On Thu, Oct 18, 2018 at 12:10:32PM +0300, Stefan Popa wrote:
> +static int ad7606_read_samples(struct ad7606_state *st)
> +{
> + unsigned int num = st->chip_info->num_channels;
> + u16 *data = st->data;
> + int ret;
> +
> + /*
> + * The frstdata signal is set to high while and after reading the sample
> + * of the first channel and low for all other channels. This can be used
> + * to check that the incoming data is correctly aligned. During normal
> + * operation the data should never become unaligned, but some glitch or
> + * electrostatic discharge might cause an extra read or clock cycle.
> + * Monitoring the frstdata signal allows to recover from such failure
> + * situations.
> + */
> +
> + if (st->gpio_frstdata) {
> + ret = st->bops->read_block(st->dev, 1, data);
> + if (ret)
> + return ret;
> +
> + if (!gpiod_get_value(st->gpio_frstdata)) {
This check should maybe be:
if (gpiod_get_value(st->gpio_frstdata) <= 0) {
(Or possibly not, I don't know the code very well).
> + ad7606_reset(st);
> + return -EIO;
> + }
> +
> + data++;
> + num--;
> + }
> +
> + return st->bops->read_block(st->dev, num, data);
> +}
regards,
dan carpenter
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
