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-rw-r--r--target/mips/mikrotik-rb4xx/patches/3.14.26/0008-gpio-add-GPIO-latch-driver.patch290
1 files changed, 290 insertions, 0 deletions
diff --git a/target/mips/mikrotik-rb4xx/patches/3.14.26/0008-gpio-add-GPIO-latch-driver.patch b/target/mips/mikrotik-rb4xx/patches/3.14.26/0008-gpio-add-GPIO-latch-driver.patch
new file mode 100644
index 000000000..188cec3b2
--- /dev/null
+++ b/target/mips/mikrotik-rb4xx/patches/3.14.26/0008-gpio-add-GPIO-latch-driver.patch
@@ -0,0 +1,290 @@
+From dd93d7e5b6530f1574860776fe6f960c4fd2661d Mon Sep 17 00:00:00 2001
+From: Phil Sutter <phil@nwl.cc>
+Date: Tue, 13 May 2014 00:21:54 +0200
+Subject: [PATCH] gpio: add GPIO latch driver
+
+---
+ drivers/gpio/Kconfig | 7 +
+ drivers/gpio/Makefile | 1 +
+ drivers/gpio/gpio-latch.c | 219 +++++++++++++++++++++++++++++++
+ include/linux/platform_data/gpio-latch.h | 14 ++
+ 4 files changed, 241 insertions(+)
+ create mode 100644 drivers/gpio/gpio-latch.c
+ create mode 100644 include/linux/platform_data/gpio-latch.h
+
+diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
+index 903f24d..905730b 100644
+--- a/drivers/gpio/Kconfig
++++ b/drivers/gpio/Kconfig
+@@ -834,4 +834,11 @@ config GPIO_VIPERBOARD
+ River Tech's viperboard.h for detailed meaning
+ of the module parameters.
+
++comment "Other GPIO expanders"
++
++config GPIO_LATCH
++ tristate "GPIO latch driver"
++ help
++ Say yes here to enable a GPIO latch driver.
++
+ endif
+diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
+index 5d50179..7d03524 100644
+--- a/drivers/gpio/Makefile
++++ b/drivers/gpio/Makefile
+@@ -36,6 +36,7 @@ obj-$(CONFIG_GPIO_KEMPLD) += gpio-kempld.o
+ obj-$(CONFIG_ARCH_KS8695) += gpio-ks8695.o
+ obj-$(CONFIG_GPIO_INTEL_MID) += gpio-intel-mid.o
+ obj-$(CONFIG_GPIO_LP3943) += gpio-lp3943.o
++obj-$(CONFIG_GPIO_LATCH) += gpio-latch.o
+ obj-$(CONFIG_ARCH_LPC32XX) += gpio-lpc32xx.o
+ obj-$(CONFIG_GPIO_LYNXPOINT) += gpio-lynxpoint.o
+ obj-$(CONFIG_GPIO_MAX730X) += gpio-max730x.o
+diff --git a/drivers/gpio/gpio-latch.c b/drivers/gpio/gpio-latch.c
+new file mode 100644
+index 0000000..1efa1a1
+--- /dev/null
++++ b/drivers/gpio/gpio-latch.c
+@@ -0,0 +1,219 @@
++/*
++ * GPIO latch driver
++ *
++ * Copyright (C) 2014 Gabor Juhos <juhosg@openwrt.org>
++ *
++ * This program is free software; you can redistribute it and/or modify it
++ * under the terms of the GNU General Public License version 2 as published
++ * by the Free Software Foundation.
++ */
++
++#include <linux/kernel.h>
++#include <linux/init.h>
++#include <linux/module.h>
++#include <linux/types.h>
++#include <linux/gpio.h>
++#include <linux/slab.h>
++#include <linux/platform_device.h>
++
++#include <linux/platform_data/gpio-latch.h>
++
++struct gpio_latch_chip {
++ struct gpio_chip gc;
++
++ struct mutex mutex;
++ struct mutex latch_mutex;
++ bool latch_enabled;
++ int le_gpio;
++ bool le_active_low;
++ int *gpios;
++};
++
++static inline struct gpio_latch_chip *to_gpio_latch_chip(struct gpio_chip *gc)
++{
++ return container_of(gc, struct gpio_latch_chip, gc);
++}
++
++static void gpio_latch_lock(struct gpio_latch_chip *glc, bool enable)
++{
++ mutex_lock(&glc->mutex);
++
++ if (enable)
++ glc->latch_enabled = true;
++
++ if (glc->latch_enabled)
++ mutex_lock(&glc->latch_mutex);
++}
++
++static void gpio_latch_unlock(struct gpio_latch_chip *glc, bool disable)
++{
++ if (glc->latch_enabled)
++ mutex_unlock(&glc->latch_mutex);
++
++ if (disable)
++ glc->latch_enabled = true;
++
++ mutex_unlock(&glc->mutex);
++}
++
++static int
++gpio_latch_get(struct gpio_chip *gc, unsigned offset)
++{
++ struct gpio_latch_chip *glc = to_gpio_latch_chip(gc);
++ int ret;
++
++ gpio_latch_lock(glc, false);
++ ret = gpio_get_value(glc->gpios[offset]);
++ gpio_latch_unlock(glc, false);
++
++ return ret;
++}
++
++static void
++gpio_latch_set(struct gpio_chip *gc, unsigned offset, int value)
++{
++ struct gpio_latch_chip *glc = to_gpio_latch_chip(gc);
