cmd/gpio.c

   1 /*
   2  * Control GPIO pins on the fly
   3  *
   4  * Copyright (c) 2008-2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <common.h>
  10 #include <command.h>
  11 #include <errno.h>
  12 #include <dm.h>
  13 #include <asm/gpio.h>
  14
  15 __weak int name_to_gpio(const char *name)
  16 {
  17         return simple_strtoul(name, NULL, 10);
  18 }
  19
  20 enum gpio_cmd {
  21         GPIOC_INPUT,
  22         GPIOC_SET,
  23         GPIOC_CLEAR,
  24         GPIOC_TOGGLE,
  25 };
  26
  27 #if defined(CONFIG_DM_GPIO) && !defined(gpio_status)
  28
  29 /* A few flags used by show_gpio() */
  30 enum {
  31         FLAG_SHOW_ALL           = 1 << 0,
  32         FLAG_SHOW_BANK          = 1 << 1,
  33         FLAG_SHOW_NEWLINE       = 1 << 2,
  34 };
  35
  36 static void gpio_get_description(struct udevice *dev, const char *bank_name,
  37                                  int offset, int *flagsp, bool show_all)
  38 {
  39         char buf[80];
  40         int ret;
  41
  42         ret = gpio_get_function(dev, offset, NULL);
  43         if (ret < 0)
  44                 goto err;
  45         if (!show_all && !(*flagsp & FLAG_SHOW_ALL) && ret == GPIOF_UNUSED)
  46                 return;
  47         if ((*flagsp & FLAG_SHOW_BANK) && bank_name) {
  48                 if (*flagsp & FLAG_SHOW_NEWLINE) {
  49                         putc('\n');
  50                         *flagsp &= ~FLAG_SHOW_NEWLINE;
  51                 }
  52                 printf("Bank %s:\n", bank_name);
  53                 *flagsp &= ~FLAG_SHOW_BANK;
  54         }
  55
  56         ret = gpio_get_status(dev, offset, buf, sizeof(buf));
  57         if (ret)
  58                 goto err;
  59
  60         printf("%s\n", buf);
  61         return;
  62 err:
  63         printf("Error %d\n", ret);
  64 }
  65
  66 static int do_gpio_status(bool all, const char *gpio_name)
  67 {
  68         struct udevice *dev;
  69         int banklen;
  70         int flags;
  71         int ret;
  72
  73         flags = 0;
  74         if (gpio_name && !*gpio_name)
  75                 gpio_name = NULL;
  76         for (ret = uclass_first_device(UCLASS_GPIO, &dev);
  77              dev;
  78              ret = uclass_next_device(&dev)) {
  79                 const char *bank_name;
  80                 int num_bits;
  81
  82                 flags |= FLAG_SHOW_BANK;
  83                 if (all)
  84                         flags |= FLAG_SHOW_ALL;
  85                 bank_name = gpio_get_bank_info(dev, &num_bits);
  86                 if (!num_bits) {
  87                         debug("GPIO device %s has no bits\n", dev->name);
  88                         continue;
  89                 }
  90                 banklen = bank_name ? strlen(bank_name) : 0;
  91
  92                 if (!gpio_name || !bank_name ||
  93                     !strncasecmp(gpio_name, bank_name, banklen)) {
  94                         const char *p;
  95                         int offset;
  96
  97                         p = gpio_name + banklen;
  98                         if (gpio_name && *p) {
  99                                 offset = simple_strtoul(p, NULL, 10);
 100                                 gpio_get_description(dev, bank_name, offset,
 101                                                      &flags, true);
 102                         } else {
 103                                 for (offset = 0; offset < num_bits; offset++) {
 104                                         gpio_get_description(dev, bank_name,
 105                                                      offset, &flags, false);
 106                                 }
 107                         }
 108                 }
 109                 /* Add a newline between bank names */
 110                 if (!(flags & FLAG_SHOW_BANK))
 111                         flags |= FLAG_SHOW_NEWLINE;
 112         }
 113
 114         return ret;
 115 }
 116 #endif
 117
 118 static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 119 {
 120         unsigned int gpio;
 121         enum gpio_cmd sub_cmd;
 122         int value;
 123         const char *str_cmd, *str_gpio = NULL;
 124         int ret;
 125 #ifdef CONFIG_DM_GPIO
 126         bool all = false;
 127 #endif
 128
 129         if (argc < 2)
 130  show_usage:
 131                 return CMD_RET_USAGE;
 132         str_cmd = argv[1];
 133         argc -= 2;
 134         argv += 2;
 135 #ifdef CONFIG_DM_GPIO
 136         if (argc > 0 && !strcmp(*argv, "-a")) {
 137                 all = true;
