drm/i915: Clarify error returns from display port aux channel I/O

Use distinct error return values for each kind of aux channel I/O failure.

Signed-off-by: Keith Packard <keithp@keithp.com>
This commit is contained in:
Keith Packard 2009-06-11 22:30:32 -07:00
parent b11248df4c
commit a5b3da543d

View file

@ -209,15 +209,19 @@ intel_dp_aux_ch(struct intel_output *intel_output,
if ((status & DP_AUX_CH_CTL_DONE) == 0) {
printk(KERN_ERR "dp_aux_ch not done status 0x%08x\n", status);
return -1;
return -EBUSY;
}
/* Check for timeout or receive error.
* Timeouts occur when the sink is not connected
*/
if (status & (DP_AUX_CH_CTL_TIME_OUT_ERROR | DP_AUX_CH_CTL_RECEIVE_ERROR)) {
printk(KERN_ERR "dp_aux_ch error status 0x%08x\n", status);
return -1;
if (status & DP_AUX_CH_CTL_RECEIVE_ERROR) {
printk(KERN_ERR "dp_aux_ch receive error status 0x%08x\n", status);
return -EIO;
}
if (status & DP_AUX_CH_CTL_TIME_OUT_ERROR) {
printk(KERN_ERR "dp_aux_ch timeout status 0x%08x\n", status);
return -ETIMEDOUT;
}
/* Unload any bytes sent back from the other side */
@ -263,7 +267,7 @@ intel_dp_aux_native_write(struct intel_output *intel_output,
else if ((ack & AUX_NATIVE_REPLY_MASK) == AUX_NATIVE_REPLY_DEFER)
udelay(100);
else
return -1;
return -EIO;
}
return send_bytes;
}
@ -299,7 +303,9 @@ intel_dp_aux_native_read(struct intel_output *intel_output,
for (;;) {
ret = intel_dp_aux_ch(intel_output, msg, msg_bytes,
reply, reply_bytes);
if (ret <= 0)
if (ret == 0)
return -EPROTO;
if (ret < 0)
return ret;
ack = reply[0];
if ((ack & AUX_NATIVE_REPLY_MASK) == AUX_NATIVE_REPLY_ACK) {
@ -309,7 +315,7 @@ intel_dp_aux_native_read(struct intel_output *intel_output,
else if ((ack & AUX_NATIVE_REPLY_MASK) == AUX_NATIVE_REPLY_DEFER)
udelay(100);
else
return -1;
return -EIO;
}
}