1 // SPDX-License-Identifier: GPL-2.0+
4 * GPIO driver for the AMD G series FCH (eg. GX-412TC)
6 * Copyright (C) 2018 metux IT consult
7 * Author: Enrico Weigelt, metux IT consult <info@metux.net>
11 #include <linux/err.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/gpio/driver.h>
17 #include <linux/platform_data/gpio/gpio-amd-fch.h>
18 #include <linux/spinlock.h>
20 #define AMD_FCH_MMIO_BASE 0xFED80000
21 #define AMD_FCH_GPIO_BANK0_BASE 0x1500
22 #define AMD_FCH_GPIO_SIZE 0x0300
24 #define AMD_FCH_GPIO_FLAG_DIRECTION BIT(23)
25 #define AMD_FCH_GPIO_FLAG_WRITE BIT(22)
26 #define AMD_FCH_GPIO_FLAG_READ BIT(16)
28 static struct resource amd_fch_gpio_iores =
30 AMD_FCH_MMIO_BASE + AMD_FCH_GPIO_BANK0_BASE,
32 "amd-fch-gpio-iomem");
34 struct amd_fch_gpio_priv {
35 struct platform_device *pdev;
38 struct amd_fch_gpio_pdata *pdata;
42 static void __iomem *amd_fch_gpio_addr(struct amd_fch_gpio_priv *priv,
45 return priv->base + priv->pdata->gpio_reg[gpio]*sizeof(u32);
48 static int amd_fch_gpio_direction_input(struct gpio_chip *gc,
52 struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
53 void __iomem *ptr = amd_fch_gpio_addr(priv, offset);
55 spin_lock_irqsave(&priv->lock, flags);
56 writel_relaxed(readl_relaxed(ptr) & ~AMD_FCH_GPIO_FLAG_DIRECTION, ptr);
57 spin_unlock_irqrestore(&priv->lock, flags);
62 static int amd_fch_gpio_direction_output(struct gpio_chip *gc,
63 unsigned int gpio, int value)
66 struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
67 void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
69 spin_lock_irqsave(&priv->lock, flags);
70 writel_relaxed(readl_relaxed(ptr) | AMD_FCH_GPIO_FLAG_DIRECTION, ptr);
71 spin_unlock_irqrestore(&priv->lock, flags);
76 static int amd_fch_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio)
80 struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
81 void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
83 spin_lock_irqsave(&priv->lock, flags);
84 ret = (readl_relaxed(ptr) & AMD_FCH_GPIO_FLAG_DIRECTION);
85 spin_unlock_irqrestore(&priv->lock, flags);
90 static void amd_fch_gpio_set(struct gpio_chip *gc,
91 unsigned int gpio, int value)
94 struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
95 void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
98 spin_lock_irqsave(&priv->lock, flags);
100 mask = readl_relaxed(ptr);
102 mask |= AMD_FCH_GPIO_FLAG_WRITE;
104 mask &= ~AMD_FCH_GPIO_FLAG_WRITE;
105 writel_relaxed(mask, ptr);
107 spin_unlock_irqrestore(&priv->lock, flags);
110 static int amd_fch_gpio_get(struct gpio_chip *gc,
115 struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
116 void __iomem *ptr = amd_fch_gpio_addr(priv, offset);
118 spin_lock_irqsave(&priv->lock, flags);
119 ret = (readl_relaxed(ptr) & AMD_FCH_GPIO_FLAG_READ);
120 spin_unlock_irqrestore(&priv->lock, flags);
125 static int amd_fch_gpio_request(struct gpio_chip *chip,
126 unsigned int gpio_pin)
131 static int amd_fch_gpio_probe(struct platform_device *pdev)
133 struct amd_fch_gpio_priv *priv;
134 struct amd_fch_gpio_pdata *pdata;
136 pdata = dev_get_platdata(&pdev->dev);
138 dev_err(&pdev->dev, "no platform_data\n");
142 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
149 priv->gc.owner = THIS_MODULE;
150 priv->gc.parent = &pdev->dev;
151 priv->gc.label = dev_name(&pdev->dev);
152 priv->gc.ngpio = priv->pdata->gpio_num;
153 priv->gc.names = priv->pdata->gpio_names;
155 priv->gc.request = amd_fch_gpio_request;
156 priv->gc.direction_input = amd_fch_gpio_direction_input;
157 priv->gc.direction_output = amd_fch_gpio_direction_output;
158 priv->gc.get_direction = amd_fch_gpio_get_direction;
159 priv->gc.get = amd_fch_gpio_get;
160 priv->gc.set = amd_fch_gpio_set;
162 spin_lock_init(&priv->lock);
164 priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
165 if (IS_ERR(priv->base))
166 return PTR_ERR(priv->base);
168 platform_set_drvdata(pdev, priv);
170 return devm_gpiochip_add_data(&pdev->dev, &priv->gc, priv);
173 static struct platform_driver amd_fch_gpio_driver = {
175 .name = AMD_FCH_GPIO_DRIVER_NAME,
177 .probe = amd_fch_gpio_probe,
180 module_platform_driver(amd_fch_gpio_driver);
182 MODULE_AUTHOR("Enrico Weigelt, metux IT consult <info@metux.net>");
183 MODULE_DESCRIPTION("AMD G-series FCH GPIO driver");
184 MODULE_LICENSE("GPL");
185 MODULE_ALIAS("platform:" AMD_FCH_GPIO_DRIVER_NAME);