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95 lines
2.3 KiB
95 lines
2.3 KiB
/* |
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* GPIO Driver for Loongson 1 SoC |
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* |
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* Copyright (C) 2015-2016 Zhang, Keguang <[email protected]> |
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* |
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* This file is licensed under the terms of the GNU General Public |
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* License version 2. This program is licensed "as is" without any |
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* warranty of any kind, whether express or implied. |
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*/ |
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#include <linux/module.h> |
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#include <linux/gpio/driver.h> |
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#include <linux/platform_device.h> |
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#include <linux/bitops.h> |
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/* Loongson 1 GPIO Register Definitions */ |
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#define GPIO_CFG 0x0 |
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#define GPIO_DIR 0x10 |
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#define GPIO_DATA 0x20 |
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#define GPIO_OUTPUT 0x30 |
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static void __iomem *gpio_reg_base; |
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static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset) |
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{ |
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unsigned long flags; |
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spin_lock_irqsave(&gc->bgpio_lock, flags); |
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__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset), |
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gpio_reg_base + GPIO_CFG); |
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spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
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return 0; |
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} |
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static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset) |
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{ |
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unsigned long flags; |
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spin_lock_irqsave(&gc->bgpio_lock, flags); |
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__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset), |
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gpio_reg_base + GPIO_CFG); |
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spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
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} |
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static int ls1x_gpio_probe(struct platform_device *pdev) |
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{ |
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struct device *dev = &pdev->dev; |
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struct gpio_chip *gc; |
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int ret; |
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gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL); |
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if (!gc) |
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return -ENOMEM; |
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gpio_reg_base = devm_platform_ioremap_resource(pdev, 0); |
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if (IS_ERR(gpio_reg_base)) |
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return PTR_ERR(gpio_reg_base); |
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ret = bgpio_init(gc, dev, 4, gpio_reg_base + GPIO_DATA, |
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gpio_reg_base + GPIO_OUTPUT, NULL, |
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NULL, gpio_reg_base + GPIO_DIR, 0); |
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if (ret) |
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goto err; |
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gc->owner = THIS_MODULE; |
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gc->request = ls1x_gpio_request; |
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gc->free = ls1x_gpio_free; |
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gc->base = pdev->id * 32; |
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ret = devm_gpiochip_add_data(dev, gc, NULL); |
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if (ret) |
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goto err; |
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platform_set_drvdata(pdev, gc); |
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dev_info(dev, "Loongson1 GPIO driver registered\n"); |
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return 0; |
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err: |
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dev_err(dev, "failed to register GPIO device\n"); |
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return ret; |
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} |
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static struct platform_driver ls1x_gpio_driver = { |
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.probe = ls1x_gpio_probe, |
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.driver = { |
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.name = "ls1x-gpio", |
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}, |
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}; |
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module_platform_driver(ls1x_gpio_driver); |
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MODULE_AUTHOR("Kelvin Cheung <[email protected]>"); |
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MODULE_DESCRIPTION("Loongson1 GPIO driver"); |
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MODULE_LICENSE("GPL");
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