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_DISABLE, "input schmitt disabled", 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_LOW_POWER_MODE, "pin low power", "mode"),
49 };
50 
51 void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
52 			      struct seq_file *s, unsigned pin)
53 {
54 	const struct pinconf_ops *ops = pctldev->desc->confops;
55 	int i;
56 
57 	if (!ops->is_generic)
58 		return;
59 
60 	for(i = 0; i < ARRAY_SIZE(conf_items); i++) {
61 		unsigned long config;
62 		int ret;
63 
64 		/* We want to check out this parameter */
65 		config = pinconf_to_config_packed(conf_items[i].param, 0);
66 		ret = pin_config_get_for_pin(pctldev, pin, &config);
67 		/* These are legal errors */
68 		if (ret == -EINVAL || ret == -ENOTSUPP)
69 			continue;
70 		if (ret) {
71 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
72 			continue;
73 		}
74 		/* Space between multiple configs */
75 		seq_puts(s, " ");
76 		seq_puts(s, conf_items[i].display);
77 		/* Print unit if available */
78 		if (conf_items[i].format &&
79 		    pinconf_to_config_argument(config) != 0)
80 			seq_printf(s, " (%u %s)",
81 				   pinconf_to_config_argument(config),
82 				   conf_items[i].format);
83 	}
84 }
85 
86 void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
87 			      struct seq_file *s, const char *gname)
88 {
89 	const struct pinconf_ops *ops = pctldev->desc->confops;
90 	int i;
91 
92 	if (!ops->is_generic)
93 		return;
94 
95 	for(i = 0; i < ARRAY_SIZE(conf_items); i++) {
96 		unsigned long config;
97 		int ret;
98 
99 		/* We want to check out this parameter */
100 		config = pinconf_to_config_packed(conf_items[i].param, 0);
101 		ret = pin_config_group_get(dev_name(pctldev->dev), gname,
102 					   &config);
103 		/* These are legal errors */
104 		if (ret == -EINVAL || ret == -ENOTSUPP)
105 			continue;
106 		if (ret) {
107 			seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
108 			continue;
109 		}
110 		/* Space between multiple configs */
111 		seq_puts(s, " ");
112 		seq_puts(s, conf_items[i].display);
113 		/* Print unit if available */
114 		if (conf_items[i].format && config != 0)
115 			seq_printf(s, " (%u %s)",
116 				   pinconf_to_config_argument(config),
117 				   conf_items[i].format);
118 	}
119 }
120 
121 #endif
122