+++ /dev/null
-From fb7737e949e31d8a71acee6bbb670f32dbd2a2c0 Mon Sep 17 00:00:00 2001
-From: Suman Anna <s-anna@ti.com>
-Date: Wed, 4 Mar 2015 20:01:14 -0600
-Subject: [PATCH] hwspinlock/core: add device tree support
-
-This patch adds a new OF-friendly API of_hwspin_lock_get_id()
-for hwspinlock clients to use/request locks from a hwspinlock
-device instantiated through a device-tree blob. This new API
-can be used by hwspinlock clients to get the id for a specific
-lock using the phandle + args specifier, so that it can be
-requested using the available hwspin_lock_request_specific()
-API.
-
-Signed-off-by: Suman Anna <s-anna@ti.com>
-Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
-[small comment clarification]
-Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
----
- Documentation/hwspinlock.txt | 10 +++++
- drivers/hwspinlock/hwspinlock_core.c | 79 ++++++++++++++++++++++++++++++++++++
- include/linux/hwspinlock.h | 7 ++++
- 3 files changed, 96 insertions(+)
-
---- a/Documentation/hwspinlock.txt
-+++ b/Documentation/hwspinlock.txt
-@@ -48,6 +48,16 @@ independent, drivers.
- ids for predefined purposes.
- Should be called from a process context (might sleep).
-
-+ int of_hwspin_lock_get_id(struct device_node *np, int index);
-+ - retrieve the global lock id for an OF phandle-based specific lock.
-+ This function provides a means for DT users of a hwspinlock module
-+ to get the global lock id of a specific hwspinlock, so that it can
-+ be requested using the normal hwspin_lock_request_specific() API.
-+ The function returns a lock id number on success, -EPROBE_DEFER if
-+ the hwspinlock device is not yet registered with the core, or other
-+ error values.
-+ Should be called from a process context (might sleep).
-+
- int hwspin_lock_free(struct hwspinlock *hwlock);
- - free a previously-assigned hwspinlock; returns 0 on success, or an
- appropriate error code on failure (e.g. -EINVAL if the hwspinlock
---- a/drivers/hwspinlock/hwspinlock_core.c
-+++ b/drivers/hwspinlock/hwspinlock_core.c
-@@ -27,6 +27,7 @@
- #include <linux/hwspinlock.h>
- #include <linux/pm_runtime.h>
- #include <linux/mutex.h>
-+#include <linux/of.h>
-
- #include "hwspinlock_internal.h"
-
-@@ -257,6 +258,84 @@ void __hwspin_unlock(struct hwspinlock *
- }
- EXPORT_SYMBOL_GPL(__hwspin_unlock);
-
-+/**
-+ * of_hwspin_lock_simple_xlate - translate hwlock_spec to return a lock id
-+ * @bank: the hwspinlock device bank
-+ * @hwlock_spec: hwlock specifier as found in the device tree
-+ *
-+ * This is a simple translation function, suitable for hwspinlock platform
-+ * drivers that only has a lock specifier length of 1.
-+ *
-+ * Returns a relative index of the lock within a specified bank on success,
-+ * or -EINVAL on invalid specifier cell count.
-+ */
-+static inline int
-+of_hwspin_lock_simple_xlate(const struct of_phandle_args *hwlock_spec)
-+{
-+ if (WARN_ON(hwlock_spec->args_count != 1))
-+ return -EINVAL;
-+
-+ return hwlock_spec->args[0];
-+}
-+
-+/**
-+ * of_hwspin_lock_get_id() - get lock id for an OF phandle-based specific lock
-+ * @np: device node from which to request the specific hwlock
-+ * @index: index of the hwlock in the list of values
-+ *
-+ * This function provides a means for DT users of the hwspinlock module to
-+ * get the global lock id of a specific hwspinlock using the phandle of the
-+ * hwspinlock device, so that it can be requested using the normal
-+ * hwspin_lock_request_specific() API.
-+ *
-+ * Returns the global lock id number on success, -EPROBE_DEFER if the hwspinlock
-+ * device is not yet registered, -EINVAL on invalid args specifier value or an
-+ * appropriate error as returned from the OF parsing of the DT client node.
-+ */
-+int of_hwspin_lock_get_id(struct device_node *np, int index)
-+{
-+ struct of_phandle_args args;
-+ struct hwspinlock *hwlock;
-+ struct radix_tree_iter iter;
-+ void **slot;
-+ int id;
-+ int ret;
-+
-+ ret = of_parse_phandle_with_args(np, "hwlocks", "#hwlock-cells", index,
-+ &args);
-+ if (ret)
-+ return ret;
-+
-+ /* Find the hwspinlock device: we need its base_id */
-+ ret = -EPROBE_DEFER;
-+ rcu_read_lock();
-+ radix_tree_for_each_slot(slot, &hwspinlock_tree, &iter, 0) {
-+ hwlock = radix_tree_deref_slot(slot);
-+ if (unlikely(!hwlock))
-+ continue;
-+
-+ if (hwlock->bank->dev->of_node == args.np) {
-+ ret = 0;
-+ break;
-+ }
-+ }
-+ rcu_read_unlock();
-+ if (ret < 0)
-+ goto out;
-+
-+ id = of_hwspin_lock_simple_xlate(&args);
-+ if (id < 0 || id >= hwlock->bank->num_locks) {
-+ ret = -EINVAL;
-+ goto out;
-+ }
-+ id += hwlock->bank->base_id;
-+
-+out:
-+ of_node_put(args.np);
-+ return ret ? ret : id;
-+}
-+EXPORT_SYMBOL_GPL(of_hwspin_lock_get_id);
-+
- static int hwspin_lock_register_single(struct hwspinlock *hwlock, int id)
- {
- struct hwspinlock *tmp;
---- a/include/linux/hwspinlock.h
-+++ b/include/linux/hwspinlock.h
-@@ -26,6 +26,7 @@
- #define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */
-
- struct device;
-+struct device_node;
- struct hwspinlock;
- struct hwspinlock_device;
- struct hwspinlock_ops;
-@@ -66,6 +67,7 @@ int hwspin_lock_unregister(struct hwspin
- struct hwspinlock *hwspin_lock_request(void);
- struct hwspinlock *hwspin_lock_request_specific(unsigned int id);
- int hwspin_lock_free(struct hwspinlock *hwlock);
-+int of_hwspin_lock_get_id(struct device_node *np, int index);
- int hwspin_lock_get_id(struct hwspinlock *hwlock);
- int __hwspin_lock_timeout(struct hwspinlock *, unsigned int, int,
- unsigned long *);
-@@ -120,6 +122,11 @@ void __hwspin_unlock(struct hwspinlock *
- {
- }
-
-+static inline int of_hwspin_lock_get_id(struct device_node *np, int index)
-+{
-+ return 0;
-+}
-+
- static inline int hwspin_lock_get_id(struct hwspinlock *hwlock)
- {
- return 0;
projects / openwrt / staging / lynxis / omap.git / blobdiff