*/
#include <linux/bitfield.h>
+#include <linux/counter.h>
#include <linux/iio/iio.h>
#include <linux/mfd/stm32-lptimer.h>
#include <linux/module.h>
#include <linux/platform_device.h>
struct stm32_lptim_cnt {
+ struct counter_device counter;
struct device *dev;
struct regmap *regmap;
struct clk *clk;
- u32 preset;
+ u32 ceiling;
u32 polarity;
u32 quadrature_mode;
bool enabled;
}
/* LP timer must be enabled before writing CMP & ARR */
- ret = regmap_write(priv->regmap, STM32_LPTIM_ARR, priv->preset);
+ ret = regmap_write(priv->regmap, STM32_LPTIM_ARR, priv->ceiling);
if (ret)
return ret;
.set = stm32_lptim_cnt_set_polarity,
};
-static ssize_t stm32_lptim_cnt_get_preset(struct iio_dev *indio_dev,
- uintptr_t private,
- const struct iio_chan_spec *chan,
- char *buf)
+static ssize_t stm32_lptim_cnt_get_ceiling(struct stm32_lptim_cnt *priv,
+ char *buf)
{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
-
- return snprintf(buf, PAGE_SIZE, "%u\n", priv->preset);
+ return snprintf(buf, PAGE_SIZE, "%u\n", priv->ceiling);
}
-static ssize_t stm32_lptim_cnt_set_preset(struct iio_dev *indio_dev,
- uintptr_t private,
- const struct iio_chan_spec *chan,
- const char *buf, size_t len)
+static ssize_t stm32_lptim_cnt_set_ceiling(struct stm32_lptim_cnt *priv,
+ const char *buf, size_t len)
{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
int ret;
if (stm32_lptim_is_enabled(priv))
return -EBUSY;
- ret = kstrtouint(buf, 0, &priv->preset);
+ ret = kstrtouint(buf, 0, &priv->ceiling);
if (ret)
return ret;
- if (priv->preset > STM32_LPTIM_MAX_ARR)
+ if (priv->ceiling > STM32_LPTIM_MAX_ARR)
return -EINVAL;
return len;
}
+static ssize_t stm32_lptim_cnt_get_preset_iio(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ char *buf)
+{
+ struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
+
+ return stm32_lptim_cnt_get_ceiling(priv, buf);
+}
+
+static ssize_t stm32_lptim_cnt_set_preset_iio(struct iio_dev *indio_dev,
+ uintptr_t private,
+ const struct iio_chan_spec *chan,
+ const char *buf, size_t len)
+{
+ struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
+
+ return stm32_lptim_cnt_set_ceiling(priv, buf, len);
+}
+
/* LP timer with encoder */
static const struct iio_chan_spec_ext_info stm32_lptim_enc_ext_info[] = {
{
.name = "preset",
.shared = IIO_SEPARATE,
- .read = stm32_lptim_cnt_get_preset,
- .write = stm32_lptim_cnt_set_preset,
+ .read = stm32_lptim_cnt_get_preset_iio,
+ .write = stm32_lptim_cnt_set_preset_iio,
},
IIO_ENUM("polarity", IIO_SEPARATE, &stm32_lptim_cnt_polarity_en),
IIO_ENUM_AVAILABLE("polarity", &stm32_lptim_cnt_polarity_en),
{
.name = "preset",
.shared = IIO_SEPARATE,
- .read = stm32_lptim_cnt_get_preset,
- .write = stm32_lptim_cnt_set_preset,
+ .read = stm32_lptim_cnt_get_preset_iio,
+ .write = stm32_lptim_cnt_set_preset_iio,
},
IIO_ENUM("polarity", IIO_SEPARATE, &stm32_lptim_cnt_polarity_en),
IIO_ENUM_AVAILABLE("polarity", &stm32_lptim_cnt_polarity_en),
.indexed = 1,
};
+/**
+ * stm32_lptim_cnt_function - enumerates stm32 LPTimer counter & encoder modes
+ * @STM32_LPTIM_COUNTER_INCREASE: up count on IN1 rising, falling or both edges
+ * @STM32_LPTIM_ENCODER_BOTH_EDGE: count on both edges (IN1 & IN2 quadrature)
+ */
+enum stm32_lptim_cnt_function {
+ STM32_LPTIM_COUNTER_INCREASE,
+ STM32_LPTIM_ENCODER_BOTH_EDGE,
+};
+
+static enum counter_count_function stm32_lptim_cnt_functions[] = {
+ [STM32_LPTIM_COUNTER_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE,
+ [STM32_LPTIM_ENCODER_BOTH_EDGE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
+};
+
+enum stm32_lptim_synapse_action {
+ STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE,
+ STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE,
+ STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES,
+ STM32_LPTIM_SYNAPSE_ACTION_NONE,
+};
+
+static enum counter_synapse_action stm32_lptim_cnt_synapse_actions[] = {
