1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * gpiolib support for Wolfson Arizona class devices |
4 | * |
5 | * Copyright 2012 Wolfson Microelectronics PLC. |
6 | * |
7 | * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> |
8 | */ |
9 | |
10 | #include <linux/gpio/driver.h> |
11 | #include <linux/kernel.h> |
12 | #include <linux/module.h> |
13 | #include <linux/platform_device.h> |
14 | #include <linux/pm_runtime.h> |
15 | #include <linux/slab.h> |
16 | |
17 | #include <linux/mfd/arizona/core.h> |
18 | #include <linux/mfd/arizona/pdata.h> |
19 | #include <linux/mfd/arizona/registers.h> |
20 | |
21 | struct arizona_gpio { |
22 | struct arizona *arizona; |
23 | struct gpio_chip gpio_chip; |
24 | }; |
25 | |
26 | static int arizona_gpio_direction_in(struct gpio_chip *chip, unsigned offset) |
27 | { |
28 | struct arizona_gpio *arizona_gpio = gpiochip_get_data(gc: chip); |
29 | struct arizona *arizona = arizona_gpio->arizona; |
30 | bool persistent = gpiochip_line_is_persistent(gc: chip, offset); |
31 | bool change; |
32 | int ret; |
33 | |
34 | ret = regmap_update_bits_check(map: arizona->regmap, |
35 | ARIZONA_GPIO1_CTRL + offset, |
36 | ARIZONA_GPN_DIR, ARIZONA_GPN_DIR, |
37 | change: &change); |
38 | if (ret < 0) |
39 | return ret; |
40 | |
41 | if (change && persistent) { |
42 | pm_runtime_mark_last_busy(dev: chip->parent); |
43 | pm_runtime_put_autosuspend(dev: chip->parent); |
44 | } |
45 | |
46 | return 0; |
47 | } |
48 | |
49 | static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset) |
50 | { |
51 | struct arizona_gpio *arizona_gpio = gpiochip_get_data(gc: chip); |
52 | struct arizona *arizona = arizona_gpio->arizona; |
53 | unsigned int reg, val; |
54 | int ret; |
55 | |
56 | reg = ARIZONA_GPIO1_CTRL + offset; |
57 | ret = regmap_read(map: arizona->regmap, reg, val: &val); |
58 | if (ret < 0) |
59 | return ret; |
60 | |
61 | /* Resume to read actual registers for input pins */ |
62 | if (val & ARIZONA_GPN_DIR) { |
63 | ret = pm_runtime_get_sync(dev: chip->parent); |
64 | if (ret < 0) { |
65 | dev_err(chip->parent, "Failed to resume: %d\n" , ret); |
66 | pm_runtime_put_autosuspend(dev: chip->parent); |
67 | return ret; |
68 | } |
69 | |
70 | /* Register is cached, drop it to ensure a physical read */ |
71 | ret = regcache_drop_region(map: arizona->regmap, min: reg, max: reg); |
72 | if (ret < 0) { |
73 | dev_err(chip->parent, "Failed to drop cache: %d\n" , |
74 | ret); |
75 | pm_runtime_put_autosuspend(dev: chip->parent); |
76 | return ret; |
77 | } |
78 | |
79 | ret = regmap_read(map: arizona->regmap, reg, val: &val); |
80 | if (ret < 0) { |
81 | pm_runtime_put_autosuspend(dev: chip->parent); |
82 | return ret; |
83 | } |
84 | |
85 | pm_runtime_mark_last_busy(dev: chip->parent); |
86 | pm_runtime_put_autosuspend(dev: chip->parent); |
87 | } |
88 | |
89 | if (val & ARIZONA_GPN_LVL) |
90 | return 1; |
91 | else |
92 | return 0; |
93 | } |
94 | |
95 | static int arizona_gpio_direction_out(struct gpio_chip *chip, |
96 | unsigned offset, int value) |
97 | { |
98 | struct arizona_gpio *arizona_gpio = gpiochip_get_data(gc: chip); |
99 | struct arizona *arizona = arizona_gpio->arizona; |
100 | bool persistent = gpiochip_line_is_persistent(gc: chip, offset); |
101 | unsigned int val; |
102 | int ret; |
103 | |
104 | ret = regmap_read(map: arizona->regmap, ARIZONA_GPIO1_CTRL + offset, val: &val); |
105 | if (ret < 0) |
