On 25/10/16 17:25, Fabrice Gasnier wrote:
> Add trigger polarity extended attribute.
>
> Signed-off-by: Fabrice Gasnier <fabrice.gasn...@st.com>
ABI always needs documenting. Add docs also makes it easy to review
without diving into the code.
This will also need a convincing argument for why it doesn't belong in the
device tree.
J
> ---
> drivers/iio/adc/stm32/stm32-adc.c | 41
> ++++++++++++++++++++++++++++++++++++-
> drivers/iio/adc/stm32/stm32-adc.h | 4 ++++
> drivers/iio/adc/stm32/stm32f4-adc.c | 12 +++++++++++
> 3 files changed, 56 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/adc/stm32/stm32-adc.c
> b/drivers/iio/adc/stm32/stm32-adc.c
> index 1a13450..9b4b459 100644
> --- a/drivers/iio/adc/stm32/stm32-adc.c
> +++ b/drivers/iio/adc/stm32/stm32-adc.c
> @@ -207,7 +207,11 @@ static int stm32_adc_set_trig(struct iio_dev *indio_dev,
>
> /* trigger source */
> extsel = trig_info[ret].extsel;
> - exten = STM32_EXTEN_HWTRIG_RISING_EDGE;
> +
> + /* default to rising edge if no polarity */
> + if (adc->exten == STM32_EXTEN_SWTRIG)
> + adc->exten = STM32_EXTEN_HWTRIG_RISING_EDGE;
> + exten = adc->exten;
> }
>
> spin_lock_irqsave(&adc->lock, flags);
> @@ -221,6 +225,40 @@ static int stm32_adc_set_trig(struct iio_dev *indio_dev,
> return 0;
> }
>
> +static int stm32_adc_set_trig_pol(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan,
> + unsigned int type)
> +{
> + struct stm32_adc *adc = iio_priv(indio_dev);
> +
> + adc->exten = type;
> +
> + return 0;
> +}
> +
> +static int stm32_adc_get_trig_pol(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan)
> +{
> + struct stm32_adc *adc = iio_priv(indio_dev);
> +
> + return adc->exten;
> +}
> +
> +static const char * const stm32_trig_pol_items[] = {
> + [STM32_EXTEN_SWTRIG] = "swtrig",
> + [STM32_EXTEN_HWTRIG_RISING_EDGE] = "rising-edge",
> + [STM32_EXTEN_HWTRIG_FALLING_EDGE] = "falling-edge",
> + [STM32_EXTEN_HWTRIG_BOTH_EDGES] = "both-edges",
> +};
> +
> +const struct iio_enum stm32_adc_trig_pol = {
> + .items = stm32_trig_pol_items,
> + .num_items = ARRAY_SIZE(stm32_trig_pol_items),
> + .get = stm32_adc_get_trig_pol,
> + .set = stm32_adc_set_trig_pol,
> +};
> +EXPORT_SYMBOL_GPL(stm32_adc_trig_pol);
> +
> /**
> * stm32_adc_conv_irq_enable() - Unmask end of conversion irq
> * @adc: stm32 adc instance
> @@ -893,6 +931,7 @@ static void stm32_adc_chan_init_one(struct iio_dev
> *indio_dev,
> chan->scan_type.realbits = adc->common->data->highres;
> chan->scan_type.storagebits = STM32_STORAGEBITS;
> chan->scan_type.shift = 0;
> + chan->ext_info = adc->common->data->ext_info;
> }
>
> static int stm32_adc_chan_of_init(struct iio_dev *indio_dev,
> diff --git a/drivers/iio/adc/stm32/stm32-adc.h
> b/drivers/iio/adc/stm32/stm32-adc.h
> index fe3568b..6c9b70d 100644
> --- a/drivers/iio/adc/stm32/stm32-adc.h
> +++ b/drivers/iio/adc/stm32/stm32-adc.h
> @@ -234,6 +234,7 @@ struct stm32_adc_reginfo {
> * @ext_triggers: Reference to trigger info for regular channels
> * @jext_triggers: Reference to trigger info for injected channels
> * @adc_reginfo: stm32 ADC registers description
> + * @ext_info: Extended channel info
> * @highres: Max resolution
> * @max_clock_rate: Max input clock rate
> * @clk_sel: routine to select common clock and prescaler
> @@ -251,6 +252,7 @@ struct stm32_adc_ops {
> const struct stm32_adc_trig_info *ext_triggers;
> const struct stm32_adc_trig_info *jext_triggers;
> const struct stm32_adc_reginfo *adc_reginfo;
> + const struct iio_chan_spec_ext_info *ext_info;
> int highres;
> unsigned long max_clock_rate;
> int (*clk_sel)(struct stm32_adc *adc);
> @@ -273,6 +275,7 @@ struct stm32_adc_ops {
> * @id: ADC instance number (e.g. adc 1, 2 or 3)
> * @offset: ADC instance register offset in ADC block
> * @max_channels: Max channels number for this ADC.
> + * @exten: External trigger config (enable/polarity)
> * @extrig_list: External trigger list (for regular channel)
> * @completion: end of single conversion completion
> * @buffer: data buffer
> @@ -295,6 +298,7 @@ struct stm32_adc {
> int id;
> int offset;
> int max_channels;
> + enum stm32_adc_exten exten;
> struct list_head extrig_list;
> struct completion completion;
> u16 *buffer;
> diff --git a/drivers/iio/adc/stm32/stm32f4-adc.c
> b/drivers/iio/adc/stm32/stm32f4-adc.c
> index 4d7a2a8..e033a68 100644
> --- a/drivers/iio/adc/stm32/stm32f4-adc.c
> +++ b/drivers/iio/adc/stm32/stm32f4-adc.c
> @@ -555,11 +555,23 @@ static int stm32f4_adc_clk_sel(struct stm32_adc *adc)
> return 0;
> }
>
> +static const struct iio_chan_spec_ext_info stm32f4_adc_ext_info[] = {
> + IIO_ENUM("trigger_pol", IIO_SHARED_BY_ALL, &stm32_adc_trig_pol),
> + {
> + .name = "trigger_pol_available",
> + .shared = IIO_SHARED_BY_ALL,
> + .read = iio_enum_available_read,
> + .private = (uintptr_t)&stm32_adc_trig_pol,
> + },
> + {},
> +};
> +
> static const struct stm32_adc_ops stm32f4_adc_ops = {
> .adc_info = stm32f4_adc_info,
> .ext_triggers = stm32f4_adc_ext_triggers,
> .jext_triggers = stm32f4_adc_jext_triggers,
> .adc_reginfo = &stm32f4_adc_reginfo,
> + .ext_info = stm32f4_adc_ext_info,
> .highres = 12,
> .max_clock_rate = 36000000,
> .clk_sel = stm32f4_adc_clk_sel,
>
