[mirror_ubuntu-bionic-kernel.git] / drivers / pwm / pwm-mediatek.c

/*
 * Mediatek Pulse Width Modulator driver
 *
 * Copyright (C) 2015 John Crispin <blogic@openwrt.org>
 * Copyright (C) 2017 Zhi Mao <zhi.mao@mediatek.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
#include <linux/slab.h>
#include <linux/types.h>

/* PWM registers and bits definitions */
#define PWMCON			0x00
#define PWMHDUR			0x04
#define PWMLDUR			0x08
#define PWMGDUR			0x0c
#define PWMWAVENUM		0x28
#define PWMDWIDTH		0x2c
#define PWM45DWIDTH_FIXUP	0x30
#define PWMTHRES		0x30
#define PWM45THRES_FIXUP	0x34

#define PWM_CLK_DIV_MAX		7

enum {
	MTK_CLK_MAIN = 0,
	MTK_CLK_TOP,
	MTK_CLK_PWM1,
	MTK_CLK_PWM2,
	MTK_CLK_PWM3,
	MTK_CLK_PWM4,
	MTK_CLK_PWM5,
	MTK_CLK_PWM6,
	MTK_CLK_PWM7,
	MTK_CLK_PWM8,
	MTK_CLK_MAX,
};

static const char * const mtk_pwm_clk_name[MTK_CLK_MAX] = {
	"main", "top", "pwm1", "pwm2", "pwm3", "pwm4", "pwm5", "pwm6", "pwm7",
	"pwm8"
};

struct mtk_pwm_platform_data {
	unsigned int num_pwms;
	bool pwm45_fixup;
};

/**
 * struct mtk_pwm_chip - struct representing PWM chip
 * @chip: linux PWM chip representation
 * @regs: base address of PWM chip
 * @clks: list of clocks
 */
struct mtk_pwm_chip {
	struct pwm_chip chip;
	void __iomem *regs;
	struct clk *clks[MTK_CLK_MAX];
	const struct mtk_pwm_platform_data *soc;
};

static const unsigned int mtk_pwm_reg_offset[] = {
	0x0010, 0x0050, 0x0090, 0x00d0, 0x0110, 0x0150, 0x0190, 0x0220
};

static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct pwm_chip *chip)
{
	return container_of(chip, struct mtk_pwm_chip, chip);
}

static int mtk_pwm_clk_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	int ret;

	ret = clk_prepare_enable(pc->clks[MTK_CLK_TOP]);
	if (ret < 0)
		return ret;

	ret = clk_prepare_enable(pc->clks[MTK_CLK_MAIN]);
	if (ret < 0)
		goto disable_clk_top;

	ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
	if (ret < 0)
		goto disable_clk_main;

	return 0;

disable_clk_main:
	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
disable_clk_top:
	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);

	return ret;
}

static void mtk_pwm_clk_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);

	clk_disable_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
}

static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
				unsigned int offset)
{
	return readl(chip->regs + mtk_pwm_reg_offset[num] + offset);
}

static inline void mtk_pwm_writel(struct mtk_pwm_chip *chip,
				  unsigned int num, unsigned int offset,
				  u32 value)
{
	writel(value, chip->regs + mtk_pwm_reg_offset[num] + offset);
}

static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
			  int duty_ns, int period_ns)
{
	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	struct clk *clk = pc->clks[MTK_CLK_PWM1 + pwm->hwpwm];
	u32 clkdiv = 0, cnt_period, cnt_duty, reg_width = PWMDWIDTH,
	    reg_thres = PWMTHRES;
	u64 resolution;
	int ret;

	ret = mtk_pwm_clk_enable(chip, pwm);
	if (ret < 0)
		return ret;

