1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Analog Devices ADP5585 GPIO driver
4  *
5  * Copyright 2022 NXP
6  * Copyright 2024 Ideas on Board Oy
7  */
8 
9 #include <linux/device.h>
10 #include <linux/gpio/driver.h>
11 #include <linux/mfd/adp5585.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/regmap.h>
15 #include <linux/types.h>
16 
17 #define ADP5585_GPIO_MAX	11
18 
19 struct adp5585_gpio_dev {
20 	struct gpio_chip gpio_chip;
21 	struct regmap *regmap;
22 };
23 
adp5585_gpio_get_direction(struct gpio_chip * chip,unsigned int off)24 static int adp5585_gpio_get_direction(struct gpio_chip *chip, unsigned int off)
25 {
26 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
27 	unsigned int bank = ADP5585_BANK(off);
28 	unsigned int bit = ADP5585_BIT(off);
29 	unsigned int val;
30 
31 	regmap_read(adp5585_gpio->regmap, ADP5585_GPIO_DIRECTION_A + bank, &val);
32 
33 	return val & bit ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
34 }
35 
adp5585_gpio_direction_input(struct gpio_chip * chip,unsigned int off)36 static int adp5585_gpio_direction_input(struct gpio_chip *chip, unsigned int off)
37 {
38 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
39 	unsigned int bank = ADP5585_BANK(off);
40 	unsigned int bit = ADP5585_BIT(off);
41 
42 	return regmap_clear_bits(adp5585_gpio->regmap,
43 				 ADP5585_GPIO_DIRECTION_A + bank, bit);
44 }
45 
adp5585_gpio_direction_output(struct gpio_chip * chip,unsigned int off,int val)46 static int adp5585_gpio_direction_output(struct gpio_chip *chip, unsigned int off, int val)
47 {
48 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
49 	unsigned int bank = ADP5585_BANK(off);
50 	unsigned int bit = ADP5585_BIT(off);
51 	int ret;
52 
53 	ret = regmap_update_bits(adp5585_gpio->regmap,
54 				 ADP5585_GPO_DATA_OUT_A + bank, bit,
55 				 val ? bit : 0);
56 	if (ret)
57 		return ret;
58 
59 	return regmap_set_bits(adp5585_gpio->regmap,
60 			       ADP5585_GPIO_DIRECTION_A + bank, bit);
61 }
62 
adp5585_gpio_get_value(struct gpio_chip * chip,unsigned int off)63 static int adp5585_gpio_get_value(struct gpio_chip *chip, unsigned int off)
64 {
65 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
66 	unsigned int bank = ADP5585_BANK(off);
67 	unsigned int bit = ADP5585_BIT(off);
68 	unsigned int reg;
69 	unsigned int val;
70 
71 	/*
72 	 * The input status register doesn't reflect the pin state when the
73 	 * GPIO is configured as an output. Check the direction, and read the
74 	 * input status from GPI_STATUS or output value from GPO_DATA_OUT
75 	 * accordingly.
76 	 *
77 	 * We don't need any locking, as concurrent access to the same GPIO
78 	 * isn't allowed by the GPIO API, so there's no risk of the
79 	 * .direction_input(), .direction_output() or .set() operations racing
80 	 * with this.
81 	 */
82 	regmap_read(adp5585_gpio->regmap, ADP5585_GPIO_DIRECTION_A + bank, &val);
83 	reg = val & bit ? ADP5585_GPO_DATA_OUT_A : ADP5585_GPI_STATUS_A;
84 	regmap_read(adp5585_gpio->regmap, reg + bank, &val);
85 
86 	return !!(val & bit);
87 }
88 
adp5585_gpio_set_value(struct gpio_chip * chip,unsigned int off,int val)89 static int adp5585_gpio_set_value(struct gpio_chip *chip, unsigned int off,
90 				  int val)
91 {
92 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
93 	unsigned int bank = ADP5585_BANK(off);
94 	unsigned int bit = ADP5585_BIT(off);
95 
96 	return regmap_update_bits(adp5585_gpio->regmap,
97 				  ADP5585_GPO_DATA_OUT_A + bank,
98 				  bit, val ? bit : 0);
99 }
100 
adp5585_gpio_set_bias(struct adp5585_gpio_dev * adp5585_gpio,unsigned int off,unsigned int bias)101 static int adp5585_gpio_set_bias(struct adp5585_gpio_dev *adp5585_gpio,
102 				 unsigned int off, unsigned int bias)
103 {
104 	unsigned int bit, reg, mask, val;
105 
106 	/*
107 	 * The bias configuration fields are 2 bits wide and laid down in
108 	 * consecutive registers ADP5585_RPULL_CONFIG_*, with a hole of 4 bits
109 	 * after R5.
