On Wed, 20 Nov 2019 15:47:51 +0100
Andrea Merello <andrea.merello@xxxxxxxxx> wrote:
> This patch introduces IIO_VAL_CHAR type for standard IIO attributes to
> allow for attributes that needs to be represented by character rather
> than a number. This is preparatory for introducing a new attribute whose
> purpose is to describe thermocouple type, that can be i.e. "J", "K", etc..
>
> The char-type value is stored in the first "value" integer that is passed
> to the .[read/write]_raw() callbacks.
>
> Note that in order to make it possible for the IIO core to correctly parse
> this type (actually, to avoid integer parsing), it became mandatory for
> any driver that wish to use IIO_VAL_CHAR on a writable attribute to
> implement .write_raw_get_fmt().
>
> Cc: Hartmut Knaack <knaack.h@xxxxxx>
> Cc: Lars-Peter Clausen <lars@xxxxxxxxxx>
> Cc: Peter Meerwald-Stadler <pmeerw@xxxxxxxxxx>
> Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> Cc: Patrick Havelange <patrick.havelange@xxxxxxxxxxxxx>
> Cc: Matt Weber <matthew.weber@xxxxxxxxxxxxxxxxxxx>
> Cc: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx>
> Cc: Chuhong Yuan <hslester96@xxxxxxxxx>
> Cc: Daniel Gomez <dagmcr@xxxxxxxxx>
> Cc: linux-iio@xxxxxxxxxxxxxxx
> Signed-off-by: Andrea Merello <andrea.merello@xxxxxxxxx>
applied. I dropped the RFC part though given it's going in ;)
Thanks,
Jonathan
> ---
> drivers/iio/industrialio-core.c | 22 ++++++++++++++++++----
> include/linux/iio/types.h | 1 +
> 2 files changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index f72c2dc5f703..958b5c48a86f 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -596,6 +596,8 @@ static ssize_t __iio_format_value(char *buf, size_t len, unsigned int type,
> }
> return l;
> }
> + case IIO_VAL_CHAR:
> + return snprintf(buf, len, "%c", (char)vals[0]);
> default:
> return 0;
> }
> @@ -837,7 +839,8 @@ static ssize_t iio_write_channel_info(struct device *dev,
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
> int ret, fract_mult = 100000;
> - int integer, fract;
> + int integer, fract = 0;
> + bool is_char = false;
>
> /* Assumes decimal - precision based on number of digits */
> if (!indio_dev->info->write_raw)
> @@ -855,13 +858,24 @@ static ssize_t iio_write_channel_info(struct device *dev,
> case IIO_VAL_INT_PLUS_NANO:
> fract_mult = 100000000;
> break;
> + case IIO_VAL_CHAR:
> + is_char = true;
> + break;
> default:
> return -EINVAL;
> }
>
> - ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
> - if (ret)
> - return ret;
> + if (is_char) {
> + char ch;
> +
> + if (sscanf(buf, "%c", &ch) != 1)
> + return -EINVAL;
> + integer = ch;
> + } else {
> + ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
> + if (ret)
> + return ret;
> + }
>
> ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
> integer, fract, this_attr->address);
> diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
> index fa824e160f35..8e0026da38c9 100644
> --- a/include/linux/iio/types.h
> +++ b/include/linux/iio/types.h
> @@ -25,6 +25,7 @@ enum iio_event_info {
> #define IIO_VAL_INT_MULTIPLE 5
> #define IIO_VAL_FRACTIONAL 10
> #define IIO_VAL_FRACTIONAL_LOG2 11
> +#define IIO_VAL_CHAR 12
>
> enum iio_available_type {
> IIO_AVAIL_LIST,
