[linux.git] / drivers / iio / dac / stm32-dac-core.c

// SPDX-License-Identifier: GPL-2.0
/*
 * This file is part of STM32 DAC driver
 *
 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
 * Author: Fabrice Gasnier <[email protected]>.
 *
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>

#include "stm32-dac-core.h"

/**
 * struct stm32_dac_priv - stm32 DAC core private data
 * @pclk:		peripheral clock common for all DACs
 * @rst:		peripheral reset control
 * @vref:		regulator reference
 * @common:		Common data for all DAC instances
 */
struct stm32_dac_priv {
	struct clk *pclk;
	struct reset_control *rst;
	struct regulator *vref;
	struct stm32_dac_common common;
};

/**
 * struct stm32_dac_cfg - DAC configuration
 * @has_hfsel: DAC has high frequency control
 */
struct stm32_dac_cfg {
	bool has_hfsel;
};

static struct stm32_dac_priv *to_stm32_dac_priv(struct stm32_dac_common *com)
{
	return container_of(com, struct stm32_dac_priv, common);
}

static const struct regmap_config stm32_dac_regmap_cfg = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = sizeof(u32),
	.max_register = 0x3fc,
};

static int stm32_dac_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct stm32_dac_cfg *cfg;
	struct stm32_dac_priv *priv;
	struct regmap *regmap;
	struct resource *res;
	void __iomem *mmio;
	int ret;

	if (!dev->of_node)
		return -ENODEV;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;
	cfg = (const struct stm32_dac_cfg *)
		of_match_device(dev->driver->of_match_table, dev)->data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	mmio = devm_ioremap_resource(dev, res);
	if (IS_ERR(mmio))
		return PTR_ERR(mmio);

	regmap = devm_regmap_init_mmio(dev, mmio, &stm32_dac_regmap_cfg);
	if (IS_ERR(regmap))
		return PTR_ERR(regmap);
	priv->common.regmap = regmap;

	priv->vref = devm_regulator_get(dev, "vref");
	if (IS_ERR(priv->vref)) {
		ret = PTR_ERR(priv->vref);
		dev_err(dev, "vref get failed, %d\n", ret);
		return ret;
	}

	ret = regulator_enable(priv->vref);
	if (ret < 0) {
		dev_err(dev, "vref enable failed\n");
		return ret;
	}

	ret = regulator_get_voltage(priv->vref);
	if (ret < 0) {
		dev_err(dev, "vref get voltage failed, %d\n", ret);
		goto err_vref;
	}
	priv->common.vref_mv = ret / 1000;
	dev_dbg(dev, "vref+=%dmV\n", priv->common.vref_mv);

	priv->pclk = devm_clk_get(dev, "pclk");
	if (IS_ERR(priv->pclk)) {
		ret = PTR_ERR(priv->pclk);
		dev_err(dev, "pclk get failed\n");
		goto err_vref;
	}

	ret = clk_prepare_enable(priv->pclk);
	if (ret < 0) {
		dev_err(dev, "pclk enable failed\n");
		goto err_vref;
	}

	priv->rst = devm_reset_control_get_exclusive(dev, NULL);
	if (!IS_ERR(priv->rst)) {
		reset_control_assert(priv->rst);
		udelay(2);
		reset_control_deassert(priv->rst);
	}

	if (cfg && cfg->has_hfsel) {
		/* When clock speed is higher than 80MHz, set HFSEL */
		priv->common.hfsel = (clk_get_rate(priv->pclk) > 80000000UL);
		ret = regmap_update_bits(regmap, STM32_DAC_CR,
					 STM32H7_DAC_CR_HFSEL,
					 priv->common.hfsel ?
					 STM32H7_DAC_CR_HFSEL : 0);
		if (ret)
			goto err_pclk;
	}

	platform_set_drvdata(pdev, &priv->common);

