drivers/counter/microchip-tcb-capture.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /**
  * Copyright (C) 2020 Microchip
  *
  * Author: Kamel Bouhara <kamel.bouhara@bootlin.com>
  */
 #include <linux/clk.h>
 #include <linux/counter.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <soc/at91/atmel_tcb.h>

 #define ATMEL_TC_CMR_MASK	(ATMEL_TC_LDRA_RISING | ATMEL_TC_LDRB_FALLING | \
 				 ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_LDBDIS | \
 				 ATMEL_TC_LDBSTOP)

 #define ATMEL_TC_QDEN			BIT(8)
 #define ATMEL_TC_POSEN			BIT(9)

 struct mchp_tc_data {
 	const struct atmel_tcb_config *tc_cfg;
 	struct counter_device counter;
 	struct regmap *regmap;
 	int qdec_mode;
 	int num_channels;
 	int channel[2];
 	bool trig_inverted;
 };

 enum mchp_tc_count_function {
 	MCHP_TC_FUNCTION_INCREASE,
 	MCHP_TC_FUNCTION_QUADRATURE,
 };

 static enum counter_count_function mchp_tc_count_functions[] = {
 	[MCHP_TC_FUNCTION_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE,
 	[MCHP_TC_FUNCTION_QUADRATURE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
 };

 enum mchp_tc_synapse_action {
 	MCHP_TC_SYNAPSE_ACTION_NONE = 0,
 	MCHP_TC_SYNAPSE_ACTION_RISING_EDGE,
 	MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE,
 	MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE
 };

 static enum counter_synapse_action mchp_tc_synapse_actions[] = {
 	[MCHP_TC_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
 	[MCHP_TC_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
 	[MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
 	[MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
 };

 static struct counter_signal mchp_tc_count_signals[] = {
 	{
 		.id = 0,
 		.name = "Channel A",
 	},
 	{
 		.id = 1,
 		.name = "Channel B",
 	}
 };

 static struct counter_synapse mchp_tc_count_synapses[] = {
 	{
 		.actions_list = mchp_tc_synapse_actions,
 		.num_actions = ARRAY_SIZE(mchp_tc_synapse_actions),
 		.signal = &mchp_tc_count_signals[0]
 	},
 	{
 		.actions_list = mchp_tc_synapse_actions,
 		.num_actions = ARRAY_SIZE(mchp_tc_synapse_actions),
 		.signal = &mchp_tc_count_signals[1]
 	}
 };

 static int mchp_tc_count_function_get(struct counter_device *counter,
 				      struct counter_count *count,
 				      size_t *function)
 {
 	struct mchp_tc_data *const priv = counter->priv;

 	if (priv->qdec_mode)
 		*function = MCHP_TC_FUNCTION_QUADRATURE;
 	else
 		*function = MCHP_TC_FUNCTION_INCREASE;

 	return 0;
 }

 static int mchp_tc_count_function_set(struct counter_device *counter,
 				      struct counter_count *count,
 				      size_t function)
 {
 	struct mchp_tc_data *const priv = counter->priv;
 	u32 bmr, cmr;

 	regmap_read(priv->regmap, ATMEL_TC_BMR, &bmr);
 	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr);

 	/* Set capture mode */
 	cmr &= ~ATMEL_TC_WAVE;

