linux-imx

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

//

// Synopsys CREG (Control REGisters) GPIO driver

//

// Copyright (C) 2018 Synopsys

// Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>

​

#include <linux/gpio/driver.h>

#include <linux/io.h>

#include <linux/of.h>

#include <linux/of_platform.h>

​

#define MAX_GPIO    32

​

struct creg_layout {

    u8 ngpio;

    u8 shift[MAX_GPIO];

    u8 on[MAX_GPIO];

    u8 off[MAX_GPIO];

    u8 bit_per_gpio[MAX_GPIO];

};

​

struct creg_gpio {

    struct gpio_chip gc;

    void __iomem *regs;

    spinlock_t lock;

    const struct creg_layout *layout;

};

​

static void creg_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)

{

    struct creg_gpio *hcg = gpiochip_get_data(gc);

    const struct creg_layout *layout = hcg->layout;

    u32 reg, reg_shift, value;

    unsigned long flags;

    int i;

​

    value = val ? hcg->layout->on[offset] : hcg->layout->off[offset];

​

    reg_shift = layout->shift[offset];

    for (i = 0; i < offset; i++)

        reg_shift += layout->bit_per_gpio[i] + layout->shift[i];

​

    spin_lock_irqsave(&hcg->lock, flags);

    reg = readl(hcg->regs);

    reg &= ~(GENMASK(layout->bit_per_gpio[i] - 1, 0) << reg_shift);

    reg |=  (value << reg_shift);

    writel(reg, hcg->regs);

    spin_unlock_irqrestore(&hcg->lock, flags);

}

​

static int creg_gpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val)

{

    creg_gpio_set(gc, offset, val);

​

    return 0;

}

​

static int creg_gpio_validate_pg(struct device *dev, struct creg_gpio *hcg,

                 int i)

{

    const struct creg_layout *layout = hcg->layout;

​