110 	 */
111 	bit = off * 2 + (off > 5 ? 4 : 0);
112 	reg = ADP5585_RPULL_CONFIG_A + bit / 8;
113 	mask = ADP5585_Rx_PULL_CFG_MASK << (bit % 8);
114 	val = bias << (bit % 8);
115 
116 	return regmap_update_bits(adp5585_gpio->regmap, reg, mask, val);
117 }
118 
adp5585_gpio_set_drive(struct adp5585_gpio_dev * adp5585_gpio,unsigned int off,enum pin_config_param drive)119 static int adp5585_gpio_set_drive(struct adp5585_gpio_dev *adp5585_gpio,
120 				  unsigned int off, enum pin_config_param drive)
121 {
122 	unsigned int bank = ADP5585_BANK(off);
123 	unsigned int bit = ADP5585_BIT(off);
124 
125 	return regmap_update_bits(adp5585_gpio->regmap,
126 				  ADP5585_GPO_OUT_MODE_A + bank, bit,
127 				  drive == PIN_CONFIG_DRIVE_OPEN_DRAIN ? bit : 0);
128 }
129 
adp5585_gpio_set_debounce(struct adp5585_gpio_dev * adp5585_gpio,unsigned int off,unsigned int debounce)130 static int adp5585_gpio_set_debounce(struct adp5585_gpio_dev *adp5585_gpio,
131 				     unsigned int off, unsigned int debounce)
132 {
133 	unsigned int bank = ADP5585_BANK(off);
134 	unsigned int bit = ADP5585_BIT(off);
135 
136 	return regmap_update_bits(adp5585_gpio->regmap,
137 				  ADP5585_DEBOUNCE_DIS_A + bank, bit,
138 				  debounce ? 0 : bit);
139 }
140 
adp5585_gpio_set_config(struct gpio_chip * chip,unsigned int off,unsigned long config)141 static int adp5585_gpio_set_config(struct gpio_chip *chip, unsigned int off,
142 				   unsigned long config)
143 {
144 	struct adp5585_gpio_dev *adp5585_gpio = gpiochip_get_data(chip);
145 	enum pin_config_param param = pinconf_to_config_param(config);
146 	u32 arg = pinconf_to_config_argument(config);
147 
148 	switch (param) {
149 	case PIN_CONFIG_BIAS_DISABLE:
150 		return adp5585_gpio_set_bias(adp5585_gpio, off,
151 					     ADP5585_Rx_PULL_CFG_DISABLE);
152 
153 	case PIN_CONFIG_BIAS_PULL_DOWN:
154 		return adp5585_gpio_set_bias(adp5585_gpio, off, arg ?
155 					     ADP5585_Rx_PULL_CFG_PD_300K :
156 					     ADP5585_Rx_PULL_CFG_DISABLE);
157 
158 	case PIN_CONFIG_BIAS_PULL_UP:
159 		return adp5585_gpio_set_bias(adp5585_gpio, off, arg ?
160 					     ADP5585_Rx_PULL_CFG_PU_300K :
161 					     ADP5585_Rx_PULL_CFG_DISABLE);
162 
163 	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
164 	case PIN_CONFIG_DRIVE_PUSH_PULL:
165 		return adp5585_gpio_set_drive(adp5585_gpio, off, param);
166 
167 	case PIN_CONFIG_INPUT_DEBOUNCE:
168 		return adp5585_gpio_set_debounce(adp5585_gpio, off, arg);
169 
170 	default:
171 		return -ENOTSUPP;
172 	};
173 }
174 
adp5585_gpio_probe(struct platform_device * pdev)175 static int adp5585_gpio_probe(struct platform_device *pdev)
176 {
177 	struct adp5585_dev *adp5585 = dev_get_drvdata(pdev->dev.parent);
178 	struct adp5585_gpio_dev *adp5585_gpio;
179 	struct device *dev = &pdev->dev;
180 	struct gpio_chip *gc;
181 	int ret;
182 
183 	adp5585_gpio = devm_kzalloc(dev, sizeof(*adp5585_gpio), GFP_KERNEL);
184 	if (!adp5585_gpio)
185 		return -ENOMEM;
186 
187 	adp5585_gpio->regmap = adp5585->regmap;
188 
189 	device_set_of_node_from_dev(dev, dev->parent);
190 
191 	gc = &adp5585_gpio->gpio_chip;
192 	gc->parent = dev;
193 	gc->get_direction = adp5585_gpio_get_direction;
194 	gc->direction_input = adp5585_gpio_direction_input;
195 	gc->direction_output = adp5585_gpio_direction_output;
196 	gc->get = adp5585_gpio_get_value;
197 	gc->set_rv = adp5585_gpio_set_value;
198 	gc->set_config = adp5585_gpio_set_config;
199 	gc->can_sleep = true;
200 
201 	gc->base = -1;
202 	gc->ngpio = ADP5585_GPIO_MAX;
203 	gc->label = pdev->name;
204 	gc->owner = THIS_MODULE;
205 
206 	ret = devm_gpiochip_add_data(dev, &adp5585_gpio->gpio_chip,
207 				     adp5585_gpio);
208 	if (ret)
209 		return dev_err_probe(dev, ret, "failed to add GPIO chip\n");
210 
211 	return 0;
212 }
213 
214 static const struct platform_device_id adp5585_gpio_id_table[] = {
215 	{ "adp5585-gpio" },
216 	{ /* Sentinel */ }
217 };
218 MODULE_DEVICE_TABLE(platform, adp5585_gpio_id_table);
219 
220 static struct platform_driver adp5585_gpio_driver = {
221 	.driver	= {
222 		.name = "adp5585-gpio",
223 	},
224 	.probe = adp5585_gpio_probe,
225 	.id_table = adp5585_gpio_id_table,
226 };
227 module_platform_driver(adp5585_gpio_driver);
228 
229 MODULE_AUTHOR("Haibo Chen <haibo.chen@nxp.com>");
230 MODULE_DESCRIPTION("GPIO ADP5585 Driver");
231 MODULE_LICENSE("GPL");
232