Re: [PATCH v5 2/2] iio: pressure: dps310: Reset chip if MEAS_CFG is corrupt

From: Eddie James
Date: Tue Sep 06 2022 - 15:42:06 EST



On 8/20/22 07:02, Jonathan Cameron wrote:
On Thu, 18 Aug 2022 23:16:55 +0300
Andy Shevchenko <andy.shevchenko@xxxxxxxxx> wrote:

On Mon, Aug 15, 2022 at 5:57 PM Eddie James <eajames@xxxxxxxxxxxxx> wrote:
Corruption of the MEAS_CFG register has been observed soon after
system boot. In order to recover this scenario, check MEAS_CFG if
measurement isn't ready, and if it's incorrect, reset the DPS310
and execute the startup procedure.
...

+ * Called with lock held. Returns a negative value on error, a positive value
+ * when the device is not ready, and zero when the device is ready.
Can we have

#define DPS310_DEVICE_NOT_READY 1

(or anonymous enum) and return it instead of abstract 1 or any other
positive number?
Perhaps make it even clearer by returning the need to wait via another parameter
rather than this being (probably) the only place in driver with a postive rc.

bool reset_done;

rc = dps310_check_reset_meas_cfg(data, DPS310_TMP_RDY, &reset_done);

if (reset_done) {
}


Thanks for the feedback.

Unfortunately our issue is still presenting itself even with a correct MEAS_CFG register. The sensor ready bit never gets set. So I'm going to rework this patch to reset the device after a timeout.


Thanks,

Eddie



...

+ rc = dps310_check_reset_meas_cfg(data, DPS310_TMP_RDY);
if (rc < 0)
goto done;

+ if (rc > 0) {
+ rate = dps310_get_temp_samp_freq(data);
+ timeout = DPS310_POLL_TIMEOUT_US(rate);
+
+ /*
+ * Poll for sensor readiness; base the timeout upon the sample
+ * rate.
+ */
+ rc = regmap_read_poll_timeout(data->regmap, DPS310_MEAS_CFG,
+ ready, ready & DPS310_TMP_RDY,
+ DPS310_POLL_SLEEP_US(timeout),
+ timeout);
+ if (rc)
+ goto done;
+ }
But have you tried to make a helper that takes a pointer to the
respective function?