1 /*
2  * Copyright 2015 Verifone Int.
3  *
4  * Author: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify i t
7  * under  the terms of the GNU General  Public License as published by th e
8  * Free Software Foundation;  either version 2 of the License, or (at you r
9  * option) any later version.
10  *
11  * This driver is based on the gpio-tps65912 implementation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/errno.h>
17 #include <linux/gpio/driver.h>
18 #include <linux/platform_device.h>
19 #include <linux/regmap.h>
20 #include <linux/mfd/tps65218.h>
21 
22 struct tps65218_gpio {
23 	struct tps65218 *tps65218;
24 	struct gpio_chip gpio_chip;
25 };
26 
tps65218_gpio_get(struct gpio_chip * gc,unsigned offset)27 static int tps65218_gpio_get(struct gpio_chip *gc, unsigned offset)
28 {
29 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
30 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
31 	unsigned int val;
32 	int ret;
33 
34 	ret = regmap_read(tps65218->regmap, TPS65218_REG_ENABLE2, &val);
35 	if (ret)
36 		return ret;
37 
38 	return !!(val & (TPS65218_ENABLE2_GPIO1 << offset));
39 }
40 
tps65218_gpio_set(struct gpio_chip * gc,unsigned offset,int value)41 static void tps65218_gpio_set(struct gpio_chip *gc, unsigned offset,
42 			      int value)
43 {
44 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
45 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
46 
47 	if (value)
48 		tps65218_set_bits(tps65218, TPS65218_REG_ENABLE2,
49 				  TPS65218_ENABLE2_GPIO1 << offset,
50 				  TPS65218_ENABLE2_GPIO1 << offset,
51 				  TPS65218_PROTECT_L1);
52 	else
53 		tps65218_clear_bits(tps65218, TPS65218_REG_ENABLE2,
54 				    TPS65218_ENABLE2_GPIO1 << offset,
55 				    TPS65218_PROTECT_L1);
56 }
57 
tps65218_gpio_output(struct gpio_chip * gc,unsigned offset,int value)58 static int tps65218_gpio_output(struct gpio_chip *gc, unsigned offset,
59 				int value)
60 {
61 	/* Only drives GPOs */
62 	tps65218_gpio_set(gc, offset, value);
63 	return 0;
64 }
65 
tps65218_gpio_input(struct gpio_chip * gc,unsigned offset)66 static int tps65218_gpio_input(struct gpio_chip *gc, unsigned offset)
67 {
68 	return -EPERM;
69 }
70 
tps65218_gpio_request(struct gpio_chip * gc,unsigned offset)71 static int tps65218_gpio_request(struct gpio_chip *gc, unsigned offset)
72 {
73 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
74 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
75 	int ret;
76 
77 	if (gpiochip_line_is_open_source(gc, offset)) {
78 		dev_err(gc->parent, "can't work as open source\n");
79 		return -EINVAL;
80 	}
81 
82 	switch (offset) {
83 	case 0:
84 		if (!gpiochip_line_is_open_drain(gc, offset)) {
85 			dev_err(gc->parent, "GPO1 works only as open drain\n");
86 			return -EINVAL;
87 		}
88 
89 		/* Disable sequencer for GPO1 */
90 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
91 					  TPS65218_SEQ7_GPO1_SEQ_MASK,
92 					  TPS65218_PROTECT_L1);
93 		if (ret)
94 			return ret;
95 
96 		/* Setup GPO1 */
97 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
98 					  TPS65218_CONFIG1_IO1_SEL,
99 					  TPS65218_PROTECT_L1);
100 		if (ret)
101 			return ret;
102 
103 		break;
104 	case 1:
105 		/* Setup GPO2 */
106 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
107 					  TPS65218_CONFIG1_IO1_SEL,
108 					  TPS65218_PROTECT_L1);
109 		if (ret)
110 			return ret;
111 
112 		break;
113 
114 	case 2:
115 		if (!gpiochip_line_is_open_drain(gc, offset)) {
116 			dev_err(gc->parent, "GPO3 works only as open drain\n");
117 			return -EINVAL;
118 		}
119 
120 		/* Disable sequencer for GPO3 */
121 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
122 					  TPS65218_SEQ7_GPO3_SEQ_MASK,
123 					  TPS65218_PROTECT_L1);
124 		if (ret)
125 			return ret;