 	switch (function) {
 	case MCHP_TC_FUNCTION_INCREASE:
 		priv->qdec_mode = 0;
 		/* Set highest rate based on whether soc has gclk or not */
 		bmr &= ~(ATMEL_TC_QDEN | ATMEL_TC_POSEN);
 		if (priv->tc_cfg->has_gclk)
 			cmr |= ATMEL_TC_TIMER_CLOCK2;
 		else
 			cmr |= ATMEL_TC_TIMER_CLOCK1;
 		/* Setup the period capture mode */
 		cmr |=  ATMEL_TC_CMR_MASK;
 		cmr &= ~(ATMEL_TC_ABETRG | ATMEL_TC_XC0);
 		break;
 	case MCHP_TC_FUNCTION_QUADRATURE:
 		if (!priv->tc_cfg->has_qdec)
 			return -EINVAL;
 		/* In QDEC mode settings both channels 0 and 1 are required */
 		if (priv->num_channels < 2 || priv->channel[0] != 0 ||
 		    priv->channel[1] != 1) {
 			pr_err("Invalid channels number or id for quadrature mode\n");
 			return -EINVAL;
 		}
 		priv->qdec_mode = 1;
 		bmr |= ATMEL_TC_QDEN | ATMEL_TC_POSEN;
 		cmr |= ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_ABETRG | ATMEL_TC_XC0;
 		break;
 	}

 	regmap_write(priv->regmap, ATMEL_TC_BMR, bmr);
 	regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), cmr);

 	/* Enable clock and trigger counter */
 	regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CCR),
 		     ATMEL_TC_CLKEN | ATMEL_TC_SWTRG);

 	if (priv->qdec_mode) {
 		regmap_write(priv->regmap,
 			     ATMEL_TC_REG(priv->channel[1], CMR), cmr);
 		regmap_write(priv->regmap,
 			     ATMEL_TC_REG(priv->channel[1], CCR),
 			     ATMEL_TC_CLKEN | ATMEL_TC_SWTRG);
 	}

 	return 0;
 }

 static int mchp_tc_count_signal_read(struct counter_device *counter,
 				     struct counter_signal *signal,
 				     enum counter_signal_value *val)
 {
 	struct mchp_tc_data *const priv = counter->priv;
 	bool sigstatus;
 	u32 sr;

 	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], SR), &sr);

 	if (priv->trig_inverted)
 		sigstatus = (sr & ATMEL_TC_MTIOB);
 	else
 		sigstatus = (sr & ATMEL_TC_MTIOA);

 	*val = sigstatus ? COUNTER_SIGNAL_HIGH : COUNTER_SIGNAL_LOW;

 	return 0;
 }

 static int mchp_tc_count_action_get(struct counter_device *counter,
 				    struct counter_count *count,
 				    struct counter_synapse *synapse,
 				    size_t *action)
 {
 	struct mchp_tc_data *const priv = counter->priv;
 	u32 cmr;

 	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr);

 	*action = MCHP_TC_SYNAPSE_ACTION_NONE;

 	if (cmr & ATMEL_TC_ETRGEDG_NONE)
 		*action = MCHP_TC_SYNAPSE_ACTION_NONE;
 	else if (cmr & ATMEL_TC_ETRGEDG_RISING)
 		*action = MCHP_TC_SYNAPSE_ACTION_RISING_EDGE;
 	else if (cmr & ATMEL_TC_ETRGEDG_FALLING)
 		*action = MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE;
 	else if (cmr & ATMEL_TC_ETRGEDG_BOTH)
 		*action = MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE;

 	return 0;
 }

 static int mchp_tc_count_action_set(struct counter_device *counter,
 				    struct counter_count *count,
 				    struct counter_synapse *synapse,
 				    size_t action)
 {
 	struct mchp_tc_data *const priv = counter->priv;
 	u32 edge = ATMEL_TC_ETRGEDG_NONE;

 	/* QDEC mode is rising edge only */
 	if (priv->qdec_mode)
 		return -EINVAL;

 	switch (action) {
 	case MCHP_TC_SYNAPSE_ACTION_NONE:
 		edge = ATMEL_TC_ETRGEDG_NONE;
 		break;
 	case MCHP_TC_SYNAPSE_ACTION_RISING_EDGE:
 		edge = ATMEL_TC_ETRGEDG_RISING;
 		break;
 	case MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE:
 		edge = ATMEL_TC_ETRGEDG_FALLING;
 		break;
 	case MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE:
 		edge = ATMEL_TC_ETRGEDG_BOTH;
 		break;
 	}

 	return regmap_write_bits(priv->regmap,
 				ATMEL_TC_REG(priv->channel[0], CMR),
 				ATMEL_TC_ETRGEDG, edge);
 }

 static int mchp_tc_count_read(struct counter_device *counter,
 			      struct counter_count *count,
 			      unsigned long *val)
 {
 	struct mchp_tc_data *const priv = counter->priv;
 	u32 cnt;

