1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Dialog DA9062 pinctrl and GPIO driver.
4 * Based on DA9055 GPIO driver.
5 *
6 * TODO:
7 * - add pinmux and pinctrl support (gpio alternate mode)
8 *
9 * Documents:
10 * [1] https://www.dialog-semiconductor.com/sites/default/files/da9062_datasheet_3v6.pdf
11 *
12 * Copyright (C) 2019 Pengutronix, Marco Felsch <kernel@pengutronix.de>
13 */
14 #include <linux/bits.h>
15 #include <linux/module.h>
16 #include <linux/platform_device.h>
17 #include <linux/regmap.h>
18
19 #include <linux/gpio/driver.h>
20
21 #include <linux/mfd/da9062/core.h>
22 #include <linux/mfd/da9062/registers.h>
23
24 /*
25 * We need this get the gpio_desc from a <gpio_chip,offset> tuple to decide if
26 * the gpio is active low without a vendor specific dt-binding.
27 */
28 #include "../gpio/gpiolib.h"
29
30 #define DA9062_TYPE(offset) (4 * (offset % 2))
31 #define DA9062_PIN_SHIFT(offset) (4 * (offset % 2))
32 #define DA9062_PIN_ALTERNATE 0x00 /* gpio alternate mode */
33 #define DA9062_PIN_GPI 0x01 /* gpio in */
34 #define DA9062_PIN_GPO_OD 0x02 /* gpio out open-drain */
35 #define DA9062_PIN_GPO_PP 0x03 /* gpio out push-pull */
36 #define DA9062_GPIO_NUM 5
37
38 struct da9062_pctl {
39 struct da9062 *da9062;
40 struct gpio_chip gc;
41 unsigned int pin_config[DA9062_GPIO_NUM];
42 };
43
da9062_pctl_get_pin_mode(struct da9062_pctl * pctl,unsigned int offset)44 static int da9062_pctl_get_pin_mode(struct da9062_pctl *pctl,
45 unsigned int offset)
46 {
47 struct regmap *regmap = pctl->da9062->regmap;
48 int ret, val;
49
50 ret = regmap_read(regmap, DA9062AA_GPIO_0_1 + (offset >> 1), &val);
51 if (ret < 0)
52 return ret;
53
54 val >>= DA9062_PIN_SHIFT(offset);
55 val &= DA9062AA_GPIO0_PIN_MASK;
56
57 return val;
58 }
59
da9062_pctl_set_pin_mode(struct da9062_pctl * pctl,unsigned int offset,unsigned int mode_req)60 static int da9062_pctl_set_pin_mode(struct da9062_pctl *pctl,
61 unsigned int offset, unsigned int mode_req)
62 {
63 struct regmap *regmap = pctl->da9062->regmap;
64 unsigned int mode = mode_req;
65 unsigned int mask;
66 int ret;
67
68 mode &= DA9062AA_GPIO0_PIN_MASK;
69 mode <<= DA9062_PIN_SHIFT(offset);
70 mask = DA9062AA_GPIO0_PIN_MASK << DA9062_PIN_SHIFT(offset);
71
72 ret = regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >> 1),
73 mask, mode);
74 if (!ret)
75 pctl->pin_config[offset] = mode_req;
76
77 return ret;
78 }
79
da9062_gpio_get(struct gpio_chip * gc,unsigned int offset)80 static int da9062_gpio_get(struct gpio_chip *gc, unsigned int offset)
81 {
82 struct da9062_pctl *pctl = gpiochip_get_data(gc);
83 struct regmap *regmap = pctl->da9062->regmap;
84 int gpio_mode, val;
85 int ret;
86
87 gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
88 if (gpio_mode < 0)
89 return gpio_mode;
90
91 switch (gpio_mode) {
92 case DA9062_PIN_ALTERNATE:
93 return -ENOTSUPP;
94 case DA9062_PIN_GPI:
95 ret = regmap_read(regmap, DA9062AA_STATUS_B, &val);
96 if (ret < 0)
97 return ret;
98 break;
99 case DA9062_PIN_GPO_OD:
100 case DA9062_PIN_GPO_PP:
101 ret = regmap_read(regmap, DA9062AA_GPIO_MODE0_4, &val);
