iio: pressure: dps310: Adjust Timeout Settings

The DPS310 sensor chip has been encountering intermittent errors while
reading the sensor device across various system designs. This issue causes
the chip to become "stuck," preventing the indication of "ready" status
for pressure and temperature measurements in the MEAS_CFG register.

To address this issue, this commit fixes the timeout settings to improve
sensor stability:
- After sending a reset command to the chip, the timeout has been extended
  from 2.5 ms to 15 ms, aligning with the DPS310 specification.
- The read timeout value of the MEAS_CFG register has been adjusted from
  20ms to 30ms to match the specification.

Signed-off-by: Lakshmi Yadlapati <lakshmiy@us.ibm.com>
Fixes: 7b4ab4abcea4 ("iio: pressure: dps310: Reset chip after timeout")
Link: https://lore.kernel.org/r/20230829180222.3431926-2-lakshmiy@us.ibm.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c
index b10dbf5..1ff091b 100644 (file)
--- a/drivers/iio/pressure/dps310.c
+++ b/drivers/iio/pressure/dps310.c
@@ -57,8 +57,8 @@
 #define  DPS310_RESET_MAGIC    0x09
 #define DPS310_COEF_BASE       0x10
 
-/* Make sure sleep time is <= 20ms for usleep_range */
-#define DPS310_POLL_SLEEP_US(t)                min(20000, (t) / 8)
+/* Make sure sleep time is <= 30ms for usleep_range */
+#define DPS310_POLL_SLEEP_US(t)                min(30000, (t) / 8)
 /* Silently handle error in rate value here */
 #define DPS310_POLL_TIMEOUT_US(rc)     ((rc) <= 0 ? 1000000 : 1000000 / (rc))
 
@@ -402,8 +402,8 @@ static int dps310_reset_wait(struct dps310_data *data)
        if (rc)
                return rc;
 
-       /* Wait for device chip access: 2.5ms in specification */
-       usleep_range(2500, 12000);
+       /* Wait for device chip access: 15ms in specification */
+       usleep_range(15000, 55000);
        return 0;
 }