 	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CV), &cnt);
 	*val = cnt;

 	return 0;
 }

 static struct counter_count mchp_tc_counts[] = {
 	{
 		.id = 0,
 		.name = "Timer Counter",
 		.functions_list = mchp_tc_count_functions,
 		.num_functions = ARRAY_SIZE(mchp_tc_count_functions),
 		.synapses = mchp_tc_count_synapses,
 		.num_synapses = ARRAY_SIZE(mchp_tc_count_synapses),
 	},
 };

 static struct counter_ops mchp_tc_ops = {
 	.signal_read  = mchp_tc_count_signal_read,
 	.count_read   = mchp_tc_count_read,
 	.function_get = mchp_tc_count_function_get,
 	.function_set = mchp_tc_count_function_set,
 	.action_get   = mchp_tc_count_action_get,
 	.action_set   = mchp_tc_count_action_set
 };

 static const struct atmel_tcb_config tcb_rm9200_config = {
 		.counter_width = 16,
 };

 static const struct atmel_tcb_config tcb_sam9x5_config = {
 		.counter_width = 32,
 };

 static const struct atmel_tcb_config tcb_sama5d2_config = {
 		.counter_width = 32,
 		.has_gclk = true,
 		.has_qdec = true,
 };

 static const struct atmel_tcb_config tcb_sama5d3_config = {
 		.counter_width = 32,
 		.has_qdec = true,
 };

 static const struct of_device_id atmel_tc_of_match[] = {
 	{ .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, },
 	{ .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, },
 	{ .compatible = "atmel,sama5d2-tcb", .data = &tcb_sama5d2_config, },
 	{ .compatible = "atmel,sama5d3-tcb", .data = &tcb_sama5d3_config, },
 	{ /* sentinel */ }
 };

 static void mchp_tc_clk_remove(void *ptr)
 {
 	clk_disable_unprepare((struct clk *)ptr);
 }

 static int mchp_tc_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	const struct atmel_tcb_config *tcb_config;
 	const struct of_device_id *match;
 	struct mchp_tc_data *priv;
 	char clk_name[7];
 	struct regmap *regmap;
 	struct clk *clk[3];
 	int channel;
 	int ret, i;

 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	platform_set_drvdata(pdev, priv);

 	match = of_match_node(atmel_tc_of_match, np->parent);
 	tcb_config = match->data;
 	if (!tcb_config) {
 		dev_err(&pdev->dev, "No matching parent node found\n");
 		return -ENODEV;
 	}

 	regmap = syscon_node_to_regmap(np->parent);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);

 	/* max. channels number is 2 when in QDEC mode */
 	priv->num_channels = of_property_count_u32_elems(np, "reg");
 	if (priv->num_channels < 0) {
 		dev_err(&pdev->dev, "Invalid or missing channel\n");
 		return -EINVAL;
 	}

 	/* Register channels and initialize clocks */
 	for (i = 0; i < priv->num_channels; i++) {
 		ret = of_property_read_u32_index(np, "reg", i, &channel);
 		if (ret < 0 || channel > 2)
 			return -ENODEV;

 		priv->channel[i] = channel;

 		snprintf(clk_name, sizeof(clk_name), "t%d_clk", channel);

 		clk[i] = of_clk_get_by_name(np->parent, clk_name);
 		if (IS_ERR(clk[i])) {
 			/* Fallback to t0_clk */
 			clk[i] = of_clk_get_by_name(np->parent, "t0_clk");
 			if (IS_ERR(clk[i]))
 				return PTR_ERR(clk[i]);
 		}

