gpio-palmas.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * TI Palma series PMIC's GPIO driver.
  4 *
  5 * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
  6 *
  7 * Author: Laxman Dewangan <ldewangan@nvidia.com>
  8 */
  9
 10#include <linux/gpio/driver.h>
 11#include <linux/kernel.h>
 12#include <linux/init.h>
 13#include <linux/mfd/palmas.h>
 14#include <linux/of.h>
 15#include <linux/platform_device.h>
 16
 17struct palmas_gpio {
 18	struct gpio_chip gpio_chip;
 19	struct palmas *palmas;
 20};
 21
 22struct palmas_device_data {
 23	int ngpio;
 24};
 25
 26static int palmas_gpio_get(struct gpio_chip *gc, unsigned offset)
 27{
 28	struct palmas_gpio *pg = gpiochip_get_data(gc);
 29	struct palmas *palmas = pg->palmas;
 30	unsigned int val;
 31	int ret;
 32	unsigned int reg;
 33	int gpio16 = (offset/8);
 34
 35	offset %= 8;
 36	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
 37
 38	ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
 39	if (ret < 0) {
 40		dev_err(gc->parent, "Reg 0x%02x read failed, %d\n", reg, ret);
 41		return ret;
 42	}
 43
 44	if (val & BIT(offset))
 45		reg = (gpio16) ? PALMAS_GPIO_DATA_OUT2 : PALMAS_GPIO_DATA_OUT;
 46	else
 47		reg = (gpio16) ? PALMAS_GPIO_DATA_IN2 : PALMAS_GPIO_DATA_IN;
 48
 49	ret = palmas_read(palmas, PALMAS_GPIO_BASE, reg, &val);
 50	if (ret < 0) {
 51		dev_err(gc->parent, "Reg 0x%02x read failed, %d\n", reg, ret);
 52		return ret;
 53	}
 54	return !!(val & BIT(offset));
 55}
 56
 57static int palmas_gpio_set(struct gpio_chip *gc, unsigned int offset,
 58			   int value)
 59{
 60	struct palmas_gpio *pg = gpiochip_get_data(gc);
 61	struct palmas *palmas = pg->palmas;
 62	unsigned int reg;
 63	int gpio16 = (offset/8);
 64
 65	offset %= 8;
 66	if (gpio16)
 67		reg = (value) ?
 68			PALMAS_GPIO_SET_DATA_OUT2 : PALMAS_GPIO_CLEAR_DATA_OUT2;
 69	else
 70		reg = (value) ?
 71			PALMAS_GPIO_SET_DATA_OUT : PALMAS_GPIO_CLEAR_DATA_OUT;
 72
 73	return palmas_write(palmas, PALMAS_GPIO_BASE, reg, BIT(offset));
 74}
 75
 76static int palmas_gpio_output(struct gpio_chip *gc, unsigned offset,
 77				int value)
 78{
 79	struct palmas_gpio *pg = gpiochip_get_data(gc);
 80	struct palmas *palmas = pg->palmas;
 81	int ret;
 82	unsigned int reg;
 83	int gpio16 = (offset/8);
 84
 85	offset %= 8;
 86	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
 87
 88	/* Set the initial value */
 89	ret = palmas_gpio_set(gc, offset, value);
 90	if (ret)
 91		return ret;
 92
 93	ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg,
 94				BIT(offset), BIT(offset));
 95	if (ret < 0)
 96		dev_err(gc->parent, "Reg 0x%02x update failed, %d\n", reg,
 97			ret);
 98	return ret;
 99}
100
101static int palmas_gpio_input(struct gpio_chip *gc, unsigned offset)
102{
103	struct palmas_gpio *pg = gpiochip_get_data(gc);
104	struct palmas *palmas = pg->palmas;
105	int ret;
106	unsigned int reg;
107	int gpio16 = (offset/8);
108
109	offset %= 8;
110	reg = (gpio16) ? PALMAS_GPIO_DATA_DIR2 : PALMAS_GPIO_DATA_DIR;
111
112	ret = palmas_update_bits(palmas, PALMAS_GPIO_BASE, reg, BIT(offset), 0);
113	if (ret < 0)
