1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2015 Verifone Int.
4  *
5  * Author: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
6  *
7  * This driver is based on the gpio-tps65912 implementation.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/errno.h>
13 #include <linux/gpio/driver.h>
14 #include <linux/platform_device.h>
15 #include <linux/regmap.h>
16 #include <linux/mfd/tps65218.h>
17 
18 struct tps65218_gpio {
19 	struct tps65218 *tps65218;
20 	struct gpio_chip gpio_chip;
21 };
22 
tps65218_gpio_get(struct gpio_chip * gc,unsigned offset)23 static int tps65218_gpio_get(struct gpio_chip *gc, unsigned offset)
24 {
25 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
26 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
27 	unsigned int val;
28 	int ret;
29 
30 	ret = regmap_read(tps65218->regmap, TPS65218_REG_ENABLE2, &val);
31 	if (ret)
32 		return ret;
33 
34 	return !!(val & (TPS65218_ENABLE2_GPIO1 << offset));
35 }
36 
tps65218_gpio_set(struct gpio_chip * gc,unsigned offset,int value)37 static void tps65218_gpio_set(struct gpio_chip *gc, unsigned offset,
38 			      int value)
39 {
40 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
41 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
42 
43 	if (value)
44 		tps65218_set_bits(tps65218, TPS65218_REG_ENABLE2,
45 				  TPS65218_ENABLE2_GPIO1 << offset,
46 				  TPS65218_ENABLE2_GPIO1 << offset,
47 				  TPS65218_PROTECT_L1);
48 	else
49 		tps65218_clear_bits(tps65218, TPS65218_REG_ENABLE2,
50 				    TPS65218_ENABLE2_GPIO1 << offset,
51 				    TPS65218_PROTECT_L1);
52 }
53 
tps65218_gpio_output(struct gpio_chip * gc,unsigned offset,int value)54 static int tps65218_gpio_output(struct gpio_chip *gc, unsigned offset,
55 				int value)
56 {
57 	/* Only drives GPOs */
58 	tps65218_gpio_set(gc, offset, value);
59 	return 0;
60 }
61 
tps65218_gpio_input(struct gpio_chip * gc,unsigned offset)62 static int tps65218_gpio_input(struct gpio_chip *gc, unsigned offset)
63 {
64 	return -EPERM;
65 }
66 
tps65218_gpio_request(struct gpio_chip * gc,unsigned offset)67 static int tps65218_gpio_request(struct gpio_chip *gc, unsigned offset)
68 {
69 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
70 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
71 	int ret;
72 
73 	if (gpiochip_line_is_open_source(gc, offset)) {
74 		dev_err(gc->parent, "can't work as open source\n");
75 		return -EINVAL;
76 	}
77 
78 	switch (offset) {
79 	case 0:
80 		if (!gpiochip_line_is_open_drain(gc, offset)) {
81 			dev_err(gc->parent, "GPO1 works only as open drain\n");
82 			return -EINVAL;
83 		}
84 
85 		/* Disable sequencer for GPO1 */
86 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
87 					  TPS65218_SEQ7_GPO1_SEQ_MASK,
88 					  TPS65218_PROTECT_L1);
89 		if (ret)
90 			return ret;
91 
92 		/* Setup GPO1 */
93 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
94 					  TPS65218_CONFIG1_IO1_SEL,
95 					  TPS65218_PROTECT_L1);
96 		if (ret)
97 			return ret;
98 
99 		break;
100 	case 1:
101 		/* Setup GPO2 */
102 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG1,
103 					  TPS65218_CONFIG1_IO1_SEL,
104 					  TPS65218_PROTECT_L1);
105 		if (ret)
106 			return ret;
107 
108 		break;
109 
110 	case 2:
111 		if (!gpiochip_line_is_open_drain(gc, offset)) {
112 			dev_err(gc->parent, "GPO3 works only as open drain\n");
113 			return -EINVAL;
114 		}
115 
116 		/* Disable sequencer for GPO3 */
117 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_SEQ7,
118 					  TPS65218_SEQ7_GPO3_SEQ_MASK,
119 					  TPS65218_PROTECT_L1);