106 | return ret; |
107 | |
108 | if ((val & ARIZONA_GPN_DIR) && persistent) { |
109 | ret = pm_runtime_get_sync(dev: chip->parent); |
110 | if (ret < 0) { |
111 | dev_err(chip->parent, "Failed to resume: %d\n" , ret); |
112 | pm_runtime_put(dev: chip->parent); |
113 | return ret; |
114 | } |
115 | } |
116 | |
117 | if (value) |
118 | value = ARIZONA_GPN_LVL; |
119 | |
120 | return regmap_update_bits(map: arizona->regmap, ARIZONA_GPIO1_CTRL + offset, |
121 | ARIZONA_GPN_DIR | ARIZONA_GPN_LVL, val: value); |
122 | } |
123 | |
124 | static void arizona_gpio_set(struct gpio_chip *chip, unsigned offset, int value) |
125 | { |
126 | struct arizona_gpio *arizona_gpio = gpiochip_get_data(gc: chip); |
127 | struct arizona *arizona = arizona_gpio->arizona; |
128 | |
129 | if (value) |
130 | value = ARIZONA_GPN_LVL; |
131 | |
132 | regmap_update_bits(map: arizona->regmap, ARIZONA_GPIO1_CTRL + offset, |
133 | ARIZONA_GPN_LVL, val: value); |
134 | } |
135 | |
136 | static const struct gpio_chip template_chip = { |
137 | .label = "arizona" , |
138 | .owner = THIS_MODULE, |
139 | .direction_input = arizona_gpio_direction_in, |
140 | .get = arizona_gpio_get, |
141 | .direction_output = arizona_gpio_direction_out, |
142 | .set = arizona_gpio_set, |
143 | .can_sleep = true, |
144 | }; |
145 | |
146 | static int arizona_gpio_probe(struct platform_device *pdev) |
147 | { |
148 | struct arizona *arizona = dev_get_drvdata(dev: pdev->dev.parent); |
149 | struct arizona_pdata *pdata = &arizona->pdata; |
150 | struct arizona_gpio *arizona_gpio; |
151 | int ret; |
152 | |
153 | device_set_node(dev: &pdev->dev, dev_fwnode(pdev->dev.parent)); |
154 | |
155 | arizona_gpio = devm_kzalloc(dev: &pdev->dev, size: sizeof(*arizona_gpio), |
156 | GFP_KERNEL); |
157 | if (!arizona_gpio) |
158 | return -ENOMEM; |
159 | |
160 | arizona_gpio->arizona = arizona; |
161 | arizona_gpio->gpio_chip = template_chip; |
162 | arizona_gpio->gpio_chip.parent = &pdev->dev; |
163 | |
164 | switch (arizona->type) { |
165 | case WM5102: |
166 | case WM5110: |
167 | case WM8280: |
168 | case WM8997: |
169 | case WM8998: |
170 | case WM1814: |
171 | arizona_gpio->gpio_chip.ngpio = 5; |
172 | break; |
173 | case WM1831: |
174 | case CS47L24: |
175 | arizona_gpio->gpio_chip.ngpio = 2; |
176 | break; |
177 | default: |
178 | dev_err(&pdev->dev, "Unknown chip variant %d\n" , |
179 | arizona->type); |
180 | return -EINVAL; |
181 | } |
182 | |
183 | if (pdata->gpio_base) |
184 | arizona_gpio->gpio_chip.base = pdata->gpio_base; |
185 | else |
186 | arizona_gpio->gpio_chip.base = -1; |
187 | |
188 | pm_runtime_enable(dev: &pdev->dev); |
189 | |
190 | ret = devm_gpiochip_add_data(&pdev->dev, &arizona_gpio->gpio_chip, |
191 | arizona_gpio); |
192 | if (ret < 0) { |
193 | pm_runtime_disable(dev: &pdev->dev); |
194 | dev_err(&pdev->dev, "Could not register gpiochip, %d\n" , |
195 | ret); |
196 | return ret; |
197 | } |
198 | |
199 | return 0; |
200 | } |
201 | |
202 | static struct platform_driver arizona_gpio_driver = { |
203 | .driver.name = "arizona-gpio" , |
204 | .probe = arizona_gpio_probe, |
205 | }; |
206 | |
207 | module_platform_driver(arizona_gpio_driver); |
208 | |
209 | MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>" ); |
210 | MODULE_DESCRIPTION("GPIO interface for Arizona devices" ); |
211 | MODULE_LICENSE("GPL" ); |
212 | MODULE_ALIAS("platform:arizona-gpio" ); |
213 | |