ath25: add back target support

Discussion on the mailing list reveals that this target has active
users. As we are finally able to upgrade this target to kernel 5.4,
add it back to master.

This reverts commit 7d29a5571403 ("ath25: drop target") and
immediately moves the relevant files to 5.4, without touching
the content.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

1 files changed, 212 insertions, 0 deletions

diff --git a/target/linux/ath25/patches-5.4/107-ar5312_gpio.patch b/target/linux/ath25/patches-5.4/107-ar5312_gpio.patch
new file mode 100644
index 0000000000..e74e20b05a
--- /dev/null
+++ b/target/linux/ath25/patches-5.4/107-ar5312_gpio.patch
@@ -0,0 +1,212 @@
+--- a/arch/mips/ath25/Kconfig
++++ b/arch/mips/ath25/Kconfig
+@@ -2,6 +2,7 @@
+ config SOC_AR5312
+ 	bool "Atheros AR5312/AR2312+ SoC support"
+ 	depends on ATH25
++	select GPIO_AR5312
+ 	default y
+ 
+ config SOC_AR2315
+--- a/arch/mips/ath25/ar5312.c
++++ b/arch/mips/ath25/ar5312.c
+@@ -22,6 +22,7 @@
+ #include <linux/platform_device.h>
+ #include <linux/mtd/physmap.h>
+ #include <linux/reboot.h>
++#include <linux/gpio.h>
+ #include <asm/bootinfo.h>
+ #include <asm/reboot.h>
+ #include <asm/time.h>
+@@ -180,6 +181,22 @@ static struct platform_device ar5312_phy
+ 	.num_resources = 1,
+ };
+ 
++static struct resource ar5312_gpio_res[] = {
++	{
++		.name = "ar5312-gpio",
++		.flags = IORESOURCE_MEM,
++		.start = AR5312_GPIO_BASE,
++		.end = AR5312_GPIO_BASE + AR5312_GPIO_SIZE - 1,
++	},
++};
++
++static struct platform_device ar5312_gpio = {
++	.name = "ar5312-gpio",
++	.id = -1,
++	.resource = ar5312_gpio_res,
++	.num_resources = ARRAY_SIZE(ar5312_gpio_res),
++};
++
+ static void __init ar5312_flash_init(void)
+ {
+ 	void __iomem *flashctl_base;
+@@ -247,6 +264,8 @@ void __init ar5312_init_devices(void)
+ 
+ 	platform_device_register(&ar5312_physmap_flash);
+ 
++	platform_device_register(&ar5312_gpio);
++
+ 	switch (ath25_soc) {
+ 	case ATH25_SOC_AR5312:
+ 		if (!ath25_board.radio)
+--- a/drivers/gpio/Kconfig
++++ b/drivers/gpio/Kconfig
+@@ -105,6 +105,13 @@ config GPIO_AMDPT
+ 	  driver for GPIO functionality on Promontory IOHub
+ 	  Require ACPI ASL code to enumerate as a platform device.
+ 
++config GPIO_AR5312
++	bool "AR5312 SoC GPIO support"
++	default y if SOC_AR5312
++	depends on SOC_AR5312
++	help
++	  Say yes here to enable GPIO support for Atheros AR5312/AR2312+ SoCs.
++
+ config GPIO_ASPEED
+ 	tristate "Aspeed GPIO support"
+ 	depends on (ARCH_ASPEED || COMPILE_TEST) && OF_GPIO
+--- a/drivers/gpio/Makefile
++++ b/drivers/gpio/Makefile
+@@ -29,6 +29,7 @@ obj-$(CONFIG_GPIO_ALTERA)  	+= gpio-alte
+ obj-$(CONFIG_GPIO_ALTERA_A10SR)	+= gpio-altera-a10sr.o
+ obj-$(CONFIG_GPIO_AMD8111)	+= gpio-amd8111.o
+ obj-$(CONFIG_GPIO_AMDPT)	+= gpio-amdpt.o
++obj-$(CONFIG_GPIO_AR5312)	+= gpio-ar5312.o
+ obj-$(CONFIG_GPIO_ARIZONA)	+= gpio-arizona.o
+ obj-$(CONFIG_GPIO_ATH79)	+= gpio-ath79.o
+ obj-$(CONFIG_GPIO_ASPEED)	+= gpio-aspeed.o
+--- /dev/null
++++ b/drivers/gpio/gpio-ar5312.c
+@@ -0,0 +1,121 @@
++/*
++ * This file is subject to the terms and conditions of the GNU General Public
++ * License.  See the file "COPYING" in the main directory of this archive
++ * for more details.
++ *
++ * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
++ * Copyright (C) 2006 FON Technology, SL.
++ * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