120 		if (ret)
121 			return ret;
122 
123 		/* Setup GPO3 */
124 		ret = tps65218_clear_bits(tps65218, TPS65218_REG_CONFIG2,
125 					  TPS65218_CONFIG2_DC12_RST,
126 					  TPS65218_PROTECT_L1);
127 		if (ret)
128 			return ret;
129 
130 		break;
131 	default:
132 		return -EINVAL;
133 	}
134 
135 	return 0;
136 }
137 
tps65218_gpio_set_config(struct gpio_chip * gc,unsigned offset,unsigned long config)138 static int tps65218_gpio_set_config(struct gpio_chip *gc, unsigned offset,
139 				    unsigned long config)
140 {
141 	struct tps65218_gpio *tps65218_gpio = gpiochip_get_data(gc);
142 	struct tps65218 *tps65218 = tps65218_gpio->tps65218;
143 	enum pin_config_param param = pinconf_to_config_param(config);
144 
145 	switch (offset) {
146 	case 0:
147 	case 2:
148 		/* GPO1 is hardwired to be open drain */
149 		if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN)
150 			return 0;
151 		return -ENOTSUPP;
152 	case 1:
153 		/* GPO2 is push-pull by default, can be set as open drain. */
154 		if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN)
155 			return tps65218_clear_bits(tps65218,
156 						   TPS65218_REG_CONFIG1,
157 						   TPS65218_CONFIG1_GPO2_BUF,
158 						   TPS65218_PROTECT_L1);
159 		if (param == PIN_CONFIG_DRIVE_PUSH_PULL)
160 			return tps65218_set_bits(tps65218,
161 						 TPS65218_REG_CONFIG1,
162 						 TPS65218_CONFIG1_GPO2_BUF,
163 						 TPS65218_CONFIG1_GPO2_BUF,
164 						 TPS65218_PROTECT_L1);
165 		return -ENOTSUPP;
166 	default:
167 		break;
168 	}
169 	return -ENOTSUPP;
170 }
171 
172 static const struct gpio_chip template_chip = {
173 	.label			= "gpio-tps65218",
174 	.owner			= THIS_MODULE,
175 	.request		= tps65218_gpio_request,
176 	.direction_output	= tps65218_gpio_output,
177 	.direction_input	= tps65218_gpio_input,
178 	.get			= tps65218_gpio_get,
179 	.set			= tps65218_gpio_set,
180 	.set_config		= tps65218_gpio_set_config,
181 	.can_sleep		= true,
182 	.ngpio			= 3,
183 	.base			= -1,
184 };
185 
tps65218_gpio_probe(struct platform_device * pdev)186 static int tps65218_gpio_probe(struct platform_device *pdev)
187 {
188 	struct tps65218 *tps65218 = dev_get_drvdata(pdev->dev.parent);
189 	struct tps65218_gpio *tps65218_gpio;
190 
191 	tps65218_gpio = devm_kzalloc(&pdev->dev, sizeof(*tps65218_gpio),
192 				     GFP_KERNEL);
193 	if (!tps65218_gpio)
194 		return -ENOMEM;
195 
196 	tps65218_gpio->tps65218 = tps65218;
197 	tps65218_gpio->gpio_chip = template_chip;
198 	tps65218_gpio->gpio_chip.parent = &pdev->dev;
199 #ifdef CONFIG_OF_GPIO
200 	tps65218_gpio->gpio_chip.of_node = pdev->dev.of_node;
201 #endif
202 
203 	return devm_gpiochip_add_data(&pdev->dev, &tps65218_gpio->gpio_chip,
204 				      tps65218_gpio);
205 }
206 
207 static const struct of_device_id tps65218_dt_match[] = {
208 	{ .compatible = "ti,tps65218-gpio" },
209 	{  }
210 };
211 MODULE_DEVICE_TABLE(of, tps65218_dt_match);
212 
213 static const struct platform_device_id tps65218_gpio_id_table[] = {
214 	{ "tps65218-gpio", },
215 	{ /* sentinel */ }
216 };
217 MODULE_DEVICE_TABLE(platform, tps65218_gpio_id_table);
218 
219 static struct platform_driver tps65218_gpio_driver = {
220 	.driver = {
221 		.name = "tps65218-gpio",
222 		.of_match_table = of_match_ptr(tps65218_dt_match)
223 	},
224 	.probe = tps65218_gpio_probe,
225 	.id_table = tps65218_gpio_id_table,
226 };
227 
228 module_platform_driver(tps65218_gpio_driver);
229 
230 MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
231 MODULE_DESCRIPTION("GPO interface for TPS65218 PMICs");
232 MODULE_LICENSE("GPL v2");
233