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Subject[PATCH 2/2] iio: hx711: fix bug in reset functionality
return value in hx711_reset() should indicate status of dout
otherwise the calling function is reporting an error als false positive

wait up to 1 second until the device is in normal state;
by changing the channel on every trigger event it turned out that the
former 100 ms are not enough for waiting until the device is in normal mode

Signed-off-by: Andreas Klinger <ak@it-klinger.de>
---
drivers/iio/adc/hx711.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/adc/hx711.c b/drivers/iio/adc/hx711.c
index d773fd69a76d..eabd2e66aca3 100644
--- a/drivers/iio/adc/hx711.c
+++ b/drivers/iio/adc/hx711.c
@@ -153,15 +153,16 @@ static int hx711_wait_for_ready(struct hx711_data *hx711_data)
int i, val;

/*
- * a maximum reset cycle time of 56 ms was measured.
- * we round it up to 100 ms
+ * in some rare cases the reset takes quite a long time
+ * especially when the channel is changed.
+ * Allow up to one second for it
*/
for (i = 0; i < 100; i++) {
val = gpiod_get_value(hx711_data->gpiod_dout);
if (!val)
break;
- /* sleep at least 1 ms */
- msleep(1);
+ /* sleep at least 10 ms */
+ msleep(10);
}
if (val)
return -EIO;
@@ -203,9 +204,7 @@ static int hx711_reset(struct hx711_data *hx711_data)
* after a dummy read we need to wait vor readiness
* for not mixing gain pulses with the clock
*/
- ret = hx711_wait_for_ready(hx711_data);
- if (ret)
- return ret;
+ val = hx711_wait_for_ready(hx711_data);
}

return val;
--
2.1.4

--

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