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/property.h>
18#include <linux/regmap.h>
19
20#include <linux/gpio/consumer.h>
21#include <linux/gpio/driver.h>
22
23#include <linux/mfd/da9062/core.h>
24#include <linux/mfd/da9062/registers.h>
25
26#define DA9062_TYPE(offset)		(4 * (offset % 2))
27#define DA9062_PIN_SHIFT(offset)	(4 * (offset % 2))
28#define DA9062_PIN_ALTERNATE		0x00 /* gpio alternate mode */
29#define DA9062_PIN_GPI			0x01 /* gpio in */
30#define DA9062_PIN_GPO_OD		0x02 /* gpio out open-drain */
31#define DA9062_PIN_GPO_PP		0x03 /* gpio out push-pull */
32#define DA9062_GPIO_NUM			5
33
34struct da9062_pctl {
35	struct da9062 *da9062;
36	struct gpio_chip gc;
37	unsigned int pin_config[DA9062_GPIO_NUM];
38};
39
40static int da9062_pctl_get_pin_mode(struct da9062_pctl *pctl,
41				    unsigned int offset)
42{
43	struct regmap *regmap = pctl->da9062->regmap;
44	int ret, val;
45
46	ret = regmap_read(regmap, DA9062AA_GPIO_0_1 + (offset >> 1), &val);
47	if (ret < 0)
48		return ret;
49
50	val >>= DA9062_PIN_SHIFT(offset);
51	val &= DA9062AA_GPIO0_PIN_MASK;
52
53	return val;
54}
55
56static int da9062_pctl_set_pin_mode(struct da9062_pctl *pctl,
57				    unsigned int offset, unsigned int mode_req)
58{
59	struct regmap *regmap = pctl->da9062->regmap;
60	unsigned int mode = mode_req;
61	unsigned int mask;
62	int ret;
63
64	mode &= DA9062AA_GPIO0_PIN_MASK;
65	mode <<= DA9062_PIN_SHIFT(offset);
66	mask = DA9062AA_GPIO0_PIN_MASK << DA9062_PIN_SHIFT(offset);
67
68	ret = regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >> 1),
69				 mask, mode);
70	if (!ret)
71		pctl->pin_config[offset] = mode_req;
72
73	return ret;
74}
75
76static int da9062_gpio_get(struct gpio_chip *gc, unsigned int offset)
77{
78	struct da9062_pctl *pctl = gpiochip_get_data(gc);
79	struct regmap *regmap = pctl->da9062->regmap;
80	int gpio_mode, val;
81	int ret;
82
83	gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
84	if (gpio_mode < 0)
85		return gpio_mode;
86
87	switch (gpio_mode) {
88	case DA9062_PIN_ALTERNATE:
89		return -ENOTSUPP;
90	case DA9062_PIN_GPI:
91		ret = regmap_read(regmap, DA9062AA_STATUS_B, &val);
92		if (ret < 0)
93			return ret;
94		break;
95	case DA9062_PIN_GPO_OD:
96	case DA9062_PIN_GPO_PP:
97		ret = regmap_read(regmap, DA9062AA_GPIO_MODE0_4, &val);
98		if (ret < 0)
99			return ret;
100	}
101
102	return !!(val & BIT(offset));
103}
104
105static void da9062_gpio_set(struct gpio_chip *gc, unsigned int offset,
106			    int value)
107{
108	struct da9062_pctl *pctl = gpiochip_get_data(gc);
109	struct regmap *regmap = pctl->da9062->regmap;
110
111	regmap_update_bits(regmap, DA9062AA_GPIO_MODE0_4, BIT(offset),
112			   value << offset);
113}
114
115static int da9062_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
116{
117	struct da9062_pctl *pctl = gpiochip_get_data(gc);
118	int gpio_mode;
119
120	gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
121	if (gpio_mode < 0)
122		return gpio_mode;
123
124	switch (gpio_mode) {
125	case DA9062_PIN_ALTERNATE:
126		return -ENOTSUPP;
127	case DA9062_PIN_GPI:
128		return GPIO_LINE_DIRECTION_IN;
129	case DA9062_PIN_GPO_OD:
130	case DA9062_PIN_GPO_PP:
131		return GPIO_LINE_DIRECTION_OUT;
132	}
133
134	return -EINVAL;
135}
136
137static int da9062_gpio_direction_input(struct gpio_chip *gc,
138				       unsigned int offset)
139{
140	struct da9062_pctl *pctl = gpiochip_get_data(gc);
141	struct regmap *regmap = pctl->da9062->regmap;
142	struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
143	unsigned int gpi_type;
144	int ret;
145
146	ret = da9062_pctl_set_pin_mode(pctl, offset, DA9062_PIN_GPI);
147	if (ret)
148		return ret;
149
150	/*
151	 * If the gpio is active low we should set it in hw too. No worries
152	 * about gpio_get() because we read and return the gpio-level. So the
153	 * gpiolib active_low handling is still correct.
