All the platform-specific hwlock driver implementations need the number of locks and the associated base id for registering the locks present within a hwspinlock device with the driver core. These two variables are represented by 'hwlock-num-locks' and 'hwlock-base-id' properties. The documentation and OF helpers to retrieve these common properties have been added to the driver core. Signed-off-by: Suman Anna <s-anna@xxxxxx> --- .../devicetree/bindings/hwlock/hwlock.txt | 26 +++++++++ drivers/hwspinlock/hwspinlock_core.c | 61 +++++++++++++++++++++- include/linux/hwspinlock.h | 11 ++-- 3 files changed, 93 insertions(+), 5 deletions(-) create mode 100644 Documentation/devicetree/bindings/hwlock/hwlock.txt diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt new file mode 100644 index 0000000..789930e --- /dev/null +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt @@ -0,0 +1,26 @@ +Generic hwlock bindings +======================= + +Generic bindings that are common to all the hwlock platform specific driver +implementations, the retrieved values are used for registering the device +specific parameters with the hwspinlock core. + +The validity and need of these common properties may vary from one driver +implementation to another. Look through the individual hwlock driver +binding documentations for identifying which are mandatory and which are +optional for that specific driver. + +Common properties: +- hwlock-base-id: Base Id for the locks for a particular hwlock device. + This property is used for representing a set of locks + present in a hwlock device with a unique base id in + the driver core. This property is mandatory ONLY if a + SoC has several hwlock devices. + + See documentation on struct hwspinlock_pdata in + linux/hwspinlock.h for more details. + +- hwlock-num-locks: Number of locks present in a hwlock device. This + property is needed on hwlock devices, where the number + of supported locks within a hwlock device cannot be + read from a register. diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 461a0d7..aec32e7 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -1,7 +1,7 @@ /* * Hardware spinlock framework * - * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com * * Contact: Ohad Ben-Cohen <ohad@xxxxxxxxxx> * @@ -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" @@ -308,6 +309,64 @@ out: } /** + * of_hwspin_lock_get_base_id() - OF helper to retrieve base id + * @dn: device node pointer + * + * This is an OF helper function that can be called by the underlying + * platform-specific implementations, to retrieve the base id for the + * set of locks present within a hwspinlock device instance. + * + * Returns the base id value on success, -ENODEV on generic failure or + * an appropriate error code as returned by the OF layer + */ +int of_hwspin_lock_get_base_id(struct device_node *dn) +{ + unsigned int val; + int ret = -ENODEV; + +#ifdef CONFIG_OF + if (!dn) + return -ENODEV; + + ret = of_property_read_u32(dn, "hwlock-base-id", &val); + if (!ret) + ret = val; +#endif + + return ret; +} +EXPORT_SYMBOL_GPL(of_hwspin_lock_get_base_id); + +/** + * of_hwspin_lock_get_num_locks() - OF helper to retrieve number of locks + * @dn: device node pointer + * + * This is an OF helper function that can be called by the underlying + * platform-specific implementations, to retrieve the number of locks + * present within a hwspinlock device instance. + * + * Returns a positive number of locks on success, -ENODEV on generic + * failure or an appropriate error code as returned by the OF layer + */ +int of_hwspin_lock_get_num_locks(struct device_node *dn) +{ + unsigned int val; + int ret = -ENODEV; + +#ifdef CONFIG_OF + if (!dn) + return -ENODEV; + + ret = of_property_read_u32(dn, "hwlock-num-locks", &val); + if (!ret) + ret = val ? val : -ENODEV; +#endif + + return ret; +} +EXPORT_SYMBOL_GPL(of_hwspin_lock_get_num_locks); + +/** * hwspin_lock_register() - register a new hw spinlock device * @bank: the hwspinlock device, which usually provides numerous hw locks * @dev: the backing device diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index 3343298..1f6a5b8 100644 --- a/include/linux/hwspinlock.h +++ b/include/linux/hwspinlock.h @@ -1,7 +1,7 @@ /* * Hardware spinlock public header * - * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com * * Contact: Ohad Ben-Cohen <ohad@xxxxxxxxxx> * @@ -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; @@ -60,6 +61,8 @@ struct hwspinlock_pdata { #if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE) +int of_hwspin_lock_get_base_id(struct device_node *dn); +int of_hwspin_lock_get_num_locks(struct device_node *dn); int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev, const struct hwspinlock_ops *ops, int base_id, int num_locks); int hwspin_lock_unregister(struct hwspinlock_device *bank); @@ -80,9 +83,9 @@ void __hwspin_unlock(struct hwspinlock *, int, unsigned long *); * code path get compiled away. This way, if CONFIG_HWSPINLOCK is not * required on a given setup, users will still work. * - * The only exception is hwspin_lock_register/hwspin_lock_unregister, with which - * we _do_ want users to fail (no point in registering hwspinlock instances if - * the framework is not available). + * The only exception is hwspin_lock_register/hwspin_lock_unregister and + * associated OF helpers, with which we _do_ want users to fail (no point + * in registering hwspinlock instances if the framework is not available). * * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking * users. Others, which care, can still check this with IS_ERR. -- 1.8.3.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html