drivers/gpio/mxc_gpio.c

   1 /*
   2  * Copyright (C) 2009
   3  * Guennadi Liakhovetski, DENX Software Engineering, <lg@denx.de>
   4  *
   5  * Copyright (C) 2011
   6  * Stefano Babic, DENX Software Engineering, <sbabic@denx.de>
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10 #include <common.h>
  11 #include <asm/arch/imx-regs.h>
  12 #include <asm/gpio.h>
  13 #include <asm/io.h>
  14 #include <errno.h>
  15
  16 enum mxc_gpio_direction {
  17         MXC_GPIO_DIRECTION_IN,
  18         MXC_GPIO_DIRECTION_OUT,
  19 };
  20
  21 #define GPIO_TO_PORT(n)         (n / 32)
  22
  23 /* GPIO port description */
  24 static unsigned long gpio_ports[] = {
  25         [0] = GPIO1_BASE_ADDR,
  26         [1] = GPIO2_BASE_ADDR,
  27         [2] = GPIO3_BASE_ADDR,
  28 #if defined(CONFIG_MX25) || defined(CONFIG_MX27) || defined(CONFIG_MX51) || \
  29                 defined(CONFIG_MX53) || defined(CONFIG_MX6)
  30         [3] = GPIO4_BASE_ADDR,
  31 #endif
  32 #if defined(CONFIG_MX27) || defined(CONFIG_MX53) || defined(CONFIG_MX6)
  33         [4] = GPIO5_BASE_ADDR,
  34         [5] = GPIO6_BASE_ADDR,
  35 #endif
  36 #if defined(CONFIG_MX53) || defined(CONFIG_MX6)
  37         [6] = GPIO7_BASE_ADDR,
  38 #endif
  39 };
  40
  41 static int mxc_gpio_direction(unsigned int gpio,
  42         enum mxc_gpio_direction direction)
  43 {
  44         unsigned int port = GPIO_TO_PORT(gpio);
  45         struct gpio_regs *regs;
  46         u32 l;
  47
  48         if (port >= ARRAY_SIZE(gpio_ports))
  49                 return -1;
  50
  51         gpio &= 0x1f;
  52
  53         regs = (struct gpio_regs *)gpio_ports[port];
  54
  55         l = readl(&regs->gpio_dir);
  56
  57         switch (direction) {
  58         case MXC_GPIO_DIRECTION_OUT:
  59                 l |= 1 << gpio;
  60                 break;
  61         case MXC_GPIO_DIRECTION_IN:
  62                 l &= ~(1 << gpio);
  63         }
  64         writel(l, &regs->gpio_dir);
  65
  66         return 0;
  67 }
  68
  69 int gpio_set_value(unsigned gpio, int value)
  70 {
  71         unsigned int port = GPIO_TO_PORT(gpio);
  72         struct gpio_regs *regs;
  73         u32 l;
  74
  75         if (port >= ARRAY_SIZE(gpio_ports))
  76                 return -1;
  77
  78         gpio &= 0x1f;
  79
  80         regs = (struct gpio_regs *)gpio_ports[port];
  81
  82         l = readl(&regs->gpio_dr);
  83         if (value)
  84                 l |= 1 << gpio;
  85         else
  86                 l &= ~(1 << gpio);
  87         writel(l, &regs->gpio_dr);
  88
  89         return 0;
  90 }
  91
  92 int gpio_get_value(unsigned gpio)
  93 {
  94         unsigned int port = GPIO_TO_PORT(gpio);
  95         struct gpio_regs *regs;
  96         u32 val;
  97
  98         if (port >= ARRAY_SIZE(gpio_ports))
  99                 return -1;
 100
 101         gpio &= 0x1f;
 102
 103         regs = (struct gpio_regs *)gpio_ports[port];
 104
 105         val = (readl(&regs->gpio_psr) >> gpio) & 0x01;
 106
 107         return val;
 108 }
 109
 110 int gpio_request(unsigned gpio, const char *label)
 111 {
 112         unsigned int port = GPIO_TO_PORT(gpio);
 113         if (port >= ARRAY_SIZE(gpio_ports))
 114                 return -1;
 115         return 0;
 116 }
 117
 118 int gpio_free(unsigned gpio)
 119 {
 120         return 0;
 121 }
 122
 123 int gpio_direction_input(unsigned gpio)
 124 {
 125         return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_IN);
 126 }
 127
 128 int gpio_direction_output(unsigned gpio, int value)
 129 {
 130         int ret = gpio_set_value(gpio, value);
 131
 132         if (ret < 0)
 133                 return ret;
 134
 135         return mxc_gpio_direction(gpio, MXC_GPIO_DIRECTION_OUT);
 136 }