	/* Using resolution in picosecond gets accuracy higher */
	resolution = (u64)NSEC_PER_SEC * 1000;
	do_div(resolution, clk_get_rate(clk));

	cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000, resolution);
	while (cnt_period > 8191) {
		resolution *= 2;
		clkdiv++;
		cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000,
						   resolution);
	}

	if (clkdiv > PWM_CLK_DIV_MAX) {
		mtk_pwm_clk_disable(chip, pwm);
		dev_err(chip->dev, "period %d not supported\n", period_ns);
		return -EINVAL;
	}

	if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) {
		/*
		 * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES
		 * from the other PWMs on MT7623.
		 */
		reg_width = PWM45DWIDTH_FIXUP;
		reg_thres = PWM45THRES_FIXUP;
	}

	cnt_duty = DIV_ROUND_CLOSEST_ULL((u64)duty_ns * 1000, resolution);
	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv);
	mtk_pwm_writel(pc, pwm->hwpwm, reg_width, cnt_period);
	mtk_pwm_writel(pc, pwm->hwpwm, reg_thres, cnt_duty);

	mtk_pwm_clk_disable(chip, pwm);

	return 0;
}

static int mtk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	u32 value;
	int ret;

	ret = mtk_pwm_clk_enable(chip, pwm);
	if (ret < 0)
		return ret;

	value = readl(pc->regs);
	value |= BIT(pwm->hwpwm);
	writel(value, pc->regs);

	return 0;
}

static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	u32 value;

	value = readl(pc->regs);
	value &= ~BIT(pwm->hwpwm);
	writel(value, pc->regs);

	mtk_pwm_clk_disable(chip, pwm);
}

static const struct pwm_ops mtk_pwm_ops = {
	.config = mtk_pwm_config,
	.enable = mtk_pwm_enable,
	.disable = mtk_pwm_disable,
	.owner = THIS_MODULE,
};

static int mtk_pwm_probe(struct platform_device *pdev)
{
	const struct mtk_pwm_platform_data *data;
	struct mtk_pwm_chip *pc;
	struct resource *res;
	unsigned int i;
	int ret;

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

	data = of_device_get_match_data(&pdev->dev);
	if (data == NULL)
		return -EINVAL;
	pc->soc = data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	pc->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(pc->regs))
		return PTR_ERR(pc->regs);

	for (i = 0; i < data->num_pwms + 2; i++) {
		pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
		if (IS_ERR(pc->clks[i])) {
			dev_err(&pdev->dev, "clock: %s fail: %ld\n",
				mtk_pwm_clk_name[i], PTR_ERR(pc->clks[i]));
			return PTR_ERR(pc->clks[i]);
		}
	}

	platform_set_drvdata(pdev, pc);

	pc->chip.dev = &pdev->dev;
	pc->chip.ops = &mtk_pwm_ops;
	pc->chip.base = -1;
	pc->chip.npwm = data->num_pwms;

	ret = pwmchip_add(&pc->chip);
	if (ret < 0) {
		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
		return ret;
	}

	return 0;
}

static int mtk_pwm_remove(struct platform_device *pdev)
{
	struct mtk_pwm_chip *pc = platform_get_drvdata(pdev);

	return pwmchip_remove(&pc->chip);
}

static const struct mtk_pwm_platform_data mt2712_pwm_data = {
	.num_pwms = 8,
	.pwm45_fixup = false,
};

static const struct mtk_pwm_platform_data mt7622_pwm_data = {
	.num_pwms = 6,
	.pwm45_fixup = false,
};

static const struct mtk_pwm_platform_data mt7623_pwm_data = {
	.num_pwms = 5,
	.pwm45_fixup = true,
};

static const struct of_device_id mtk_pwm_of_match[] = {
	{ .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data },
	{ .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data },
	{ .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data },
	{ },
};
MODULE_DEVICE_TABLE(of, mtk_pwm_of_match);

static struct platform_driver mtk_pwm_driver = {
	.driver = {
		.name = "mtk-pwm",
		.of_match_table = mtk_pwm_of_match,
	},
	.probe = mtk_pwm_probe,
	.remove = mtk_pwm_remove,
};
module_platform_driver(mtk_pwm_driver);

MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
MODULE_ALIAS("platform:mtk-pwm");
MODULE_LICENSE("GPL");
Commit	Line	Data
caf065f8 JC	1	/*
	2	* Mediatek Pulse Width Modulator driver
	3	*
	4	* Copyright (C) 2015 John Crispin <blogic@openwrt.org>
e7c197ec	5	* Copyright (C) 2017 Zhi Mao <zhi.mao@mediatek.com>
caf065f8 JC	6	*
	7	* This file is licensed under the terms of the GNU General Public
	8	* License version 2. This program is licensed "as is" without any
	9	* warranty of any kind, whether express or implied.
	10	*/
	11
	12	#include <linux/err.h>
	13	#include <linux/io.h>
	14	#include <linux/ioport.h>
	15	#include <linux/kernel.h>
	16	#include <linux/module.h>
	17	#include <linux/clk.h>
	18	#include <linux/of.h>
424268c7	19	#include <linux/of_device.h>
caf065f8 JC	20	#include <linux/platform_device.h>
	21	#include <linux/pwm.h>
	22	#include <linux/slab.h>
	23	#include <linux/types.h>
	24
	25	/* PWM registers and bits definitions */
	26	#define PWMCON 0x00
	27	#define PWMHDUR 0x04
	28	#define PWMLDUR 0x08
	29	#define PWMGDUR 0x0c
	30	#define PWMWAVENUM 0x28
	31	#define PWMDWIDTH 0x2c
b350333c	32	#define PWM45DWIDTH_FIXUP 0x30
caf065f8	33	#define PWMTHRES 0x30
b350333c	34	#define PWM45THRES_FIXUP 0x34
caf065f8	35
8bdb65dc ZM	36	#define PWM_CLK_DIV_MAX 7
8bdb65dc ZM	37
caf065f8 JC	38	enum {
	39	MTK_CLK_MAIN = 0,
	40	MTK_CLK_TOP,
	41	MTK_CLK_PWM1,
	42	MTK_CLK_PWM2,
	43	MTK_CLK_PWM3,
	44	MTK_CLK_PWM4,
	45	MTK_CLK_PWM5,
424268c7 ZM	46	MTK_CLK_PWM6,
	47	MTK_CLK_PWM7,
	48	MTK_CLK_PWM8,
caf065f8 JC	49	MTK_CLK_MAX,
	50	};
	51
424268c7 ZM	52	static const char * const mtk_pwm_clk_name[MTK_CLK_MAX] = {
	53	"main", "top", "pwm1", "pwm2", "pwm3", "pwm4", "pwm5", "pwm6", "pwm7",
	54	"pwm8"
	55	};
	56
	57	struct mtk_pwm_platform_data {
	58	unsigned int num_pwms;
b350333c	59	bool pwm45_fixup;
caf065f8 JC	60	};
	61
	62	/**
	63	* struct mtk_pwm_chip - struct representing PWM chip
	64	* @chip: linux PWM chip representation
	65	* @regs: base address of PWM chip
	66	* @clks: list of clocks
	67	*/
	68	struct mtk_pwm_chip {
	69	struct pwm_chip chip;
	70	void __iomem *regs;
	71	struct clk *clks[MTK_CLK_MAX];
b350333c	72	const struct mtk_pwm_platform_data *soc;
caf065f8 JC	73	};
caf065f8 JC	74
424268c7 ZM	75	static const unsigned int mtk_pwm_reg_offset[] = {
	76	0x0010, 0x0050, 0x0090, 0x00d0, 0x0110, 0x0150, 0x0190, 0x0220
	77	};
	78
caf065f8 JC	79	static inline struct mtk_pwm_chip to_mtk_pwm_chip(struct pwm_chip chip)
	80	{
	81	return container_of(chip, struct mtk_pwm_chip, chip);
	82	}
	83
e7c197ec ZM	84	static int mtk_pwm_clk_enable(struct pwm_chip chip, struct pwm_device pwm)
	85	{
	86	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	87	int ret;
	88
	89	ret = clk_prepare_enable(pc->clks[MTK_CLK_TOP]);
	90	if (ret < 0)
	91	return ret;
	92
	93	ret = clk_prepare_enable(pc->clks[MTK_CLK_MAIN]);
	94	if (ret < 0)
	95	goto disable_clk_top;
	96
	97	ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
	98	if (ret < 0)
	99	goto disable_clk_main;
	100
	101	return 0;
	102
	103	disable_clk_main:
	104	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
	105	disable_clk_top:
	106	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
	107
	108	return ret;
	109	}
	110
