From 673d3358b0b9ba9e75de4d4775cbfd33b9d93552 Mon Sep 17 00:00:00 2001
From: Wyon Bi <bivvy.bi@rock-chips.com>
Date: Mon, 2 May 2022 02:13:26 +0000
Subject: [PATCH] gpio: Add support for Maxim MAX96752F GPIO controller

Signed-off-by: Wyon Bi <bivvy.bi@rock-chips.com>
Change-Id: Ib94de1c8ac1af44f0f3b61aa5eccff8dda741450
---
 drivers/gpio/Kconfig          |   7 +++
 drivers/gpio/Makefile         |   1 +
 drivers/gpio/gpio-max96752f.c | 104 ++++++++++++++++++++++++++++++++++
 3 files changed, 112 insertions(+)
 create mode 100644 drivers/gpio/gpio-max96752f.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 9a4110ad1c20..d82126d6135d 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1235,6 +1235,13 @@ config GPIO_MAX77650
 	  GPIO driver for MAX77650/77651 PMIC from Maxim Semiconductor.
 	  These chips have a single pin that can be configured as GPIO.
 
+config GPIO_MAX96752F
+	tristate "MAX96752F GPIO"
+	depends on MFD_MAX96752F
+	help
+	  Select this option to enable GPIO driver for the MAX96752F
+	  chip.
+
 config GPIO_MSIC
 	bool "Intel MSIC mixed signal gpio support"
 	depends on (X86 || COMPILE_TEST) && MFD_INTEL_MSIC
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index ce6cafb6d3de..7b42304be907 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_GPIO_MAX730X)		+= gpio-max730x.o
 obj-$(CONFIG_GPIO_MAX732X)		+= gpio-max732x.o
 obj-$(CONFIG_GPIO_MAX77620)		+= gpio-max77620.o
 obj-$(CONFIG_GPIO_MAX77650)		+= gpio-max77650.o
+obj-$(CONFIG_GPIO_MAX96752F)		+= gpio-max96752f.o
 obj-$(CONFIG_GPIO_MB86S7X)		+= gpio-mb86s7x.o
 obj-$(CONFIG_GPIO_MC33880)		+= gpio-mc33880.o
 obj-$(CONFIG_GPIO_MC9S08DZ60)		+= gpio-mc9s08dz60.o
diff --git a/drivers/gpio/gpio-max96752f.c b/drivers/gpio/gpio-max96752f.c
new file mode 100644
index 000000000000..1c3816737c55
--- /dev/null
+++ b/drivers/gpio/gpio-max96752f.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Maxim MAX96752F GPIO driver
+ *
+ * Copyright (C) 2022 Rockchip Electronics Co. Ltd.
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/max96752f.h>
+
+struct max96752f_gpio {
+	struct device *dev;
+	struct regmap *regmap;
+	struct gpio_chip gpio_chip;
+};
+
+static int max96752f_gpio_direction_output(struct gpio_chip *gc,
+					   unsigned int offset, int value)
+{
+	struct max96752f_gpio *gpio = gpiochip_get_data(gc);
+
+	regmap_update_bits(gpio->regmap, GPIO_A_REG(offset),
+			   GPIO_OUT_DIS | GPIO_OUT,
+			   FIELD_PREP(GPIO_OUT_DIS, 0) |
+			   FIELD_PREP(GPIO_OUT, value));
+
+	return 0;
+}
+
+static void max96752f_gpio_set(struct gpio_chip *gc, unsigned int offset,
+			       int value)
+{
+	struct max96752f_gpio *gpio = gpiochip_get_data(gc);
+
+	regmap_update_bits(gpio->regmap, GPIO_A_REG(offset), GPIO_OUT,
+			   FIELD_PREP(GPIO_OUT, value));
+}
+
+static int max96752f_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+	struct max96752f_gpio *gpio = gpiochip_get_data(gc);
+	unsigned int value;
+
+	regmap_read(gpio->regmap, GPIO_A_REG(offset), &value);
+
+	return !!FIELD_GET(GPIO_OUT, value);
+}
+
+static int max96752f_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct max96752f_gpio *gpio;
+	int ret;
+
+	gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
+	if (!gpio)
+		return -ENOMEM;
+
+	gpio->dev = dev;
+	platform_set_drvdata(pdev, gpio);
+
+	gpio->regmap = dev_get_regmap(dev->parent, NULL);
+	if (!gpio->regmap)
+		return dev_err_probe(dev, -ENODEV, "failed to get regmap\n");
+
+	gpio->gpio_chip.of_node = dev->of_node;
+	gpio->gpio_chip.label = dev_name(dev);
+	gpio->gpio_chip.parent = dev->parent;
+	gpio->gpio_chip.direction_output = max96752f_gpio_direction_output;
+	gpio->gpio_chip.set = max96752f_gpio_set;
+	gpio->gpio_chip.get = max96752f_gpio_get;
+	gpio->gpio_chip.ngpio = 16;
+	gpio->gpio_chip.can_sleep = true;
+	gpio->gpio_chip.base = -1;
+
+	ret = devm_gpiochip_add_data(dev, &gpio->gpio_chip, gpio);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to add gpio chip\n");
+
+	return 0;
+}
+
+static const struct of_device_id max96752f_gpio_of_match[] = {
+	{ .name = "maxim,max96752f-gpio", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, max96752f_gpio_of_match);
+
+static struct platform_driver max96752f_gpio_driver = {
+	.driver = {
+		.name	= "max96752f-gpio",
+		.of_match_table = max96752f_gpio_of_match,
+	},
+	.probe = max96752f_gpio_probe,
+};
+
+module_platform_driver(max96752f_gpio_driver);
+
+MODULE_AUTHOR("Wyon Bi <bivvy.bi@rock-chips.com>");
+MODULE_DESCRIPTION("Maxim MAX96752F GPIO driver");
+MODULE_LICENSE("GPL");