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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * GPIO Driver for Loongson 1 SoC4 *5 * Copyright (C) 2015-2023 Keguang Zhang <keguang.zhang@gmail.com>6 */7 8#include <linux/module.h>9#include <linux/gpio/driver.h>10#include <linux/platform_device.h>11#include <linux/bitops.h>12 13/* Loongson 1 GPIO Register Definitions */14#define GPIO_CFG 0x015#define GPIO_DIR 0x1016#define GPIO_DATA 0x2017#define GPIO_OUTPUT 0x3018 19struct ls1x_gpio_chip {20 struct gpio_chip gc;21 void __iomem *reg_base;22};23 24static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)25{26 struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);27 unsigned long flags;28 29 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);30 __raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) | BIT(offset),31 ls1x_gc->reg_base + GPIO_CFG);32 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);33 34 return 0;35}36 37static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)38{39 struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);40 unsigned long flags;41 42 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);43 __raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) & ~BIT(offset),44 ls1x_gc->reg_base + GPIO_CFG);45 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);46}47 48static int ls1x_gpio_probe(struct platform_device *pdev)49{50 struct device *dev = &pdev->dev;51 struct ls1x_gpio_chip *ls1x_gc;52 int ret;53 54 ls1x_gc = devm_kzalloc(dev, sizeof(*ls1x_gc), GFP_KERNEL);55 if (!ls1x_gc)56 return -ENOMEM;57 58 ls1x_gc->reg_base = devm_platform_ioremap_resource(pdev, 0);59 if (IS_ERR(ls1x_gc->reg_base))60 return PTR_ERR(ls1x_gc->reg_base);61 62 ret = bgpio_init(&ls1x_gc->gc, dev, 4, ls1x_gc->reg_base + GPIO_DATA,63 ls1x_gc->reg_base + GPIO_OUTPUT, NULL,64 NULL, ls1x_gc->reg_base + GPIO_DIR, 0);65 if (ret)66 goto err;67 68 ls1x_gc->gc.owner = THIS_MODULE;69 ls1x_gc->gc.request = ls1x_gpio_request;70 ls1x_gc->gc.free = ls1x_gpio_free;71 /*72 * Clear ngpio to let gpiolib get the correct number73 * by reading ngpios property74 */75 ls1x_gc->gc.ngpio = 0;76 77 ret = devm_gpiochip_add_data(dev, &ls1x_gc->gc, ls1x_gc);78 if (ret)79 goto err;80 81 platform_set_drvdata(pdev, ls1x_gc);82 83 dev_info(dev, "GPIO controller registered with %d pins\n",84 ls1x_gc->gc.ngpio);85 86 return 0;87err:88 dev_err(dev, "failed to register GPIO controller\n");89 return ret;90}91 92static const struct of_device_id ls1x_gpio_dt_ids[] = {93 { .compatible = "loongson,ls1x-gpio" },94 { /* sentinel */ }95};96MODULE_DEVICE_TABLE(of, ls1x_gpio_dt_ids);97 98static struct platform_driver ls1x_gpio_driver = {99 .probe = ls1x_gpio_probe,100 .driver = {101 .name = "ls1x-gpio",102 .of_match_table = ls1x_gpio_dt_ids,103 },104};105 106module_platform_driver(ls1x_gpio_driver);107 108MODULE_AUTHOR("Keguang Zhang <keguang.zhang@gmail.com>");109MODULE_DESCRIPTION("Loongson1 GPIO driver");110MODULE_LICENSE("GPL");111