 		ret = clk_prepare_enable(clk[i]);
 		if (ret)
 			return ret;

 		ret = devm_add_action_or_reset(&pdev->dev,
 					       mchp_tc_clk_remove,
 					       clk[i]);
 		if (ret)
 			return ret;

 		dev_dbg(&pdev->dev,
 			"Initialized capture mode on channel %d\n",
 			channel);
 	}

 	priv->tc_cfg = tcb_config;
 	priv->regmap = regmap;
 	priv->counter.name = dev_name(&pdev->dev);
 	priv->counter.parent = &pdev->dev;
 	priv->counter.ops = &mchp_tc_ops;
 	priv->counter.num_counts = ARRAY_SIZE(mchp_tc_counts);
 	priv->counter.counts = mchp_tc_counts;
 	priv->counter.num_signals = ARRAY_SIZE(mchp_tc_count_signals);
 	priv->counter.signals = mchp_tc_count_signals;
 	priv->counter.priv = priv;

 	return devm_counter_register(&pdev->dev, &priv->counter);
 }

 static const struct of_device_id mchp_tc_dt_ids[] = {
 	{ .compatible = "microchip,tcb-capture", },
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, mchp_tc_dt_ids);

 static struct platform_driver mchp_tc_driver = {
 	.probe = mchp_tc_probe,
 	.driver = {
 		.name = "microchip-tcb-capture",
 		.of_match_table = mchp_tc_dt_ids,
 	},
 };
 module_platform_driver(mchp_tc_driver);

 MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>");
 MODULE_DESCRIPTION("Microchip TCB Capture driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-only
	/**
	* Copyright (C) 2020 Microchip
	*
	* Author: Kamel Bouhara <kamel.bouhara@bootlin.com>
	*/
	#include <linux/clk.h>
	#include <linux/counter.h>
	#include <linux/mfd/syscon.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/of.h>
	#include <linux/of_device.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>
	#include <soc/at91/atmel_tcb.h>

	#define ATMEL_TC_CMR_MASK (ATMEL_TC_LDRA_RISING \| ATMEL_TC_LDRB_FALLING \| \
	ATMEL_TC_ETRGEDG_RISING \| ATMEL_TC_LDBDIS \| \
	ATMEL_TC_LDBSTOP)

	#define ATMEL_TC_QDEN BIT(8)
	#define ATMEL_TC_POSEN BIT(9)

	struct mchp_tc_data {
	const struct atmel_tcb_config *tc_cfg;
	struct counter_device counter;
	struct regmap *regmap;
	int qdec_mode;
	int num_channels;
	int channel[2];
	bool trig_inverted;
	};

	enum mchp_tc_count_function {
	MCHP_TC_FUNCTION_INCREASE,
	MCHP_TC_FUNCTION_QUADRATURE,
	};

	static enum counter_count_function mchp_tc_count_functions[] = {
	[MCHP_TC_FUNCTION_INCREASE] = COUNTER_COUNT_FUNCTION_INCREASE,
	[MCHP_TC_FUNCTION_QUADRATURE] = COUNTER_COUNT_FUNCTION_QUADRATURE_X4,
	};

	enum mchp_tc_synapse_action {
	MCHP_TC_SYNAPSE_ACTION_NONE = 0,
	MCHP_TC_SYNAPSE_ACTION_RISING_EDGE,
	MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE,
	MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE
	};

	static enum counter_synapse_action mchp_tc_synapse_actions[] = {
	[MCHP_TC_SYNAPSE_ACTION_NONE] = COUNTER_SYNAPSE_ACTION_NONE,
	[MCHP_TC_SYNAPSE_ACTION_RISING_EDGE] = COUNTER_SYNAPSE_ACTION_RISING_EDGE,
	[MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE] = COUNTER_SYNAPSE_ACTION_FALLING_EDGE,
	[MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE] = COUNTER_SYNAPSE_ACTION_BOTH_EDGES,
	};

