1 files changed, 139 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-imx-scu.c b/drivers/gpio/gpio-imx-scu.c
new file mode 100644
index 000000000000..17be21b8f3b7
--- /dev/null
+++ b/drivers/gpio/gpio-imx-scu.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2021~2022 NXP
+ *
+ * The driver exports a standard gpiochip interface
+ * to control the PIN resources on SCU domain.
+ */
+
+#include <linux/module.h>
+#include <linux/gpio/driver.h>
+#include <linux/platform_device.h>
+#include <linux/firmware/imx/svc/rm.h>
+#include <dt-bindings/firmware/imx/rsrc.h>
+
+struct scu_gpio_priv {
+	struct gpio_chip	chip;
+	struct mutex		lock;
+	struct device		*dev;
+	struct imx_sc_ipc	*handle;
+};
+
+static unsigned int scu_rsrc_arr[] = {
+	IMX_SC_R_BOARD_R0,
+	IMX_SC_R_BOARD_R1,
+	IMX_SC_R_BOARD_R2,
+	IMX_SC_R_BOARD_R3,
+	IMX_SC_R_BOARD_R4,
+	IMX_SC_R_BOARD_R5,
+	IMX_SC_R_BOARD_R6,
+	IMX_SC_R_BOARD_R7,
+};
+
+static int imx_scu_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct scu_gpio_priv *priv = gpiochip_get_data(chip);
+	int level;
+	int err;
+
+	if (offset >= chip->ngpio)
+		return -EINVAL;
+
+	mutex_lock(&priv->lock);
+
+	/* to read PIN state via scu api */
+	err = imx_sc_misc_get_control(priv->handle,
+			scu_rsrc_arr[offset], 0, &level);
+	mutex_unlock(&priv->lock);
+
+	if (err) {
+		dev_err(priv->dev, "SCU get failed: %d\n", err);
+		return err;
+	}
+
+	return level;
+}
+
+static void imx_scu_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	struct scu_gpio_priv *priv = gpiochip_get_data(chip);
+	int err;
+
+	if (offset >= chip->ngpio)
+		return;
+
+	mutex_lock(&priv->lock);
+
+	/* to set PIN output level via scu api */
+	err = imx_sc_misc_set_control(priv->handle,
+			scu_rsrc_arr[offset], 0, value);
+	mutex_unlock(&priv->lock);
+
+	if (err)
+		dev_err(priv->dev, "SCU set (%d) failed: %d\n",
+				scu_rsrc_arr[offset], err);
+}
+
+static int imx_scu_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+	if (offset >= chip->ngpio)
+		return -EINVAL;
+
+	return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int imx_scu_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct scu_gpio_priv *priv;
+	struct gpio_chip *gc;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	ret = imx_scu_get_handle(&priv->handle);
+	if (ret)
+		return ret;
+
+	priv->dev = dev;
+	mutex_init(&priv->lock);
+
+	gc = &priv->chip;
+	gc->base = -1;
+	gc->parent = dev;
+	gc->ngpio = sizeof(scu_rsrc_arr)/sizeof(unsigned int);
+	gc->label = dev_name(dev);
+	gc->get = imx_scu_gpio_get;
+	gc->set = imx_scu_gpio_set;
+	gc->get_direction = imx_scu_gpio_get_direction;
+
+	platform_set_drvdata(pdev, priv);
+
+	return devm_gpiochip_add_data(dev, gc, priv);
+}
+
+static const struct of_device_id imx_scu_gpio_dt_ids[] = {
+	{ .compatible = "fsl,imx8qxp-sc-gpio" },
+	{ /* sentinel */ }
+};
+
+static struct platform_driver imx_scu_gpio_driver = {
+	.driver	= {
+		.name = "gpio-imx-scu",
+		.of_match_table = imx_scu_gpio_dt_ids,
+	},
+	.probe = imx_scu_gpio_probe,
+};
+
+static int __init _imx_scu_gpio_init(void)
+{
+	return platform_driver_register(&imx_scu_gpio_driver);
+}
+
+subsys_initcall_sync(_imx_scu_gpio_init);
+
+MODULE_AUTHOR("Shenwei Wang <shenwei.wang@nxp.com>");
+MODULE_DESCRIPTION("NXP GPIO over IMX SCU API");
+MODULE_LICENSE("GPL");