1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com/
4 * Keerthy <j-keerthy@ti.com>
5 *
6 * Based on the TPS65218 driver
7 */
8
9 #include <linux/gpio/driver.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/regmap.h>
13
14 #include <linux/mfd/lp873x.h>
15
16 #define BITS_PER_GPO 0x4
17 #define LP873X_GPO_CTRL_OD 0x2
18
19 struct lp873x_gpio {
20 struct gpio_chip chip;
21 struct lp873x *lp873;
22 };
23
lp873x_gpio_get_direction(struct gpio_chip * chip,unsigned int offset)24 static int lp873x_gpio_get_direction(struct gpio_chip *chip,
25 unsigned int offset)
26 {
27 /* This device is output only */
28 return GPIO_LINE_DIRECTION_OUT;
29 }
30
lp873x_gpio_direction_input(struct gpio_chip * chip,unsigned int offset)31 static int lp873x_gpio_direction_input(struct gpio_chip *chip,
32 unsigned int offset)
33 {
34 /* This device is output only */
35 return -EINVAL;
36 }
37
lp873x_gpio_direction_output(struct gpio_chip * chip,unsigned int offset,int value)38 static int lp873x_gpio_direction_output(struct gpio_chip *chip,
39 unsigned int offset, int value)
40 {
41 struct lp873x_gpio *gpio = gpiochip_get_data(chip);
42
43 /* Set the initial value */
44 return regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
45 BIT(offset * BITS_PER_GPO),
46 value ? BIT(offset * BITS_PER_GPO) : 0);
47 }
48
lp873x_gpio_get(struct gpio_chip * chip,unsigned int offset)49 static int lp873x_gpio_get(struct gpio_chip *chip, unsigned int offset)
50 {
51 struct lp873x_gpio *gpio = gpiochip_get_data(chip);
52 int ret, val;
53
54 ret = regmap_read(gpio->lp873->regmap, LP873X_REG_GPO_CTRL, &val);
55 if (ret < 0)
56 return ret;
57
58 return val & BIT(offset * BITS_PER_GPO);
59 }
60
lp873x_gpio_set(struct gpio_chip * chip,unsigned int offset,int value)61 static void lp873x_gpio_set(struct gpio_chip *chip, unsigned int offset,
62 int value)
63 {
64 struct lp873x_gpio *gpio = gpiochip_get_data(chip);
65
66 regmap_update_bits(gpio->lp873->regmap, LP873X_REG_GPO_CTRL,
67 BIT(offset * BITS_PER_GPO),
68 value ? BIT(offset * BITS_PER_GPO) : 0);
69 }
70
lp873x_gpio_request(struct gpio_chip * gc,unsigned int offset)71 static int lp873x_gpio_request(struct gpio_chip *gc, unsigned int offset)
72 {
73 struct lp873x_gpio *gpio = gpiochip_get_data(gc);
74 int ret;
75
76 switch (offset) {
77 case 0:
78 /* No MUX Set up Needed for GPO */
79 break;
80 case 1:
81 /* Setup the CLKIN_PIN_SEL MUX to GPO2 */
82 ret = regmap_update_bits(gpio->lp873->regmap, LP873X_REG_CONFIG,
83 LP873X_CONFIG_CLKIN_PIN_SEL, 0);
84 if (ret)
85 return ret;
86
87 break;
88 default:
89 return -EINVAL;
90 }
91
92 return 0;
93 }
94
lp873x_gpio_set_config(struct gpio_chip * gc,unsigned offset,unsigned long config)95 static int lp873x_gpio_set_config(struct gpio_chip *gc, unsigned offset,
96 unsigned long config)
97 {
98 struct lp873x_gpio *gpio = gpiochip_get_data(gc);
99
100 switch (pinconf_to_config_param(config)) {
101 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
102 return regmap_update_bits(gpio->lp873->regmap,
103 LP873X_REG_GPO_CTRL,
104 BIT(offset * BITS_PER_GPO +
105 LP873X_GPO_CTRL_OD),
106 BIT(offset * BITS_PER_GPO +
107 LP873X_GPO_CTRL_OD));
108
109 case PIN_CONFIG_DRIVE_PUSH_PULL:
110 return regmap_update_bits(gpio->lp873->regmap,
111 LP873X_REG_GPO_CTRL,
112 BIT(offset * BITS_PER_GPO +
113 LP873X_GPO_CTRL_OD), 0);
114 default:
115 return -ENOTSUPP;
116 }
117 }
118
119 static const struct gpio_chip template_chip = {
120 .label = "lp873x-gpio",
121 .owner = THIS_MODULE,
122 .request = lp873x_gpio_request,
123 .get_direction = lp873x_gpio_get_direction,
124 .direction_input = lp873x_gpio_direction_input,
125 .direction_output = lp873x_gpio_direction_output,
126 .get = lp873x_gpio_get,
127 .set = lp873x_gpio_set,
128 .set_config = lp873x_gpio_set_config,
129 .base = -1,
130 .ngpio = 2,
131 .can_sleep = true,
132 };
133
lp873x_gpio_probe(struct platform_device * pdev)134 static int lp873x_gpio_probe(struct platform_device *pdev)
135 {
136 struct lp873x_gpio *gpio;
137 int ret;
138
139 gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
140 if (!gpio)
141 return -ENOMEM;
142
143 platform_set_drvdata(pdev, gpio);
144
145 gpio->lp873 = dev_get_drvdata(pdev->dev.parent);
146 gpio->chip = template_chip;
147 gpio->chip.parent = gpio->lp873->dev;
148
149 ret = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
150 if (ret < 0) {
151 dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
152 return ret;
153 }
154
155 return 0;
156 }
157
158 static const struct platform_device_id lp873x_gpio_id_table[] = {
159 { "lp873x-gpio", },
160 { /* sentinel */ }
161 };
162 MODULE_DEVICE_TABLE(platform, lp873x_gpio_id_table);
163
164 static struct platform_driver lp873x_gpio_driver = {
165 .driver = {
166 .name = "lp873x-gpio",
167 },
168 .probe = lp873x_gpio_probe,
169 .id_table = lp873x_gpio_id_table,
170 };
171 module_platform_driver(lp873x_gpio_driver);
172
173 MODULE_AUTHOR("Keerthy <j-keerthy@ti.com>");
174 MODULE_DESCRIPTION("LP873X GPIO driver");
175 MODULE_LICENSE("GPL v2");
176