com>2015-09-02 15:49:20 +0300
commit79a2b161c12a1b751f53a7698494cb722530bca5 (patch)
tree51475dc0effbcef25ba32d681de55e87eff8a3e1 /drivers
parentc4749c9a4a9ddc16200ce46a19078357727bf4b1 (diff)
downloadlinux-79a2b161c12a1b751f53a7698494cb722530bca5.tar.gz
linux-79a2b161c12a1b751f53a7698494cb722530bca5.tar.bz2
linux-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')
-rw-r--r--drivers/gpu/drm/drm_dp_helper.c8
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: