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/module.h>
 14#include <linux/err.h>
 15#include <linux/errno.h>
 16#include <linux/ioport.h>
 17#include <linux/of_device.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.h"
 24#include "gpiolib-acpi.h"
 25
 26/*
 27 * Only first 8bits of a register correspond to each pin,
 28 * so there are 4 registers for 32 pins.
 29 */
 30#define PDR(x)	(0x0 + x / 8 * 4)
 31#define DDR(x)	(0x10 + x / 8 * 4)
 32#define PFR(x)	(0x20 + x / 8 * 4)
 33
 34#define OFFSET(x)	BIT((x) % 8)
 35
 36struct mb86s70_gpio_chip {
 37	struct gpio_chip gc;
 38	void __iomem *base;
 39	struct clk *clk;
 40	spinlock_t lock;
 41};
 42
 43static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
 44{
 45	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 46	unsigned long flags;
 47	u32 val;
 48
 49	spin_lock_irqsave(&gchip->lock, flags);
 50
 51	val = readl(gchip->base + PFR(gpio));
 52	val &= ~OFFSET(gpio);
 53	writel(val, gchip->base + PFR(gpio));
 54
 55	spin_unlock_irqrestore(&gchip->lock, flags);
 56
 57	return 0;
 58}
 59
 60static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio)
 61{
 62	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 63	unsigned long flags;
 64	u32 val;
 65
 66	spin_lock_irqsave(&gchip->lock, flags);
 67
 68	val = readl(gchip->base + PFR(gpio));
 69	val |= OFFSET(gpio);
 70	writel(val, gchip->base + PFR(gpio));
 71
 72	spin_unlock_irqrestore(&gchip->lock, flags);
 73}
 74
 75static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
 76{
 77	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 78	unsigned long flags;
 79	unsigned char val;
 80
 81	spin_lock_irqsave(&gchip->lock, flags);
 82
 83	val = readl(gchip->base + DDR(gpio));
 84	val &= ~OFFSET(gpio);
 85	writel(val, gchip->base + DDR(gpio));
 86
 87	spin_unlock_irqrestore(&gchip->lock, flags);
 88
 89	return 0;
 90}
 91
 92static int mb86s70_gpio_direction_output(struct gpio_chip *gc,
 93					 unsigned gpio, int value)
 94{
 95	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
 96	unsigned long flags;
 97	unsigned char val;
 98
 99	spin_lock_irqsave(&gchip->lock, flags);
100
101	val = readl(gchip->base + PDR(gpio));
102	if (value)
103		val |= OFFSET(gpio);
104	else
105		val &= ~OFFSET(gpio);
106	writel(val, gchip->base + PDR(gpio));
107
108	val = readl(gchip->base + DDR(gpio));
109	val |= OFFSET(gpio);
110	writel(val, gchip->base + DDR(gpio));
111
112	spin_unlock_irqrestore(&gchip->lock, flags);
113
114	return 0;
115}
116
117static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio)
118{
119	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
120
121	return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio));
122}
123
124static void mb86s70_gpio_set(struct gpio_chip *gc, unsigned gpio, int value)
125{
126	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
127	unsigned long flags;
128	unsigned char val;
129
130	spin_lock_irqsave(&gchip->lock, flags);
131
132	val = readl(gchip->base + PDR(gpio));
133	if (value)
134		val |= OFFSET(gpio);
135	else
136		val &= ~OFFSET(gpio);
137	writel(val, gchip->base + PDR(gpio));
138
139	spin_unlock_irqrestore(&gchip->lock, flags);
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 == 0)
151			break;
152		if (irq_get_irq_data(irq)->hwirq == offset)
153			return irq;
154	}
155	return -EINVAL;
156}
157
158static int mb86s70_gpio_probe(struct platform_device *pdev)
159{
160	struct mb86s70_gpio_chip *gchip;
161	int ret;
162
163	gchip = devm_kzalloc(&pdev->dev, sizeof(*gchip), GFP_KERNEL);
164	if (gchip == NULL)
165		return -ENOMEM;
166
167	platform_set_drvdata(pdev, gchip);
168
169	gchip->base = devm_platform_ioremap_resource(pdev, 0);
170	if (IS_ERR(gchip->base))
171		return PTR_ERR(gchip->base);
172
173	gchip->clk = devm_clk_get_optional(&pdev->dev, NULL);
174	if (IS_ERR(gchip->clk))
175		return PTR_ERR(gchip->clk);
176
177	ret = clk_prepare_enable(gchip->clk);
178	if (ret)
179		return ret;
180
181	spin_lock_init(&gchip->lock);
182
183	gchip->gc.direction_output = mb86s70_gpio_direction_output;
184	gchip->gc.direction_input = mb86s70_gpio_direction_input;
185	gchip->gc.request = mb86s70_gpio_request;
186	gchip->gc.free = mb86s70_gpio_free;
187	gchip->gc.get = mb86s70_gpio_get;
188	gchip->gc.set = mb86s70_gpio_set;
189	gchip->gc.to_irq = mb86s70_gpio_to_irq;
190	gchip->gc.label = dev_name(&pdev->dev);
191	gchip->gc.ngpio = 32;
192	gchip->gc.owner = THIS_MODULE;
193	gchip->gc.parent = &pdev->dev;
194	gchip->gc.base = -1;
195
196	ret = gpiochip_add_data(&gchip->gc, gchip);
197	if (ret) {
198		dev_err(&pdev->dev, "couldn't register gpio driver\n");
199		clk_disable_unprepare(gchip->clk);
200		return ret;
201	}
202
203	acpi_gpiochip_request_interrupts(&gchip->gc);
204
205	return 0;
206}
207
208static int mb86s70_gpio_remove(struct platform_device *pdev)
209{
210	struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev);
211
212	acpi_gpiochip_free_interrupts(&gchip->gc);
213	gpiochip_remove(&gchip->gc);
214	clk_disable_unprepare(gchip->clk);
215
216	return 0;
217}
218
219static const struct of_device_id mb86s70_gpio_dt_ids[] = {
220	{ .compatible = "fujitsu,mb86s70-gpio" },
221	{ /* sentinel */ }
222};
223MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
224
225#ifdef CONFIG_ACPI
226static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = {
227	{ "SCX0007" },
228	{ /* sentinel */ }
229};
230MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids);
231#endif
232
233static struct platform_driver mb86s70_gpio_driver = {
234	.driver = {
235		.name = "mb86s70-gpio",
236		.of_match_table = mb86s70_gpio_dt_ids,
237		.acpi_match_table = ACPI_PTR(mb86s70_gpio_acpi_ids),
238	},
239	.probe = mb86s70_gpio_probe,
240	.remove = mb86s70_gpio_remove,
241};
242module_platform_driver(mb86s70_gpio_driver);
243
244MODULE_DESCRIPTION("MB86S7x GPIO Driver");
245MODULE_ALIAS("platform:mb86s70-gpio");
246MODULE_LICENSE("GPL");