xfer_read() waits for the HDMI I2C transaction to reach I2C_TRANSACTION_DONE, but it ignores both timeout and signal returns from wait_for_completion_interruptible_timeout(). If the interrupt never advances the transaction state, the loop can wait forever.
Return -ETIMEDOUT when the completion wait expires, propagate interrupted waits, and make the I2C master_xfer callback return the first transfer error instead of reporting a successful message count. Signed-off-by: Pengpeng Hou <[email protected]> --- drivers/gpu/drm/gma500/oaktrail_hdmi_i2c.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/gma500/oaktrail_hdmi_i2c.c b/drivers/gpu/drm/gma500/oaktrail_hdmi_i2c.c index 2a7916ca5..a780643f2 100644 --- a/drivers/gpu/drm/gma500/oaktrail_hdmi_i2c.c +++ b/drivers/gpu/drm/gma500/oaktrail_hdmi_i2c.c @@ -98,6 +98,7 @@ static int xfer_read(struct i2c_adapter *adap, struct i2c_msg *pmsg) struct oaktrail_hdmi_dev *hdmi_dev = i2c_get_adapdata(adap); struct hdmi_i2c_dev *i2c_dev = hdmi_dev->i2c_dev; u32 temp; + int ret; i2c_dev->status = I2C_STAT_INIT; i2c_dev->msg = pmsg; @@ -109,9 +110,14 @@ static int xfer_read(struct i2c_adapter *adap, struct i2c_msg *pmsg) HDMI_WRITE(HDMI_HI2CHCR, temp); HDMI_READ(HDMI_HI2CHCR); - while (i2c_dev->status != I2C_TRANSACTION_DONE) - wait_for_completion_interruptible_timeout(&i2c_dev->complete, + while (i2c_dev->status != I2C_TRANSACTION_DONE) { + ret = wait_for_completion_interruptible_timeout(&i2c_dev->complete, 10 * HZ); + if (ret < 0) + return ret; + if (!ret) + return -ETIMEDOUT; + } return 0; } @@ -130,7 +136,7 @@ static int oaktrail_hdmi_i2c_access(struct i2c_adapter *adap, { struct oaktrail_hdmi_dev *hdmi_dev = i2c_get_adapdata(adap); struct hdmi_i2c_dev *i2c_dev = hdmi_dev->i2c_dev; - int i; + int i, ret = 0; mutex_lock(&i2c_dev->i2c_lock); @@ -142,9 +148,11 @@ static int oaktrail_hdmi_i2c_access(struct i2c_adapter *adap, for (i = 0; i < num; i++) { if (pmsg->len && pmsg->buf) { if (pmsg->flags & I2C_M_RD) - xfer_read(adap, pmsg); + ret = xfer_read(adap, pmsg); else - xfer_write(adap, pmsg); + ret = xfer_write(adap, pmsg); + if (ret) + break; } pmsg++; /* next message */ } @@ -154,6 +162,9 @@ static int oaktrail_hdmi_i2c_access(struct i2c_adapter *adap, mutex_unlock(&i2c_dev->i2c_lock); + if (ret) + return ret; + return i; } -- 2.50.1 (Apple Git-155)
