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
36 struct mb86s70_gpio_chip {
37 struct gpio_chip gc;
38 void __iomem *base;
39 struct clk *clk;
40 spinlock_t lock;
41 };
42
mb86s70_gpio_request(struct gpio_chip * gc,unsigned gpio)43 static 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
mb86s70_gpio_free(struct gpio_chip * gc,unsigned gpio)60 static 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
mb86s70_gpio_direction_input(struct gpio_chip * gc,unsigned gpio)75 static 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
mb86s70_gpio_direction_output(struct gpio_chip * gc,unsigned gpio,int value)92 static 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
mb86s70_gpio_get(struct gpio_chip * gc,unsigned gpio)117 static 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
mb86s70_gpio_set(struct gpio_chip * gc,unsigned gpio,int value)124 static 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
mb86s70_gpio_to_irq(struct gpio_chip * gc,unsigned int offset)142 static 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
mb86s70_gpio_probe(struct platform_device * pdev)158 static 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
mb86s70_gpio_remove(struct platform_device * pdev)208 static 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
219 static const struct of_device_id mb86s70_gpio_dt_ids[] = {
220 { .compatible = "fujitsu,mb86s70-gpio" },
221 { /* sentinel */ }
222 };
223 MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
224
225 #ifdef CONFIG_ACPI
226 static const struct acpi_device_id mb86s70_gpio_acpi_ids[] = {
227 { "SCX0007" },
228 { /* sentinel */ }
229 };
230 MODULE_DEVICE_TABLE(acpi, mb86s70_gpio_acpi_ids);
231 #endif
232
233 static 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 };
242 module_platform_driver(mb86s70_gpio_driver);
243
244 MODULE_DESCRIPTION("MB86S7x GPIO Driver");
245 MODULE_ALIAS("platform:mb86s70-gpio");
246 MODULE_LICENSE("GPL");
247
