xref: /linux/drivers/gpio/gpio-mb86s7x.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
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 
35 struct mb86s70_gpio_chip {
36 	struct gpio_chip gc;
37 	void __iomem *base;
38 	struct clk *clk;
39 	spinlock_t lock;
40 };
41 
42 static 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 
59 static 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 
74 static 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 
91 static 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 
116 static 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 
123 static 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 
141 static 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 
157 static 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 
207 static 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 
216 static const struct of_device_id mb86s70_gpio_dt_ids[] = {
217 	{ .compatible = "fujitsu,mb86s70-gpio" },
218 	{ /* sentinel */ }
219 };
220 MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
221 
222 #ifdef CONFIG_ACPI
223 static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = {
224 	{ "SCX0007" },
225 	{ /* sentinel */ }
226 };
227 MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids);
228 #endif
229 
230 static 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 };
239 module_platform_driver(mb86s70_gpio_driver);
240 
241 MODULE_DESCRIPTION("MB86S7x GPIO Driver");
242 MODULE_ALIAS("platform:mb86s70-gpio");
243 MODULE_LICENSE("GPL");
244