102 if (ret < 0)
103 return ret;
104 }
105
106 return !!(val & BIT(offset));
107 }
108
da9062_gpio_set(struct gpio_chip * gc,unsigned int offset,int value)109 static void da9062_gpio_set(struct gpio_chip *gc, unsigned int offset,
110 int value)
111 {
112 struct da9062_pctl *pctl = gpiochip_get_data(gc);
113 struct regmap *regmap = pctl->da9062->regmap;
114
115 regmap_update_bits(regmap, DA9062AA_GPIO_MODE0_4, BIT(offset),
116 value << offset);
117 }
118
da9062_gpio_get_direction(struct gpio_chip * gc,unsigned int offset)119 static int da9062_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
120 {
121 struct da9062_pctl *pctl = gpiochip_get_data(gc);
122 int gpio_mode;
123
124 gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
125 if (gpio_mode < 0)
126 return gpio_mode;
127
128 switch (gpio_mode) {
129 case DA9062_PIN_ALTERNATE:
130 return -ENOTSUPP;
131 case DA9062_PIN_GPI:
132 return GPIO_LINE_DIRECTION_IN;
133 case DA9062_PIN_GPO_OD:
134 case DA9062_PIN_GPO_PP:
135 return GPIO_LINE_DIRECTION_OUT;
136 }
137
138 return -EINVAL;
139 }
140
da9062_gpio_direction_input(struct gpio_chip * gc,unsigned int offset)141 static int da9062_gpio_direction_input(struct gpio_chip *gc,
142 unsigned int offset)
143 {
144 struct da9062_pctl *pctl = gpiochip_get_data(gc);
145 struct regmap *regmap = pctl->da9062->regmap;
146 struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
147 unsigned int gpi_type;
148 int ret;
149
150 ret = da9062_pctl_set_pin_mode(pctl, offset, DA9062_PIN_GPI);
151 if (ret)
152 return ret;
153
154 /*
155 * If the gpio is active low we should set it in hw too. No worries
156 * about gpio_get() because we read and return the gpio-level. So the
157 * gpiolib active_low handling is still correct.
158 *
159 * 0 - active low, 1 - active high
160 */
161 gpi_type = !gpiod_is_active_low(desc);
162
163 return regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >> 1),
164 DA9062AA_GPIO0_TYPE_MASK << DA9062_TYPE(offset),
165 gpi_type << DA9062_TYPE(offset));
166 }
167
da9062_gpio_direction_output(struct gpio_chip * gc,unsigned int offset,int value)168 static int da9062_gpio_direction_output(struct gpio_chip *gc,
169 unsigned int offset, int value)
170 {
171 struct da9062_pctl *pctl = gpiochip_get_data(gc);
172 unsigned int pin_config = pctl->pin_config[offset];
173 int ret;
174
175 ret = da9062_pctl_set_pin_mode(pctl, offset, pin_config);
176 if (ret)
177 return ret;
178
179 da9062_gpio_set(gc, offset, value);
180
181 return 0;
182 }
183
da9062_gpio_set_config(struct gpio_chip * gc,unsigned int offset,unsigned long config)184 static int da9062_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
185 unsigned long config)
186 {
187 struct da9062_pctl *pctl = gpiochip_get_data(gc);
188 struct regmap *regmap = pctl->da9062->regmap;
189 int gpio_mode;
190
191 /*
192 * We need to meet the following restrictions [1, Figure 18]:
193 * - PIN_CONFIG_BIAS_PULL_DOWN -> only allowed if the pin is used as
194 * gpio input
195 * - PIN_CONFIG_BIAS_PULL_UP -> only allowed if the pin is used as
196 * gpio output open-drain.