 138                 argc--;
 139                 argv++;
 140         }
 141 #endif
 142         if (argc > 0)
 143                 str_gpio = *argv;
 144         if (!strncmp(str_cmd, "status", 2)) {
 145                 /* Support deprecated gpio_status() */
 146 #ifdef gpio_status
 147                 gpio_status();
 148                 return 0;
 149 #elif defined(CONFIG_DM_GPIO)
 150                 return cmd_process_error(cmdtp, do_gpio_status(all, str_gpio));
 151 #else
 152                 goto show_usage;
 153 #endif
 154         }
 155
 156         if (!str_gpio)
 157                 goto show_usage;
 158
 159         /* parse the behavior */
 160         switch (*str_cmd) {
 161         case 'i':
 162                 sub_cmd = GPIOC_INPUT;
 163                 break;
 164         case 's':
 165                 sub_cmd = GPIOC_SET;
 166                 break;
 167         case 'c':
 168                 sub_cmd = GPIOC_CLEAR;
 169                 break;
 170         case 't':
 171                 sub_cmd = GPIOC_TOGGLE;
 172                 break;
 173         default:
 174                 goto show_usage;
 175         }
 176
 177 #if defined(CONFIG_DM_GPIO)
 178         /*
 179          * TODO(sjg@chromium.org): For now we must fit into the existing GPIO
 180          * framework, so we look up the name here and convert it to a GPIO number.
 181          * Once all GPIO drivers are converted to driver model, we can change the
 182          * code here to use the GPIO uclass interface instead of the numbered
 183          * GPIO compatibility layer.
 184          */
 185         ret = gpio_lookup_name(str_gpio, NULL, NULL, &gpio);
 186         if (ret) {
 187                 printf("GPIO: '%s' not found\n", str_gpio);
 188                 return cmd_process_error(cmdtp, ret);
 189         }
 190 #else
 191         /* turn the gpio name into a gpio number */
 192         gpio = name_to_gpio(str_gpio);
 193         if (gpio < 0)
 194                 goto show_usage;
 195 #endif
 196         /* grab the pin before we tweak it */
 197         ret = gpio_request(gpio, "cmd_gpio");
 198         if (ret && ret != -EBUSY) {
 199                 printf("gpio: requesting pin %u failed\n", gpio);
 200                 return -1;
 201         }
 202
 203         /* finally, let's do it: set direction and exec command */
 204         if (sub_cmd == GPIOC_INPUT) {
 205                 gpio_direction_input(gpio);
 206                 value = gpio_get_value(gpio);
 207         } else {
 208                 switch (sub_cmd) {
 209                 case GPIOC_SET:
 210                         value = 1;
 211                         break;
 212                 case GPIOC_CLEAR:
 213                         value = 0;
 214                         break;
 215                 case GPIOC_TOGGLE:
 216                         value = gpio_get_value(gpio);
 217                         if (!IS_ERR_VALUE(value))
 218                                 value = !value;
 219                         break;
 220                 default:
 221                         goto show_usage;
 222                 }
 223                 gpio_direction_output(gpio, value);
 224         }
 225         printf("gpio: pin %s (gpio %u) value is ", str_gpio, gpio);
 226
 227         if (IS_ERR_VALUE(value)) {
 228                 printf("unknown (ret=%d)\n", value);
 229                 goto err;
 230         } else {
 231                 printf("%d\n", value);
 232         }
 233
 234         if (sub_cmd != GPIOC_INPUT && !IS_ERR_VALUE(value)) {
 235                 int nval = gpio_get_value(gpio);
 236
 237                 if (IS_ERR_VALUE(nval)) {
 238                         printf("   Warning: no access to GPIO output value\n");
 239                         goto err;
 240                 } else if (nval != value) {
 241                         printf("   Warning: value of pin is still %d\n", nval);
 242                         goto err;
 243                 }
 244         }
 245
 246         if (ret != -EBUSY)
 247                 gpio_free(gpio);
 248
 249         return CMD_RET_SUCCESS;
 250
 251 err:
 252         if (ret != -EBUSY)
 253                 gpio_free(gpio);
 254         return CMD_RET_FAILURE;
 255 }
 256
 257 U_BOOT_CMD(gpio, 4, 0, do_gpio,
 258            "query and control gpio pins",
 259            "<input|set|clear|toggle> <pin>\n"
 260            "    - input/set/clear/toggle the specified pin\n"
 261            "gpio status [-a] [<bank> | <pin>]  - show [all/claimed] GPIOs");