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Diffstat (limited to 'drivers/iio/counter/stm32-lptimer-cnt.c')
-rw-r--r--drivers/iio/counter/stm32-lptimer-cnt.c382
1 files changed, 0 insertions, 382 deletions
diff --git a/drivers/iio/counter/stm32-lptimer-cnt.c b/drivers/iio/counter/stm32-lptimer-cnt.c
deleted file mode 100644
index 42fb8ba67090..000000000000
--- a/drivers/iio/counter/stm32-lptimer-cnt.c
+++ /dev/null
@@ -1,382 +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/platform_device.h>
-
-struct stm32_lptim_cnt {
- struct device *dev;
- struct regmap *regmap;
- struct clk *clk;
- u32 preset;
- u32 polarity;
- u32 quadrature_mode;
-};
-
-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);
- 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;
- }
-
- /* 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);
-}
-
-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,
- },
-};
-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");