+ /* Index must match with stm32_lptim_cnt_polarity[] (priv->polarity) */
+ [STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+ [STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
+ [STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
+ [STM32_LPTIM_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
+};
+
+static int stm32_lptim_cnt_read(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_count_read_value *val)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+ u32 cnt;
+ int ret;
+
+ ret = regmap_read(priv->regmap, STM32_LPTIM_CNT, &cnt);
+ if (ret)
+ return ret;
+
+ counter_count_read_value_set(val, COUNTER_COUNT_POSITION, &cnt);
+
+ return 0;
+}
+
+static int stm32_lptim_cnt_function_get(struct counter_device *counter,
+ struct counter_count *count,
+ size_t *function)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+
+ if (!priv->quadrature_mode) {
+ *function = STM32_LPTIM_COUNTER_INCREASE;
+ return 0;
+ }
+
+ if (priv->polarity == STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES) {
+ *function = STM32_LPTIM_ENCODER_BOTH_EDGE;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int stm32_lptim_cnt_function_set(struct counter_device *counter,
+ struct counter_count *count,
+ size_t function)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+
+ if (stm32_lptim_is_enabled(priv))
+ return -EBUSY;
+
+ switch (function) {
+ case STM32_LPTIM_COUNTER_INCREASE:
+ priv->quadrature_mode = 0;
+ return 0;
+ case STM32_LPTIM_ENCODER_BOTH_EDGE:
+ priv->quadrature_mode = 1;
+ priv->polarity = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter,
+ struct counter_count *count,
+ void *private, char *buf)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+ int ret;
+
+ ret = stm32_lptim_is_enabled(priv);
+ if (ret < 0)
+ return ret;
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", ret);
+}
+
+static ssize_t stm32_lptim_cnt_enable_write(struct counter_device *counter,
+ struct counter_count *count,
+ void *private,
+ const char *buf, size_t len)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+ bool enable;
+ int ret;
+
+ ret = kstrtobool(buf, &enable);
+ if (ret)
+ return ret;
+
+ /* Check nobody uses the timer, or already disabled/enabled */
+ ret = stm32_lptim_is_enabled(priv);
+ if ((ret < 0) || (!ret && !enable))
+ return ret;
+ if (enable && ret)
+ return -EBUSY;
+
+ ret = stm32_lptim_setup(priv, enable);
+ if (ret)
+ return ret;
+
+ ret = stm32_lptim_set_enable_state(priv, enable);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static ssize_t stm32_lptim_cnt_ceiling_read(struct counter_device *counter,
+ struct counter_count *count,
+ void *private, char *buf)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+
+ return stm32_lptim_cnt_get_ceiling(priv, buf);
+}
+
+static ssize_t stm32_lptim_cnt_ceiling_write(struct counter_device *counter,
+ struct counter_count *count,
+ void *private,
+ const char *buf, size_t len)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+
+ return stm32_lptim_cnt_set_ceiling(priv, buf, len);
+}
+
+static const struct counter_count_ext stm32_lptim_cnt_ext[] = {
+ {
+ .name = "enable",
+ .read = stm32_lptim_cnt_enable_read,
+ .write = stm32_lptim_cnt_enable_write
+ },
+ {
+ .name = "ceiling",
+ .read = stm32_lptim_cnt_ceiling_read,
+ .write = stm32_lptim_cnt_ceiling_write
+ },
+};
+
+static int stm32_lptim_cnt_action_get(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse,
+ size_t *action)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+ size_t function;
+ int err;
+
+ err = stm32_lptim_cnt_function_get(counter, count, &function);
+ if (err)
+ return err;
+
+ switch (function) {
+ case STM32_LPTIM_COUNTER_INCREASE:
+ /* LP Timer acts as up-counter on input 1 */
+ if (synapse->signal->id == count->synapses[0].signal->id)
+ *action = priv->polarity;
+ else
+ *action = STM32_LPTIM_SYNAPSE_ACTION_NONE;
+ return 0;
+ case STM32_LPTIM_ENCODER_BOTH_EDGE:
