[mirror_ubuntu-bionic-kernel.git] / drivers / gpio / gpio-loongson1.c

/*
 * GPIO Driver for Loongson 1 SoC
 *
 * Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.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/module.h>
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/bitops.h>

/* Loongson 1 GPIO Register Definitions */
#define GPIO_CFG		0x0
#define GPIO_DIR		0x10
#define GPIO_DATA		0x20
#define GPIO_OUTPUT		0x30

static void __iomem *gpio_reg_base;

static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
{
	unsigned long flags;

	spin_lock_irqsave(&gc->bgpio_lock, flags);
	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset),
		     gpio_reg_base + GPIO_CFG);
	spin_unlock_irqrestore(&gc->bgpio_lock, flags);

	return 0;
}

static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
{
	unsigned long flags;

	spin_lock_irqsave(&gc->bgpio_lock, flags);
	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
		     gpio_reg_base + GPIO_CFG);
	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
}

static int ls1x_gpio_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct gpio_chip *gc;
	struct resource *res;
	int ret;

	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
	if (!gc)
		return -ENOMEM;

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

	ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
			 gpio_reg_base + GPIO_OUTPUT, NULL,
			 NULL, gpio_reg_base + GPIO_DIR, 0);
	if (ret)
		goto err;

	gc->owner = THIS_MODULE;
	gc->request = ls1x_gpio_request;
	gc->free = ls1x_gpio_free;
	gc->base = pdev->id * 32;

	ret = devm_gpiochip_add_data(dev, gc, NULL);
	if (ret)
		goto err;

	platform_set_drvdata(pdev, gc);
	dev_info(dev, "Loongson1 GPIO driver registered\n");

	return 0;
err:
	dev_err(dev, "failed to register GPIO device\n");
	return ret;
}

static struct platform_driver ls1x_gpio_driver = {
	.probe	= ls1x_gpio_probe,
	.driver	= {
		.name	= "ls1x-gpio",
	},
};

module_platform_driver(ls1x_gpio_driver);

MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
MODULE_DESCRIPTION("Loongson1 GPIO driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
bd37c999 KC	1	/*
	2	* GPIO Driver for Loongson 1 SoC
	3	*
	4	* Copyright (C) 2015-2016 Zhang, Keguang <keguang.zhang@gmail.com>
	5	*
	6	* This file is licensed under the terms of the GNU General Public
	7	* License version 2. This program is licensed "as is" without any
	8	* warranty of any kind, whether express or implied.
	9	*/
	10
5f604506	11	#include <linux/module.h>
bd37c999 KC	12	#include <linux/gpio/driver.h>
bd37c999 KC	13	#include <linux/platform_device.h>
fe29416b	14	#include <linux/bitops.h>
bd37c999 KC	15
	16	/* Loongson 1 GPIO Register Definitions */
	17	#define GPIO_CFG 0x0
	18	#define GPIO_DIR 0x10
	19	#define GPIO_DATA 0x20
	20	#define GPIO_OUTPUT 0x30
	21
	22	static void __iomem *gpio_reg_base;
	23
	24	static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
	25	{
bd37c999 KC	26	unsigned long flags;
	27
	28	spin_lock_irqsave(&gc->bgpio_lock, flags);
fe29416b	29	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) \| BIT(offset),
bd37c999 KC	30	gpio_reg_base + GPIO_CFG);
	31	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
	32
	33	return 0;
	34	}
	35
	36	static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
	37	{
bd37c999 KC	38	unsigned long flags;
	39
	40	spin_lock_irqsave(&gc->bgpio_lock, flags);
fe29416b	41	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
bd37c999 KC	42	gpio_reg_base + GPIO_CFG);
	43	spin_unlock_irqrestore(&gc->bgpio_lock, flags);
	44	}
	45
	46	static int ls1x_gpio_probe(struct platform_device *pdev)
	47	{
	48	struct device *dev = &pdev->dev;
	49	struct gpio_chip *gc;
	50	struct resource *res;
	51	int ret;
	52
	53	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
	54	if (!gc)
	55	return -ENOMEM;
	56
	57	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
bd37c999 KC	58	gpio_reg_base = devm_ioremap_resource(dev, res);
	59	if (IS_ERR(gpio_reg_base))
	60	return PTR_ERR(gpio_reg_base);
	61
	62	ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA,
	63	gpio_reg_base + GPIO_OUTPUT, NULL,
	64	NULL, gpio_reg_base + GPIO_DIR, 0);
	65	if (ret)
	66	goto err;
	67
	68	gc->owner = THIS_MODULE;
	69	gc->request = ls1x_gpio_request;
	70	gc->free = ls1x_gpio_free;
	71	gc->base = pdev->id * 32;
	72
	73	ret = devm_gpiochip_add_data(dev, gc, NULL);
	74	if (ret)
	75	goto err;
	76
	77	platform_set_drvdata(pdev, gc);
	78	dev_info(dev, "Loongson1 GPIO driver registered\n");
	79
	80	return 0;
	81	err:
	82	dev_err(dev, "failed to register GPIO device\n");
	83	return ret;
	84	}
	85
	86	static struct platform_driver ls1x_gpio_driver = {
	87	.probe = ls1x_gpio_probe,
	88	.driver = {
	89	.name = "ls1x-gpio",
	90	},
	91	};
	92
	93	module_platform_driver(ls1x_gpio_driver);
	94
	95	MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>");
	96	MODULE_DESCRIPTION("Loongson1 GPIO driver");
	97	MODULE_LICENSE("GPL");