On Sun, Nov 18, 2018 at 10:57:57PM +0100, Andreas Kemnade wrote: > The api forbids writing data there otherwise. Prepare for the > serdev_open()/close() being a part of runtime pm. > > Signed-off-by: Andreas Kemnade <andreas@xxxxxxxxxxxx> > --- > drivers/gnss/sirf.c | 16 +++++++++++++++- > 1 file changed, 15 insertions(+), 1 deletion(-) > @@ -73,6 +76,7 @@ static void sirf_close(struct gnss_device *gdev) > serdev_device_close(serdev); > > pm_runtime_put(&serdev->dev); > + data->opened = false; > } > > static int sirf_write_raw(struct gnss_device *gdev, const unsigned char *buf, > @@ -105,7 +109,17 @@ static int sirf_receive_buf(struct serdev_device *serdev, > struct sirf_data *data = serdev_device_get_drvdata(serdev); > struct gnss_device *gdev = data->gdev; > > - return gnss_insert_raw(gdev, buf, count); > + /* > + * we might come here everytime when runtime is resumed > + * and data is received. Two cases are possible > + * 1. device is opened during initialisation > + * 2. kernel is compiled without runtime pm > + * and device is opened all the time > + */ > + if (data->opened) > + return gnss_insert_raw(gdev, buf, count); This can race with sirf_close() when you move serdev handling out of sirf_open()/close(). Not sure how best to handle that yet. Johan
