diff options
Diffstat (limited to 'target/linux/ipq806x/patches-4.1/030-hwspinlock-core-add-device-tree-support.patch')
| -rw-r--r-- | target/linux/ipq806x/patches-4.1/030-hwspinlock-core-add-device-tree-support.patch | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/target/linux/ipq806x/patches-4.1/030-hwspinlock-core-add-device-tree-support.patch b/target/linux/ipq806x/patches-4.1/030-hwspinlock-core-add-device-tree-support.patch new file mode 100644 index 0000000..04f35b7 --- /dev/null +++ b/target/linux/ipq806x/patches-4.1/030-hwspinlock-core-add-device-tree-support.patch @@ -0,0 +1,167 @@ +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; |