xref: /openbmc/linux/drivers/pinctrl/pinconf-generic.c (revision 840ef8b7cc584a23c4f9d05352f4dbaf8e56e5ab)
1 /*
2  * Core driver for the generic pin config portions of the pin control subsystem
3  *
4  * Copyright (C) 2011 ST-Ericsson SA
5  * Written on behalf of Linaro for ST-Ericsson
6  *
7  * Author: Linus Walleij <linus.walleij@linaro.org>
8  *
9  * License terms: GNU General Public License (GPL) version 2
10  */
11 
12 #define pr_fmt(fmt) "generic pinconfig core: " fmt
13 
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/device.h>
17 #include <linux/slab.h>
18 #include <linux/debugfs.h>
19 #include <linux/seq_file.h>
20 #include <linux/pinctrl/pinctrl.h>
21 #include <linux/pinctrl/pinconf.h>
22 #include <linux/pinctrl/pinconf-generic.h>
23 #include "core.h"
24 #include "pinconf.h"
25 
26 #ifdef CONFIG_DEBUG_FS
27 
28 struct pin_config_item {
29 	const enum pin_config_param param;
30 	const char * const display;
31 	const char * const format;
32 };
33 
34 #define PCONFDUMP(a, b, c) { .param = a, .display = b, .format = c }
35 
36 struct pin_config_item conf_items[] = {
37 	PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL),
38 	PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL),
39 	PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL),
40 	PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL),
41 	PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL),
42 	PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL),
43 	PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL),
44 	PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL),
45 	PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL),
46 	PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "time units"),
47 	PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector"),
48 	PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL),
49 	PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode"),
50 	PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level"),
51 };
52 
53 void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
54 			      struct seq_file *s, unsigned pin)
55 {
56 	const struct pinconf_ops *ops = pctldev->desc->confops;
57 	int i;
58 
59 	if (!ops->is_generic)
60 		return;
61 
62 	for(i = 0; i < ARRAY_SIZE(conf_items); i++) {
63 		unsigned long config;
64 		int ret;
65 
66 		/* We want to check out this parameter */
67 		config = pinconf_to_config_packed(conf_items[i].param, 0);
68 		ret = pin_config_get_for_pin(pctldev, pin, &config);
69 		/* These are legal errors */
70 		if (ret == -EINVAL || ret == -ENOTSUPP)
71 			continue;
72 		if (ret) {
73 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
74 			continue;
75 		}
76 		/* Space between multiple configs */
77 		seq_puts(s, " ");
78 		seq_puts(s, conf_items[i].display);
79 		/* Print unit if available */
80 		if (conf_items[i].format &&
81 		    pinconf_to_config_argument(config) != 0)
82 			seq_printf(s, " (%u %s)",
83 				   pinconf_to_config_argument(config),
84 				   conf_items[i].format);
85 	}
86 }
87 
88 void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
89 			      struct seq_file *s, const char *gname)
90 {
91 	const struct pinconf_ops *ops = pctldev->desc->confops;
92 	int i;
93 
94 	if (!ops->is_generic)
95 		return;
96 
97 	for(i = 0; i < ARRAY_SIZE(conf_items); i++) {
98 		unsigned long config;
99 		int ret;
100 
101 		/* We want to check out this parameter */
102 		config = pinconf_to_config_packed(conf_items[i].param, 0);
103 		ret = pin_config_group_get(dev_name(pctldev->dev), gname,
104 					   &config);
105 		/* These are legal errors */
106 		if (ret == -EINVAL || ret == -ENOTSUPP)
107 			continue;
108 		if (ret) {
109 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
110 			continue;
111 		}
112 		/* Space between multiple configs */
113 		seq_puts(s, " ");
114 		seq_puts(s, conf_items[i].display);
115 		/* Print unit if available */
116 		if (conf_items[i].format && config != 0)
117 			seq_printf(s, " (%u %s)",
118 				   pinconf_to_config_argument(config),
119 				   conf_items[i].format);
120 	}
121 }
122 
123 #endif
124