drm/i915: support address only i2c-over-aux transactions

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

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This commit is contained in:
Jani Nikula 2014-04-07 12:37:25 +03:00 committed by Christian König
parent 1ca2030563
commit a6c8aff022

View file

@ -575,7 +575,8 @@ out:
return ret; return ret;
} }
#define HEADER_SIZE 4 #define BARE_ADDRESS_SIZE 3
#define HEADER_SIZE (BARE_ADDRESS_SIZE + 1)
static ssize_t static ssize_t
intel_dp_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) 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) { switch (msg->request & ~DP_AUX_I2C_MOT) {
case DP_AUX_NATIVE_WRITE: case DP_AUX_NATIVE_WRITE:
case DP_AUX_I2C_WRITE: case DP_AUX_I2C_WRITE:
txsize = HEADER_SIZE + msg->size; txsize = msg->size ? HEADER_SIZE + msg->size : BARE_ADDRESS_SIZE;
rxsize = 1; rxsize = 1;
if (WARN_ON(txsize > 20)) 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_NATIVE_READ:
case DP_AUX_I2C_READ: case DP_AUX_I2C_READ:
txsize = HEADER_SIZE; txsize = msg->size ? HEADER_SIZE : BARE_ADDRESS_SIZE;
rxsize = msg->size + 1; rxsize = msg->size + 1;
if (WARN_ON(rxsize > 20)) if (WARN_ON(rxsize > 20))