linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 * Cirrus Logic CLPS711X PWM driver

 * Author: Alexander Shiyan <shc_work@mail.ru>

 */

​

#include <linux/clk.h>

#include <linux/io.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/pwm.h>

​

struct clps711x_chip {

    struct pwm_chip chip;

    void __iomem *pmpcon;

    struct clk *clk;

    spinlock_t lock;

};

​

static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip)

{

    return container_of(chip, struct clps711x_chip, chip);

}

​

static void clps711x_pwm_update_val(struct clps711x_chip *priv, u32 n, u32 v)

{

    /* PWM0 - bits 4..7, PWM1 - bits 8..11 */

    u32 shift = (n + 1) * 4;

    unsigned long flags;

    u32 tmp;

​

    spin_lock_irqsave(&priv->lock, flags);

​

    tmp = readl(priv->pmpcon);

    tmp &= ~(0xf << shift);

    tmp |= v << shift;

    writel(tmp, priv->pmpcon);

​

    spin_unlock_irqrestore(&priv->lock, flags);

}

​

static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v)

{

    /* Duty cycle 0..15 max */

    return DIV_ROUND_CLOSEST(v * 0xf, pwm->args.period);

}

​

static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)

{

    struct clps711x_chip *priv = to_clps711x_chip(chip);

    unsigned int freq = clk_get_rate(priv->clk);

​

    if (!freq)

        return -EINVAL;

​

    /* Store constant period value */

    pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq);

​

    return 0;

}

​

static int clps711x_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,