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/module.h>
16 #include <linux/init.h>
17 #include <linux/device.h>
18 #include <linux/slab.h>
19 #include <linux/debugfs.h>
20 #include <linux/seq_file.h>
21 #include <linux/pinctrl/pinctrl.h>
22 #include <linux/pinctrl/pinconf.h>
23 #include <linux/pinctrl/pinconf-generic.h>
24 #include "core.h"
25 #include "pinconf.h"
26 
27 #ifdef CONFIG_DEBUG_FS
28 
29 struct pin_config_item {
30 	const enum pin_config_param param;
31 	const char * const display;
32 	const char * const format;
33 };
34 
35 #define PCONFDUMP(a, b, c) { .param = a, .display = b, .format = c }
36 
37 static struct pin_config_item conf_items[] = {
38 	PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL),
39 	PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL),
40 	PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL),
41 	PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL),
42 	PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL),
43 	PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL),
44 	PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL),
45 	PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL),
46 	PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL),
47 	PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "time units"),
48 	PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector"),
49 	PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL),
50 	PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode"),
51 	PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level"),
52 };
53 
54 void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
55 			      struct seq_file *s, unsigned pin)
56 {
57 	const struct pinconf_ops *ops = pctldev->desc->confops;
58 	int i;
59 
60 	if (!ops->is_generic)
61 		return;
62 
63 	for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
64 		unsigned long config;
65 		int ret;
66 
67 		/* We want to check out this parameter */
68 		config = pinconf_to_config_packed(conf_items[i].param, 0);
69 		ret = pin_config_get_for_pin(pctldev, pin, &config);
70 		/* These are legal errors */
71 		if (ret == -EINVAL || ret == -ENOTSUPP)
72 			continue;
73 		if (ret) {
74 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
75 			continue;
76 		}
77 		/* Space between multiple configs */
78 		seq_puts(s, " ");
79 		seq_puts(s, conf_items[i].display);
80 		/* Print unit if available */
81 		if (conf_items[i].format &&
82 		    pinconf_to_config_argument(config) != 0)
83 			seq_printf(s, " (%u %s)",
84 				   pinconf_to_config_argument(config),
85 				   conf_items[i].format);
86 	}
87 }
88 
89 void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
90 			      struct seq_file *s, const char *gname)
91 {
92 	const struct pinconf_ops *ops = pctldev->desc->confops;
93 	int i;
94 
95 	if (!ops->is_generic)
96 		return;
97 
98 	for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
99 		unsigned long config;
100 		int ret;
101 
102 		/* We want to check out this parameter */
103 		config = pinconf_to_config_packed(conf_items[i].param, 0);
104 		ret = pin_config_group_get(dev_name(pctldev->dev), gname,
105 					   &config);
106 		/* These are legal errors */
107 		if (ret == -EINVAL || ret == -ENOTSUPP)
108 			continue;
109 		if (ret) {
110 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
111 			continue;
112 		}
113 		/* Space between multiple configs */
114 		seq_puts(s, " ");
115 		seq_puts(s, conf_items[i].display);
116 		/* Print unit if available */
117 		if (conf_items[i].format && config != 0)
118 			seq_printf(s, " (%u %s)",
119 				   pinconf_to_config_argument(config),
120 				   conf_items[i].format);
121 	}
122 }
123 
124 void pinconf_generic_dump_config(struct pinctrl_dev *pctldev,
125 				 struct seq_file *s, unsigned long config)
126 {
127 	int i;
128 
129 	for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
130 		if (pinconf_to_config_param(config) != conf_items[i].param)
131 			continue;
132 		seq_printf(s, "%s: 0x%x", conf_items[i].display,
133 			   pinconf_to_config_argument(config));
134 	}
135 }
136 EXPORT_SYMBOL_GPL(pinconf_generic_dump_config);
137 #endif
138