drivers/gpio/gpio-moxart.c

   1 /*
   2  * MOXA ART SoCs GPIO driver.
   3  *
   4  * Copyright (C) 2013 Jonas Jensen
   5  *
   6  * Jonas Jensen <jonas.jensen@gmail.com>
   7  *
   8  * This file is licensed under the terms of the GNU General Public
   9  * License version 2.  This program is licensed "as is" without any
  10  * warranty of any kind, whether express or implied.
  11  */
  12
  13 #include <linux/err.h>
  14 #include <linux/init.h>
  15 #include <linux/irq.h>
  16 #include <linux/io.h>
  17 #include <linux/gpio.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/module.h>
  20 #include <linux/of_address.h>
  21 #include <linux/of_gpio.h>
  22 #include <linux/pinctrl/consumer.h>
  23 #include <linux/delay.h>
  24 #include <linux/timer.h>
  25 #include <linux/bitops.h>
  26 #include <linux/basic_mmio_gpio.h>
  27
  28 #define GPIO_DATA_OUT           0x00
  29 #define GPIO_DATA_IN            0x04
  30 #define GPIO_PIN_DIRECTION      0x08
  31
  32 static int moxart_gpio_probe(struct platform_device *pdev)
  33 {
  34         struct device *dev = &pdev->dev;
  35         struct resource *res;
  36         struct bgpio_chip *bgc;
  37         void __iomem *base;
  38         int ret;
  39
  40         bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL);
  41         if (!bgc)
  42                 return -ENOMEM;
  43
  44         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  45         base = devm_ioremap_resource(dev, res);
  46         if (IS_ERR(base))
  47                 return PTR_ERR(base);
  48
  49         ret = bgpio_init(bgc, dev, 4, base + GPIO_DATA_IN,
  50                          base + GPIO_DATA_OUT, NULL,
  51                          base + GPIO_PIN_DIRECTION, NULL,
  52                          BGPIOF_READ_OUTPUT_REG_SET);
  53         if (ret) {
  54                 dev_err(&pdev->dev, "bgpio_init failed\n");
  55                 return ret;
  56         }
  57
  58         bgc->gc.label = "moxart-gpio";
  59         bgc->gc.request = gpiochip_generic_request;
  60         bgc->gc.free = gpiochip_generic_free;
  61         bgc->data = bgc->read_reg(bgc->reg_set);
  62         bgc->gc.base = 0;
  63         bgc->gc.ngpio = 32;
  64         bgc->gc.dev = dev;
  65         bgc->gc.owner = THIS_MODULE;
  66
  67         ret = gpiochip_add(&bgc->gc);
  68         if (ret) {
  69                 dev_err(dev, "%s: gpiochip_add failed\n",
  70                         dev->of_node->full_name);
  71                 return ret;
  72         }
  73
  74         return ret;
  75 }
  76
  77 static const struct of_device_id moxart_gpio_match[] = {
  78         { .compatible = "moxa,moxart-gpio" },
  79         { }
  80 };
  81
  82 static struct platform_driver moxart_gpio_driver = {
  83         .driver = {
  84                 .name           = "moxart-gpio",
  85                 .of_match_table = moxart_gpio_match,
  86         },
  87         .probe  = moxart_gpio_probe,
  88 };
  89 module_platform_driver(moxart_gpio_driver);
  90
  91 MODULE_DESCRIPTION("MOXART GPIO chip driver");
  92 MODULE_LICENSE("GPL");
  93 MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");