counter: stm32-lptimer: add counter device

Add support for new counter device to stm32-lptimer.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

5 files changed, 0 insertions, 463 deletions

diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig
index 014006d1cbb6..4243e35c25e9 100644
--- a/drivers/iio/Kconfig
+++ b/drivers/iio/Kconfig
@@ -74,7 +74,6 @@ source "drivers/iio/afe/Kconfig"
 source "drivers/iio/amplifiers/Kconfig"
 source "drivers/iio/chemical/Kconfig"
 source "drivers/iio/common/Kconfig"
-source "drivers/iio/counter/Kconfig"
 source "drivers/iio/dac/Kconfig"
 source "drivers/iio/dummy/Kconfig"
 source "drivers/iio/frequency/Kconfig"
diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile
index cb5993251381..bff682ad1cfb 100644
--- a/drivers/iio/Makefile
+++ b/drivers/iio/Makefile
@@ -20,7 +20,6 @@ obj-y += amplifiers/
 obj-y += buffer/
 obj-y += chemical/
 obj-y += common/
-obj-y += counter/
 obj-y += dac/
 obj-y += dummy/
 obj-y += gyro/
diff --git a/drivers/iio/counter/Kconfig b/drivers/iio/counter/Kconfig
deleted file mode 100644
index eeb358122cbe..000000000000
--- a/drivers/iio/counter/Kconfig
+++ /dev/null
@@ -1,17 +0,0 @@
-#
-# Counter devices
-#
-# When adding new entries keep the list in alphabetical order
-
-menu "Counters"
-
-config STM32_LPTIMER_CNT
-	tristate "STM32 LP Timer encoder counter driver"
-	depends on MFD_STM32_LPTIMER || COMPILE_TEST
-	help
-	  Select this option to enable STM32 Low-Power Timer quadrature encoder
-	  and counter driver.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called stm32-lptimer-cnt.
-endmenu
diff --git a/drivers/iio/counter/Makefile b/drivers/iio/counter/Makefile
deleted file mode 100644
index 93933ba49280..000000000000
--- a/drivers/iio/counter/Makefile
+++ /dev/null
@@ -1,7 +0,0 @@
-#
-# Makefile for IIO counter devices
-#
-
-# When adding new entries keep the list in alphabetical order
-
-obj-$(CONFIG_STM32_LPTIMER_CNT)	+= stm32-lptimer-cnt.o
diff --git a/drivers/iio/counter/stm32-lptimer-cnt.c b/drivers/iio/counter/stm32-lptimer-cnt.c
deleted file mode 100644
index 2a49cce0edb4..000000000000
--- a/drivers/iio/counter/stm32-lptimer-cnt.c
+++ /dev/null
@@ -1,437 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * STM32 Low-Power Timer Encoder and Counter driver
- *
- * Copyright (C) STMicroelectronics 2017
- *
- * Author: Fabrice Gasnier <fabrice.gasnier@st.com>
- *
- * Inspired by 104-quad-8 and stm32-timer-trigger drivers.
- *
- */
-
-#include <linux/bitfield.h>
-#include <linux/iio/iio.h>
-#include <linux/mfd/stm32-lptimer.h>
-#include <linux/module.h>
-#include <linux/pinctrl/consumer.h>
-#include <linux/platform_device.h>
-
-struct stm32_lptim_cnt {
-	struct device *dev;
-	struct regmap *regmap;
-	struct clk *clk;
-	u32 preset;
-	u32 polarity;
-	u32 quadrature_mode;
-	bool enabled;
-};
-
-static int stm32_lptim_is_enabled(struct stm32_lptim_cnt *priv)
-{
-	u32 val;
-	int ret;
-
-	ret = regmap_read(priv->regmap, STM32_LPTIM_CR, &val);
-	if (ret)
-		return ret;
-
-	return FIELD_GET(STM32_LPTIM_ENABLE, val);
-}
-
-static int stm32_lptim_set_enable_state(struct stm32_lptim_cnt *priv,
-					int enable)
-{
-	int ret;
-	u32 val;
-
-	val = FIELD_PREP(STM32_LPTIM_ENABLE, enable);
-	ret = regmap_write(priv->regmap, STM32_LPTIM_CR, val);
-	if (ret)
-		return ret;
-
-	if (!enable) {
-		clk_disable(priv->clk);
-		priv->enabled = false;
-		return 0;
-	}
-
-	/* LP timer must be enabled before writing CMP & ARR */
-	ret = regmap_write(priv->regmap, STM32_LPTIM_ARR, priv->preset);
-	if (ret)
-		return ret;
-
-	ret = regmap_write(priv->regmap, STM32_LPTIM_CMP, 0);
-	if (ret)
-		return ret;
-
-	/* ensure CMP & ARR registers are properly written */
-	ret = regmap_read_poll_timeout(priv->regmap, STM32_LPTIM_ISR, val,
-				       (val & STM32_LPTIM_CMPOK_ARROK),
-				       100, 1000);
-	if (ret)
