xref: /openbmc/u-boot/cmd/gpio.c (revision 85ab0452)
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 	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 
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 
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 
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