projects / linux-2.6-block.git / blame
| 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> |
| 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; | |
| bd37c999 KC |
50 | int ret; |
| 51 | ||
| 52 | gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL); | |
| 53 | if (!gc) | |
| 54 | return -ENOMEM; | |
| 55 | ||
| 62fe072a | 56 | gpio_reg_base = devm_platform_ioremap_resource(pdev, 0); |
| bd37c999 KC |
57 | if (IS_ERR(gpio_reg_base)) |
| 58 | return PTR_ERR(gpio_reg_base); | |
| 59 | ||
| 60 | ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA, | |
| 61 | gpio_reg_base + GPIO_OUTPUT, NULL, | |
| 62 | NULL, gpio_reg_base + GPIO_DIR, 0); | |
| 63 | if (ret) | |
| 64 | goto err; | |
| 65 | ||
| 66 | gc->owner = THIS_MODULE; | |
| 67 | gc->request = ls1x_gpio_request; | |
| 68 | gc->free = ls1x_gpio_free; | |
| 69 | gc->base = pdev->id * 32; | |
| 70 | ||
| 71 | ret = devm_gpiochip_add_data(dev, gc, NULL); | |
| 72 | if (ret) | |
| 73 | goto err; | |
| 74 | ||
| 75 | platform_set_drvdata(pdev, gc); | |
| 76 | dev_info(dev, "Loongson1 GPIO driver registered\n"); | |
| 77 | ||
| 78 | return 0; | |
| 79 | err: | |
| 80 | dev_err(dev, "failed to register GPIO device\n"); | |
| 81 | return ret; | |
| 82 | } | |
| 83 | ||
| 84 | static struct platform_driver ls1x_gpio_driver = { | |
| 85 | .probe = ls1x_gpio_probe, | |
| 86 | .driver = { | |
| 87 | .name = "ls1x-gpio", | |
| 88 | }, | |
| 89 | }; | |
| 90 | ||
| 91 | module_platform_driver(ls1x_gpio_driver); | |
| 92 | ||
| 93 | MODULE_AUTHOR("Kelvin Cheung <keguang.zhang@gmail.com>"); | |
| 94 | MODULE_DESCRIPTION("Loongson1 GPIO driver"); | |
| 95 | MODULE_LICENSE("GPL"); |