-		return ret;
-
-	ret = regmap_write(priv->regmap, STM32_LPTIM_ICR,
-			   STM32_LPTIM_CMPOKCF_ARROKCF);
-	if (ret)
-		return ret;
-
-	ret = clk_enable(priv->clk);
-	if (ret) {
-		regmap_write(priv->regmap, STM32_LPTIM_CR, 0);
-		return ret;
-	}
-	priv->enabled = true;
-
-	/* Start LP timer in continuous mode */
-	return regmap_update_bits(priv->regmap, STM32_LPTIM_CR,
-				  STM32_LPTIM_CNTSTRT, STM32_LPTIM_CNTSTRT);
-}
-
-static int stm32_lptim_setup(struct stm32_lptim_cnt *priv, int enable)
-{
-	u32 mask = STM32_LPTIM_ENC | STM32_LPTIM_COUNTMODE |
-		   STM32_LPTIM_CKPOL | STM32_LPTIM_PRESC;
-	u32 val;
-
-	/* Setup LP timer encoder/counter and polarity, without prescaler */
-	if (priv->quadrature_mode)
-		val = enable ? STM32_LPTIM_ENC : 0;
-	else
-		val = enable ? STM32_LPTIM_COUNTMODE : 0;
-	val |= FIELD_PREP(STM32_LPTIM_CKPOL, enable ? priv->polarity : 0);
-
-	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_preset(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 snprintf(buf, PAGE_SIZE, "%u\n", priv->preset);
-}
-
-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)
-{
-	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);
-	if (ret)
-		return ret;
-
-	if (priv->preset > STM32_LPTIM_MAX_ARR)
-		return -EINVAL;
-
-	return 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,
-	},
-	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,
-		.write = stm32_lptim_cnt_set_preset,
-	},
-	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,
-};
-
-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;
-
-	if (IS_ERR_OR_NULL(ddata))
-		return -EINVAL;
-
-	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*priv));
-	if (!indio_dev)
-		return -ENOMEM;
-
-	priv = iio_priv(indio_dev);
-	priv->dev = &pdev->dev;
-	priv->regmap = ddata->regmap;
-	priv->clk = ddata->clk;
-	priv->preset = STM32_LPTIM_MAX_ARR;
-
-	indio_dev->name = dev_name(&pdev->dev);
-	indio_dev->dev.parent = &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;
-
-	platform_set_drvdata(pdev, priv);
-
-	return devm_iio_device_register(&pdev->dev, indio_dev);
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int stm32_lptim_cnt_suspend(struct device *dev)
-{
-	struct stm32_lptim_cnt *priv = dev_get_drvdata(dev);
-	int ret;
-
-	/* Only take care of enabled counter: don't disturb other MFD child */
-	if (priv->enabled) {
-		ret = stm32_lptim_setup(priv, 0);
-		if (ret)
-			return ret;
-
-		ret = stm32_lptim_set_enable_state(priv, 0);
-		if (ret)
-			return ret;
-
-		/* Force enable state for later resume */
-		priv->enabled = true;
-	}
-
-	return pinctrl_pm_select_sleep_state(dev);
-}
-
-static int stm32_lptim_cnt_resume(struct device *dev)
-{
-	struct stm32_lptim_cnt *priv = dev_get_drvdata(dev);
-	int ret;
-
-	ret = pinctrl_pm_select_default_state(dev);
-	if (ret)
-		return ret;
-
-	if (priv->enabled) {
-		priv->enabled = false;
-		ret = stm32_lptim_setup(priv, 1);
-		if (ret)
-			return ret;
-
-		ret = stm32_lptim_set_enable_state(priv, 1);
-		if (ret)
-			return ret;
-	}
-
-	return 0;
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(stm32_lptim_cnt_pm_ops, stm32_lptim_cnt_suspend,
-			 stm32_lptim_cnt_resume);
-
-static const struct of_device_id stm32_lptim_cnt_of_match[] = {
-	{ .compatible = "st,stm32-lptimer-counter", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, stm32_lptim_cnt_of_match);
-
-static struct platform_driver stm32_lptim_cnt_driver = {
-	.probe = stm32_lptim_cnt_probe,
-	.driver = {
-		.name = "stm32-lptimer-counter",
-		.of_match_table = stm32_lptim_cnt_of_match,
-		.pm = &stm32_lptim_cnt_pm_ops,
-	},
-};
-module_platform_driver(stm32_lptim_cnt_driver);
-
-MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
-MODULE_ALIAS("platform:stm32-lptimer-counter");
-MODULE_DESCRIPTION("STMicroelectronics STM32 LPTIM counter driver");
-MODULE_LICENSE("GPL v2");