From 0cc20912b376305452cdc5c8e7b97e156ba90e93 Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Wed, 8 May 2013 22:08:39 +0200
Subject: [PATCH 28/33] reset: MIPS: ralink: add core/device reset wrapper

Add a helper for reseting different devices ont he SoC.

Signed-off-by: John Crispin <blogic@openwrt.org>
---
 arch/mips/Kconfig        |    1 +
 arch/mips/ralink/of.c    |   59 ++++++++++++++++++++++++++++++++++++++++++++++
 arch/mips/ralink/reset.c |    1 +
 3 files changed, 61 insertions(+)

--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -444,6 +444,7 @@ config RALINK
 	select HAVE_MACH_CLKDEV
 	select CLKDEV_LOOKUP
 	select ARCH_REQUIRE_GPIOLIB
+	select ARCH_HAS_RESET_CONTROLLER
 
 config SGI_IP22
 	bool "SGI IP22 (Indy/Indigo2)"
--- a/arch/mips/ralink/of.c
+++ b/arch/mips/ralink/of.c
@@ -14,16 +14,22 @@
 #include <linux/sizes.h>
 #include <linux/of_fdt.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/bootmem.h>
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
+#include <linux/reset-controller.h>
 
 #include <asm/reboot.h>
 #include <asm/bootinfo.h>
 #include <asm/addrspace.h>
 
+#include <asm/mach-ralink/ralink_regs.h>
+
 #include "common.h"
 
+#define SYSC_REG_RESET_CTRL     0x034
+
 __iomem void *rt_sysc_membase;
 __iomem void *rt_memc_membase;
 
@@ -96,6 +102,53 @@ void __init plat_mem_setup(void)
 				     soc_info.mem_size_max * SZ_1M);
 }
 
+static int ralink_assert_device(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	u32 val;
+
+	if (id < 8)
+		return -1;
+
+	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+	val |= BIT(id);
+	rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+	return 0;
+}
+
+static int ralink_deassert_device(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	u32 val;
+
+	if (id < 8)
+		return -1;
+
+	val = rt_sysc_r32(SYSC_REG_RESET_CTRL);
+	val &= ~BIT(id);
+	rt_sysc_w32(val, SYSC_REG_RESET_CTRL);
+
+	return 0;
+}
+
+static int ralink_reset_device(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	ralink_assert_device(rcdev, id);
+	return ralink_deassert_device(rcdev, id);
+}
+
+static struct reset_control_ops reset_ops = {
+	.reset = ralink_reset_device,
+	.assert = ralink_assert_device,
+	.deassert = ralink_deassert_device,
+};
+
+static struct reset_controller_dev reset_dev = {
+	.ops			= &reset_ops,
+	.owner			= THIS_MODULE,
+	.nr_resets		= 32,
+	.of_reset_n_cells	= 1,
+};
+
 static int __init plat_of_setup(void)
 {
 	static struct of_device_id of_ids[3];
@@ -110,6 +163,12 @@ static int __init plat_of_setup(void)
 	if (of_platform_populate(NULL, of_ids, NULL, NULL))
 		panic("failed to populate DT\n");
 
+	reset_dev.of_node = of_find_compatible_node(NULL, NULL, "ralink,rt2880-reset");
+	if (!reset_dev.of_node)
+		panic("Failed to find reset controller node");
+
+	reset_controller_register(&reset_dev);
+
 	ralink_pinmux();
 
 	return 0;
--- a/arch/mips/ralink/reset.c
+++ b/arch/mips/ralink/reset.c
@@ -10,6 +10,7 @@
 
 #include <linux/pm.h>
 #include <linux/io.h>
+#include <linux/module.h>
 
 #include <asm/reboot.h>