+ *action = priv->polarity;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static int stm32_lptim_cnt_action_set(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse,
+ size_t action)
+{
+ struct stm32_lptim_cnt *const priv = counter->priv;
+ size_t function;
+ int err;
+
+ if (stm32_lptim_is_enabled(priv))
+ return -EBUSY;
+
+ err = stm32_lptim_cnt_function_get(counter, count, &function);
+ if (err)
+ return err;
+
+ /* only set polarity when in counter mode (on input 1) */
+ if (function == STM32_LPTIM_COUNTER_INCREASE
+ && synapse->signal->id == count->synapses[0].signal->id) {
+ switch (action) {
+ case STM32_LPTIM_SYNAPSE_ACTION_RISING_EDGE:
+ case STM32_LPTIM_SYNAPSE_ACTION_FALLING_EDGE:
+ case STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES:
+ priv->polarity = action;
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static const struct counter_ops stm32_lptim_cnt_ops = {
+ .count_read = stm32_lptim_cnt_read,
+ .function_get = stm32_lptim_cnt_function_get,
+ .function_set = stm32_lptim_cnt_function_set,
+ .action_get = stm32_lptim_cnt_action_get,
+ .action_set = stm32_lptim_cnt_action_set,
+};
+
+static struct counter_signal stm32_lptim_cnt_signals[] = {
+ {
+ .id = 0,
+ .name = "Channel 1 Quadrature A"
+ },
+ {
+ .id = 1,
+ .name = "Channel 1 Quadrature B"
+ }
+};
+
+static struct counter_synapse stm32_lptim_cnt_synapses[] = {
+ {
+ .actions_list = stm32_lptim_cnt_synapse_actions,
+ .num_actions = ARRAY_SIZE(stm32_lptim_cnt_synapse_actions),
+ .signal = &stm32_lptim_cnt_signals[0]
+ },
+ {
+ .actions_list = stm32_lptim_cnt_synapse_actions,
+ .num_actions = ARRAY_SIZE(stm32_lptim_cnt_synapse_actions),
+ .signal = &stm32_lptim_cnt_signals[1]
+ }
+};
+
+/* LP timer with encoder */
+static struct counter_count stm32_lptim_enc_counts = {
+ .id = 0,
+ .name = "LPTimer Count",
+ .functions_list = stm32_lptim_cnt_functions,
+ .num_functions = ARRAY_SIZE(stm32_lptim_cnt_functions),
+ .synapses = stm32_lptim_cnt_synapses,
+ .num_synapses = ARRAY_SIZE(stm32_lptim_cnt_synapses),
+ .ext = stm32_lptim_cnt_ext,
+ .num_ext = ARRAY_SIZE(stm32_lptim_cnt_ext)
+};
+
+/* LP timer without encoder (counter only) */
+static struct counter_count stm32_lptim_in1_counts = {
+ .id = 0,
+ .name = "LPTimer Count",
+ .functions_list = stm32_lptim_cnt_functions,
+ .num_functions = 1,
+ .synapses = stm32_lptim_cnt_synapses,
+ .num_synapses = 1,
+ .ext = stm32_lptim_cnt_ext,
+ .num_ext = ARRAY_SIZE(stm32_lptim_cnt_ext)
+};
+
static int stm32_lptim_cnt_probe(struct platform_device *pdev)
{
struct stm32_lptimer *ddata = dev_get_drvdata(pdev->dev.parent);
struct stm32_lptim_cnt *priv;
struct iio_dev *indio_dev;
+ int ret;
if (IS_ERR_OR_NULL(ddata))
return -EINVAL;
priv->dev = &pdev->dev;
priv->regmap = ddata->regmap;
priv->clk = ddata->clk;
- priv->preset = STM32_LPTIM_MAX_ARR;
+ priv->ceiling = STM32_LPTIM_MAX_ARR;
+ /* Initialize IIO device */
indio_dev->name = dev_name(&pdev->dev);
indio_dev->dev.parent = &pdev->dev;
indio_dev->dev.of_node = pdev->dev.of_node;
indio_dev->channels = &stm32_lptim_cnt_channels;
indio_dev->num_channels = 1;
+ /* Initialize Counter device */
+ priv->counter.name = dev_name(&pdev->dev);
+ priv->counter.parent = &pdev->dev;
+ priv->counter.ops = &stm32_lptim_cnt_ops;
+ if (ddata->has_encoder) {
+ priv->counter.counts = &stm32_lptim_enc_counts;
+ priv->counter.num_signals = ARRAY_SIZE(stm32_lptim_cnt_signals);
+ } else {
+ priv->counter.counts = &stm32_lptim_in1_counts;
+ priv->counter.num_signals = 1;
+ }
+ priv->counter.num_counts = 1;
+ priv->counter.signals = stm32_lptim_cnt_signals;
+ priv->counter.priv = priv;
+
platform_set_drvdata(pdev, priv);
- return devm_iio_device_register(&pdev->dev, indio_dev);
+ ret = devm_iio_device_register(&pdev->dev, indio_dev);
+ if (ret)
+ return ret;
+
+ return devm_counter_register(&pdev->dev, &priv->counter);
}
#ifdef CONFIG_PM_SLEEP
projects / platform / kernel / linux-starfive.git / commitdiff