gpio-adp5520.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * GPIO driver for Analog Devices ADP5520 MFD PMICs
  4 *
  5 * Copyright 2009 Analog Devices Inc.
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/slab.h>
 10#include <linux/kernel.h>
 11#include <linux/init.h>
 12#include <linux/platform_device.h>
 13#include <linux/mfd/adp5520.h>
 14#include <linux/gpio/driver.h>
 15
 16struct adp5520_gpio {
 17	struct device *master;
 18	struct gpio_chip gpio_chip;
 19	unsigned char lut[ADP5520_MAXGPIOS];
 20	unsigned long output;
 21};
 22
 23static int adp5520_gpio_get_value(struct gpio_chip *chip, unsigned off)
 24{
 25	struct adp5520_gpio *dev;
 26	uint8_t reg_val;
 27
 28	dev = gpiochip_get_data(chip);
 29
 30	/*
 31	 * There are dedicated registers for GPIO IN/OUT.
 32	 * Make sure we return the right value, even when configured as output
 33	 */
 34
 35	if (test_bit(off, &dev->output))
 36		adp5520_read(dev->master, ADP5520_GPIO_OUT, &reg_val);
 37	else
 38		adp5520_read(dev->master, ADP5520_GPIO_IN, &reg_val);
 39
 40	return !!(reg_val & dev->lut[off]);
 41}
 42
 43static int adp5520_gpio_set_value(struct gpio_chip *chip,
 44				  unsigned int off, int val)
 45{
 46	struct adp5520_gpio *dev;
 47	dev = gpiochip_get_data(chip);
 48
 49	if (val)
 50		return adp5520_set_bits(dev->master, ADP5520_GPIO_OUT,
 51					dev->lut[off]);
 52	else
 53		return adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT,
 54					dev->lut[off]);
 55}
 56
 57static int adp5520_gpio_direction_input(struct gpio_chip *chip, unsigned off)
 58{
 59	struct adp5520_gpio *dev;
 60	dev = gpiochip_get_data(chip);
 61
 62	clear_bit(off, &dev->output);
 63
 64	return adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_2,
 65				dev->lut[off]);
 66}
 67
 68static int adp5520_gpio_direction_output(struct gpio_chip *chip,
 69		unsigned off, int val)
 70{
 71	struct adp5520_gpio *dev;
 72	int ret = 0;
 73	dev = gpiochip_get_data(chip);
 74
 75	set_bit(off, &dev->output);
 76
 77	if (val)
 78		ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_OUT,
 79					dev->lut[off]);
 80	else
 81		ret |= adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT,
 82					dev->lut[off]);
 83
 84	ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_CFG_2,
 85					dev->lut[off]);
 86
 87	return ret;
 88}
 89
 90static int adp5520_gpio_probe(struct platform_device *pdev)
 91{
 92	struct adp5520_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
 93	struct adp5520_gpio *dev;
 94	struct gpio_chip *gc;
 95	int ret, i, gpios;
 96	unsigned char ctl_mask = 0;
 97
 98	if (pdata == NULL) {
 99		dev_err(&pdev->dev, "missing platform data\n");
100		return -ENODEV;
101	}
102
103	if (pdev->id != ID_ADP5520) {
104		dev_err(&pdev->dev, "only ADP5520 supports GPIO\n");
105		return -ENODEV;
106	}
107
108	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
109	if (dev == NULL)
110		return -ENOMEM;
111
112	dev->master = pdev->dev.parent;
113
114	for (gpios = 0, i = 0; i < ADP5520_MAXGPIOS; i++)
115		if (pdata->gpio_en_mask & (1 << i))
116			dev->lut[gpios++] = 1 << i;
117
118	if (gpios < 1)
119		return -EINVAL;
120
121	gc = &dev->gpio_chip;
122	gc->direction_input  = adp5520_gpio_direction_input;
123	gc->direction_output = adp5520_gpio_direction_output;
124	gc->get = adp5520_gpio_get_value;
125	gc->set = adp5520_gpio_set_value;
126	gc->can_sleep = true;
127
128	gc->base = pdata->gpio_start;
129	gc->ngpio = gpios;
130	gc->label = pdev->name;
131	gc->owner = THIS_MODULE;
132
133	ret = adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_1,
134		pdata->gpio_en_mask);
135
136	if (pdata->gpio_en_mask & ADP5520_GPIO_C3)
137		ctl_mask |= ADP5520_C3_MODE;
138
139	if (pdata->gpio_en_mask & ADP5520_GPIO_R3)
140		ctl_mask |= ADP5520_R3_MODE;
141
142	if (ctl_mask)
143		ret = adp5520_set_bits(dev->master, ADP5520_LED_CONTROL,
144			ctl_mask);
145
146	ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_PULLUP,
147		pdata->gpio_pullup_mask);
148
149	if (ret) {
150		dev_err(&pdev->dev, "failed to write\n");
151		return ret;
152	}
153
154	return devm_gpiochip_add_data(&pdev->dev, &dev->gpio_chip, dev);
155}
156
157static struct platform_driver adp5520_gpio_driver = {
158	.driver	= {
159		.name	= "adp5520-gpio",
160	},
161	.probe		= adp5520_gpio_probe,
162};
163
164module_platform_driver(adp5520_gpio_driver);
165
166MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
167MODULE_DESCRIPTION("GPIO ADP5520 Driver");
168MODULE_LICENSE("GPL");
169MODULE_ALIAS("platform:adp5520-gpio");