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authorJohn Crispin <john@openwrt.org>2013-06-23 15:50:49 +0000
committerJohn Crispin <john@openwrt.org>2013-06-23 15:50:49 +0000
commit55fb6f3a05deb4a8b5e600cc10bae9555a9f90be (patch)
treea2ef24cfc434f5eb47364d944947588c5d51fc69 /target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch
parent43a3d87b8370872c5720b4bb6616b797486d38d8 (diff)
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ralink: update patches
Signed-off-by: John Crispin <blogic@openwrt.org> SVN-Revision: 37016
Diffstat (limited to 'target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch')
-rw-r--r--target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch554
1 files changed, 554 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch b/target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch
new file mode 100644
index 0000000000..900f0a2e46
--- /dev/null
+++ b/target/linux/ramips/patches-3.9/0154-reset-Add-reset-controller-API.patch
@@ -0,0 +1,554 @@
+From d6cfbdfa001891894efe078a49ad82ac8a932dbb Mon Sep 17 00:00:00 2001
+From: John Crispin <blogic@openwrt.org>
+Date: Mon, 20 May 2013 15:42:01 +0200
+Subject: [PATCH 154/164] reset: Add reset controller API
+
+backport from v3.10-rc1
+61fc41317666be400802ac793f47de816ef7bd57
+6034bb22d8387708075c083385e5d2e1072a4f33
+4e11f848c65b1c87782cb232a6e3b47a9d4c1f98
+
+This adds a simple API for devices to request being reset
+by separate reset controller hardware and implements the
+reset signal device tree binding.
+
+Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
+Reviewed-by: Stephen Warren <swarren@nvidia.com>
+Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
+Reviewed-by: Marek Vasut <marex@denx.de>
+Reviewed-by: Pavel Machek <pavel@ucw.cz>
+---
+ Documentation/devicetree/bindings/reset/reset.txt | 75 ++++++
+ drivers/Kconfig | 2 +
+ drivers/Makefile | 3 +
+ drivers/reset/Kconfig | 13 +
+ drivers/reset/Makefile | 1 +
+ drivers/reset/core.c | 297 +++++++++++++++++++++
+ include/linux/reset-controller.h | 51 ++++
+ include/linux/reset.h | 17 ++
+ 8 files changed, 459 insertions(+)
+ create mode 100644 Documentation/devicetree/bindings/reset/reset.txt
+ create mode 100644 drivers/reset/Kconfig
+ create mode 100644 drivers/reset/Makefile
+ create mode 100644 drivers/reset/core.c
+ create mode 100644 include/linux/reset-controller.h
+ create mode 100644 include/linux/reset.h
+
+diff --git a/Documentation/devicetree/bindings/reset/reset.txt b/Documentation/devicetree/bindings/reset/reset.txt
+new file mode 100644
+index 0000000..31db6ff
+--- /dev/null
++++ b/Documentation/devicetree/bindings/reset/reset.txt
+@@ -0,0 +1,75 @@
++= Reset Signal Device Tree Bindings =
++
++This binding is intended to represent the hardware reset signals present
++internally in most IC (SoC, FPGA, ...) designs. Reset signals for whole
++standalone chips are most likely better represented as GPIOs, although there
++are likely to be exceptions to this rule.
++
++Hardware blocks typically receive a reset signal. This signal is generated by
++a reset provider (e.g. power management or clock module) and received by a
++reset consumer (the module being reset, or a module managing when a sub-
++ordinate module is reset). This binding exists to represent the provider and
++consumer, and provide a way to couple the two together.
++
++A reset signal is represented by the phandle of the provider, plus a reset
++specifier - a list of DT cells that represents the reset signal within the
++provider. The length (number of cells) and semantics of the reset specifier
++are dictated by the binding of the reset provider, although common schemes
++are described below.
