gpio: porting gpiolib function [1/1]

PD#SWPL-65870

Problem:
add function gpiod_set_pull

Solution:
add function gpiod_set_pull

Verify:
s4d

Signed-off-by: wanwei.jiang <wanwei.jiang@amlogic.com>
Change-Id: Id027b5b1abfb675445ff01fc8faaa207147a8954

arch/arm64/configs/amlogic_gki.fragment

@@ -47,3 +47,6 @@ CONFIG_AMLOGIC_CPU_INFO=m
 # amlogic-pm.ko
 CONFIG_AMLOGIC_GX_SUSPEND=m
 CONFIG_AMLOGIC_LEGACY_EARLY_SUSPEND=y
+
+# amlogic-gpiolib.ko
+CONFIG_AMLOGIC_GPIOLIB=m

drivers/Kconfig

@@ -10,4 +10,6 @@ source "../common_drivers/drivers/secmon/Kconfig"
 source "../common_drivers/drivers/power/Kconfig"
 source "../common_drivers/drivers/cpu_info/Kconfig"
 source "../common_drivers/drivers/pm/Kconfig"
+source "../common_drivers/drivers/gpio/Kconfig"
+
 endmenu

drivers/Makefile

@@ -8,6 +8,7 @@ obj-y		+= secmon/
 obj-y		+= power/
 obj-y		+= cpu_info/
 obj-y		+= pm/
+obj-y		+= gpio/
 
 KBUILD_CFLAGS_MODULE += $(GKI_EXT_MODULE_PREDEFINE)
 

drivers/gpio/Kconfig

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+config AMLOGIC_GPIOLIB
+        tristate "Amlogic gpiolib expand"
+	depends on GPIOLIB
+	default n
+        help
+          Say Y here if you want to use the
+	  amlogic gpiolib expand.
+

drivers/gpio/Makefile

@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+ccflags-y += -I$(srctree)/drivers/gpio
+
+MODULE_NAME = amlogic-gpiolib
+obj-$(CONFIG_AMLOGIC_GPIOLIB) = $(MODULE_NAME).o
+$(MODULE_NAME)-y += gpiolib.o

drivers/gpio/gpiolib.c

@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/machine.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/amlogic/gpiolib.h>
+#include <gpiolib.h>
+
+/*
+ * This descriptor validation needs to be inserted verbatim into each
+ * function taking a descriptor, so we need to use a preprocessor
+ * macro to avoid endless duplication. If the desc is NULL it is an
+ * optional GPIO and calls should just bail out.
+ */
+static int validate_desc(const struct gpio_desc *desc, const char *func)
+{
+	if (!desc)
+		return 0;
+	if (IS_ERR(desc)) {
+		pr_warn("%s: invalid GPIO (errorpointer)\n", func);
+		return PTR_ERR(desc);
+	}
+	if (!desc->gdev) {
+		pr_warn("%s: invalid GPIO (no device)\n", func);
+		return -EINVAL;
+	}
+	if (!desc->gdev->chip) {
+		dev_warn(&desc->gdev->dev,
+			 "%s: backing chip is gone\n", func);
+		return 0;
+	}
+	return 1;
+}
+
+#define VALIDATE_DESC(desc) do { \
+	int __valid = validate_desc(desc, __func__); \
+	if (__valid <= 0) \
+		return __valid; \
+	} while (0)
+
+/**
+ * gpiod_set_pull - enable pull-down/up for the gpio, or disable.
+ * @desc: descriptor of the GPIO for which to set pull
+ * @value: value to set
+ *
+ * Returns:
+ * 0 on success, %-ENOTSUPP if the controller doesn't support setting the
+ * pull.
+ */
+int gpiod_set_pull(struct gpio_desc *desc, unsigned int value)
+{
+	struct gpio_chip	*chip;
+	unsigned long		config;
+	enum pin_config_param	mode;
+
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
+	if (!chip || !chip->set_config) {
+		gpiod_dbg(desc,
+			  "%s: missing set() or set_config() operations\n",
+			  __func__);
+		return -ENOTSUPP;
+	}
+
+	switch (value) {
+	case GPIOD_PULL_DIS:
+		mode = PIN_CONFIG_BIAS_DISABLE;
+		break;
+	case GPIOD_PULL_DOWN:
+		mode = PIN_CONFIG_BIAS_PULL_DOWN;
+		break;
+	case GPIOD_PULL_UP:
+		mode = PIN_CONFIG_BIAS_PULL_UP;
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+	config = PIN_CONF_PACKED(mode, 0);
+
+	return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
+}
+EXPORT_SYMBOL_GPL(gpiod_set_pull);
+
+static int __init pinctrl_module_init(void)
+{
+	return 0;
+}
+
+static void __exit pinctrl_module_exit(void)
+{
+}
+
+module_init(pinctrl_module_init);
+module_exit(pinctrl_module_exit);
+
+MODULE_LICENSE("GPL v2");

include/linux/amlogic/gpiolib.h

@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+
+/*
+ * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
+ */
+
+#ifndef __AML_GPIO_H__
+#define __AML_GPIO_H__
+
+#include <linux/bug.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+
+enum gpiod_pull_type {
+	GPIOD_PULL_DIS = 0,
+	GPIOD_PULL_DOWN = 1,
+	GPIOD_PULL_UP = 2,
+};
+
+#ifdef CONFIG_GPIOLIB
+int gpiod_set_pull(struct gpio_desc *desc, unsigned int value);
+#else /* CONFIG_GPIOLIB */
+static inline int gpiod_set_pull(struct gpio_desc *desc, unsigned int value)
+{
+	/* GPIO can never have been requested */
+	WARN_ON(1);
+	return -EINVAL;
+}
+#endif /* CONFIG_GPIOLIB */
+
+#endif //__AML_GPIO_H__