2 * linux/drivers/gpio/gpio-mb86s7x.c
4 * Copyright (C) 2015 Fujitsu Semiconductor Limited
5 * Copyright (C) 2015 Linaro Ltd.
7 * This program is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, version 2 of the License.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
18 #include <linux/init.h>
19 #include <linux/clk.h>
20 #include <linux/module.h>
21 #include <linux/err.h>
22 #include <linux/errno.h>
23 #include <linux/ioport.h>
24 #include <linux/of_device.h>
25 #include <linux/gpio/driver.h>
26 #include <linux/platform_device.h>
27 #include <linux/spinlock.h>
28 #include <linux/slab.h>
31 * Only first 8bits of a register correspond to each pin,
32 * so there are 4 registers for 32 pins.
34 #define PDR(x) (0x0 + x / 8 * 4)
35 #define DDR(x) (0x10 + x / 8 * 4)
36 #define PFR(x) (0x20 + x / 8 * 4)
38 #define OFFSET(x) BIT((x) % 8)
40 struct mb86s70_gpio_chip {
47 static inline struct mb86s70_gpio_chip *chip_to_mb86s70(struct gpio_chip *gc)
49 return container_of(gc, struct mb86s70_gpio_chip, gc);
52 static int mb86s70_gpio_request(struct gpio_chip *gc, unsigned gpio)
54 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
58 spin_lock_irqsave(&gchip->lock, flags);
60 val = readl(gchip->base + PFR(gpio));
62 writel(val, gchip->base + PFR(gpio));
64 spin_unlock_irqrestore(&gchip->lock, flags);
69 static void mb86s70_gpio_free(struct gpio_chip *gc, unsigned gpio)
71 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
75 spin_lock_irqsave(&gchip->lock, flags);
77 val = readl(gchip->base + PFR(gpio));
79 writel(val, gchip->base + PFR(gpio));
81 spin_unlock_irqrestore(&gchip->lock, flags);
84 static int mb86s70_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
86 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
90 spin_lock_irqsave(&gchip->lock, flags);
92 val = readl(gchip->base + DDR(gpio));
94 writel(val, gchip->base + DDR(gpio));
96 spin_unlock_irqrestore(&gchip->lock, flags);
101 static int mb86s70_gpio_direction_output(struct gpio_chip *gc,
102 unsigned gpio, int value)
104 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
108 spin_lock_irqsave(&gchip->lock, flags);
110 val = readl(gchip->base + PDR(gpio));
114 val &= ~OFFSET(gpio);
115 writel(val, gchip->base + PDR(gpio));
117 val = readl(gchip->base + DDR(gpio));
119 writel(val, gchip->base + DDR(gpio));
121 spin_unlock_irqrestore(&gchip->lock, flags);
126 static int mb86s70_gpio_get(struct gpio_chip *gc, unsigned gpio)
128 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
130 return !!(readl(gchip->base + PDR(gpio)) & OFFSET(gpio));
133 static void mb86s70_gpio_set(struct gpio_chip *gc, unsigned gpio, int value)
135 struct mb86s70_gpio_chip *gchip = chip_to_mb86s70(gc);
139 spin_lock_irqsave(&gchip->lock, flags);
141 val = readl(gchip->base + PDR(gpio));
145 val &= ~OFFSET(gpio);
146 writel(val, gchip->base + PDR(gpio));
148 spin_unlock_irqrestore(&gchip->lock, flags);
151 static int mb86s70_gpio_probe(struct platform_device *pdev)
153 struct mb86s70_gpio_chip *gchip;
154 struct resource *res;
157 gchip = devm_kzalloc(&pdev->dev, sizeof(*gchip), GFP_KERNEL);
161 platform_set_drvdata(pdev, gchip);
163 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
164 gchip->base = devm_ioremap_resource(&pdev->dev, res);
165 if (IS_ERR(gchip->base))
166 return PTR_ERR(gchip->base);
168 gchip->clk = devm_clk_get(&pdev->dev, NULL);
169 if (IS_ERR(gchip->clk))
170 return PTR_ERR(gchip->clk);
172 clk_prepare_enable(gchip->clk);
174 spin_lock_init(&gchip->lock);
176 gchip->gc.direction_output = mb86s70_gpio_direction_output;
177 gchip->gc.direction_input = mb86s70_gpio_direction_input;
178 gchip->gc.request = mb86s70_gpio_request;
179 gchip->gc.free = mb86s70_gpio_free;
180 gchip->gc.get = mb86s70_gpio_get;
181 gchip->gc.set = mb86s70_gpio_set;
182 gchip->gc.label = dev_name(&pdev->dev);
183 gchip->gc.ngpio = 32;
184 gchip->gc.owner = THIS_MODULE;
185 gchip->gc.dev = &pdev->dev;
188 platform_set_drvdata(pdev, gchip);
190 ret = gpiochip_add(&gchip->gc);
192 dev_err(&pdev->dev, "couldn't register gpio driver\n");
193 clk_disable_unprepare(gchip->clk);
199 static int mb86s70_gpio_remove(struct platform_device *pdev)
201 struct mb86s70_gpio_chip *gchip = platform_get_drvdata(pdev);
203 gpiochip_remove(&gchip->gc);
204 clk_disable_unprepare(gchip->clk);
209 static const struct of_device_id mb86s70_gpio_dt_ids[] = {
210 { .compatible = "fujitsu,mb86s70-gpio" },
213 MODULE_DEVICE_TABLE(of, mb86s70_gpio_dt_ids);
215 static struct platform_driver mb86s70_gpio_driver = {
217 .name = "mb86s70-gpio",
218 .of_match_table = mb86s70_gpio_dt_ids,
220 .probe = mb86s70_gpio_probe,
221 .remove = mb86s70_gpio_remove,
224 static int __init mb86s70_gpio_init(void)
226 return platform_driver_register(&mb86s70_gpio_driver);
228 module_init(mb86s70_gpio_init);
230 MODULE_DESCRIPTION("MB86S7x GPIO Driver");
231 MODULE_ALIAS("platform:mb86s70-gpio");
232 MODULE_LICENSE("GPL");