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 = NULL; 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 if (IS_ERR_VALUE(value)) 227 printf("unknown (ret=%d)\n", value); 228 else 229 printf("%d\n", value); 230 if (sub_cmd != GPIOC_INPUT && !IS_ERR_VALUE(value)) { 231 int nval = gpio_get_value(gpio); 232 233 if (IS_ERR_VALUE(nval)) 234 printf(" Warning: no access to GPIO output value\n"); 235 else if (nval != value) 236 printf(" Warning: value of pin is still %d\n", nval); 237 } 238 239 if (ret != -EBUSY) 240 gpio_free(gpio); 241 242 return value; 243 } 244 245 U_BOOT_CMD(gpio, 4, 0, do_gpio, 246 "query and control gpio pins", 247 "<input|set|clear|toggle> <pin>\n" 248 " - input/set/clear/toggle the specified pin\n" 249 "gpio status [-a] [<bank> | <pin>] - show [all/claimed] GPIOs"); 250