++
++A word on where to place reset signal consumers in device tree: It is possible
++in hardware for a reset signal to affect multiple logically separate HW blocks
++at once. In this case, it would be unwise to represent this reset signal in
++the DT node of each affected HW block, since if activated, an unrelated block
++may be reset. Instead, reset signals should be represented in the DT node
++where it makes most sense to control it; this may be a bus node if all
++children of the bus are affected by the reset signal, or an individual HW
++block node for dedicated reset signals. The intent of this binding is to give
++appropriate software access to the reset signals in order to manage the HW,
++rather than to slavishly enumerate the reset signal that affects each HW
++block.
++
++= Reset providers =
++
++Required properties:
++#reset-cells: Number of cells in a reset specifier; Typically 0 for nodes
++ with a single reset output and 1 for nodes with multiple
++ reset outputs.
++
++For example:
++
++ rst: reset-controller {
++ #reset-cells = <1>;
++ };
++
++= Reset consumers =
++
++Required properties:
++resets: List of phandle and reset specifier pairs, one pair
++ for each reset signal that affects the device, or that the
++ device manages. Note: if the reset provider specifies '0' for
++ #reset-cells, then only the phandle portion of the pair will
++ appear.
++
++Optional properties:
++reset-names: List of reset signal name strings sorted in the same order as
++ the resets property. Consumers drivers will use reset-names to
++ match reset signal names with reset specifiers.
++
++For example:
++
++ device {
++ resets = <&rst 20>;
++ reset-names = "reset";
++ };
++
++This represents a device with a single reset signal named "reset".
++
++ bus {
++ resets = <&rst 10> <&rst 11> <&rst 12> <&rst 11>;
++ reset-names = "i2s1", "i2s2", "dma", "mixer";
++ };
++
++This represents a bus that controls the reset signal of each of four sub-
++ordinate devices. Consider for example a bus that fails to operate unless no
++child device has reset asserted.
+diff --git a/drivers/Kconfig b/drivers/Kconfig
+index 202fa6d..847f8e3 100644
+--- a/drivers/Kconfig
++++ b/drivers/Kconfig
+@@ -162,4 +162,6 @@ source "drivers/irqchip/Kconfig"
+
+ source "drivers/ipack/Kconfig"
+
++source "drivers/reset/Kconfig"
++
+ endmenu
+diff --git a/drivers/Makefile b/drivers/Makefile
+index dce39a9..1a64c4c 100644
+--- a/drivers/Makefile
++++ b/drivers/Makefile
+@@ -37,6 +37,9 @@ obj-$(CONFIG_XEN) += xen/
+ # regulators early, since some subsystems rely on them to initialize
+ obj-$(CONFIG_REGULATOR) += regulator/
+
++# reset controllers early, since gpu drivers might rely on them to initialize
++obj-$(CONFIG_RESET_CONTROLLER) += reset/
++
+ # tty/ comes before char/ so that the VT console is the boot-time
+ # default.
+ obj-y += tty/
+diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
+new file mode 100644
+index 0000000..c9d04f7
+--- /dev/null
++++ b/drivers/reset/Kconfig
+@@ -0,0 +1,13 @@
++config ARCH_HAS_RESET_CONTROLLER
++ bool
++
++menuconfig RESET_CONTROLLER
++ bool "Reset Controller Support"
++ default y if ARCH_HAS_RESET_CONTROLLER
++ help
++ Generic Reset Controller support.
++
++ This framework is designed to abstract reset handling of devices
++ via GPIOs or SoC-internal reset controller modules.
++
++ If unsure, say no.
+diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
+new file mode 100644
+index 0000000..1e2d83f
+--- /dev/null
++++ b/drivers/reset/Makefile
+@@ -0,0 +1 @@
++obj-$(CONFIG_RESET_CONTROLLER) += core.o
+diff --git a/drivers/reset/core.c b/drivers/reset/core.c
+new file mode 100644
+index 0000000..d1b6089
+--- /dev/null
++++ b/drivers/reset/core.c
+@@ -0,0 +1,297 @@
++/*
++ * Reset Controller framework
++ *
++ * Copyright 2013 Philipp Zabel, Pengutronix
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License as published by
++ * the Free Software Foundation; either version 2 of the License, or
++ * (at your option) any later version.