	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, dev);
	if (ret < 0) {
		dev_err(dev, "failed to populate DT children\n");
		goto err_pclk;
	}

	return 0;

err_pclk:
	clk_disable_unprepare(priv->pclk);
err_vref:
	regulator_disable(priv->vref);

	return ret;
}

static int stm32_dac_remove(struct platform_device *pdev)
{
	struct stm32_dac_common *common = platform_get_drvdata(pdev);
	struct stm32_dac_priv *priv = to_stm32_dac_priv(common);

	of_platform_depopulate(&pdev->dev);
	clk_disable_unprepare(priv->pclk);
	regulator_disable(priv->vref);

	return 0;
}

static const struct stm32_dac_cfg stm32h7_dac_cfg = {
	.has_hfsel = true,
};

static const struct of_device_id stm32_dac_of_match[] = {
	{
		.compatible = "st,stm32f4-dac-core",
	}, {
		.compatible = "st,stm32h7-dac-core",
		.data = (void *)&stm32h7_dac_cfg,
	},
	{},
};
MODULE_DEVICE_TABLE(of, stm32_dac_of_match);

static struct platform_driver stm32_dac_driver = {
	.probe = stm32_dac_probe,
	.remove = stm32_dac_remove,
	.driver = {
		.name = "stm32-dac-core",
		.of_match_table = stm32_dac_of_match,
	},
};
module_platform_driver(stm32_dac_driver);

