Kumar, On 09/27/2013 11:04 AM, Kumar Gala wrote: > > On Sep 17, 2013, at 2:30 PM, Suman Anna wrote: > >> 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; > > Checking !dn is done in of_property_read_u32, so you don't need to duplicate I have added this specifically since my intention is to differentiate the validity of the node vs the presence of the property within a node. This property may be optional for some platforms and a must for some others, and differentiating would allow the individual driver implementations to make the distinction. > >> + >> + 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; > > Checking !dn is done in of_property_read_u32, so you don't need to duplicate Same comment as above. regards Suman > >> + >> + 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 > -- 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
