From: Chris Lesiak chris.lesiak@licor.com
commit 84edec86f449adea9ee0b4912a79ab8d9d65abb7 upstream.
The datasheets have the following note for the conversion time specification: "This parameter is specified by design and/or characterization and it is not tested in production."
Parts have been seen that require more time to do 14-bit conversions for the relative humidity channel. The result is ENXIO due to the address phase of a transfer not getting an ACK.
Delay an additional 1 ms per conversion to allow for additional margin.
Fixes: 4839367d99e3 ("iio: humidity: add HDC100x support") Signed-off-by: Chris Lesiak chris.lesiak@licor.com Acked-by: Matt Ranostay matt.ranostay@konsulko.com Link: https://lore.kernel.org/r/20210614141820.2034827-1-chris.lesiak@licor.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/humidity/hdc100x.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/humidity/hdc100x.c b/drivers/iio/humidity/hdc100x.c index 273eb0612a5d..344fbefa88ae 100644 --- a/drivers/iio/humidity/hdc100x.c +++ b/drivers/iio/humidity/hdc100x.c @@ -32,6 +32,8 @@ #include <linux/iio/trigger_consumer.h> #include <linux/iio/triggered_buffer.h>
+#include <linux/time.h> + #define HDC100X_REG_TEMP 0x00 #define HDC100X_REG_HUMIDITY 0x01
@@ -173,7 +175,7 @@ static int hdc100x_get_measurement(struct hdc100x_data *data, struct iio_chan_spec const *chan) { struct i2c_client *client = data->client; - int delay = data->adc_int_us[chan->address]; + int delay = data->adc_int_us[chan->address] + 1*USEC_PER_MSEC; int ret; __be16 val;
@@ -330,7 +332,7 @@ static irqreturn_t hdc100x_trigger_handler(int irq, void *p) struct iio_dev *indio_dev = pf->indio_dev; struct hdc100x_data *data = iio_priv(indio_dev); struct i2c_client *client = data->client; - int delay = data->adc_int_us[0] + data->adc_int_us[1]; + int delay = data->adc_int_us[0] + data->adc_int_us[1] + 2*USEC_PER_MSEC; int ret;
/* dual read starts at temp register */