99 lines
2.4 KiB
C
99 lines
2.4 KiB
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>
|
|
|
|
/* 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 pinmask = gc->pin2mask(gc, offset);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&gc->bgpio_lock, flags);
|
|
__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | pinmask,
|
|
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 pinmask = gc->pin2mask(gc, offset);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&gc->bgpio_lock, flags);
|
|
__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~pinmask,
|
|
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");
|