114		dev_err(gc->parent, "Reg 0x%02x update failed, %d\n", reg,
115			ret);
116	return ret;
117}
118
119static int palmas_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
120{
121	struct palmas_gpio *pg = gpiochip_get_data(gc);
122	struct palmas *palmas = pg->palmas;
123
124	return palmas_irq_get_virq(palmas, PALMAS_GPIO_0_IRQ + offset);
125}
126
127static const struct palmas_device_data palmas_dev_data = {
128	.ngpio = 8,
129};
130
131static const struct palmas_device_data tps80036_dev_data = {
132	.ngpio = 16,
133};
134
135static const struct of_device_id of_palmas_gpio_match[] = {
136	{ .compatible = "ti,palmas-gpio", .data = &palmas_dev_data,},
137	{ .compatible = "ti,tps65913-gpio", .data = &palmas_dev_data,},
138	{ .compatible = "ti,tps65914-gpio", .data = &palmas_dev_data,},
139	{ .compatible = "ti,tps80036-gpio", .data = &tps80036_dev_data,},
140	{ },
141};
142MODULE_DEVICE_TABLE(of, of_palmas_gpio_match);
143
144static int palmas_gpio_probe(struct platform_device *pdev)
145{
146	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
147	struct palmas_platform_data *palmas_pdata;
148	struct palmas_gpio *palmas_gpio;
149	int ret;
150	const struct palmas_device_data *dev_data;
151
152	dev_data = of_device_get_match_data(&pdev->dev);
153	if (!dev_data)
154		dev_data = &palmas_dev_data;
155
156	palmas_gpio = devm_kzalloc(&pdev->dev,
157				sizeof(*palmas_gpio), GFP_KERNEL);
158	if (!palmas_gpio)
159		return -ENOMEM;
160
161	palmas_gpio->palmas = palmas;
162	palmas_gpio->gpio_chip.owner = THIS_MODULE;
163	palmas_gpio->gpio_chip.label = dev_name(&pdev->dev);
164	palmas_gpio->gpio_chip.ngpio = dev_data->ngpio;
165	palmas_gpio->gpio_chip.can_sleep = true;
166	palmas_gpio->gpio_chip.direction_input = palmas_gpio_input;
167	palmas_gpio->gpio_chip.direction_output = palmas_gpio_output;
168	palmas_gpio->gpio_chip.to_irq = palmas_gpio_to_irq;
169	palmas_gpio->gpio_chip.set	= palmas_gpio_set;
170	palmas_gpio->gpio_chip.get	= palmas_gpio_get;
171	palmas_gpio->gpio_chip.parent = &pdev->dev;
172
173	palmas_pdata = dev_get_platdata(palmas->dev);
174	if (palmas_pdata && palmas_pdata->gpio_base)
175		palmas_gpio->gpio_chip.base = palmas_pdata->gpio_base;
176	else
177		palmas_gpio->gpio_chip.base = -1;
178
179	ret = devm_gpiochip_add_data(&pdev->dev, &palmas_gpio->gpio_chip,
180				     palmas_gpio);
181	if (ret < 0) {
182		dev_err(&pdev->dev, "Could not register gpiochip, %d\n", ret);
183		return ret;
184	}
185
186	return ret;
187}
188
189static struct platform_driver palmas_gpio_driver = {
190	.driver.name	= "palmas-gpio",
191	.driver.of_match_table = of_palmas_gpio_match,
192	.probe		= palmas_gpio_probe,
193};
194
195static int __init palmas_gpio_init(void)
196{
197	return platform_driver_register(&palmas_gpio_driver);
198}
199subsys_initcall(palmas_gpio_init);
200
201static void __exit palmas_gpio_exit(void)
202{
203	platform_driver_unregister(&palmas_gpio_driver);
204}
205module_exit(palmas_gpio_exit);
206
207MODULE_DESCRIPTION("TI PALMAS series GPIO driver");
208MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
209MODULE_LICENSE("GPL");