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| author | Jani Nikula <jani.nikula@intel.com> | 2015-03-17 18:18:54 +0300 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2015-03-20 13:48:11 +0300 |
| commit | a1ddefd8f3963cd9edfda86a0affff8e53d4a762 (patch) | |
| tree | 784a0a0c6aafac2aed7a32fc893ba1aa17e15abb | |
| parent | 94ca719ee47f287b11942c899e6b81045311b786 (diff) | |
| download | linux-a1ddefd8f3963cd9edfda86a0affff8e53d4a762.tar.xz | |
drm/i915/dp: return number of bytes written for short aux/i2c writes
Allow for a larger receive data size, and check if the receiver returned
the number of bytes written. Without this, we've basically skipped all
the unwritten bytes for short writes.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 5256c064da05..3967af10f53c 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -951,7 +951,7 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) case DP_AUX_NATIVE_WRITE: case DP_AUX_I2C_WRITE: txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE; - rxsize = 1; + rxsize = 2; /* 0 or 1 data bytes */ if (WARN_ON(txsize > 20)) return -E2BIG; @@ -962,8 +962,13 @@ intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) if (ret > 0) { msg->reply = rxbuf[0] >> 4; - /* Return payload size. */ - ret = msg->size; + if (ret > 1) { + /* Number of bytes written in a short write. */ + ret = clamp_t(int, rxbuf[1], 0, msg->size); + } else { + /* Return payload size. */ + ret = msg->size; + } } break; |