Hi Wolfram,
Thanks for the review.
On 02/27/2018 01:52 AM, Wolfram Sang wrote:
On Thu, Jan 18, 2018 at 05:39:24AM +0000, George Cherian wrote:
I2C bus enters the STOP condition after the DATA_DONE interrupt is raised.
Essentially the driver should be checking the bus state before sending
the next transaction.
Yes.
In case the next transaction is initiated while the
bus is busy, the prior transactions stop condition is not achieved.
I didn't fully get why you can't check the BUSY bit and wait a little
just before you push out the next message?
Yes, I am checking for the BUSY bit and looping.
Here for reference
+ while (last_msg && busy_timeout) {
+ status = xlp9xx_read_i2c_reg(priv, XLP9XX_I2C_STATUS);
+ if ((status & XLP9XX_I2C_STATUS_BUSY) == 0)
+ break;
+
+ busy_timeout--;
+ udelay(1);
+ }
+
+ if (!busy_timeout) {
+ dev_dbg(priv->dev, "i2c bus busy for too long after transfer\n");
+ return -EIO;
+ }
Did you mean to eliminate the udelay and use msleep?
In any case I will re-post another version of the patch, since
I have found some more issues and need to be fixed.
Add the check to make sure the bus is not busy before next transaction.
Regards,
-George