126 
127 		/* Setup GPO3 */
128 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG2,
129 					  TPS65218_CONFIG2_DC12_RST,
130 					  TPS65218_PROTECT_L1);
131 		if (ret)
132 			return ret;
133 
134 		break;
135 	default:
136 		return -EINVAL;
137 	}
138 
139 	return 0;
140 }
141 
tps65218_gpio_set_config(struct gpio_chip * gc,unsigned offset,unsigned long config)142 static int tps65218_gpio_set_config(struct gpio_chip *gc, unsigned offset,
143 				    unsigned long config)
144 {
145 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
146 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
147 	enum pin_config_param param = pinconf_to_config_param(config);
148 
149 	switch (offset) {
150 	case 0:
151 	case 2:
152 		/* GPO1 is hardwired to be open drain */
153 		if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN)
154 			return 0;
155 		return -ENOTSUPP;
156 	case 1:
157 		/* GPO2 is push-pull by default, can be set as open drain. */
158 		if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN)
159 			return tps65218_clear_bits(tps65218,
160 						   TPS65218_REG_CONFIG1,
161 						   TPS65218_CONFIG1_GPO2_BUF,
162 						   TPS65218_PROTECT_L1);
163 		if (param == PIN_CONFIG_DRIVE_PUSH_PULL)
164 			return tps65218_set_bits(tps65218,
165 						 TPS65218_REG_CONFIG1,
166 						 TPS65218_CONFIG1_GPO2_BUF,
167 						 TPS65218_CONFIG1_GPO2_BUF,
168 						 TPS65218_PROTECT_L1);
169 		return -ENOTSUPP;
170 	default:
171 		break;
172 	}
173 	return -ENOTSUPP;
174 }
175 
176 static const struct gpio_chip template_chip = {
177 	.label			= "gpio-tps65218",
178 	.owner			= THIS_MODULE,
179 	.request		= tps65218_gpio_request,
180 	.direction_output	= tps65218_gpio_output,
181 	.direction_input	= tps65218_gpio_input,
182 	.get			= tps65218_gpio_get,
183 	.set			= tps65218_gpio_set,
184 	.set_config		= tps65218_gpio_set_config,
185 	.can_sleep		= true,
186 	.ngpio			= 3,
187 	.base			= -1,
188 };
189 
tps65218_gpio_probe(struct platform_device * pdev)190 static int tps65218_gpio_probe(struct platform_device *pdev)
191 {
192 	struct tps65218 *tps65218 = dev_get_drvdata(pdev->dev.parent);
193 	struct tps65218_gpio *tps65218_gpio;
194 	int ret;
195 
196 	tps65218_gpio = devm_kzalloc(&pdev->dev, sizeof(*tps65218_gpio),
197 				     GFP_KERNEL);
198 	if (!tps65218_gpio)
199 		return -ENOMEM;
200 
201 	tps65218_gpio->tps65218 = tps65218;
202 	tps65218_gpio->gpio_chip = template_chip;
203 	tps65218_gpio->gpio_chip.parent = &pdev->dev;
204 #ifdef CONFIG_OF_GPIO
205 	tps65218_gpio->gpio_chip.of_node = pdev->dev.of_node;
206 #endif
207 
208 	ret = devm_gpiochip_add_data(&pdev->dev, &tps65218_gpio->gpio_chip,
209 				     tps65218_gpio);
210 	if (ret < 0) {
211 		dev_err(&pdev->dev, "Failed to register gpiochip, %d\n", ret);
212 		return ret;
213 	}
214 
215 	platform_set_drvdata(pdev, tps65218_gpio);
216 
217 	return ret;
218 }
219 
220 static const struct of_device_id tps65218_dt_match[] = {
221 	{ .compatible = "ti,tps65218-gpio" },
222 	{  }
223 };
224 MODULE_DEVICE_TABLE(of, tps65218_dt_match);
225 
226 static const struct platform_device_id tps65218_gpio_id_table[] = {
227 	{ "tps65218-gpio", },
228 	{ /* sentinel */ }
229 };
230 MODULE_DEVICE_TABLE(platform, tps65218_gpio_id_table);
231 
232 static struct platform_driver tps65218_gpio_driver = {
233 	.driver = {
234 		.name = "tps65218-gpio",
235 		.of_match_table = of_match_ptr(tps65218_dt_match)
236 	},
237 	.probe = tps65218_gpio_probe,
238 	.id_table = tps65218_gpio_id_table,
239 };
240 
241 module_platform_driver(tps65218_gpio_driver);
242 
243 MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
244 MODULE_DESCRIPTION("GPO interface for TPS65218 PMICs");
245 MODULE_LICENSE("GPL v2");
246 MODULE_ALIAS("platform:tps65218-gpio");
247