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path: root/drivers/counter/stm32-lptimer-cnt.c
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Diffstat (limited to 'drivers/counter/stm32-lptimer-cnt.c')
-rw-r--r--drivers/counter/stm32-lptimer-cnt.c297
1 files changed, 36 insertions, 261 deletions
diff --git a/drivers/counter/stm32-lptimer-cnt.c b/drivers/counter/stm32-lptimer-cnt.c
index fd6828e2d34f..937439635d53 100644
--- a/drivers/counter/stm32-lptimer-cnt.c
+++ b/drivers/counter/stm32-lptimer-cnt.c
@@ -12,8 +12,8 @@
#include <linux/bitfield.h>
#include <linux/counter.h>
-#include <linux/iio/iio.h>
#include <linux/mfd/stm32-lptimer.h>
+#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
@@ -107,249 +107,27 @@ static int stm32_lptim_setup(struct stm32_lptim_cnt *priv, int enable)
return regmap_update_bits(priv->regmap, STM32_LPTIM_CFGR, mask, val);
}
-static int stm32_lptim_write_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int val, int val2, long mask)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
- int ret;
-
- switch (mask) {
- case IIO_CHAN_INFO_ENABLE:
- if (val < 0 || val > 1)
- return -EINVAL;
-
- /* Check nobody uses the timer, or already disabled/enabled */
- ret = stm32_lptim_is_enabled(priv);
- if ((ret < 0) || (!ret && !val))
- return ret;
- if (val && ret)
- return -EBUSY;
-
- ret = stm32_lptim_setup(priv, val);
- if (ret)
- return ret;
- return stm32_lptim_set_enable_state(priv, val);
-
- default:
- return -EINVAL;
- }
-}
-
-static int stm32_lptim_read_raw(struct iio_dev *indio_dev,
- struct iio_chan_spec const *chan,
- int *val, int *val2, long mask)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
- u32 dat;
- int ret;
-
- switch (mask) {
- case IIO_CHAN_INFO_RAW:
- ret = regmap_read(priv->regmap, STM32_LPTIM_CNT, &dat);
- if (ret)
- return ret;
- *val = dat;
- return IIO_VAL_INT;
-
- case IIO_CHAN_INFO_ENABLE:
- ret = stm32_lptim_is_enabled(priv);
- if (ret < 0)
- return ret;
- *val = ret;
- return IIO_VAL_INT;
-
- case IIO_CHAN_INFO_SCALE:
- /* Non-quadrature mode: scale = 1 */
- *val = 1;
- *val2 = 0;
- if (priv->quadrature_mode) {
- /*
- * Quadrature encoder mode:
- * - both edges, quarter cycle, scale is 0.25
- * - either rising/falling edge scale is 0.5
- */
- if (priv->polarity > 1)
- *val2 = 2;
- else
- *val2 = 1;
- }
- return IIO_VAL_FRACTIONAL_LOG2;
-
- default:
- return -EINVAL;
- }
-}
-
-static const struct iio_info stm32_lptim_cnt_iio_info = {
- .read_raw = stm32_lptim_read_raw,
- .write_raw = stm32_lptim_write_raw,
-};
-
-static const char *const stm32_lptim_quadrature_modes[] = {
- "non-quadrature",
- "quadrature",
-};
-
-static int stm32_lptim_get_quadrature_mode(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
-
- return priv->quadrature_mode;
-}
-
-static int stm32_lptim_set_quadrature_mode(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan,
- unsigned int type)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
-
- if (stm32_lptim_is_enabled(priv))
- return -EBUSY;
-
- priv->quadrature_mode = type;
-
- return 0;
-}
-
-static const struct iio_enum stm32_lptim_quadrature_mode_en = {
- .items = stm32_lptim_quadrature_modes,
- .num_items = ARRAY_SIZE(stm32_lptim_quadrature_modes),
- .get = stm32_lptim_get_quadrature_mode,
- .set = stm32_lptim_set_quadrature_mode,
-};
-
-static const char * const stm32_lptim_cnt_polarity[] = {
- "rising-edge", "falling-edge", "both-edges",
-};
-
-static int stm32_lptim_cnt_get_polarity(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
-
- return priv->polarity;
-}
-
-static int stm32_lptim_cnt_set_polarity(struct iio_dev *indio_dev,
- const struct iio_chan_spec *chan,
- unsigned int type)
-{
- struct stm32_lptim_cnt *priv = iio_priv(indio_dev);
-
- if (stm32_lptim_is_enabled(priv))
- return -EBUSY;
-
- priv->polarity = type;
-
- return 0;
-}
-
-static const struct iio_enum stm32_lptim_cnt_polarity_en = {
- .items = stm32_lptim_cnt_polarity,
- .num_items = ARRAY_SIZE(stm32_lptim_cnt_polarity),
- .get = stm32_lptim_cnt_get_polarity,
- .set = stm32_lptim_cnt_set_polarity,
-};
-
-static ssize_t stm32_lptim_cnt_get_ceiling(struct stm32_lptim_cnt *priv,
- char *buf)
-{
- return snprintf(buf, PAGE_SIZE, "%u\n", priv->ceiling);