++ * Copyright (C) 2006-2009 Felix Fietkau <nbd@nbd.name>
++ * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com>
++ */
++
++#include <linux/kernel.h>
++#include <linux/init.h>
++#include <linux/platform_device.h>
++#include <linux/gpio.h>
++
++#define DRIVER_NAME	"ar5312-gpio"
++
++#define AR5312_GPIO_DO		0x00		/* output register */
++#define AR5312_GPIO_DI		0x04		/* intput register */
++#define AR5312_GPIO_CR		0x08		/* control register */
++
++#define AR5312_GPIO_CR_M(x)	(1 << (x))	/* mask for i/o */
++#define AR5312_GPIO_CR_O(x)	(0 << (x))	/* mask for output */
++#define AR5312_GPIO_CR_I(x)	(1 << (x))	/* mask for input */
++#define AR5312_GPIO_CR_INT(x)	(1 << ((x)+8))	/* mask for interrupt */
++#define AR5312_GPIO_CR_UART(x)	(1 << ((x)+16))	/* uart multiplex */
++
++#define AR5312_GPIO_NUM		8
++
++static void __iomem *ar5312_mem;
++
++static inline u32 ar5312_gpio_reg_read(unsigned reg)
++{
++	return __raw_readl(ar5312_mem + reg);
++}
++
++static inline void ar5312_gpio_reg_write(unsigned reg, u32 val)
++{
++	__raw_writel(val, ar5312_mem + reg);
++}
++
++static inline void ar5312_gpio_reg_mask(unsigned reg, u32 mask, u32 val)
++{
++	ar5312_gpio_reg_write(reg, (ar5312_gpio_reg_read(reg) & ~mask) | val);
++}
++
++static int ar5312_gpio_get_val(struct gpio_chip *chip, unsigned gpio)
++{
++	return (ar5312_gpio_reg_read(AR5312_GPIO_DI) >> gpio) & 1;
++}
++
++static void ar5312_gpio_set_val(struct gpio_chip *chip, unsigned gpio, int val)
++{
++	u32 reg = ar5312_gpio_reg_read(AR5312_GPIO_DO);
++
++	reg = val ? reg | (1 << gpio) : reg & ~(1 << gpio);
++	ar5312_gpio_reg_write(AR5312_GPIO_DO, reg);
++}
++
++static int ar5312_gpio_dir_in(struct gpio_chip *chip, unsigned gpio)
++{
++	ar5312_gpio_reg_mask(AR5312_GPIO_CR, 0, 1 << gpio);
++	return 0;
++}
++
++static int ar5312_gpio_dir_out(struct gpio_chip *chip, unsigned gpio, int val)
++{
++	ar5312_gpio_reg_mask(AR5312_GPIO_CR, 1 << gpio, 0);
++	ar5312_gpio_set_val(chip, gpio, val);
++	return 0;
++}
++
++static struct gpio_chip ar5312_gpio_chip = {
++	.label			= DRIVER_NAME,
++	.direction_input	= ar5312_gpio_dir_in,
++	.direction_output	= ar5312_gpio_dir_out,
++	.set			= ar5312_gpio_set_val,
++	.get			= ar5312_gpio_get_val,
++	.base			= 0,
++	.ngpio			= AR5312_GPIO_NUM,
++};
++
++static int ar5312_gpio_probe(struct platform_device *pdev)
++{
++	struct device *dev = &pdev->dev;
++	struct resource *res;
++	int ret;
++
++	if (ar5312_mem)
++		return -EBUSY;
++
++	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++	ar5312_mem = devm_ioremap_resource(dev, res);
++	if (IS_ERR(ar5312_mem))
++		return PTR_ERR(ar5312_mem);
++
++	ar5312_gpio_chip.parent = dev;
++	ret = gpiochip_add(&ar5312_gpio_chip);
++	if (ret) {
++		dev_err(dev, "failed to add gpiochip\n");
++		return ret;
++	}
++
++	return 0;
++}
++
++static struct platform_driver ar5312_gpio_driver = {
++	.probe = ar5312_gpio_probe,
++	.driver = {
++		.name = DRIVER_NAME,
++		.owner = THIS_MODULE,
++	}
++};
++
++static int __init ar5312_gpio_init(void)
++{
++	return platform_driver_register(&ar5312_gpio_driver);
++}
++subsys_initcall(ar5312_gpio_init);
+--- a/arch/mips/Kconfig
++++ b/arch/mips/Kconfig
+@@ -175,6 +175,7 @@ config ATH25
+ 	select CEVT_R4K
+ 	select CSRC_R4K
+ 	select DMA_NONCOHERENT
++	select GPIOLIB
+ 	select IRQ_MIPS_CPU
+ 	select IRQ_DOMAIN
+ 	select SYS_HAS_CPU_MIPS32_R1