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-rw-r--r--Documentation/ABI/testing/sysfs-bus-iio-timer-stm3246
-rw-r--r--drivers/iio/trigger/stm32-timer-trigger.c244
-rw-r--r--include/linux/mfd/stm32-timers.h2
3 files changed, 282 insertions, 10 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
index 6534a60037ff..a55ad44446c5 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
+++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
@@ -3,11 +3,15 @@ KernelVersion: 4.11
Contact: benjamin.gaignard@st.com
Description:
Reading returns the list possible master modes which are:
- - "reset" : The UG bit from the TIMx_EGR register is used as trigger output (TRGO).
- - "enable" : The Counter Enable signal CNT_EN is used as trigger output.
+ - "reset" : The UG bit from the TIMx_EGR register is
+ used as trigger output (TRGO).
+ - "enable" : The Counter Enable signal CNT_EN is used
+ as trigger output.
- "update" : The update event is selected as trigger output.
- For instance a master timer can then be used as a prescaler for a slave timer.
- - "compare_pulse" : The trigger output send a positive pulse when the CC1IF flag is to be set.
+ For instance a master timer can then be used
+ as a prescaler for a slave timer.
+ - "compare_pulse" : The trigger output send a positive pulse
+ when the CC1IF flag is to be set.
- "OC1REF" : OC1REF signal is used as trigger output.
- "OC2REF" : OC2REF signal is used as trigger output.
- "OC3REF" : OC3REF signal is used as trigger output.
@@ -27,3 +31,37 @@ Description:
Reading returns the current sampling frequency.
Writing an value different of 0 set and start sampling.
Writing 0 stop sampling.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count0_preset
+KernelVersion: 4.12
+Contact: benjamin.gaignard@st.com
+Description:
+ Reading returns the current preset value.
+ Writing sets the preset value.
+ When counting up the counter starts from 0 and fires an
+ event when reach preset value.
+ When counting down the counter start from preset value
+ and fire event when reach 0.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count_quadrature_mode_available
+KernelVersion: 4.12
+Contact: benjamin.gaignard@st.com
+Description:
+ Reading returns the list possible quadrature modes.
+
+What: /sys/bus/iio/devices/iio:deviceX/in_count0_quadrature_mode
+KernelVersion: 4.12
+Contact: benjamin.gaignard@st.com
+Description:
+ Configure the device counter quadrature modes:
+ channel_A:
+ Encoder A input servers as the count input and B as
+ the UP/DOWN direction control input.
+
+ channel_B:
+ Encoder B input serves as the count input and A as
+ the UP/DOWN direction control input.
+
+ quadrature:
+ Encoder A and B inputs are mixed to get direction
+ and count with a scale of 0.25.
diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
index 994b96d19750..7db904cae926 100644
--- a/drivers/iio/trigger/stm32-timer-trigger.c
+++ b/drivers/iio/trigger/stm32-timer-trigger.c
@@ -15,6 +15,7 @@
#include <linux/platform_device.h>
#define MAX_TRIGGERS 6
+#define MAX_VALIDS 5
/* List the triggers created by each timer */
static const void *triggers_table[][MAX_TRIGGERS] = {
@@ -32,12 +33,29 @@ static const void *triggers_table[][MAX_TRIGGERS] = {
{ TIM12_TRGO, TIM12_CH1, TIM12_CH2,},
};
+/* List the triggers accepted by each timer */
+static const void *valids_table[][MAX_VALIDS] = {
+ { TIM5_TRGO, TIM2_TRGO, TIM3_TRGO, TIM4_TRGO,},
+ { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,},
+ { TIM1_TRGO, TIM2_TRGO, TIM5_TRGO, TIM4_TRGO,},
+ { TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO,},
+ { TIM2_TRGO, TIM3_TRGO, TIM4_TRGO, TIM8_TRGO,},
+ { }, /* timer 6 */
+ { }, /* timer 7 */
+ { TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO,},
+ { TIM2_TRGO, TIM3_TRGO,},
+ { }, /* timer 10 */
+ { }, /* timer 11 */
+ { TIM4_TRGO, TIM5_TRGO,},
+};
+
struct stm32_timer_trigger {
struct device *dev;
struct regmap *regmap;
struct clk *clk;
u32 max_arr;
const void *triggers;
+ const void *valids;
};
static int stm32_timer_start(struct stm32_timer_trigger *priv,
@@ -180,8 +198,7 @@ static ssize_t stm32_tt_show_master_mode(struct device *dev,
struct device_attribute *attr,
char *buf)
{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ struct stm32_timer_trigger *priv = dev_get_drvdata(dev);
u32 cr2;
regmap_read(priv->regmap, TIM_CR2, &cr2);
@@ -194,8 +211,7 @@ static ssize_t stm32_tt_store_master_mode(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t len)
{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ struct stm32_timer_trigger *priv = dev_get_drvdata(dev);
int i;
for (i = 0; i < ARRAY_SIZE(master_mode_table); i++) {
@@ -275,6 +291,216 @@ static int stm32_setup_iio_triggers(struct stm32_timer_trigger *priv)
return 0;
}
+static int stm32_counter_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ {
+ u32 cnt;
+
+ regmap_read(priv->regmap, TIM_CNT, &cnt);
+ *val = cnt;
+
+ return IIO_VAL_INT;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ {
+ u32 smcr;
+
+ regmap_read(priv->regmap, TIM_SMCR, &smcr);
+ smcr &= TIM_SMCR_SMS;
+
+ *val = 1;
+ *val2 = 0;
+
+ /* in quadrature case scale = 0.25 */
+ if (smcr == 3)
+ *val2 = 2;
+
+ return IIO_VAL_FRACTIONAL_LOG2;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int stm32_counter_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ regmap_write(priv->regmap, TIM_CNT, val);
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ /* fixed scale */
+ return -EINVAL;
+ }
+
+ return -EINVAL;
+}
+
+static const struct iio_info stm32_trigger_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = stm32_counter_read_raw,
+ .write_raw = stm32_counter_write_raw
+};
+
+static const char *const stm32_quadrature_modes[] = {
+ "channel_A",
+ "channel_B",
+ "quadrature",
+};
+
+static int stm32_set_quadrature_mode(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int mode)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+
+ regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, mode + 1);
+
+ return 0;
+}
+
+static int stm32_get_quadrature_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 smcr - 1;
+}
+
+static const struct iio_enum stm32_quadrature_mode_enum = {
+ .items = stm32_quadrature_modes,
+ .num_items = ARRAY_SIZE(stm32_quadrature_modes),
+ .set = stm32_set_quadrature_mode,
+ .get = stm32_get_quadrature_mode
+};
+
+static const char *const stm32_count_direction_states[] = {
+ "up",
+ "down"
+};
+
+static int stm32_set_count_direction(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int mode)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_DIR, mode);
+
+ return 0;
+}
+
+static int stm32_get_count_direction(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ u32 cr1;
+
+ regmap_read(priv->regmap, TIM_CR1, &cr1);
+
+ return (cr1 & TIM_CR1_DIR);
+}
+
+static const struct iio_enum stm32_count_direction_enum = {
+ .items = stm32_count_direction_states,
+ .num_items = ARRAY_SIZE(stm32_count_direction_states),
+ .set = stm32_set_count_direction,
+ .get = stm32_get_count_direction
+};
+
