xref: /openbmc/u-boot/cmd/gpio.c (revision 9e3c0174da842dd88f5feaffbf843ba332233897)
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 %u) 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