drm/i915/sdvo: Propagate i2c error from switching DDC control bus.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
This commit is contained in:
Chris Wilson 2010-09-14 19:11:56 +01:00
parent 9d1a903d4b
commit 819f3fb7fe
1 changed files with 18 additions and 9 deletions

View File

@ -530,8 +530,8 @@ static int intel_sdvo_get_pixel_multiplier(struct drm_display_mode *mode)
* another I2C transaction after issuing the DDC bus switch, it will be
* switched to the internal SDVO register.
*/
static void intel_sdvo_set_control_bus_switch(struct intel_sdvo *intel_sdvo,
u8 target)
static int intel_sdvo_set_control_bus_switch(struct intel_sdvo *intel_sdvo,
u8 target)
{
u8 out_buf[2], cmd_buf[2], ret_value[2], ret;
struct i2c_msg msgs[] = {
@ -557,9 +557,10 @@ static void intel_sdvo_set_control_bus_switch(struct intel_sdvo *intel_sdvo,
};
intel_sdvo_debug_write(intel_sdvo, SDVO_CMD_SET_CONTROL_BUS_SWITCH,
&target, 1);
&target, 1);
/* write the DDC switch command argument */
intel_sdvo_write_byte(intel_sdvo, SDVO_I2C_ARG_0, target);
if (!intel_sdvo_write_byte(intel_sdvo, SDVO_I2C_ARG_0, target))
return -EIO;
out_buf[0] = SDVO_I2C_OPCODE;
out_buf[1] = SDVO_CMD_SET_CONTROL_BUS_SWITCH;
@ -569,17 +570,20 @@ static void intel_sdvo_set_control_bus_switch(struct intel_sdvo *intel_sdvo,
ret_value[1] = 0;
ret = i2c_transfer(intel_sdvo->base.i2c_bus, msgs, 3);
if (ret < 0)
return ret;
if (ret != 3) {
/* failure in I2C transfer */
DRM_DEBUG_KMS("I2c transfer returned %d\n", ret);
return;
return -EIO;
}
if (ret_value[0] != SDVO_CMD_STATUS_SUCCESS) {
DRM_DEBUG_KMS("DDC switch command returns response %d\n",
ret_value[0]);
return;
ret_value[0]);
return -EIO;
}
return;
return 0;
}
static bool intel_sdvo_set_value(struct intel_sdvo *intel_sdvo, u8 cmd, const void *data, int len)
@ -1982,13 +1986,18 @@ static int intel_sdvo_master_xfer(struct i2c_adapter *i2c_adap,
{
struct intel_sdvo *intel_sdvo;
const struct i2c_algorithm *algo;
int ret;
intel_sdvo = container_of(i2c_adap->algo_data,
struct intel_sdvo,
base);
algo = intel_sdvo->base.i2c_bus->algo;
intel_sdvo_set_control_bus_switch(intel_sdvo, intel_sdvo->ddc_bus);
ret = intel_sdvo_set_control_bus_switch(intel_sdvo,
intel_sdvo->ddc_bus);
if (ret)
return ret;
return algo->master_xfer(i2c_adap, msgs, num);
}