i2c: mxs: detect No Slave Ack on SELECT in PIO mode

i2cdetect scanned i2c bus slow because the i2c-mxs driver ignored the
NO_SLAVE_ACK bit during busy-waiting loop. Thanks to the patch, the
speedup happens.

Signed-off-by: Janusz Uzycki <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>
This commit is contained in:
Janusz Użycki 2014-09-23 12:48:26 +02:00 • committed by Wolfram Sang
commit 030f940a53

View file

@ -307,6 +307,9 @@ static int mxs_i2c_pio_wait_xfer_end(struct mxs_i2c_dev *i2c)
unsigned long timeout = jiffies + msecs_to_jiffies(1000);
while (readl(i2c->regs + MXS_I2C_CTRL0) & MXS_I2C_CTRL0_RUN) {
if (readl(i2c->regs + MXS_I2C_CTRL1) &
MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ)
return -ENXIO;
if (time_after(jiffies, timeout))
return -ETIMEDOUT;
cond_resched();