++ */
++#include <linux/device.h>
++#include <linux/err.h>
++#include <linux/export.h>
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/of.h>
++#include <linux/reset.h>
++#include <linux/reset-controller.h>
++#include <linux/slab.h>
++
++static DEFINE_MUTEX(reset_controller_list_mutex);
++static LIST_HEAD(reset_controller_list);
++
++/**
++ * struct reset_control - a reset control
++ * @rcdev: a pointer to the reset controller device
++ * this reset control belongs to
++ * @id: ID of the reset controller in the reset
++ * controller device
++ */
++struct reset_control {
++ struct reset_controller_dev *rcdev;
++ struct device *dev;
++ unsigned int id;
++};
++
++/**
++ * of_reset_simple_xlate - translate reset_spec to the reset line number
++ * @rcdev: a pointer to the reset controller device
++ * @reset_spec: reset line specifier as found in the device tree
++ * @flags: a flags pointer to fill in (optional)
++ *
++ * This simple translation function should be used for reset controllers
++ * with 1:1 mapping, where reset lines can be indexed by number without gaps.
++ */
++int of_reset_simple_xlate(struct reset_controller_dev *rcdev,
++ const struct of_phandle_args *reset_spec)
++{
++ if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
++ return -EINVAL;
++
++ if (reset_spec->args[0] >= rcdev->nr_resets)
++ return -EINVAL;
++
++ return reset_spec->args[0];
++}
++EXPORT_SYMBOL_GPL(of_reset_simple_xlate);
++
++/**
++ * reset_controller_register - register a reset controller device
++ * @rcdev: a pointer to the initialized reset controller device
++ */
++int reset_controller_register(struct reset_controller_dev *rcdev)
++{
++ if (!rcdev->of_xlate) {
++ rcdev->of_reset_n_cells = 1;
++ rcdev->of_xlate = of_reset_simple_xlate;
++ }
++
++ mutex_lock(&reset_controller_list_mutex);
++ list_add(&rcdev->list, &reset_controller_list);
++ mutex_unlock(&reset_controller_list_mutex);
++
++ return 0;
++}
++EXPORT_SYMBOL_GPL(reset_controller_register);
++
++/**
++ * reset_controller_unregister - unregister a reset controller device
++ * @rcdev: a pointer to the reset controller device
++ */
++void reset_controller_unregister(struct reset_controller_dev *rcdev)
++{
++ mutex_lock(&reset_controller_list_mutex);
++ list_del(&rcdev->list);
++ mutex_unlock(&reset_controller_list_mutex);
++}
++EXPORT_SYMBOL_GPL(reset_controller_unregister);
++
++/**
++ * reset_control_reset - reset the controlled device
++ * @rstc: reset controller
++ */
++int reset_control_reset(struct reset_control *rstc)
++{
++ if (rstc->rcdev->ops->reset)
++ return rstc->rcdev->ops->reset(rstc->rcdev, rstc->id);
++
++ return -ENOSYS;
++}
++EXPORT_SYMBOL_GPL(reset_control_reset);
++
++/**
++ * reset_control_assert - asserts the reset line
++ * @rstc: reset controller
++ */
++int reset_control_assert(struct reset_control *rstc)
++{
++ if (rstc->rcdev->ops->assert)
++ return rstc->rcdev->ops->assert(rstc->rcdev, rstc->id);
++
++ return -ENOSYS;
++}
++EXPORT_SYMBOL_GPL(reset_control_assert);
++
++/**
++ * reset_control_deassert - deasserts the reset line
++ * @rstc: reset controller
++ */
++int reset_control_deassert(struct reset_control *rstc)
++{
++ if (rstc->rcdev->ops->deassert)
++ return rstc->rcdev->ops->deassert(rstc->rcdev, rstc->id);
++
++ return -ENOSYS;
++}
++EXPORT_SYMBOL_GPL(reset_control_deassert);
++
++/**
++ * reset_control_get - Lookup and obtain a reference to a reset controller.
