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
72 flags = 0;
73 if (gpio_name && !*gpio_name)
74 gpio_name = NULL;
75 for (uclass_first_device(UCLASS_GPIO, &dev);
76 dev;
77 uclass_next_device(&dev)) {
78 const char *bank_name;
79 int num_bits;
80
81 flags |= FLAG_SHOW_BANK;
82 if (all)
83 flags |= FLAG_SHOW_ALL;
84 bank_name = gpio_get_bank_info(dev, &num_bits);
85 if (!num_bits) {
86 debug("GPIO device %s has no bits\n", dev->name);
87 continue;
88 }
89 banklen = bank_name ? strlen(bank_name) : 0;
90
91 if (!gpio_name || !bank_name ||
92 !strncmp(gpio_name, bank_name, banklen)) {
93 const char *p = NULL;
94 int offset;
95
96 p = gpio_name + banklen;
97 if (gpio_name && *p) {
98 offset = simple_strtoul(p, NULL, 10);
99 gpio_get_description(dev, bank_name, offset,
100 &flags);
101 } else {
102 for (offset = 0; offset < num_bits; offset++) {
103 gpio_get_description(dev, bank_name,
104 offset, &flags);
105 }
106 }
107 }
108 /* Add a newline between bank names */
109 if (!(flags & FLAG_SHOW_BANK))
110 flags |= FLAG_SHOW_NEWLINE;
111 }
112
113 return 0;
114 }
115 #endif
116
do_gpio(cmd_tbl_t * cmdtp,int flag,int argc,char * const argv[])117 static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
118 {
119 unsigned int gpio;
120 enum gpio_cmd sub_cmd;
121 int value;
122 const char *str_cmd, *str_gpio = NULL;
123 int ret;
124 #ifdef CONFIG_DM_GPIO
125 bool all = false;
126 #endif
127
128 if (argc < 2)
129 show_usage:
130 return CMD_RET_USAGE;
131 str_cmd = argv[1];
132 argc -= 2;
133 argv += 2;
134 #ifdef CONFIG_DM_GPIO
135 if (argc > 0 && !strcmp(*argv, "-a")) {
136 all = true;
137 argc--;
138 argv++;
139 }
140 #endif
141 if (argc > 0)
142 str_gpio = *argv;
143 if (!strncmp(str_cmd, "status", 2)) {
144 /* Support deprecated gpio_status() */
145 #ifdef gpio_status
146 gpio_status();
147 return 0;
148 #elif defined(CONFIG_DM_GPIO)
149 return cmd_process_error(cmdtp, do_gpio_status(all, str_gpio));
150 #else
151 goto show_usage;
152 #endif
153 }
154
155 if (!str_gpio)
156 goto show_usage;
157
158 /* parse the behavior */
159 switch (*str_cmd) {
160 case 'i': sub_cmd = GPIO_INPUT; break;
161 case 's': sub_cmd = GPIO_SET; break;
162 case 'c': sub_cmd = GPIO_CLEAR; break;
163 case 't': sub_cmd = GPIO_TOGGLE; break;
164 default: goto show_usage;
165 }
166
167 #if defined(CONFIG_DM_GPIO)
168 /*
169 * TODO(sjg@chromium.org): For now we must fit into the existing GPIO
170 * framework, so we look up the name here and convert it to a GPIO number.
171 * Once all GPIO drivers are converted to driver model, we can change the
172 * code here to use the GPIO uclass interface instead of the numbered
173 * GPIO compatibility layer.
174 */
175 ret = gpio_lookup_name(str_gpio, NULL, NULL, &gpio);
176 if (ret) {
177 printf("GPIO: '%s' not found\n", str_gpio);
178 return cmd_process_error(cmdtp, ret);
179 }
180 #else
181 /* turn the gpio name into a gpio number */
182 gpio = name_to_gpio(str_gpio);
183 if (gpio < 0)
184 goto show_usage;
185 #endif
186 /* grab the pin before we tweak it */
187 ret = gpio_request(gpio, "cmd_gpio");
188 if (ret && ret != -EBUSY) {
189 printf("gpio: requesting pin %u failed\n", gpio);
190 return -1;
191 }
192
193 /* finally, let's do it: set direction and exec command */
194 if (sub_cmd == GPIO_INPUT) {
195 gpio_direction_input(gpio);
196 value = gpio_get_value(gpio);
197 } else {
198 switch (sub_cmd) {
199 case GPIO_SET:
200 value = 1;
201 break;
202 case GPIO_CLEAR:
203 value = 0;
204 break;
205 case GPIO_TOGGLE:
206 value = gpio_get_value(gpio);
207 if (!IS_ERR_VALUE(value))
208 value = !value;
209 break;
210 default:
211 goto show_usage;
212 }
213 gpio_direction_output(gpio, value);
214 }
215 printf("gpio: pin %s (gpio %i) value is ", str_gpio, gpio);
216 if (IS_ERR_VALUE(value))
217 printf("unknown (ret=%d)\n", value);
218 else
219 printf("%d\n", value);
220 if (sub_cmd != GPIO_INPUT && !IS_ERR_VALUE(value)) {
221 int nval = gpio_get_value(gpio);
222
223 if (IS_ERR_VALUE(nval))
224 printf(" Warning: no access to GPIO output value\n");
225 else if (nval != value)
226 printf(" Warning: value of pin is still %d\n", nval);
227 }
228
229 if (ret != -EBUSY)
230 gpio_free(gpio);
231
232 return value;
233 }
234
235 U_BOOT_CMD(gpio, 4, 0, do_gpio,
236 "query and control gpio pins",
237 "<input|set|clear|toggle> <pin>\n"
238 " - input/set/clear/toggle the specified pin\n"
239 "gpio status [-a] [<bank> | <pin>] - show [all/claimed] GPIOs");
240