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authorPaul Mundt <lethal@linux-sh.org>2011-01-06 09:27:34 (GMT)
committerPaul Mundt <lethal@linux-sh.org>2011-01-06 09:27:34 (GMT)
commit1928e87bcf185f56008d0746f887b691c1cb8c4a (patch)
treebc8db9e9cb40b73742d05e2e68189bd647687249 /drivers/gpu/drm/i915/intel_dp.c
parentca9c20ce2b383032b71bdae9ec0b468d428ca8d4 (diff)
parent3c0eee3fe6a3a1c745379547c7e7c904aa64f6d5 (diff)
downloadlinux-fsl-qoriq-1928e87bcf185f56008d0746f887b691c1cb8c4a.tar.xz
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts: drivers/video/sh_mobile_lcdcfb.c Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
-rw-r--r--drivers/gpu/drm/i915/intel_dp.c37
1 files changed, 30 insertions, 7 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index df648cb..864417c 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -479,6 +479,7 @@ intel_dp_i2c_aux_ch(struct i2c_adapter *adapter, int mode,
uint16_t address = algo_data->address;
uint8_t msg[5];
uint8_t reply[2];
+ unsigned retry;
int msg_bytes;
int reply_bytes;
int ret;
@@ -513,14 +514,33 @@ intel_dp_i2c_aux_ch(struct i2c_adapter *adapter, int mode,
break;
}
- for (;;) {
- ret = intel_dp_aux_ch(intel_dp,
- msg, msg_bytes,
- reply, reply_bytes);
+ for (retry = 0; retry < 5; retry++) {
+ ret = intel_dp_aux_ch(intel_dp,
+ msg, msg_bytes,
+ reply, reply_bytes);
if (ret < 0) {
DRM_DEBUG_KMS("aux_ch failed %d\n", ret);
return ret;
}
+
+ switch (reply[0] & AUX_NATIVE_REPLY_MASK) {
+ case AUX_NATIVE_REPLY_ACK:
+ /* I2C-over-AUX Reply field is only valid
+ * when paired with AUX ACK.
+ */
+ break;
+ case AUX_NATIVE_REPLY_NACK:
+ DRM_DEBUG_KMS("aux_ch native nack\n");
+ return -EREMOTEIO;
+ case AUX_NATIVE_REPLY_DEFER:
+ udelay(100);
+ continue;
+ default:
+ DRM_ERROR("aux_ch invalid native reply 0x%02x\n",
+ reply[0]);
+ return -EREMOTEIO;
+ }
+
switch (reply[0] & AUX_I2C_REPLY_MASK) {
case AUX_I2C_REPLY_ACK:
if (mode == MODE_I2C_READ) {
@@ -528,17 +548,20 @@ intel_dp_i2c_aux_ch(struct i2c_adapter *adapter, int mode,
}
return reply_bytes - 1;
case AUX_I2C_REPLY_NACK:
- DRM_DEBUG_KMS("aux_ch nack\n");
+ DRM_DEBUG_KMS("aux_i2c nack\n");
return -EREMOTEIO;
case AUX_I2C_REPLY_DEFER:
- DRM_DEBUG_KMS("aux_ch defer\n");
+ DRM_DEBUG_KMS("aux_i2c defer\n");
udelay(100);
break;
default:
- DRM_ERROR("aux_ch invalid reply 0x%02x\n", reply[0]);
+ DRM_ERROR("aux_i2c invalid reply 0x%02x\n", reply[0]);
return -EREMOTEIO;
}
}
+
+ DRM_ERROR("too many retries, giving up\n");
+ return -EREMOTEIO;
}
static int