	static struct counter_signal mchp_tc_count_signals[] = {
	{
	.id = 0,
	.name = "Channel A",
	},
	{
	.id = 1,
	.name = "Channel B",
	}
	};

	static struct counter_synapse mchp_tc_count_synapses[] = {
	{
	.actions_list = mchp_tc_synapse_actions,
	.num_actions = ARRAY_SIZE(mchp_tc_synapse_actions),
	.signal = &mchp_tc_count_signals[0]
	},
	{
	.actions_list = mchp_tc_synapse_actions,
	.num_actions = ARRAY_SIZE(mchp_tc_synapse_actions),
	.signal = &mchp_tc_count_signals[1]
	}
	};

	static int mchp_tc_count_function_get(struct counter_device *counter,
	struct counter_count *count,
	size_t *function)
	{
	struct mchp_tc_data *const priv = counter->priv;

	if (priv->qdec_mode)
	*function = MCHP_TC_FUNCTION_QUADRATURE;
	else
	*function = MCHP_TC_FUNCTION_INCREASE;

	return 0;
	}

	static int mchp_tc_count_function_set(struct counter_device *counter,
	struct counter_count *count,
	size_t function)
	{
	struct mchp_tc_data *const priv = counter->priv;
	u32 bmr, cmr;

	regmap_read(priv->regmap, ATMEL_TC_BMR, &bmr);
	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr);

	/* Set capture mode */
	cmr &= ~ATMEL_TC_WAVE;

	switch (function) {
	case MCHP_TC_FUNCTION_INCREASE:
	priv->qdec_mode = 0;
	/* Set highest rate based on whether soc has gclk or not */
	bmr &= ~(ATMEL_TC_QDEN \| ATMEL_TC_POSEN);
	if (priv->tc_cfg->has_gclk)
	cmr \|= ATMEL_TC_TIMER_CLOCK2;
	else
	cmr \|= ATMEL_TC_TIMER_CLOCK1;
	/* Setup the period capture mode */
	cmr \|= ATMEL_TC_CMR_MASK;
	cmr &= ~(ATMEL_TC_ABETRG \| ATMEL_TC_XC0);
	break;
	case MCHP_TC_FUNCTION_QUADRATURE:
	if (!priv->tc_cfg->has_qdec)
	return -EINVAL;
	/* In QDEC mode settings both channels 0 and 1 are required */
	if (priv->num_channels < 2 \|\| priv->channel[0] != 0 \|\|
	priv->channel[1] != 1) {
	pr_err("Invalid channels number or id for quadrature mode\n");
	return -EINVAL;
	}
	priv->qdec_mode = 1;
	bmr \|= ATMEL_TC_QDEN \| ATMEL_TC_POSEN;
	cmr \|= ATMEL_TC_ETRGEDG_RISING \| ATMEL_TC_ABETRG \| ATMEL_TC_XC0;
	break;
	}

	regmap_write(priv->regmap, ATMEL_TC_BMR, bmr);
	regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), cmr);

	/* Enable clock and trigger counter */
	regmap_write(priv->regmap, ATMEL_TC_REG(priv->channel[0], CCR),
	ATMEL_TC_CLKEN \| ATMEL_TC_SWTRG);

	if (priv->qdec_mode) {
	regmap_write(priv->regmap,
	ATMEL_TC_REG(priv->channel[1], CMR), cmr);
	regmap_write(priv->regmap,
	ATMEL_TC_REG(priv->channel[1], CCR),
	ATMEL_TC_CLKEN \| ATMEL_TC_SWTRG);
	}

	return 0;
	}

	static int mchp_tc_count_signal_read(struct counter_device *counter,
	struct counter_signal *signal,
	enum counter_signal_value *val)
	{
	struct mchp_tc_data *const priv = counter->priv;
	bool sigstatus;
	u32 sr;

	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], SR), &sr);

	if (priv->trig_inverted)
	sigstatus = (sr & ATMEL_TC_MTIOB);
	else
	sigstatus = (sr & ATMEL_TC_MTIOA);