	111	static void mtk_pwm_clk_disable(struct pwm_chip chip, struct pwm_device pwm)
	112	{
	113	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	114
	115	clk_disable_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]);
	116	clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]);
	117	clk_disable_unprepare(pc->clks[MTK_CLK_TOP]);
	118	}
	119
caf065f8 JC	120	static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num,
	121	unsigned int offset)
	122	{
424268c7	123	return readl(chip->regs + mtk_pwm_reg_offset[num] + offset);
caf065f8 JC	124	}
	125
	126	static inline void mtk_pwm_writel(struct mtk_pwm_chip *chip,
	127	unsigned int num, unsigned int offset,
	128	u32 value)
	129	{
424268c7	130	writel(value, chip->regs + mtk_pwm_reg_offset[num] + offset);
caf065f8 JC	131	}
	132
	133	static int mtk_pwm_config(struct pwm_chip chip, struct pwm_device pwm,
	134	int duty_ns, int period_ns)
	135	{
	136	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	137	struct clk *clk = pc->clks[MTK_CLK_PWM1 + pwm->hwpwm];
0d72414b	138	u32 clkdiv = 0, cnt_period, cnt_duty, reg_width = PWMDWIDTH,
b350333c	139	reg_thres = PWMTHRES;
0d72414b	140	u64 resolution;
e7c197ec ZM	141	int ret;
	142
	143	ret = mtk_pwm_clk_enable(chip, pwm);
	144	if (ret < 0)
	145	return ret;
caf065f8	146
0d72414b SW	147	/* Using resolution in picosecond gets accuracy higher */
	148	resolution = (u64)NSEC_PER_SEC * 1000;
	149	do_div(resolution, clk_get_rate(clk));
caf065f8	150
0d72414b SW	151	cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000, resolution);
0d72414b SW	152	while (cnt_period > 8191) {
caf065f8 JC	153	resolution *= 2;
caf065f8 JC	154	clkdiv++;
0d72414b SW	155	cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000,
0d72414b SW	156	resolution);
caf065f8 JC	157	}
caf065f8 JC	158
8bdb65dc ZM	159	if (clkdiv > PWM_CLK_DIV_MAX) {
	160	mtk_pwm_clk_disable(chip, pwm);
	161	dev_err(chip->dev, "period %d not supported\n", period_ns);
caf065f8	162	return -EINVAL;
8bdb65dc	163	}
caf065f8	164
b350333c SW	165	if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) {
	166	/*
	167	* PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES
	168	* from the other PWMs on MT7623.
	169	*/
	170	reg_width = PWM45DWIDTH_FIXUP;
	171	reg_thres = PWM45THRES_FIXUP;
	172	}
	173
0d72414b	174	cnt_duty = DIV_ROUND_CLOSEST_ULL((u64)duty_ns * 1000, resolution);
cd30798a	175	mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) \| clkdiv);
0d72414b SW	176	mtk_pwm_writel(pc, pwm->hwpwm, reg_width, cnt_period);
0d72414b SW	177	mtk_pwm_writel(pc, pwm->hwpwm, reg_thres, cnt_duty);
caf065f8	178
e7c197ec ZM	179	mtk_pwm_clk_disable(chip, pwm);
e7c197ec ZM	180
caf065f8 JC	181	return 0;
	182	}
	183
	184	static int mtk_pwm_enable(struct pwm_chip chip, struct pwm_device pwm)
	185	{
	186	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	187	u32 value;
	188	int ret;
	189
e7c197ec	190	ret = mtk_pwm_clk_enable(chip, pwm);
caf065f8 JC	191	if (ret < 0)
	192	return ret;
	193
	194	value = readl(pc->regs);
	195	value \|= BIT(pwm->hwpwm);
	196	writel(value, pc->regs);
	197
	198	return 0;
	199	}
	200
	201	static void mtk_pwm_disable(struct pwm_chip chip, struct pwm_device pwm)
	202	{
	203	struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip);
