1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-loongson1.c b/drivers/gpio/gpio-loongson1.c
new file mode 100644
index 0000000000..6ca3b969db
--- /dev/null
+++ b/drivers/gpio/gpio-loongson1.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GPIO Driver for Loongson 1 SoC
+ *
+ * Copyright (C) 2015-2023 Keguang Zhang <keguang.zhang@gmail.com>
+ */
+
+#include <linux/module.h>
+#include <linux/gpio/driver.h>
+#include <linux/platform_device.h>
+#include <linux/bitops.h>
+
+/* Loongson 1 GPIO Register Definitions */
+#define GPIO_CFG		0x0
+#define GPIO_DIR		0x10
+#define GPIO_DATA		0x20
+#define GPIO_OUTPUT		0x30
+
+struct ls1x_gpio_chip {
+	struct gpio_chip gc;
+	void __iomem *reg_base;
+};
+
+static int ls1x_gpio_request(struct gpio_chip *gc, unsigned int offset)
+{
+	struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
+	__raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) | BIT(offset),
+		     ls1x_gc->reg_base + GPIO_CFG);
+	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+
+	return 0;
+}
+
+static void ls1x_gpio_free(struct gpio_chip *gc, unsigned int offset)
+{
+	struct ls1x_gpio_chip *ls1x_gc = gpiochip_get_data(gc);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
+	__raw_writel(__raw_readl(ls1x_gc->reg_base + GPIO_CFG) & ~BIT(offset),
+		     ls1x_gc->reg_base + GPIO_CFG);
+	raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+}
+
+static int ls1x_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ls1x_gpio_chip *ls1x_gc;
+	int ret;
+
+	ls1x_gc = devm_kzalloc(dev, sizeof(*ls1x_gc), GFP_KERNEL);
+	if (!ls1x_gc)
+		return -ENOMEM;
+
+	ls1x_gc->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ls1x_gc->reg_base))
+		return PTR_ERR(ls1x_gc->reg_base);
+
+	ret = bgpio_init(&ls1x_gc->gc, dev, 4, ls1x_gc->reg_base + GPIO_DATA,
+			 ls1x_gc->reg_base + GPIO_OUTPUT, NULL,
+			 NULL, ls1x_gc->reg_base + GPIO_DIR, 0);
+	if (ret)
+		goto err;
+
+	ls1x_gc->gc.owner = THIS_MODULE;
+	ls1x_gc->gc.request = ls1x_gpio_request;
+	ls1x_gc->gc.free = ls1x_gpio_free;
+	/*
+	 * Clear ngpio to let gpiolib get the correct number
+	 * by reading ngpios property
+	 */
+	ls1x_gc->gc.ngpio = 0;
+
+	ret = devm_gpiochip_add_data(dev, &ls1x_gc->gc, ls1x_gc);
+	if (ret)
+		goto err;
+
+	platform_set_drvdata(pdev, ls1x_gc);
+
+	dev_info(dev, "GPIO controller registered with %d pins\n",
+		 ls1x_gc->gc.ngpio);
+
+	return 0;
+err:
+	dev_err(dev, "failed to register GPIO controller\n");
+	return ret;
+}
+
+static const struct of_device_id ls1x_gpio_dt_ids[] = {
+	{ .compatible = "loongson,ls1x-gpio" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ls1x_gpio_dt_ids);
+
+static struct platform_driver ls1x_gpio_driver = {
+	.probe	= ls1x_gpio_probe,
+	.driver	= {
+		.name	= "ls1x-gpio",
+		.of_match_table = ls1x_gpio_dt_ids,
+	},
+};
+
+module_platform_driver(ls1x_gpio_driver);
+
+MODULE_AUTHOR("Keguang Zhang <keguang.zhang@gmail.com>");
+MODULE_DESCRIPTION("Loongson1 GPIO driver");
+MODULE_LICENSE("GPL");