| Message ID | 1503413631-18438-4-git-send-email-shashank.sharma@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/gpu/drm/drm_dp_dual_mode_helper.c b/drivers/gpu/drm/drm_dp_dual_mode_helper.c index fc8c7ac..bb34ff8 100644 --- a/drivers/gpu/drm/drm_dp_dual_mode_helper.c +++ b/drivers/gpu/drm/drm_dp_dual_mode_helper.c @@ -75,8 +75,15 @@ ssize_t drm_dp_dual_mode_read(struct i2c_adapter *adapter, }, }; int ret; + int retry; + + for (retry = 5; ; retry--) { + ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); + if (ret > 0 || !retry) + break; + usleep_range(500, 1000); + } - ret = i2c_transfer(adapter, msgs, ARRAY_SIZE(msgs)); if (ret < 0) return ret; if (ret != ARRAY_SIZE(msgs))
From the CI builds, its been observed that during a driver reload/insert, dp dual mode read function sometimes fails to read from dual mode devices (like LSPCON) over i2c-over-aux channel. This patch adds some delay and few retries, allowing a scope for these devices to settle down. V3: Introduced this patch Cc: Ville Syrjala <ville.syrjala@linux.intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Shashank Sharma <shashank.sharma@intel.com> --- drivers/gpu/drm/drm_dp_dual_mode_helper.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)