++ bool enable_latch = false;
++ bool disable_latch = false;
++ int gpio;
++
++ gpio = glc->gpios[offset];
++
++ if (gpio == glc->le_gpio) {
++ enable_latch = value ^ glc->le_active_low;
++ disable_latch = !enable_latch;
++ }
++
++ gpio_latch_lock(glc, enable_latch);
++ gpio_set_value(gpio, value);
++ gpio_latch_unlock(glc, disable_latch);
++}
++
++static int
++gpio_latch_direction_input(struct gpio_chip *gc, unsigned offset)
++{
++ struct gpio_latch_chip *glc = to_gpio_latch_chip(gc);
++ int ret;
++
++ gpio_latch_lock(glc, false);
++ ret = gpio_direction_input(glc->gpios[offset]);
++ gpio_latch_unlock(glc, false);
++
++ return ret;
++}
++
++static int
++gpio_latch_direction_output(struct gpio_chip *gc, unsigned offset, int value)
++{
++ struct gpio_latch_chip *glc = to_gpio_latch_chip(gc);
++ bool enable_latch = false;
++ bool disable_latch = false;
++ int gpio;
++ int ret;
++
++ gpio = glc->gpios[offset];
++
++ if (gpio == glc->le_gpio) {
++ enable_latch = value ^ glc->le_active_low;
++ disable_latch = !enable_latch;
++ }
++
++ gpio_latch_lock(glc, enable_latch);
++ ret = gpio_direction_output(gpio, value);
++ gpio_latch_unlock(glc, disable_latch);
++
++ return ret;
++}
++
++static int gpio_latch_probe(struct platform_device *pdev)
++{
++ struct gpio_latch_chip *glc;
++ struct gpio_latch_platform_data *pdata;
++ struct gpio_chip *gc;
++ int size;
++ int ret;
++ int i;
++
++ pdata = dev_get_platdata(&pdev->dev);
++ if (!pdata)
++ return -EINVAL;
++
++ if (pdata->le_gpio_index >= pdata->num_gpios ||
++ !pdata->num_gpios ||
++ !pdata->gpios)
++ return -EINVAL;
++
++ for (i = 0; i < pdata->num_gpios; i++) {
++ int gpio = pdata->gpios[i];
++
++ ret = devm_gpio_request(&pdev->dev, gpio,
++ GPIO_LATCH_DRIVER_NAME);
++ if (ret)
++ return ret;
++ }
++
++ glc = devm_kzalloc(&pdev->dev, sizeof(*glc), GFP_KERNEL);
++ if (!glc)
++ return -ENOMEM;
++
++ mutex_init(&glc->mutex);
++ mutex_init(&glc->latch_mutex);
++
++ size = pdata->num_gpios * sizeof(glc->gpios[0]);
++ glc->gpios = devm_kzalloc(&pdev->dev, size , GFP_KERNEL);
++ if (!glc->gpios)
++ return -ENOMEM;
++
++ memcpy(glc->gpios, pdata->gpios, size);
++
++ glc->le_gpio = glc->gpios[pdata->le_gpio_index];
++ glc->le_active_low = pdata->le_active_low;
++
++ gc = &glc->gc;
++
++ gc->label = GPIO_LATCH_DRIVER_NAME;
++ gc->base = pdata->base;
++ gc->can_sleep = true;
++ gc->ngpio = pdata->num_gpios;
++ gc->get = gpio_latch_get;
++ gc->set = gpio_latch_set;
++ gc->direction_input = gpio_latch_direction_input,
++ gc->direction_output = gpio_latch_direction_output;
++
++ platform_set_drvdata(pdev, glc);
++
++ ret = gpiochip_add(&glc->gc);
++ if (ret)
++ return ret;
++
++ return 0;
++}
++
++static int gpio_latch_remove(struct platform_device *pdev)
++{
++ struct gpio_latch_chip *glc = platform_get_drvdata(pdev);
++
++ return gpiochip_remove(&glc->gc);;
++}
++
++
++static struct platform_driver gpio_latch_driver = {
++ .probe = gpio_latch_probe,
++ .remove = gpio_latch_remove,
++ .driver = {
++ .name = GPIO_LATCH_DRIVER_NAME,
++ .owner = THIS_MODULE,
++ },
++};
++
++static int __init gpio_latch_init(void)
++{
++ return platform_driver_register(&gpio_latch_driver);
++}
++
++postcore_initcall(gpio_latch_init);
++
++MODULE_DESCRIPTION("GPIO latch driver");
++MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
++MODULE_LICENSE("GPL v2");
++MODULE_ALIAS("platform:" GPIO_LATCH_DRIVER_NAME);
+diff --git a/include/linux/platform_data/gpio-latch.h b/include/linux/platform_data/gpio-latch.h
+new file mode 100644
+index 0000000..0450e67
+--- /dev/null
++++ b/include/linux/platform_data/gpio-latch.h
+@@ -0,0 +1,14 @@
++#ifndef _GPIO_LATCH_H_
++#define _GPIO_LATCH_H_
++
++#define GPIO_LATCH_DRIVER_NAME "gpio-latch"
++
++struct gpio_latch_platform_data {
++ int base;
++ int num_gpios;
++ int *gpios;
++ int le_gpio_index;
++ bool le_active_low;
++};
++
++#endif /* _GPIO_LATCH_H_ */
+--
+1.8.5.3
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-26 04:56:34 +0000