	*val = sigstatus ? COUNTER_SIGNAL_HIGH : COUNTER_SIGNAL_LOW;

	return 0;
	}

	static int mchp_tc_count_action_get(struct counter_device *counter,
	struct counter_count *count,
	struct counter_synapse *synapse,
	size_t *action)
	{
	struct mchp_tc_data *const priv = counter->priv;
	u32 cmr;

	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CMR), &cmr);

	*action = MCHP_TC_SYNAPSE_ACTION_NONE;

	if (cmr & ATMEL_TC_ETRGEDG_NONE)
	*action = MCHP_TC_SYNAPSE_ACTION_NONE;
	else if (cmr & ATMEL_TC_ETRGEDG_RISING)
	*action = MCHP_TC_SYNAPSE_ACTION_RISING_EDGE;
	else if (cmr & ATMEL_TC_ETRGEDG_FALLING)
	*action = MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE;
	else if (cmr & ATMEL_TC_ETRGEDG_BOTH)
	*action = MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE;

	return 0;
	}

	static int mchp_tc_count_action_set(struct counter_device *counter,
	struct counter_count *count,
	struct counter_synapse *synapse,
	size_t action)
	{
	struct mchp_tc_data *const priv = counter->priv;
	u32 edge = ATMEL_TC_ETRGEDG_NONE;

	/* QDEC mode is rising edge only */
	if (priv->qdec_mode)
	return -EINVAL;

	switch (action) {
	case MCHP_TC_SYNAPSE_ACTION_NONE:
	edge = ATMEL_TC_ETRGEDG_NONE;
	break;
	case MCHP_TC_SYNAPSE_ACTION_RISING_EDGE:
	edge = ATMEL_TC_ETRGEDG_RISING;
	break;
	case MCHP_TC_SYNAPSE_ACTION_FALLING_EDGE:
	edge = ATMEL_TC_ETRGEDG_FALLING;
	break;
	case MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE:
	edge = ATMEL_TC_ETRGEDG_BOTH;
	break;
	}

	return regmap_write_bits(priv->regmap,
	ATMEL_TC_REG(priv->channel[0], CMR),
	ATMEL_TC_ETRGEDG, edge);
	}

	static int mchp_tc_count_read(struct counter_device *counter,
	struct counter_count *count,
	unsigned long *val)
	{
	struct mchp_tc_data *const priv = counter->priv;
	u32 cnt;

	regmap_read(priv->regmap, ATMEL_TC_REG(priv->channel[0], CV), &cnt);
	*val = cnt;

	return 0;
	}

	static struct counter_count mchp_tc_counts[] = {
	{
	.id = 0,
	.name = "Timer Counter",
	.functions_list = mchp_tc_count_functions,
	.num_functions = ARRAY_SIZE(mchp_tc_count_functions),
	.synapses = mchp_tc_count_synapses,
	.num_synapses = ARRAY_SIZE(mchp_tc_count_synapses),
	},
	};

	static struct counter_ops mchp_tc_ops = {
	.signal_read = mchp_tc_count_signal_read,
	.count_read = mchp_tc_count_read,
	.function_get = mchp_tc_count_function_get,
	.function_set = mchp_tc_count_function_set,
	.action_get = mchp_tc_count_action_get,
	.action_set = mchp_tc_count_action_set
	};

	static const struct atmel_tcb_config tcb_rm9200_config = {
	.counter_width = 16,
	};

	static const struct atmel_tcb_config tcb_sam9x5_config = {
	.counter_width = 32,
	};

	static const struct atmel_tcb_config tcb_sama5d2_config = {
	.counter_width = 32,
	.has_gclk = true,
	.has_qdec = true,
	};

	static const struct atmel_tcb_config tcb_sama5d3_config = {
	.counter_width = 32,
	.has_qdec = true,
	};