+static ssize_t stm32_count_get_preset(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ char *buf)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ u32 arr;
+
+ regmap_read(priv->regmap, TIM_ARR, &arr);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", arr);
+}
+
+static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ const char *buf, size_t len)
+{
+ struct stm32_timer_trigger *priv = iio_priv(indio_dev);
+ unsigned int preset;
+ int ret;
+
+ ret = kstrtouint(buf, 0, &preset);
+ if (ret)
+ return ret;
+
+ regmap_write(priv->regmap, TIM_ARR, preset);
+ regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE);
+
+ return len;
+}
+
+static const struct iio_chan_spec_ext_info stm32_trigger_count_info[] = {
+ {
+ .name = "preset",
+ .shared = IIO_SEPARATE,
+ .read = stm32_count_get_preset,
+ .write = stm32_count_set_preset
+ },
+ IIO_ENUM("count_direction", IIO_SEPARATE, &stm32_count_direction_enum),
+ 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),
+ {}
+};
+
+static const struct iio_chan_spec stm32_trigger_channel = {
+ .type = IIO_COUNT,
+ .channel = 0,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+ .ext_info = stm32_trigger_count_info,
+ .indexed = 1
+};
+
+static struct stm32_timer_trigger *stm32_setup_counter_device(struct device *dev)
+{
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev,
+ sizeof(struct stm32_timer_trigger));
+ if (!indio_dev)
+ return NULL;
+
+ indio_dev->name = dev_name(dev);
+ indio_dev->dev.parent = dev;
+ indio_dev->info = &stm32_trigger_info;
+ indio_dev->num_channels = 1;
+ indio_dev->channels = &stm32_trigger_channel;
+ indio_dev->dev.of_node = dev->of_node;
+
+ ret = devm_iio_device_register(dev, indio_dev);
+ if (ret)
+ return NULL;
+
+ return iio_priv(indio_dev);
+}
+
/**
* is_stm32_timer_trigger
* @trig: trigger to be checked
@@ -299,10 +525,15 @@ static int stm32_timer_trigger_probe(struct platform_device *pdev)
if (of_property_read_u32(dev->of_node, "reg", &index))
return -EINVAL;
- if (index >= ARRAY_SIZE(triggers_table))
+ if (index >= ARRAY_SIZE(triggers_table) ||
+ index >= ARRAY_SIZE(valids_table))
return -EINVAL;
- priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ /* Create an IIO device only if we have triggers to be validated */
+ if (*valids_table[index])
+ priv = stm32_setup_counter_device(dev);
+ else
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
@@ -312,6 +543,7 @@ static int stm32_timer_trigger_probe(struct platform_device *pdev)
priv->clk = ddata->clk;
priv->max_arr = ddata->max_arr;
priv->triggers = triggers_table[index];
+ priv->valids = valids_table[index];
ret = stm32_setup_iio_triggers(priv);
if (ret)
diff --git a/include/linux/mfd/stm32-timers.h b/include/linux/mfd/stm32-timers.h
index d0300045f04a..4a0abbc10ef6 100644
--- a/include/linux/mfd/stm32-timers.h
+++ b/include/linux/mfd/stm32-timers.h
@@ -21,6 +21,7 @@
#define TIM_CCMR1 0x18 /* Capt/Comp 1 Mode Reg */
#define TIM_CCMR2 0x1C /* Capt/Comp 2 Mode Reg */
#define TIM_CCER 0x20 /* Capt/Comp Enable Reg */
+#define TIM_CNT 0x24 /* Counter */
#define TIM_PSC 0x28 /* Prescaler */
#define TIM_ARR 0x2c /* Auto-Reload Register */
#define TIM_CCR1 0x34 /* Capt/Comp Register 1 */
@@ -30,6 +31,7 @@
#define TIM_BDTR 0x44 /* Break and Dead-Time Reg */
#define TIM_CR1_CEN BIT(0) /* Counter Enable */
+#define TIM_CR1_DIR BIT(4) /* Counter Direction */
#define TIM_CR1_ARPE BIT(7) /* Auto-reload Preload Ena */
#define TIM_CR2_MMS (BIT(4) | BIT(5) | BIT(6)) /* Master mode selection */
#define TIM_SMCR_SMS (BIT(0) | BIT(1) | BIT(2)) /* Slave mode selection */