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Commit f6306299 authored by Caesar Wang's avatar Caesar Wang Committed by Thierry Reding
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pwm: rockchip: Added to support for RK3288 SoC 



This patch added to support the PWM controller found on
RK3288 SoC.

Signed-off-by: default avatarCaesar Wang <caesar.wang@rock-chips.com>
Signed-off-by: default avatarThierry Reding <thierry.reding@gmail.com>
parent 695d49d9

drivers/pwm/pwm-rockchip.c

+111 −24
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 
 * PWM driver for Rockchip SoCs

 *

 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>

 * Copyright (C) 2014 ROCKCHIP, Inc.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License
@@ -12,30 +13,81 @@ 
#include <linux/io.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/platform_device.h>

#include <linux/pwm.h>

#include <linux/time.h>



#define PWM_CNTR		0x00		/* Counter register */

#define PWM_HRC			0x04		/* High reference register */

#define PWM_LRC			0x08		/* Low reference register */

#define PWM_CTRL		0x0c		/* Control register */

#define PWM_CTRL_TIMER_EN	(1 << 0)

#define PWM_CTRL_OUTPUT_EN	(1 << 3)



#define PRESCALER		2

#define PWM_ENABLE		(1 << 0)

#define PWM_CONTINUOUS		(1 << 1)

#define PWM_DUTY_POSITIVE	(1 << 3)

#define PWM_INACTIVE_NEGATIVE	(0 << 4)

#define PWM_OUTPUT_LEFT		(0 << 5)

#define PWM_LP_DISABLE		(0 << 8)



struct rockchip_pwm_chip {

	struct pwm_chip chip;

	struct clk *clk;

	const struct rockchip_pwm_data *data;

	void __iomem *base;

};



struct rockchip_pwm_regs {

	unsigned long duty;

	unsigned long period;

	unsigned long cntr;

	unsigned long ctrl;

};



struct rockchip_pwm_data {

	struct rockchip_pwm_regs regs;

	unsigned int prescaler;



	void (*set_enable)(struct pwm_chip *chip, bool enable);

};



static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)

{

	return container_of(c, struct rockchip_pwm_chip, chip);

}



static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, bool enable)

{

	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);

	u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;

	u32 val;



	val = readl_relaxed(pc->base + pc->data->regs.ctrl);



	if (enable)

		val |= enable_conf;

	else

		val &= ~enable_conf;



	writel_relaxed(val, pc->base + pc->data->regs.ctrl);

}



static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, bool enable)

{

	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);

	u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |

			  PWM_CONTINUOUS | PWM_DUTY_POSITIVE |

			  PWM_INACTIVE_NEGATIVE;

	u32 val;



	val = readl_relaxed(pc->base + pc->data->regs.ctrl);



	if (enable)

		val |= enable_conf;

	else

		val &= ~enable_conf;



	writel_relaxed(val, pc->base + pc->data->regs.ctrl);

}



static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,

			       int duty_ns, int period_ns)

{
@@ -52,20 +104,20 @@ static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, 
	 * default prescaler value for all practical clock rate values.

	 */

	div = clk_rate * period_ns;

	do_div(div, PRESCALER * NSEC_PER_SEC);

	do_div(div, pc->data->prescaler * NSEC_PER_SEC);

	period = div;



	div = clk_rate * duty_ns;

	do_div(div, PRESCALER * NSEC_PER_SEC);

	do_div(div, pc->data->prescaler * NSEC_PER_SEC);

	duty = div;



	ret = clk_enable(pc->clk);

	if (ret)

		return ret;



	writel(period, pc->base + PWM_LRC);

	writel(duty, pc->base + PWM_HRC);

	writel(0, pc->base + PWM_CNTR);

	writel(period, pc->base + pc->data->regs.period);

	writel(duty, pc->base + pc->data->regs.duty);

	writel(0, pc->base + pc->data->regs.cntr);



	clk_disable(pc->clk);
@@ -76,15 +128,12 @@ static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) 
{

	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);

	int ret;

	u32 val;



	ret = clk_enable(pc->clk);

	if (ret)

		return ret;



	val = readl_relaxed(pc->base + PWM_CTRL);

	val |= PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;

	writel_relaxed(val, pc->base + PWM_CTRL);

	pc->data->set_enable(chip, true);



	return 0;

}
@@ -92,11 +141,8 @@ static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) 
static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)

{

	struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);

	u32 val;



	val = readl_relaxed(pc->base + PWM_CTRL);

	val &= ~(PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN);

	writel_relaxed(val, pc->base + PWM_CTRL);

	pc->data->set_enable(chip, false);



	clk_disable(pc->clk);

}
@@ -108,12 +154,58 @@ static const struct pwm_ops rockchip_pwm_ops = { 
	.owner = THIS_MODULE,

};



static const struct rockchip_pwm_data pwm_data_v1 = {

	.regs = {

		.duty = 0x04,

		.period = 0x08,

		.cntr = 0x00,

		.ctrl = 0x0c,

	},

	.prescaler = 2,

	.set_enable = rockchip_pwm_set_enable_v1,

};



static const struct rockchip_pwm_data pwm_data_v2 = {

	.regs = {

		.duty = 0x08,

		.period = 0x04,

		.cntr = 0x00,

		.ctrl = 0x0c,

	},

	.prescaler = 1,

	.set_enable = rockchip_pwm_set_enable_v2,

};



static const struct rockchip_pwm_data pwm_data_vop = {

	.regs = {

		.duty = 0x08,

		.period = 0x04,

		.cntr = 0x0c,

		.ctrl = 0x00,

	},

	.prescaler = 1,

	.set_enable = rockchip_pwm_set_enable_v2,

};



static const struct of_device_id rockchip_pwm_dt_ids[] = {

	{ .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},

	{ .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},

	{ .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},

	{ /* sentinel */ }

};

MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);



static int rockchip_pwm_probe(struct platform_device *pdev)

{

	const struct of_device_id *id;

	struct rockchip_pwm_chip *pc;

	struct resource *r;

	int ret;



	id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);

	if (!id)

		return -EINVAL;



	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);

	if (!pc)

		return -ENOMEM;
@@ -133,6 +225,7 @@ static int rockchip_pwm_probe(struct platform_device *pdev) 


	platform_set_drvdata(pdev, pc);



	pc->data = id->data;

	pc->chip.dev = &pdev->dev;

	pc->chip.ops = &rockchip_pwm_ops;

	pc->chip.base = -1;
@@ -156,12 +249,6 @@ static int rockchip_pwm_remove(struct platform_device *pdev) 
	return pwmchip_remove(&pc->chip);

}



static const struct of_device_id rockchip_pwm_dt_ids[] = {

	{ .compatible = "rockchip,rk2928-pwm" },

	{ /* sentinel */ }

};

MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);



static struct platform_driver rockchip_pwm_driver = {

	.driver = {

		.name = "rockchip-pwm",