[PATCH 6.6 242/396] iio: accel: adxl367: fix DEVID read after reset

Greg Kroah-Hartman
2024-04-01T16:48:30Z

From: Cosmin Tanislav <demonsingur@gmail.com>

commit 1b926914bbe4e30cb32f268893ef7d82a85275b8 upstream.

regmap_read_poll_timeout() will not sleep before reading,
causing the first read to return -ENXIO on I2C, since the
chip does not respond to it while it is being reset.

The datasheet specifies that a soft reset operation has a
latency of 7.5ms.

Add a 15ms sleep between reset and reading the DEVID register,
and switch to a simple regmap_read() call.

Fixes: cbab791c5e2a ("iio: accel: add ADXL367 driver")
Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240207033657.206171-1-demonsingur@gmail.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/iio/accel/adxl367.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/iio/accel/adxl367.c
+++ b/drivers/iio/accel/adxl367.c
@@ -1429,9 +1429,11 @@ static int adxl367_verify_devid(struct a
unsigned int val;
int ret;

- ret = regmap_read_poll_timeout(st->regmap, ADXL367_REG_DEVID, val,
- val == ADXL367_DEVID_AD, 1000, 10000);
+ ret = regmap_read(st->regmap, ADXL367_REG_DEVID, &val);
if (ret)
+ return dev_err_probe(st->dev, ret, "Failed to read dev id\n");
+
+ if (val != ADXL367_DEVID_AD)
return dev_err_probe(st->dev, -ENODEV,
"Invalid dev id 0x%02X, expected 0x%02X\n",
val, ADXL367_DEVID_AD);
@@ -1510,6 +1512,8 @@ int adxl367_probe(struct device *dev, co
if (ret)
return ret;

+ fsleep(15000);
+
ret = adxl367_verify_devid(st);
if (ret)
return ret;