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
name_to_gpio(const char * name)15 __weak int name_to_gpio(const char *name)
16 {
17 return simple_strtoul(name, NULL, 10);
18 }
19
20 enum gpio_cmd {
21 GPIO_INPUT,
22 GPIO_SET,
23 GPIO_CLEAR,
24 GPIO_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
gpio_get_description(struct udevice * dev,const char * bank_name,int offset,int * flagsp)36 static void gpio_get_description(struct udevice *dev, const char *bank_name,
37 int offset, int *flagsp)
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 (!(*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
do_gpio_status(bool all,const char * gpio_name)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 !strncmp(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);
102 } else {
103 for (offset = 0; offset < num_bits; offset++) {
104 gpio_get_description(dev, bank_name,
105 offset, &flags);
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
do_gpio(cmd_tbl_t * cmdtp,int flag,int argc,char * const argv[])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': sub_cmd = GPIO_INPUT; break;
162 case 's': sub_cmd = GPIO_SET; break;
163 case 'c': sub_cmd = GPIO_CLEAR; break;
164 case 't': sub_cmd = GPIO_TOGGLE; break;
165 default: goto show_usage;
166 }
167
168 #if defined(CONFIG_DM_GPIO)
169 /*
170 * TODO(sjg@chromium.org): For now we must fit into the existing GPIO
171 * framework, so we look up the name here and convert it to a GPIO number.
172 * Once all GPIO drivers are converted to driver model, we can change the
173 * code here to use the GPIO uclass interface instead of the numbered
174 * GPIO compatibility layer.
175 */
176 ret = gpio_lookup_name(str_gpio, NULL, NULL, &gpio);
177 if (ret) {
178 printf("GPIO: '%s' not found\n", str_gpio);
179 return cmd_process_error(cmdtp, ret);
180 }
181 #else
182 /* turn the gpio name into a gpio number */
183 gpio = name_to_gpio(str_gpio);
184 if (gpio < 0)
185 goto show_usage;
186 #endif
187 /* grab the pin before we tweak it */
188 ret = gpio_request(gpio, "cmd_gpio");
189 if (ret && ret != -EBUSY) {
190 printf("gpio: requesting pin %u failed\n", gpio);
191 return -1;
192 }
193
194 /* finally, let's do it: set direction and exec command */
195 if (sub_cmd == GPIO_INPUT) {
196 gpio_direction_input(gpio);
197 value = gpio_get_value(gpio);
198 } else {
199 switch (sub_cmd) {
200 case GPIO_SET:
201 value = 1;
202 break;
203 case GPIO_CLEAR:
204 value = 0;
205 break;
206 case GPIO_TOGGLE:
207 value = gpio_get_value(gpio);
208 if (!IS_ERR_VALUE(value))
209 value = !value;
210 break;
211 default:
212 goto show_usage;
213 }
214 gpio_direction_output(gpio, value);
215 }
216 printf("gpio: pin %s (gpio %i) value is ", str_gpio, gpio);
217 if (IS_ERR_VALUE(value))
218 printf("unknown (ret=%d)\n", value);
219 else
220 printf("%d\n", value);
221 if (sub_cmd != GPIO_INPUT && !IS_ERR_VALUE(value)) {
222 int nval = gpio_get_value(gpio);
223
224 if (IS_ERR_VALUE(nval))
225 printf(" Warning: no access to GPIO output value\n");
226 else if (nval != value)
227 printf(" Warning: value of pin is still %d\n", nval);
228 }
229
230 if (ret != -EBUSY)
231 gpio_free(gpio);
232
233 return value;
234 }
235
236 U_BOOT_CMD(gpio, 4, 0, do_gpio,
237 "query and control gpio pins",
238 "<input|set|clear|toggle> <pin>\n"
239 " - input/set/clear/toggle the specified pin\n"
240 "gpio status [-a] [<bank> | <pin>] - show [all/claimed] GPIOs");
241