gpio-mb86s7x.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  linux/drivers/gpio/gpio-mb86s7x.c
  4 *
  5 *  Copyright (C) 2015 Fujitsu Semiconductor Limited
  6 *  Copyright (C) 2015 Linaro Ltd.
  7 */
  8
  9#include <linux/acpi.h>
 10#include <linux/io.h>
 11#include <linux/init.h>
 12#include <linux/clk.h>
 13#include <linux/mod_devicetable.h>
 14#include <linux/module.h>
 15#include <linux/err.h>
 16#include <linux/errno.h>
 17#include <linux/ioport.h>
 18#include <linux/gpio/driver.h>
 19#include <linux/platform_device.h>
 20#include <linux/spinlock.h>
 21#include <linux/slab.h>
 22
 23#include "gpiolib-acpi.h"
 24
 25/*
 26 * Only first 8bits of a register correspond to each pin,
 27 * so there are 4 registers for 32 pins.
 28 */
 29#define PDR(x)	(0x0 + x / 8 * 4)
 30#define DDR(x)	(0x10 + x / 8 * 4)
 31#define PFR(x)	(0x20 + x / 8 * 4)
 32
 33#define OFFSET(x)	BIT((x) % 8)
 34
 35struct mb86s70_gpio_chip {
 36	struct gpio_chip gc;
 37	void __iomem *base;
 38	spinlock_t lock;
 39};
 40
 41static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
 42{
 43	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 44	unsigned long flags;
 45	u32 val;
 46
 47	spin_lock_irqsave(&gchip->lock, flags);
 48
 49	val = readl(gchip->base + PFR(gpio));
 50	val &= ~OFFSET(gpio);
 51	writel(val, gchip->base + PFR(gpio));
 52
 53	spin_unlock_irqrestore(&gchip->lock, flags);
 54
 55	return 0;
 56}
 57
 58static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio)
 59{
 60	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 61	unsigned long flags;
 62	u32 val;
 63
 64	spin_lock_irqsave(&gchip->lock, flags);
 65
 66	val = readl(gchip->base + PFR(gpio));
 67	val |= OFFSET(gpio);
 68	writel(val, gchip->base + PFR(gpio));
 69
 70	spin_unlock_irqrestore(&gchip->lock, flags);
 71}
 72
 73static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
 74{
 75	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 76	unsigned long flags;
 77	unsigned char val;
 78
 79	spin_lock_irqsave(&gchip->lock, flags);
 80
 81	val = readl(gchip->base + DDR(gpio));
 82	val &= ~OFFSET(gpio);
 83	writel(val, gchip->base + DDR(gpio));
 84
 85	spin_unlock_irqrestore(&gchip->lock, flags);
 86
 87	return 0;
 88}
 89
 90static int mb86s70_gpio_direction_output(struct gpio_chip *gc,
 91					 unsigned gpio, int value)
 92{
 93	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 94	unsigned long flags;
 95	unsigned char val;
 96
 97	spin_lock_irqsave(&gchip->lock, flags);
 98
 99	val = readl(gchip->base + PDR(gpio));
100	if (value)
101		val |= OFFSET(gpio);
102	else
103		val &= ~OFFSET(gpio);
104	writel(val, gchip->base + PDR(gpio));
105
106	val = readl(gchip->base + DDR(gpio));
107	val |= OFFSET(gpio);
108	writel(val, gchip->base + DDR(gpio));
109
110	spin_unlock_irqrestore(&gchip->lock, flags);
111
112	return 0;
113}
114
115static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio)
116{
117	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
118
119	return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio));
120}
121
122static int mb86s70_gpio_set(struct gpio_chip *gc, unsigned int gpio, int value)
123{
124	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
125	unsigned long flags;
126	unsigned char val;
127
128	spin_lock_irqsave(&gchip->lock, flags);
129
130	val = readl(gchip->base + PDR(gpio));
131	if (value)
132		val |= OFFSET(gpio);
133	else
134		val &= ~OFFSET(gpio);
135	writel(val, gchip->base + PDR(gpio));
136
137	spin_unlock_irqrestore(&gchip->lock, flags);
138
139	return 0;
140}
141
142static int mb86s70_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
143{
144	int irq, index;
145
146	for (index = 0;; index++) {
147		irq = platform_get_irq(to_platform_device(gc->parent), index);
148		if (irq < 0)
149			return irq;
150		if (irq_get_irq_data(irq)->hwirq == offset)
151			return irq;
152	}
153	return -EINVAL;
154}
155
156static int mb86s70_gpio_probe(struct platform_device *pdev)
157{
158	struct mb86s70_gpio_chip *gchip;
159	struct clk *clk;
160	int ret;
161
162	gchip = devm_kzalloc(&pdev->dev, sizeof(*gchip), GFP_KERNEL);
163	if (gchip == NULL)
164		return -ENOMEM;
165
166	platform_set_drvdata(pdev, gchip);
167
168	gchip->base = devm_platform_ioremap_resource(pdev, 0);
169	if (IS_ERR(gchip->base))
170		return PTR_ERR(gchip->base);
171
172	clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
173	if (IS_ERR(clk))
174		return PTR_ERR(clk);
175
176	spin_lock_init(&gchip->lock);
177
178	gchip->gc.direction_output = mb86s70_gpio_direction_output;
179	gchip->gc.direction_input = mb86s70_gpio_direction_input;
180	gchip->gc.request = mb86s70_gpio_request;
181	gchip->gc.free = mb86s70_gpio_free;
182	gchip->gc.get = mb86s70_gpio_get;
183	gchip->gc.set = mb86s70_gpio_set;
184	gchip->gc.to_irq = mb86s70_gpio_to_irq;
185	gchip->gc.label = dev_name(&pdev->dev);
186	gchip->gc.ngpio = 32;
187	gchip->gc.owner = THIS_MODULE;
188	gchip->gc.parent = &pdev->dev;
189	gchip->gc.base = -1;
190
191	ret = gpiochip_add_data(&gchip->gc, gchip);
192	if (ret)
193		return dev_err_probe(&pdev->dev, ret,
194				     "couldn't register gpio driver\n");
195
196	acpi_gpiochip_request_interrupts(&gchip->gc);
197
198	return 0;
199}
200
201static void mb86s70_gpio_remove(struct platform_device *pdev)
202{
203	struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev);
204
205	acpi_gpiochip_free_interrupts(&gchip->gc);
206	gpiochip_remove(&gchip->gc);
207}
208
209static const struct of_device_id mb86s70_gpio_dt_ids[] = {
210	{ .compatible = "fujitsu,mb86s70-gpio" },
211	{ /* sentinel */ }
212};
213MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
214
215#ifdef CONFIG_ACPI
216static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = {
217	{ "SCX0007" },
218	{ /* sentinel */ }
219};
220MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids);
221#endif
222
223static struct platform_driver mb86s70_gpio_driver = {
224	.driver = {
225		.name = "mb86s70-gpio",
226		.of_match_table = mb86s70_gpio_dt_ids,
227		.acpi_match_table = ACPI_PTR(mb86s70_gpio_acpi_ids),
228	},
229	.probe = mb86s70_gpio_probe,
230	.remove = mb86s70_gpio_remove,
231};
232module_platform_driver(mb86s70_gpio_driver);
233
234MODULE_DESCRIPTION("MB86S7x GPIO Driver");
235MODULE_ALIAS("platform:mb86s70-gpio");
236MODULE_LICENSE("GPL");