Eric Lee / smarc-fsl-linux-kernel

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drivers/gpio/gpio-loongson1.c 2.27 KB
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bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  /*
   * 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.
   */
5f604506f   Paul Gortmaker   gpio: loongson1: ... 
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  #include <linux/module.h>
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  #include <linux/gpio/driver.h>
  #include <linux/platform_device.h>
fe29416b5   Linus Walleij   gpio: loongson1: ... 
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  #include <linux/bitops.h>
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  /* 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)
  {
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  	unsigned long flags;
  
  	spin_lock_irqsave(&gc->bgpio_lock, flags);
fe29416b5   Linus Walleij   gpio: loongson1: ... 
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  	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) | BIT(offset),
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  		     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)
  {
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  	unsigned long flags;
  
  	spin_lock_irqsave(&gc->bgpio_lock, flags);
fe29416b5   Linus Walleij   gpio: loongson1: ... 
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  	__raw_writel(__raw_readl(gpio_reg_base + GPIO_CFG) & ~BIT(offset),
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  		     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;
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  	int ret;
  
  	gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
  	if (!gc)
  		return -ENOMEM;
62fe072a2   Enrico Weigelt, metux IT consult   drivers: gpio: lo... 
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  	gpio_reg_base = devm_platform_ioremap_resource(pdev, 0);
bd37c999c   Kelvin Cheung   gpio: Loongson1: ... 
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  	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
  ");
  
  	return 0;
  err:
  	dev_err(dev, "failed to register GPIO device
  ");
  	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");