xref: /openbmc/linux/drivers/gpio/gpio-tps68470.c (revision cfbb9be8)
1 /*
2  * GPIO driver for TPS68470 PMIC
3  *
4  * Copyright (C) 2017 Intel Corporation
5  *
6  * Authors:
7  *	Antti Laakso <antti.laakso@intel.com>
8  *	Tianshu Qiu <tian.shu.qiu@intel.com>
9  *	Jian Xu Zheng <jian.xu.zheng@intel.com>
10  *	Yuning Pu <yuning.pu@intel.com>
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation version 2.
15  *
16  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
17  * kind, whether express or implied; without even the implied warranty
18  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  */
21 
22 #include <linux/gpio/driver.h>
23 #include <linux/mfd/tps68470.h>
24 #include <linux/module.h>
25 #include <linux/platform_device.h>
26 #include <linux/regmap.h>
27 
28 #define TPS68470_N_LOGIC_OUTPUT	3
29 #define TPS68470_N_REGULAR_GPIO	7
30 #define TPS68470_N_GPIO	(TPS68470_N_LOGIC_OUTPUT + TPS68470_N_REGULAR_GPIO)
31 
32 struct tps68470_gpio_data {
33 	struct regmap *tps68470_regmap;
34 	struct gpio_chip gc;
35 };
36 
37 static int tps68470_gpio_get(struct gpio_chip *gc, unsigned int offset)
38 {
39 	struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
40 	struct regmap *regmap = tps68470_gpio->tps68470_regmap;
41 	unsigned int reg = TPS68470_REG_GPDO;
42 	int val, ret;
43 
44 	if (offset >= TPS68470_N_REGULAR_GPIO) {
45 		offset -= TPS68470_N_REGULAR_GPIO;
46 		reg = TPS68470_REG_SGPO;
47 	}
48 
49 	ret = regmap_read(regmap, reg, &val);
50 	if (ret) {
51 		dev_err(tps68470_gpio->gc.parent, "reg 0x%x read failed\n",
52 			TPS68470_REG_SGPO);
53 		return ret;
54 	}
55 	return !!(val & BIT(offset));
56 }
57 
58 /* Return 0 if output, 1 if input */
59 static int tps68470_gpio_get_direction(struct gpio_chip *gc,
60 				       unsigned int offset)
61 {
62 	struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
63 	struct regmap *regmap = tps68470_gpio->tps68470_regmap;
64 	int val, ret;
65 
66 	/* rest are always outputs */
67 	if (offset >= TPS68470_N_REGULAR_GPIO)
68 		return 0;
69 
70 	ret = regmap_read(regmap, TPS68470_GPIO_CTL_REG_A(offset), &val);
71 	if (ret) {
72 		dev_err(tps68470_gpio->gc.parent, "reg 0x%x read failed\n",
73 			TPS68470_GPIO_CTL_REG_A(offset));
74 		return ret;
75 	}
76 
77 	val &= TPS68470_GPIO_MODE_MASK;
78 	return val >= TPS68470_GPIO_MODE_OUT_CMOS ? 0 : 1;
79 }
80 
81 static void tps68470_gpio_set(struct gpio_chip *gc, unsigned int offset,
82 				int value)
83 {
84 	struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
85 	struct regmap *regmap = tps68470_gpio->tps68470_regmap;
86 	unsigned int reg = TPS68470_REG_GPDO;
87 
88 	if (offset >= TPS68470_N_REGULAR_GPIO) {
89 		reg = TPS68470_REG_SGPO;
90 		offset -= TPS68470_N_REGULAR_GPIO;
91 	}
92 
93 	regmap_update_bits(regmap, reg, BIT(offset), value ? BIT(offset) : 0);
94 }
95 
96 static int tps68470_gpio_output(struct gpio_chip *gc, unsigned int offset,
97 				int value)
98 {
99 	struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
100 	struct regmap *regmap = tps68470_gpio->tps68470_regmap;
101 
102 	/* rest are always outputs */
103 	if (offset >= TPS68470_N_REGULAR_GPIO)
104 		return 0;
105 
106 	/* Set the initial value */
107 	tps68470_gpio_set(gc, offset, value);
108 
109 	return regmap_update_bits(regmap, TPS68470_GPIO_CTL_REG_A(offset),
110 				 TPS68470_GPIO_MODE_MASK,
111 				 TPS68470_GPIO_MODE_OUT_CMOS);
112 }
113 
114 static int tps68470_gpio_input(struct gpio_chip *gc, unsigned int offset)
115 {
116 	struct tps68470_gpio_data *tps68470_gpio = gpiochip_get_data(gc);
117 	struct regmap *regmap = tps68470_gpio->tps68470_regmap;
118 
119 	/* rest are always outputs */
120 	if (offset >= TPS68470_N_REGULAR_GPIO)
121 		return -EINVAL;
122 
123 	return regmap_update_bits(regmap, TPS68470_GPIO_CTL_REG_A(offset),
124 				   TPS68470_GPIO_MODE_MASK, 0x00);
125 }
126 
127 static const char *tps68470_names[TPS68470_N_GPIO] = {
128 	"gpio.0", "gpio.1", "gpio.2", "gpio.3",
129 	"gpio.4", "gpio.5", "gpio.6",
130 	"s_enable", "s_idle", "s_resetn",
131 };
132 
133 static int tps68470_gpio_probe(struct platform_device *pdev)
134 {
135 	struct tps68470_gpio_data *tps68470_gpio;
136 	int ret;
137 
138 	tps68470_gpio = devm_kzalloc(&pdev->dev, sizeof(*tps68470_gpio),
139 				     GFP_KERNEL);
140 	if (!tps68470_gpio)
141 		return -ENOMEM;
142 
143 	tps68470_gpio->tps68470_regmap = dev_get_drvdata(pdev->dev.parent);
144 	tps68470_gpio->gc.label = "tps68470-gpio";
145 	tps68470_gpio->gc.owner = THIS_MODULE;
146 	tps68470_gpio->gc.direction_input = tps68470_gpio_input;
147 	tps68470_gpio->gc.direction_output = tps68470_gpio_output;
148 	tps68470_gpio->gc.get = tps68470_gpio_get;
149 	tps68470_gpio->gc.get_direction = tps68470_gpio_get_direction;
150 	tps68470_gpio->gc.set = tps68470_gpio_set;
151 	tps68470_gpio->gc.can_sleep = true;
152 	tps68470_gpio->gc.names = tps68470_names;
153 	tps68470_gpio->gc.ngpio = TPS68470_N_GPIO;
154 	tps68470_gpio->gc.base = -1;
155 	tps68470_gpio->gc.parent = &pdev->dev;
156 
157 	ret = devm_gpiochip_add_data(&pdev->dev, &tps68470_gpio->gc,
158 				     tps68470_gpio);
159 	if (ret < 0) {
160 		dev_err(&pdev->dev, "Failed to register gpio_chip: %d\n", ret);
161 		return ret;
162 	}
163 
164 	platform_set_drvdata(pdev, tps68470_gpio);
165 
166 	return ret;
167 }
168 
169 static struct platform_driver tps68470_gpio_driver = {
170 	.driver = {
171 		   .name = "tps68470-gpio",
172 	},
173 	.probe = tps68470_gpio_probe,
174 };
175 
176 builtin_platform_driver(tps68470_gpio_driver)
177