	static const struct of_device_id atmel_tc_of_match[] = {
	{ .compatible = "atmel,at91rm9200-tcb", .data = &tcb_rm9200_config, },
	{ .compatible = "atmel,at91sam9x5-tcb", .data = &tcb_sam9x5_config, },
	{ .compatible = "atmel,sama5d2-tcb", .data = &tcb_sama5d2_config, },
	{ .compatible = "atmel,sama5d3-tcb", .data = &tcb_sama5d3_config, },
	{ /* sentinel */ }
	};

	static void mchp_tc_clk_remove(void *ptr)
	{
	clk_disable_unprepare((struct clk *)ptr);
	}

	static int mchp_tc_probe(struct platform_device *pdev)
	{
	struct device_node *np = pdev->dev.of_node;
	const struct atmel_tcb_config *tcb_config;
	const struct of_device_id *match;
	struct mchp_tc_data *priv;
	char clk_name[7];
	struct regmap *regmap;
	struct clk *clk[3];
	int channel;
	int ret, i;

	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	platform_set_drvdata(pdev, priv);

	match = of_match_node(atmel_tc_of_match, np->parent);
	tcb_config = match->data;
	if (!tcb_config) {
	dev_err(&pdev->dev, "No matching parent node found\n");
	return -ENODEV;
	}

	regmap = syscon_node_to_regmap(np->parent);
	if (IS_ERR(regmap))
	return PTR_ERR(regmap);

	/* max. channels number is 2 when in QDEC mode */
	priv->num_channels = of_property_count_u32_elems(np, "reg");
	if (priv->num_channels < 0) {
	dev_err(&pdev->dev, "Invalid or missing channel\n");
	return -EINVAL;
	}

	/* Register channels and initialize clocks */
	for (i = 0; i < priv->num_channels; i++) {
	ret = of_property_read_u32_index(np, "reg", i, &channel);
	if (ret < 0 \|\| channel > 2)
	return -ENODEV;

	priv->channel[i] = channel;

	snprintf(clk_name, sizeof(clk_name), "t%d_clk", channel);

	clk[i] = of_clk_get_by_name(np->parent, clk_name);
	if (IS_ERR(clk[i])) {
	/* Fallback to t0_clk */
	clk[i] = of_clk_get_by_name(np->parent, "t0_clk");
	if (IS_ERR(clk[i]))
	return PTR_ERR(clk[i]);
	}

	ret = clk_prepare_enable(clk[i]);
	if (ret)
	return ret;

	ret = devm_add_action_or_reset(&pdev->dev,
	mchp_tc_clk_remove,
	clk[i]);
	if (ret)
	return ret;

	dev_dbg(&pdev->dev,
	"Initialized capture mode on channel %d\n",
	channel);
	}

	priv->tc_cfg = tcb_config;
	priv->regmap = regmap;
	priv->counter.name = dev_name(&pdev->dev);
	priv->counter.parent = &pdev->dev;
	priv->counter.ops = &mchp_tc_ops;
	priv->counter.num_counts = ARRAY_SIZE(mchp_tc_counts);
	priv->counter.counts = mchp_tc_counts;
	priv->counter.num_signals = ARRAY_SIZE(mchp_tc_count_signals);
	priv->counter.signals = mchp_tc_count_signals;
	priv->counter.priv = priv;

	return devm_counter_register(&pdev->dev, &priv->counter);
	}

	static const struct of_device_id mchp_tc_dt_ids[] = {
	{ .compatible = "microchip,tcb-capture", },
	{ /* sentinel */ },
	};
	MODULE_DEVICE_TABLE(of, mchp_tc_dt_ids);

	static struct platform_driver mchp_tc_driver = {
	.probe = mchp_tc_probe,
	.driver = {
	.name = "microchip-tcb-capture",
	.of_match_table = mchp_tc_dt_ids,
	},
	};
	module_platform_driver(mchp_tc_driver);

	MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>");
	MODULE_DESCRIPTION("Microchip TCB Capture driver");
	MODULE_LICENSE("GPL v2");