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	struct clk *clk;
39	spinlock_t lock;
40};
41
42static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
43{
44	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
45	unsigned long flags;
46	u32 val;
47
48	spin_lock_irqsave(&gchip->lock, flags);
49
50	val = readl(gchip->base + PFR(gpio));
51	val &= ~OFFSET(gpio);
52	writel(val, gchip->base + PFR(gpio));
53
54	spin_unlock_irqrestore(&gchip->lock, flags);
55
56	return 0;
57}
58
59static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio)
60{
61	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
62	unsigned long flags;
63	u32 val;
64
65	spin_lock_irqsave(&gchip->lock, flags);
66
67	val = readl(gchip->base + PFR(gpio));
68	val |= OFFSET(gpio);
69	writel(val, gchip->base + PFR(gpio));
70
71	spin_unlock_irqrestore(&gchip->lock, flags);
72}
73
74static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
75{
76	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
77	unsigned long flags;
78	unsigned char val;
79
80	spin_lock_irqsave(&gchip->lock, flags);
81
82	val = readl(gchip->base + DDR(gpio));
83	val &= ~OFFSET(gpio);
84	writel(val, gchip->base + DDR(gpio));
85
86	spin_unlock_irqrestore(&gchip->lock, flags);
87
88	return 0;
89}
90
91static int mb86s70_gpio_direction_output(struct gpio_chip *gc,
92					 unsigned gpio, int value)
93{
94	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
95	unsigned long flags;
96	unsigned char val;
97
98	spin_lock_irqsave(&gchip->lock, flags);
99
100	val = readl(gchip->base + PDR(gpio));
101	if (value)
102		val |= OFFSET(gpio);
103	else
104		val &= ~OFFSET(gpio);
105	writel(val, gchip->base + PDR(gpio));
106
107	val = readl(gchip->base + DDR(gpio));
108	val |= OFFSET(gpio);
109	writel(val, gchip->base + DDR(gpio));
110
111	spin_unlock_irqrestore(&gchip->lock, flags);
112
113	return 0;
114}
115
116static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio)
117{
118	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
119
120	return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio));
121}
122
123static void mb86s70_gpio_set(struct gpio_chip *gc, unsigned gpio, int value)
124{
125	struct mb86s70_gpio_chip *gchip = gpiochip_get_data(gc);
126	unsigned long flags;
127	unsigned char val;
128
129	spin_lock_irqsave(&gchip->lock, flags);
130
131	val = readl(gchip->base + PDR(gpio));
132	if (value)
133		val |= OFFSET(gpio);
134	else
135		val &= ~OFFSET(gpio);
136	writel(val, gchip->base + PDR(gpio));
137
138	spin_unlock_irqrestore(&gchip->lock, flags);
139}
140
141static int mb86s70_gpio_to_irq(struct gpio_chip *gc, unsigned int offset)
142{
143	int irq, index;
144
145	for (index = 0;; index++) {
146		irq = platform_get_irq(to_platform_device(gc->parent), index);
147		if (irq < 0)
148			return irq;
149		if (irq == 0)
150			break;
151		if (irq_get_irq_data(irq)->hwirq == offset)
152			return irq;
153	}
154	return -EINVAL;
155}
156
157static int mb86s70_gpio_probe(struct platform_device *pdev)
158{
159	struct mb86s70_gpio_chip *gchip;
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	gchip->clk = devm_clk_get_optional(&pdev->dev, NULL);
173	if (IS_ERR(gchip->clk))
174		return PTR_ERR(gchip->clk);
175
176	ret = clk_prepare_enable(gchip->clk);
177	if (ret)
178		return ret;
179
180	spin_lock_init(&gchip->lock);
181
182	gchip->gc.direction_output = mb86s70_gpio_direction_output;
183	gchip->gc.direction_input = mb86s70_gpio_direction_input;
184	gchip->gc.request = mb86s70_gpio_request;
185	gchip->gc.free = mb86s70_gpio_free;
186	gchip->gc.get = mb86s70_gpio_get;
187	gchip->gc.set = mb86s70_gpio_set;
188	gchip->gc.to_irq = mb86s70_gpio_to_irq;
189	gchip->gc.label = dev_name(&pdev->dev);
190	gchip->gc.ngpio = 32;
191	gchip->gc.owner = THIS_MODULE;
192	gchip->gc.parent = &pdev->dev;
193	gchip->gc.base = -1;
194
195	ret = gpiochip_add_data(&gchip->gc, gchip);
196	if (ret) {
197		dev_err(&pdev->dev, "couldn't register gpio driver\n");
198		clk_disable_unprepare(gchip->clk);
199		return ret;
200	}
201
202	acpi_gpiochip_request_interrupts(&gchip->gc);
203
204	return 0;
205}
206
207static void mb86s70_gpio_remove(struct platform_device *pdev)
208{
209	struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev);
210
211	acpi_gpiochip_free_interrupts(&gchip->gc);
212	gpiochip_remove(&gchip->gc);
213	clk_disable_unprepare(gchip->clk);
214}
215
216static const struct of_device_id mb86s70_gpio_dt_ids[] = {
217	{ .compatible = "fujitsu,mb86s70-gpio" },
218	{ /* sentinel */ }
219};
220MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
221
222#ifdef CONFIG_ACPI
223static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = {
224	{ "SCX0007" },
225	{ /* sentinel */ }
226};
227MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids);
228#endif
229
230static struct platform_driver mb86s70_gpio_driver = {
231	.driver = {
232		.name = "mb86s70-gpio",
233		.of_match_table = mb86s70_gpio_dt_ids,
234		.acpi_match_table = ACPI_PTR(mb86s70_gpio_acpi_ids),
235	},
236	.probe = mb86s70_gpio_probe,
237	.remove_new = mb86s70_gpio_remove,
238};
239module_platform_driver(mb86s70_gpio_driver);
240
241MODULE_DESCRIPTION("MB86S7x GPIO Driver");
242MODULE_ALIAS("platform:mb86s70-gpio");
243MODULE_LICENSE("GPL");
244