-}
-
-static ssize_t stm32_lptim_cnt_set_ceiling(struct stm32_lptim_cnt *priv,
- const char *buf, size_t len)
-{
- int ret;
-
- if (stm32_lptim_is_enabled(priv))
- return -EBUSY;
-
- ret = kstrtouint(buf, 0, &priv->ceiling);
- if (ret)
- return ret;
-
- 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_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),
- IIO_ENUM("quadrature_mode", IIO_SEPARATE,
- &stm32_lptim_quadrature_mode_en),
- IIO_ENUM_AVAILABLE("quadrature_mode", &stm32_lptim_quadrature_mode_en),
- {}
-};
-
-static const struct iio_chan_spec stm32_lptim_enc_channels = {
- .type = IIO_COUNT,
- .channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_ENABLE) |
- BIT(IIO_CHAN_INFO_SCALE),
- .ext_info = stm32_lptim_enc_ext_info,
- .indexed = 1,
-};
-
-/* LP timer without encoder (counter only) */
-static const struct iio_chan_spec_ext_info stm32_lptim_cnt_ext_info[] = {
- {
- .name = "preset",
- .shared = IIO_SEPARATE,
- .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),
- {}
-};
-
-static const struct iio_chan_spec stm32_lptim_cnt_channels = {
- .type = IIO_COUNT,
- .channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
- BIT(IIO_CHAN_INFO_ENABLE) |
- BIT(IIO_CHAN_INFO_SCALE),
- .ext_info = stm32_lptim_cnt_ext_info,
- .indexed = 1,
-};
-
/**
* enum stm32_lptim_cnt_function - enumerates 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)
+ *
+ * In non-quadrature mode, device counts up on active edge.
+ * In quadrature mode, encoder counting scenarios are as follows:
+ * +---------+----------+--------------------+--------------------+
+ * | Active | Level on | IN1 signal | IN2 signal |
+ * | edge | opposite +----------+---------+----------+---------+
+ * | | signal | Rising | Falling | Rising | Falling |
+ * +---------+----------+----------+---------+----------+---------+
+ * | Rising | High -> | Down | - | Up | - |
+ * | edge | Low -> | Up | - | Down | - |
+ * +---------+----------+----------+---------+----------+---------+
+ * | Falling | High -> | - | Up | - | Down |
+ * | edge | Low -> | - | Down | - | Up |
+ * +---------+----------+----------+---------+----------+---------+
+ * | Both | High -> | Down | Up | Up | Down |
+ * | edges | Low -> | Up | Down | Down | Up |
+ * +---------+----------+----------+---------+----------+---------+
*/
enum stm32_lptim_cnt_function {
STM32_LPTIM_COUNTER_INCREASE,
@@ -484,7 +262,7 @@ static ssize_t stm32_lptim_cnt_ceiling_read(struct counter_device *counter,
{
struct stm32_lptim_cnt *const priv = counter->priv;
- return stm32_lptim_cnt_get_ceiling(priv, buf);
+ return snprintf(buf, PAGE_SIZE, "%u\n", priv->ceiling);
}
static ssize_t stm32_lptim_cnt_ceiling_write(struct counter_device *counter,
@@ -493,8 +271,22 @@ static ssize_t stm32_lptim_cnt_ceiling_write(struct counter_device *counter,
const char *buf, size_t len)
{
struct stm32_lptim_cnt *const priv = counter->priv;
+ unsigned int ceiling;
+ int ret;
+
+ if (stm32_lptim_is_enabled(priv))
+ return -EBUSY;
+
+ ret = kstrtouint(buf, 0, &ceiling);
+ if (ret)
+ return ret;
+
+ if (ceiling > STM32_LPTIM_MAX_ARR)
+ return -EINVAL;
+
+ priv->ceiling = ceiling;
- return stm32_lptim_cnt_set_ceiling(priv, buf, len);
+ return len;
}
static const struct counter_count_ext stm32_lptim_cnt_ext[] = {
@@ -630,32 +422,19 @@ 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;
- indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
- if (!indio_dev)
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
return -ENOMEM;
- priv = iio_priv(indio_dev);
priv->dev = &pdev->dev;
priv->regmap = ddata->regmap;
priv->clk = ddata->clk;
priv->ceiling = STM32_LPTIM_MAX_ARR;
- /* Initialize IIO device */
- indio_dev->name = dev_name(&pdev->dev);
- indio_dev->dev.of_node = pdev->dev.of_node;
- indio_dev->info = &stm32_lptim_cnt_iio_info;
- if (ddata->has_encoder)
- indio_dev->channels = &stm32_lptim_enc_channels;
- else
- 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;
@@ -673,10 +452,6 @@ static int stm32_lptim_cnt_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, priv);
- ret = devm_iio_device_register(&pdev->dev, indio_dev);
- if (ret)
- return ret;
-
return devm_counter_register(&pdev->dev, &priv->counter);
}