++ * @dev: device to be reset by the controller
++ * @id: reset line name
++ *
++ * Returns a struct reset_control or IS_ERR() condition containing errno.
++ *
++ * Use of id names is optional.
++ */
++struct reset_control *reset_control_get(struct device *dev, const char *id)
++{
++ struct reset_control *rstc = ERR_PTR(-EPROBE_DEFER);
++ struct reset_controller_dev *r, *rcdev;
++ struct of_phandle_args args;
++ int index = 0;
++ int rstc_id;
++ int ret;
++
++ if (!dev)
++ return ERR_PTR(-EINVAL);
++
++ if (id)
++ index = of_property_match_string(dev->of_node,
++ "reset-names", id);
++ ret = of_parse_phandle_with_args(dev->of_node, "resets", "#reset-cells",
++ index, &args);
++ if (ret)
++ return ERR_PTR(ret);
++
++ mutex_lock(&reset_controller_list_mutex);
++ rcdev = NULL;
++ list_for_each_entry(r, &reset_controller_list, list) {
++ if (args.np == r->of_node) {
++ rcdev = r;
++ break;
++ }
++ }
++ of_node_put(args.np);
++
++ if (!rcdev) {
++ mutex_unlock(&reset_controller_list_mutex);
++ return ERR_PTR(-ENODEV);
++ }
++
++ rstc_id = rcdev->of_xlate(rcdev, &args);
++ if (rstc_id < 0) {
++ mutex_unlock(&reset_controller_list_mutex);
++ return ERR_PTR(rstc_id);
++ }
++
++ try_module_get(rcdev->owner);
++ mutex_unlock(&reset_controller_list_mutex);
++
++ rstc = kzalloc(sizeof(*rstc), GFP_KERNEL);
++ if (!rstc) {
++ module_put(rcdev->owner);
++ return ERR_PTR(-ENOMEM);
++ }
++
++ rstc->dev = dev;
++ rstc->rcdev = rcdev;
++ rstc->id = rstc_id;
++
++ return rstc;
++}
++EXPORT_SYMBOL_GPL(reset_control_get);
++
++/**
++ * reset_control_put - free the reset controller
++ * @rstc: reset controller
++ */
++
++void reset_control_put(struct reset_control *rstc)
++{
++ if (IS_ERR(rstc))
++ return;
++
++ module_put(rstc->rcdev->owner);
++ kfree(rstc);
++}
++EXPORT_SYMBOL_GPL(reset_control_put);
++
++static void devm_reset_control_release(struct device *dev, void *res)
++{
++ reset_control_put(*(struct reset_control **)res);
++}
++
++/**
++ * devm_reset_control_get - resource managed reset_control_get()
++ * @dev: device to be reset by the controller
++ * @id: reset line name
++ *
++ * Managed reset_control_get(). For reset controllers returned from this
++ * function, reset_control_put() is called automatically on driver detach.
++ * See reset_control_get() for more information.
++ */
++struct reset_control *devm_reset_control_get(struct device *dev, const char *id)
++{
++ struct reset_control **ptr, *rstc;
++
++ ptr = devres_alloc(devm_reset_control_release, sizeof(*ptr),
++ GFP_KERNEL);
++ if (!ptr)
++ return ERR_PTR(-ENOMEM);
++
++ rstc = reset_control_get(dev, id);
++ if (!IS_ERR(rstc)) {
++ *ptr = rstc;
++ devres_add(dev, ptr);
++ } else {
++ devres_free(ptr);
++ }
++
++ return rstc;
++}
++EXPORT_SYMBOL_GPL(devm_reset_control_get);
++
++static int devm_reset_control_match(struct device *dev, void *res, void *data)
++{
++ struct reset_control **rstc = res;
++ if (WARN_ON(!rstc || !*rstc))
++ return 0;
++ return *rstc == data;
++}
++
++/**
++ * devm_reset_control_put - resource managed reset_control_put()
++ * @rstc: reset controller to free
++ *
++ * Deallocate a reset control allocated withd devm_reset_control_get().
