diff options
Diffstat (limited to 'drivers/gpu/drm/msm/dp/dp_link.c')
| -rw-r--r-- | drivers/gpu/drm/msm/dp/dp_link.c | 21 |
1 files changed, 12 insertions, 9 deletions
diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c index 36bb6191d2f0..f1f1d646539d 100644 --- a/drivers/gpu/drm/msm/dp/dp_link.c +++ b/drivers/gpu/drm/msm/dp/dp_link.c @@ -49,23 +49,26 @@ static int dp_aux_link_power_up(struct drm_dp_aux *aux, struct dp_link_info *link) { u8 value; - int err; + ssize_t len; + int i; if (link->revision < 0x11) return 0; - err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value); - if (err < 0) - return err; + len = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value); + if (len < 0) + return len; value &= ~DP_SET_POWER_MASK; value |= DP_SET_POWER_D0; - err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value); - if (err < 0) - return err; - - usleep_range(1000, 2000); + /* retry for 1ms to give the sink time to wake up */ + for (i = 0; i < 3; i++) { + len = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value); + usleep_range(1000, 2000); + if (len == 1) + break; + } return 0; } |