	204	u32 value;
	205
	206	value = readl(pc->regs);
	207	value &= ~BIT(pwm->hwpwm);
	208	writel(value, pc->regs);
	209
e7c197ec	210	mtk_pwm_clk_disable(chip, pwm);
caf065f8 JC	211	}
	212
	213	static const struct pwm_ops mtk_pwm_ops = {
	214	.config = mtk_pwm_config,
	215	.enable = mtk_pwm_enable,
	216	.disable = mtk_pwm_disable,
	217	.owner = THIS_MODULE,
	218	};
	219
	220	static int mtk_pwm_probe(struct platform_device *pdev)
	221	{
424268c7	222	const struct mtk_pwm_platform_data *data;
caf065f8 JC	223	struct mtk_pwm_chip *pc;
	224	struct resource *res;
	225	unsigned int i;
	226	int ret;
	227
	228	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
	229	if (!pc)
	230	return -ENOMEM;
	231
424268c7 ZM	232	data = of_device_get_match_data(&pdev->dev);
	233	if (data == NULL)
	234	return -EINVAL;
b350333c	235	pc->soc = data;
424268c7	236
caf065f8 JC	237	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	238	pc->regs = devm_ioremap_resource(&pdev->dev, res);
	239	if (IS_ERR(pc->regs))
	240	return PTR_ERR(pc->regs);
	241
424268c7	242	for (i = 0; i < data->num_pwms + 2; i++) {
caf065f8	243	pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
424268c7 ZM	244	if (IS_ERR(pc->clks[i])) {
	245	dev_err(&pdev->dev, "clock: %s fail: %ld\n",
	246	mtk_pwm_clk_name[i], PTR_ERR(pc->clks[i]));
caf065f8	247	return PTR_ERR(pc->clks[i]);
424268c7	248	}
caf065f8 JC	249	}
caf065f8 JC	250
caf065f8 JC	251	platform_set_drvdata(pdev, pc);
	252
	253	pc->chip.dev = &pdev->dev;
	254	pc->chip.ops = &mtk_pwm_ops;
	255	pc->chip.base = -1;
424268c7	256	pc->chip.npwm = data->num_pwms;
caf065f8 JC	257
	258	ret = pwmchip_add(&pc->chip);
	259	if (ret < 0) {
	260	dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
e7c197ec	261	return ret;
caf065f8 JC	262	}
	263
	264	return 0;
caf065f8 JC	265	}
	266
	267	static int mtk_pwm_remove(struct platform_device *pdev)
	268	{
	269	struct mtk_pwm_chip *pc = platform_get_drvdata(pdev);
caf065f8 JC	270
	271	return pwmchip_remove(&pc->chip);
	272	}
	273
424268c7 ZM	274	static const struct mtk_pwm_platform_data mt2712_pwm_data = {
424268c7 ZM	275	.num_pwms = 8,
b350333c	276	.pwm45_fixup = false,
424268c7 ZM	277	};
	278
	279	static const struct mtk_pwm_platform_data mt7622_pwm_data = {
	280	.num_pwms = 6,
b350333c	281	.pwm45_fixup = false,
424268c7 ZM	282	};
	283
	284	static const struct mtk_pwm_platform_data mt7623_pwm_data = {
	285	.num_pwms = 5,
b350333c	286	.pwm45_fixup = true,
424268c7 ZM	287	};
424268c7 ZM	288
caf065f8	289	static const struct of_device_id mtk_pwm_of_match[] = {
424268c7 ZM	290	{ .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data },
	291	{ .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data },
	292	{ .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data },
	293	{ },
caf065f8 JC	294	};
	295	MODULE_DEVICE_TABLE(of, mtk_pwm_of_match);
	296
	297	static struct platform_driver mtk_pwm_driver = {
	298	.driver = {
	299	.name = "mtk-pwm",
caf065f8 JC	300	.of_match_table = mtk_pwm_of_match,
	301	},
	302	.probe = mtk_pwm_probe,
	303	.remove = mtk_pwm_remove,
	304	};
	305	module_platform_driver(mtk_pwm_driver);
	306
	307	MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
	308	MODULE_ALIAS("platform:mtk-pwm");
	309	MODULE_LICENSE("GPL");