154	 *
155	 * 0 - active low, 1 - active high
156	 */
157	gpi_type = !gpiod_is_active_low(desc);
158
159	return regmap_update_bits(regmap, DA9062AA_GPIO_0_1 + (offset >> 1),
160				DA9062AA_GPIO0_TYPE_MASK << DA9062_TYPE(offset),
161				gpi_type << DA9062_TYPE(offset));
162}
163
164static int da9062_gpio_direction_output(struct gpio_chip *gc,
165					unsigned int offset, int value)
166{
167	struct da9062_pctl *pctl = gpiochip_get_data(gc);
168	unsigned int pin_config = pctl->pin_config[offset];
169	int ret;
170
171	ret = da9062_pctl_set_pin_mode(pctl, offset, pin_config);
172	if (ret)
173		return ret;
174
175	da9062_gpio_set(gc, offset, value);
176
177	return 0;
178}
179
180static int da9062_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
181				  unsigned long config)
182{
183	struct da9062_pctl *pctl = gpiochip_get_data(gc);
184	struct regmap *regmap = pctl->da9062->regmap;
185	int gpio_mode;
186
187	/*
188	 * We need to meet the following restrictions [1, Figure 18]:
189	 * - PIN_CONFIG_BIAS_PULL_DOWN -> only allowed if the pin is used as
190	 *				  gpio input
191	 * - PIN_CONFIG_BIAS_PULL_UP   -> only allowed if the pin is used as
192	 *				  gpio output open-drain.
193	 */
194
195	switch (pinconf_to_config_param(config)) {
196	case PIN_CONFIG_BIAS_DISABLE:
197		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
198					  BIT(offset), 0);
199	case PIN_CONFIG_BIAS_PULL_DOWN:
200		gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
201		if (gpio_mode < 0)
202			return -EINVAL;
203		else if (gpio_mode != DA9062_PIN_GPI)
204			return -ENOTSUPP;
205		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
206					  BIT(offset), BIT(offset));
207	case PIN_CONFIG_BIAS_PULL_UP:
208		gpio_mode = da9062_pctl_get_pin_mode(pctl, offset);
209		if (gpio_mode < 0)
210			return -EINVAL;
211		else if (gpio_mode != DA9062_PIN_GPO_OD)
212			return -ENOTSUPP;
213		return regmap_update_bits(regmap, DA9062AA_CONFIG_K,
214					  BIT(offset), BIT(offset));
215	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
216		return da9062_pctl_set_pin_mode(pctl, offset,
217						DA9062_PIN_GPO_OD);
218	case PIN_CONFIG_DRIVE_PUSH_PULL:
219		return da9062_pctl_set_pin_mode(pctl, offset,
220						DA9062_PIN_GPO_PP);
221	default:
222		return -ENOTSUPP;
223	}
224}
225
226static int da9062_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
227{
228	struct da9062_pctl *pctl = gpiochip_get_data(gc);
229	struct da9062 *da9062 = pctl->da9062;
230
231	return regmap_irq_get_virq(da9062->regmap_irq,
232				   DA9062_IRQ_GPI0 + offset);
233}
234
235static const struct gpio_chip reference_gc = {
236	.owner = THIS_MODULE,
237	.get = da9062_gpio_get,
238	.set = da9062_gpio_set,
239	.get_direction = da9062_gpio_get_direction,
240	.direction_input = da9062_gpio_direction_input,
241	.direction_output = da9062_gpio_direction_output,
242	.set_config = da9062_gpio_set_config,
243	.to_irq = da9062_gpio_to_irq,
244	.can_sleep = true,
245	.ngpio = DA9062_GPIO_NUM,
246	.base = -1,
247};
248
249static int da9062_pctl_probe(struct platform_device *pdev)
250{
251	struct device *parent = pdev->dev.parent;
252	struct da9062_pctl *pctl;
253	int i;
254
255	device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));
256
257	pctl = devm_kzalloc(&pdev->dev, sizeof(*pctl), GFP_KERNEL);
258	if (!pctl)
259		return -ENOMEM;
260
261	pctl->da9062 = dev_get_drvdata(parent);
262	if (!pctl->da9062)
263		return -EINVAL;
264
265	if (!device_property_present(parent, "gpio-controller"))
266		return 0;
267
268	for (i = 0; i < ARRAY_SIZE(pctl->pin_config); i++)
269		pctl->pin_config[i] = DA9062_PIN_GPO_PP;
270
271	/*
272	 * Currently the driver handles only the GPIO support. The
273	 * pinctrl/pinmux support can be added later if needed.
274	 */
275	pctl->gc = reference_gc;
276	pctl->gc.label = dev_name(&pdev->dev);
277	pctl->gc.parent = &pdev->dev;
278
279	platform_set_drvdata(pdev, pctl);
280
281	return devm_gpiochip_add_data(&pdev->dev, &pctl->gc, pctl);
282}
283
284static const struct of_device_id da9062_compatible_reg_id_table[] = {
285	{ .compatible = "dlg,da9062-gpio" },
286	{ }
287};
288MODULE_DEVICE_TABLE(of, da9062_compatible_reg_id_table);
289
290static struct platform_driver da9062_pctl_driver = {
291	.probe = da9062_pctl_probe,
292	.driver = {
293		.name	= "da9062-gpio",
294		.of_match_table = da9062_compatible_reg_id_table,
295	},
296};
297module_platform_driver(da9062_pctl_driver);
298
299MODULE_AUTHOR("Marco Felsch <kernel@pengutronix.de>");
300MODULE_DESCRIPTION("DA9062 PMIC pinctrl and GPIO Driver");
301MODULE_LICENSE("GPL v2");
302MODULE_ALIAS("platform:da9062-gpio");
303