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[0549/1094] drm/i915: support address only i2c-over-aux transactions

Message ID 1413889294-31328-550-git-send-email-dheerajx.s.jamwal@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Dheeraj Jamwal Oct. 21, 2014, 10:52 a.m. UTC 
From: Jani Nikula <jani.nikula@intel.com>

To support bare address requests used by the drm dp helpers.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
(cherry picked from commit a6c8aff022d4d06e4b41455ae9b2a5d3d503bf76)

Signed-off-by: Dheeraj Jamwal <dheerajx.s.jamwal@intel.com>
---
 drivers/gpu/drm/i915/intel_dp.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index a0dad1a..d2a5588 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -575,7 +575,8 @@  out:
 	return ret;
 }
 
-#define HEADER_SIZE	4
+#define BARE_ADDRESS_SIZE	3
+#define HEADER_SIZE		(BARE_ADDRESS_SIZE + 1)
 static ssize_t
 intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 {
@@ -592,7 +593,7 @@  intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 	switch (msg->request & ~DP_AUX_I2C_MOT) {
 	case DP_AUX_NATIVE_WRITE:
 	case DP_AUX_I2C_WRITE:
-		txsize = HEADER_SIZE + msg->size;
+		txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
 		rxsize = 1;
 
 		if (WARN_ON(txsize > 20))
@@ -611,7 +612,7 @@  intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
 
 	case DP_AUX_NATIVE_READ:
 	case DP_AUX_I2C_READ:
-		txsize = HEADER_SIZE;
+		txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
 		rxsize = msg->size + 1;
 
 		if (WARN_ON(rxsize > 20))