diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-bus-iio-adc-stm32 | 18 | ||||
| -rw-r--r-- | drivers/iio/adc/stm32-adc.c | 46 |
2 files changed, 63 insertions, 1 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-adc-stm32 new file mode 100644 index 000000000000..efe4c85e3c8b --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-adc-stm32 @@ -0,0 +1,18 @@ +What: /sys/bus/iio/devices/triggerX/trigger_polarity +KernelVersion: 4.11 +Contact: fabrice.gasnier@st.com +Description: + The STM32 ADC can be configured to use external trigger sources + (e.g. timers, pwm or exti gpio). Then, it can be tuned to start + conversions on external trigger by either: + - "rising-edge" + - "falling-edge" + - "both-edges". + Reading returns current trigger polarity. + Writing value before enabling conversions sets trigger polarity. + +What: /sys/bus/iio/devices/triggerX/trigger_polarity_available +KernelVersion: 4.11 +Contact: fabrice.gasnier@st.com +Description: + List all available trigger_polarity settings. diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 87d984ba4ef2..9a38f9a54451 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -135,6 +135,7 @@ struct stm32_adc_regs { * @lock: spinlock * @bufi: data buffer index * @num_conv: expected number of scan conversions + * @trigger_polarity: external trigger polarity (e.g. exten) */ struct stm32_adc { struct stm32_adc_common *common; @@ -146,6 +147,7 @@ struct stm32_adc { spinlock_t lock; /* interrupt lock */ unsigned int bufi; unsigned int num_conv; + u32 trigger_polarity; }; /** @@ -410,7 +412,7 @@ static int stm32_adc_set_trig(struct iio_dev *indio_dev, /* set trigger source and polarity (default to rising edge) */ extsel = ret; - exten = STM32_EXTEN_HWTRIG_RISING_EDGE; + exten = adc->trigger_polarity + STM32_EXTEN_HWTRIG_RISING_EDGE; } spin_lock_irqsave(&adc->lock, flags); @@ -424,6 +426,36 @@ 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->trigger_polarity = 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->trigger_polarity; +} + +static const char * const stm32_trig_pol_items[] = { + "rising-edge", "falling-edge", "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, +}; + /** * stm32_adc_single_conv() - Performs a single conversion * @indio_dev: IIO device @@ -682,6 +714,17 @@ static irqreturn_t stm32_adc_trigger_handler(int irq, void *p) return IRQ_HANDLED; } +static const struct iio_chan_spec_ext_info stm32_adc_ext_info[] = { + IIO_ENUM("trigger_polarity", IIO_SHARED_BY_ALL, &stm32_adc_trig_pol), + { + .name = "trigger_polarity_available", + .shared = IIO_SHARED_BY_ALL, + .read = iio_enum_available_read, + .private = (uintptr_t)&stm32_adc_trig_pol, + }, + {}, +}; + static void stm32_adc_chan_init_one(struct iio_dev *indio_dev, struct iio_chan_spec *chan, const struct stm32_adc_chan_spec *channel, @@ -697,6 +740,7 @@ static void stm32_adc_chan_init_one(struct iio_dev *indio_dev, chan->scan_type.sign = 'u'; chan->scan_type.realbits = 12; chan->scan_type.storagebits = 16; + chan->ext_info = stm32_adc_ext_info; } static int stm32_adc_chan_of_init(struct iio_dev *indio_dev) |