++ * This function will not need to be called normally, as devres will take
++ * care of freeing the resource.
++ */
++void devm_reset_control_put(struct reset_control *rstc)
++{
++ int ret;
++
++ ret = devres_release(rstc->dev, devm_reset_control_release,
++ devm_reset_control_match, rstc);
++ if (ret)
++ WARN_ON(ret);
++}
++EXPORT_SYMBOL_GPL(devm_reset_control_put);
++
++/**
++ * device_reset - find reset controller associated with the device
++ * and perform reset
++ * @dev: device to be reset by the controller
++ *
++ * Convenience wrapper for reset_control_get() and reset_control_reset().
++ * This is useful for the common case of devices with single, dedicated reset
++ * lines.
++ */
++int device_reset(struct device *dev)
++{
++ struct reset_control *rstc;
++ int ret;
++
++ rstc = reset_control_get(dev, NULL);
++ if (IS_ERR(rstc))
++ return PTR_ERR(rstc);
++
++ ret = reset_control_reset(rstc);
++
++ reset_control_put(rstc);
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(device_reset);
+diff --git a/include/linux/reset-controller.h b/include/linux/reset-controller.h
+new file mode 100644
+index 0000000..2f61311
+--- /dev/null
++++ b/include/linux/reset-controller.h
+@@ -0,0 +1,51 @@
++#ifndef _LINUX_RESET_CONTROLLER_H_
++#define _LINUX_RESET_CONTROLLER_H_
++
++#include <linux/list.h>
++
++struct reset_controller_dev;
++
++/**
++ * struct reset_control_ops
++ *
++ * @reset: for self-deasserting resets, does all necessary
++ * things to reset the device
++ * @assert: manually assert the reset line, if supported
++ * @deassert: manually deassert the reset line, if supported
++ */
++struct reset_control_ops {
++ int (*reset)(struct reset_controller_dev *rcdev, unsigned long id);
++ int (*assert)(struct reset_controller_dev *rcdev, unsigned long id);
++ int (*deassert)(struct reset_controller_dev *rcdev, unsigned long id);
++};
++
++struct module;
++struct device_node;
++
++/**
++ * struct reset_controller_dev - reset controller entity that might
++ * provide multiple reset controls
++ * @ops: a pointer to device specific struct reset_control_ops
++ * @owner: kernel module of the reset controller driver
++ * @list: internal list of reset controller devices
++ * @of_node: corresponding device tree node as phandle target
++ * @of_reset_n_cells: number of cells in reset line specifiers
++ * @of_xlate: translation function to translate from specifier as found in the
++ * device tree to id as given to the reset control ops
++ * @nr_resets: number of reset controls in this reset controller device
++ */
++struct reset_controller_dev {
++ struct reset_control_ops *ops;
++ struct module *owner;
++ struct list_head list;
++ struct device_node *of_node;
++ int of_reset_n_cells;
++ int (*of_xlate)(struct reset_controller_dev *rcdev,
++ const struct of_phandle_args *reset_spec);
++ unsigned int nr_resets;
++};
++
++int reset_controller_register(struct reset_controller_dev *rcdev);
++void reset_controller_unregister(struct reset_controller_dev *rcdev);
++
++#endif
+diff --git a/include/linux/reset.h b/include/linux/reset.h
+new file mode 100644
+index 0000000..6082247
+--- /dev/null
++++ b/include/linux/reset.h
+@@ -0,0 +1,17 @@
++#ifndef _LINUX_RESET_H_
++#define _LINUX_RESET_H_
++
++struct device;
++struct reset_control;
++
++int reset_control_reset(struct reset_control *rstc);
++int reset_control_assert(struct reset_control *rstc);
++int reset_control_deassert(struct reset_control *rstc);
++
++struct reset_control *reset_control_get(struct device *dev, const char *id);
++void reset_control_put(struct reset_control *rstc);
++struct reset_control *devm_reset_control_get(struct device *dev, const char *id);
++
++int device_reset(struct device *dev);
++
++#endif
+--
+1.7.10.4
+