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path: root/drivers/gpio/gpio-amd-fch.c
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Diffstat (limited to 'drivers/gpio/gpio-amd-fch.c')
-rw-r--r--drivers/gpio/gpio-amd-fch.c192
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-amd-fch.c b/drivers/gpio/gpio-amd-fch.c
new file mode 100644
index 000000000..2a21354ed
--- /dev/null
+++ b/drivers/gpio/gpio-amd-fch.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+/*
+ * GPIO driver for the AMD G series FCH (eg. GX-412TC)
+ *
+ * Copyright (C) 2018 metux IT consult
+ * Author: Enrico Weigelt, metux IT consult <info@metux.net>
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/gpio/driver.h>
+#include <linux/platform_data/gpio/gpio-amd-fch.h>
+#include <linux/spinlock.h>
+
+#define AMD_FCH_MMIO_BASE 0xFED80000
+#define AMD_FCH_GPIO_BANK0_BASE 0x1500
+#define AMD_FCH_GPIO_SIZE 0x0300
+
+#define AMD_FCH_GPIO_FLAG_DIRECTION BIT(23)
+#define AMD_FCH_GPIO_FLAG_WRITE BIT(22)
+#define AMD_FCH_GPIO_FLAG_READ BIT(16)
+
+static const struct resource amd_fch_gpio_iores =
+ DEFINE_RES_MEM_NAMED(
+ AMD_FCH_MMIO_BASE + AMD_FCH_GPIO_BANK0_BASE,
+ AMD_FCH_GPIO_SIZE,
+ "amd-fch-gpio-iomem");
+
+struct amd_fch_gpio_priv {
+ struct gpio_chip gc;
+ void __iomem *base;
+ struct amd_fch_gpio_pdata *pdata;
+ spinlock_t lock;
+};
+
+static void __iomem *amd_fch_gpio_addr(struct amd_fch_gpio_priv *priv,
+ unsigned int gpio)
+{
+ return priv->base + priv->pdata->gpio_reg[gpio]*sizeof(u32);
+}
+
+static int amd_fch_gpio_direction_input(struct gpio_chip *gc,
+ unsigned int offset)
+{
+ unsigned long flags;
+ struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
+ void __iomem *ptr = amd_fch_gpio_addr(priv, offset);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ writel_relaxed(readl_relaxed(ptr) & ~AMD_FCH_GPIO_FLAG_DIRECTION, ptr);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int amd_fch_gpio_direction_output(struct gpio_chip *gc,
+ unsigned int gpio, int value)
+{
+ unsigned long flags;
+ struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
+ void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
+ u32 val;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ val = readl_relaxed(ptr);
+ if (value)
+ val |= AMD_FCH_GPIO_FLAG_WRITE;
+ else
+ val &= ~AMD_FCH_GPIO_FLAG_WRITE;
+
+ writel_relaxed(val | AMD_FCH_GPIO_FLAG_DIRECTION, ptr);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int amd_fch_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio)
+{
+ int ret;
+ unsigned long flags;
+ struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
+ void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ ret = (readl_relaxed(ptr) & AMD_FCH_GPIO_FLAG_DIRECTION);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
+static void amd_fch_gpio_set(struct gpio_chip *gc,
+ unsigned int gpio, int value)
+{
+ unsigned long flags;
+ struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
+ void __iomem *ptr = amd_fch_gpio_addr(priv, gpio);
+ u32 mask;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ mask = readl_relaxed(ptr);
+ if (value)
+ mask |= AMD_FCH_GPIO_FLAG_WRITE;
+ else
+ mask &= ~AMD_FCH_GPIO_FLAG_WRITE;
+ writel_relaxed(mask, ptr);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static int amd_fch_gpio_get(struct gpio_chip *gc,
+ unsigned int offset)
+{
+ unsigned long flags;
+ int ret;
+ struct amd_fch_gpio_priv *priv = gpiochip_get_data(gc);
+ void __iomem *ptr = amd_fch_gpio_addr(priv, offset);
+
+ spin_lock_irqsave(&priv->lock, flags);
+ ret = (readl_relaxed(ptr) & AMD_FCH_GPIO_FLAG_READ);
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return ret;
+}
+
+static int amd_fch_gpio_request(struct gpio_chip *chip,
+ unsigned int gpio_pin)
+{
+ return 0;
+}
+
+static int amd_fch_gpio_probe(struct platform_device *pdev)
+{
+ struct amd_fch_gpio_priv *priv;
+ struct amd_fch_gpio_pdata *pdata;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!pdata) {
+ dev_err(&pdev->dev, "no platform_data\n");
+ return -ENOENT;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->pdata = pdata;
+
+ priv->gc.owner = THIS_MODULE;
+ priv->gc.parent = &pdev->dev;
+ priv->gc.label = dev_name(&pdev->dev);
+ priv->gc.ngpio = priv->pdata->gpio_num;
+ priv->gc.names = priv->pdata->gpio_names;
+ priv->gc.base = -1;
+ priv->gc.request = amd_fch_gpio_request;
+ priv->gc.direction_input = amd_fch_gpio_direction_input;
+ priv->gc.direction_output = amd_fch_gpio_direction_output;
+ priv->gc.get_direction = amd_fch_gpio_get_direction;
+ priv->gc.get = amd_fch_gpio_get;
+ priv->gc.set = amd_fch_gpio_set;
+
+ spin_lock_init(&priv->lock);
+
+ priv->base = devm_ioremap_resource(&pdev->dev, &amd_fch_gpio_iores);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ platform_set_drvdata(pdev, priv);
+
+ return devm_gpiochip_add_data(&pdev->dev, &priv->gc, priv);
+}
+
+static struct platform_driver amd_fch_gpio_driver = {
+ .driver = {
+ .name = AMD_FCH_GPIO_DRIVER_NAME,
+ },
+ .probe = amd_fch_gpio_probe,
+};
+
+module_platform_driver(amd_fch_gpio_driver);
+
+MODULE_AUTHOR("Enrico Weigelt, metux IT consult <info@metux.net>");
+MODULE_DESCRIPTION("AMD G-series FCH GPIO driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" AMD_FCH_GPIO_DRIVER_NAME);