MODULE_AUTHOR("Fabrice Gasnier <[email protected]>");
MODULE_DESCRIPTION("STMicroelectronics STM32 DAC core driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:stm32-dac-core");
Commit	Line	Data
6e93e261	1	// SPDX-License-Identifier: GPL-2.0
4d4b3052 FG	2	/*
	3	* This file is part of STM32 DAC driver
	4	*
	5	* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
	6	* Author: Fabrice Gasnier <[email protected]>.
	7	*
4d4b3052 FG	8	*/
	9
	10	#include <linux/clk.h>
	11	#include <linux/delay.h>
	12	#include <linux/module.h>
	13	#include <linux/of_platform.h>
	14	#include <linux/regulator/consumer.h>
	15	#include <linux/reset.h>
	16
	17	#include "stm32-dac-core.h"
	18
	19	/**
	20	* struct stm32_dac_priv - stm32 DAC core private data
	21	* @pclk: peripheral clock common for all DACs
	22	* @rst: peripheral reset control
	23	* @vref: regulator reference
	24	* @common: Common data for all DAC instances
	25	*/
	26	struct stm32_dac_priv {
	27	struct clk *pclk;
	28	struct reset_control *rst;
	29	struct regulator *vref;
	30	struct stm32_dac_common common;
	31	};
	32
9d9ebe64 FG	33	/**
	34	* struct stm32_dac_cfg - DAC configuration
	35	* @has_hfsel: DAC has high frequency control
	36	*/
	37	struct stm32_dac_cfg {
	38	bool has_hfsel;
	39	};
	40
4d4b3052 FG	41	static struct stm32_dac_priv to_stm32_dac_priv(struct stm32_dac_common com)
	42	{
	43	return container_of(com, struct stm32_dac_priv, common);
	44	}
	45
	46	static const struct regmap_config stm32_dac_regmap_cfg = {
	47	.reg_bits = 32,
	48	.val_bits = 32,
	49	.reg_stride = sizeof(u32),
	50	.max_register = 0x3fc,
	51	};
	52
	53	static int stm32_dac_probe(struct platform_device *pdev)
	54	{
	55	struct device *dev = &pdev->dev;
9d9ebe64	56	const struct stm32_dac_cfg *cfg;
4d4b3052 FG	57	struct stm32_dac_priv *priv;
	58	struct regmap *regmap;
	59	struct resource *res;
	60	void __iomem *mmio;
	61	int ret;
	62
	63	if (!dev->of_node)
	64	return -ENODEV;
	65
	66	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	67	if (!priv)
	68	return -ENOMEM;
9d9ebe64 FG	69	cfg = (const struct stm32_dac_cfg *)
9d9ebe64 FG	70	of_match_device(dev->driver->of_match_table, dev)->data;
4d4b3052 FG	71
	72	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	73	mmio = devm_ioremap_resource(dev, res);
	74	if (IS_ERR(mmio))
	75	return PTR_ERR(mmio);
	76
	77	regmap = devm_regmap_init_mmio(dev, mmio, &stm32_dac_regmap_cfg);
	78	if (IS_ERR(regmap))
	79	return PTR_ERR(regmap);
	80	priv->common.regmap = regmap;
	81
	82	priv->vref = devm_regulator_get(dev, "vref");
	83	if (IS_ERR(priv->vref)) {
	84	ret = PTR_ERR(priv->vref);
	85	dev_err(dev, "vref get failed, %d\n", ret);
	86	return ret;
	87	}
	88
	89	ret = regulator_enable(priv->vref);
	90	if (ret < 0) {
	91	dev_err(dev, "vref enable failed\n");
	92	return ret;
	93	}
	94
	95	ret = regulator_get_voltage(priv->vref);
	96	if (ret < 0) {
	97	dev_err(dev, "vref get voltage failed, %d\n", ret);
	98	goto err_vref;
	99	}
	100	priv->common.vref_mv = ret / 1000;
	101	dev_dbg(dev, "vref+=%dmV\n", priv->common.vref_mv);
	102
	103	priv->pclk = devm_clk_get(dev, "pclk");
	104	if (IS_ERR(priv->pclk)) {
	105	ret = PTR_ERR(priv->pclk);
	106	dev_err(dev, "pclk get failed\n");
	107	goto err_vref;
	108	}
	109
	110	ret = clk_prepare_enable(priv->pclk);
	111	if (ret < 0) {
	112	dev_err(dev, "pclk enable failed\n");
	113	goto err_vref;
	114	}
	115
a1b509df	116	priv->rst = devm_reset_control_get_exclusive(dev, NULL);
4d4b3052 FG	117	if (!IS_ERR(priv->rst)) {
	118	reset_control_assert(priv->rst);
	119	udelay(2);
	120	reset_control_deassert(priv->rst);
	121	}
	122
9d9ebe64 FG	123	if (cfg && cfg->has_hfsel) {
	124	/* When clock speed is higher than 80MHz, set HFSEL */
	125	priv->common.hfsel = (clk_get_rate(priv->pclk) > 80000000UL);
	126	ret = regmap_update_bits(regmap, STM32_DAC_CR,
	127	STM32H7_DAC_CR_HFSEL,
	128	priv->common.hfsel ?
	129	STM32H7_DAC_CR_HFSEL : 0);
	130	if (ret)
	131	goto err_pclk;
	132	}
4d4b3052 FG	133
	134	platform_set_drvdata(pdev, &priv->common);
	135
	136	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, dev);
	137	if (ret < 0) {
	138	dev_err(dev, "failed to populate DT children\n");
	139	goto err_pclk;
	140	}
	141
	142	return 0;
	143
	144	err_pclk:
	145	clk_disable_unprepare(priv->pclk);
	146	err_vref:
	147	regulator_disable(priv->vref);
	148
	149	return ret;
	150	}
	151
	152	static int stm32_dac_remove(struct platform_device *pdev)
	153	{
	154	struct stm32_dac_common *common = platform_get_drvdata(pdev);
	155	struct stm32_dac_priv *priv = to_stm32_dac_priv(common);
	156
	157	of_platform_depopulate(&pdev->dev);
	158	clk_disable_unprepare(priv->pclk);
	159	regulator_disable(priv->vref);
	160
	161	return 0;
	162	}
	163
9d9ebe64 FG	164	static const struct stm32_dac_cfg stm32h7_dac_cfg = {
	165	.has_hfsel = true,
	166	};
	167
4d4b3052	168	static const struct of_device_id stm32_dac_of_match[] = {
9d9ebe64 FG	169	{
	170	.compatible = "st,stm32f4-dac-core",
	171	}, {
	172	.compatible = "st,stm32h7-dac-core",
	173	.data = (void *)&stm32h7_dac_cfg,
	174	},
4d4b3052 FG	175	{},
	176	};
	177	MODULE_DEVICE_TABLE(of, stm32_dac_of_match);
	178
	179	static struct platform_driver stm32_dac_driver = {
	180	.probe = stm32_dac_probe,
	181	.remove = stm32_dac_remove,
	182	.driver = {
	183	.name = "stm32-dac-core",
	184	.of_match_table = stm32_dac_of_match,
	185	},
	186	};
	187	module_platform_driver(stm32_dac_driver);
	188
	189	MODULE_AUTHOR("Fabrice Gasnier <[email protected]>");
	190	MODULE_DESCRIPTION("STMicroelectronics STM32 DAC core driver");
	191	MODULE_LICENSE("GPL v2");
	192	MODULE_ALIAS("platform:stm32-dac-core");