[PATCH v3 2/2] iio: stm32 trigger: Add counter enable modes

From: Benjamin Gaignard
Date: Mon Mar 27 2017 - 05:45:00 EST


Device counting could be controlled by the level or the edges of
a trigger.
in_count0_enable_mode attibute allow to set the control mode.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
---
.../ABI/testing/sysfs-bus-iio-timer-stm32 | 23 +++++++
drivers/iio/trigger/stm32-timer-trigger.c | 70 ++++++++++++++++++++++
2 files changed, 93 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
index bf795ad..c0a1edc 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
@@ -59,3 +59,26 @@ Description:
quadrature:
Encoder A and B inputs are mixed to get direction
and count with a scale of 0.25.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count_enable_mode_available
+KernelVersion: 4.12
+Contact: benjamin.gaignard@xxxxxx
+Description:
+ Reading returns the list possible enable modes.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count0_enable_mode
+KernelVersion: 4.12
+Contact: benjamin.gaignard@xxxxxx
+Description:
+ Configure the device counter enable modes, in all case
+ counting direction is set by in_count0_count_direction
+ attribute and the counter is clocked by the internal clock.
+ always:
+ Counter is always ON.
+
+ gated:
+ Counting is enabled when connected trigger signal
+ level is high else counting is disabled.
+
+ triggered:
+ Counting start on rising edge of the connected trigger.
diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
index 7db904c..0f1a2cf 100644
--- a/drivers/iio/trigger/stm32-timer-trigger.c
+++ b/drivers/iio/trigger/stm32-timer-trigger.c
@@ -353,6 +353,74 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,
.write_raw = stm32_counter_write_raw
};

+static const char *const stm32_enable_modes[] = {
+ "always",
+ "gated",
+ "triggered",
+};
+
+static int stm32_enable_mode2sms(int mode)
+{
+ switch (mode) {
+ case 0:
+ return 0;
+ case 1:
+ return 5;
+ case 2:
+ return 6;
+ }
+
+ return -EINVAL;
+}
+
+static int stm32_set_enable_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int mode)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ int sms = stm32_enable_mode2sms(mode);
+
+ if (sms < 0)
+ return sms;
+
+ regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms);
+
+ return 0;
+}
+
+static int stm32_sms2enable_mode(int mode)
+{
+ switch (mode) {
+ case 0:
+ return 0;
+ case 5:
+ return 1;
+ case 6:
+ return 2;
+ }
+
+ return -EINVAL;
+}
+
+static int stm32_get_enable_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ u32 smcr;
+
+ regmap_read(priv->regmap, TIM_SMCR, &smcr);
+ smcr &= TIM_SMCR_SMS;
+
+ return stm32_sms2enable_mode(smcr);
+}
+
+static const struct iio_enum stm32_enable_mode_enum = {
+ .items = stm32_enable_modes,
+ .num_items = ARRAY_SIZE(stm32_enable_modes),
+ .set = stm32_set_enable_mode,
+ .get = stm32_get_enable_mode
+};
+
static const char *const stm32_quadrature_modes[] = {
"channel_A",
"channel_B",
@@ -466,6 +534,8 @@ static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,
IIO_ENUM_AVAILABLE("count_direction", &stm32_count_direction_enum),
IIO_ENUM("quadrature_mode", IIO_SEPARATE, &stm32_quadrature_mode_enum),
IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_quadrature_mode_enum),
+ IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum),
+ IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum),
{}
};

--
1.9.1