197 */
198
199 switch (pinconf_to_config_param(config)) {
200 case PIN_CONFIG_BIAS_DISABLE:
201 return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
202 BIT(offset), 0);
203 case PIN_CONFIG_BIAS_PULL_DOWN:
204 gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
205 if (gpio_mode < 0)
206 return -EINVAL;
207 else if (gpio_mode != DA9062_PIN_GPI)
208 return -ENOTSUPP;
209 return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
210 BIT(offset), BIT(offset));
211 case PIN_CONFIG_BIAS_PULL_UP:
212 gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
213 if (gpio_mode < 0)
214 return -EINVAL;
215 else if (gpio_mode != DA9062_PIN_GPO_OD)
216 return -ENOTSUPP;
217 return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
218 BIT(offset), BIT(offset));
219 case PIN_CONFIG_DRIVE_OPEN_DRAIN:
220 return da9062_pctl_set_pin_mode(pctl, offset,
221 DA9062_PIN_GPO_OD);
222 case PIN_CONFIG_DRIVE_PUSH_PULL:
223 return da9062_pctl_set_pin_mode(pctl, offset,
224 DA9062_PIN_GPO_PP);
225 default:
226 return -ENOTSUPP;
227 }
228 }
229
da9062_gpio_to_irq(struct gpio_chip * gc,unsigned int offset)230 static int da9062_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
231 {
232 struct da9062_pctl *pctl = gpiochip_get_data(gc);
233 struct da9062 *da9062 = pctl->da9062;
234
235 return regmap_irq_get_virq(da9062->regmap_irq,
236 DA9062_IRQ_GPI0 + offset);
237 }
238
239 static const struct gpio_chip reference_gc = {
240 .owner = THIS_MODULE,
241 .get = da9062_gpio_get,
242 .set = da9062_gpio_set,
243 .get_direction = da9062_gpio_get_direction,
244 .direction_input = da9062_gpio_direction_input,
245 .direction_output = da9062_gpio_direction_output,
246 .set_config = da9062_gpio_set_config,
247 .to_irq = da9062_gpio_to_irq,
248 .can_sleep = true,
249 .ngpio = DA9062_GPIO_NUM,
250 .base = -1,
251 };
252
da9062_pctl_probe(struct platform_device * pdev)253 static int da9062_pctl_probe(struct platform_device *pdev)
254 {
255 struct device *parent = pdev->dev.parent;
256 struct da9062_pctl *pctl;
257 int i;
258
259 pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
260 if (!pctl)
261 return -ENOMEM;
262
263 pctl->da9062 = dev_get_drvdata(parent);
264 if (!pctl->da9062)
265 return -EINVAL;
266
267 if (!device_property_present(parent, "gpio-controller"))
268 return 0;
269
270 for (i = 0; i < ARRAY_SIZE(pctl->pin_config); i++)
271 pctl->pin_config[i] = DA9062_PIN_GPO_PP;
272
273 /*
274 * Currently the driver handles only the GPIO support. The
275 * pinctrl/pinmux support can be added later if needed.
276 */
277 pctl->gc = reference_gc;
278 pctl->gc.label = dev_name(&pdev->dev);
279 pctl->gc.parent = &pdev->dev;
280 #ifdef CONFIG_OF_GPIO
281 pctl->gc.of_node = parent->of_node;
282 #endif
283
284 platform_set_drvdata(pdev, pctl);
285
286 return devm_gpiochip_add_data(&pdev->dev, &pctl->gc, pctl);
287 }
288
289 static struct platform_driver da9062_pctl_driver = {
290 .probe = da9062_pctl_probe,
291 .driver = {
292 .name = "da9062-gpio",
293 },
294 };
295 module_platform_driver(da9062_pctl_driver);
296
297 MODULE_AUTHOR("Marco Felsch <kernel@pengutronix.de>");
298 MODULE_DESCRIPTION("DA9062 PMIC pinctrl and GPIO Driver");
299 MODULE_LICENSE("GPL v2");
300 MODULE_ALIAS("platform:da9062-gpio");
301