| Message ID | 1398904476-26200-9-git-send-email-s-anna@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 30, 2014 at 7:34 PM, Suman Anna <s-anna@ti.com> wrote: > The HwSpinlock core requires a base id for registering a bank > of hwspinlocks. This base id needs to be unique across multiple > IP instances of a hwspinlock device, so that each hwlock can be > represented uniquely in a system. > > Support has been added to represent this in DT through a common > property 'hwlock-base-id', and retrieve the value through a core > OF helper function, of_hwspin_lock_get_base_id(). The representation > in DT provides a uniform way of assigning a fixed base value for a > hwspinlock device across different SoCs. > > Signed-off-by: Suman Anna <s-anna@ti.com> > --- > Documentation/devicetree/bindings/hwlock/hwlock.txt | 6 ++++++ > drivers/hwspinlock/hwspinlock_core.c | 21 +++++++++++++++++++++ > include/linux/hwspinlock.h | 1 + > 3 files changed, 28 insertions(+) > > diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt > index 32381cc..d538a9b 100644 > --- a/Documentation/devicetree/bindings/hwlock/hwlock.txt > +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt > @@ -18,6 +18,12 @@ Common properties: > property is needed on hwlock devices, where the number > of supported locks within a hwlock device cannot be > read from a register. > +- hwlock-base-id: An unique base Id for the locks for a particular hwlock > + device. This property is mandatory ONLY if a SoC has > + several hwlock devices. > + > + See documentation on struct hwspinlock_pdata in > + include/linux/hwspinlock.h for more details. The documentation cannot refer to kernel files. Generally, creating a global number space like this would not be accepted, but I don't really have any better idea here. Please put all binding docs in 1 patch and copy all the DT binding maintainers. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Rob, On 05/05/2014 03:37 PM, Rob Herring wrote: > On Wed, Apr 30, 2014 at 7:34 PM, Suman Anna <s-anna@ti.com> wrote: >> The HwSpinlock core requires a base id for registering a bank >> of hwspinlocks. This base id needs to be unique across multiple >> IP instances of a hwspinlock device, so that each hwlock can be >> represented uniquely in a system. >> >> Support has been added to represent this in DT through a common >> property 'hwlock-base-id', and retrieve the value through a core >> OF helper function, of_hwspin_lock_get_base_id(). The representation >> in DT provides a uniform way of assigning a fixed base value for a >> hwspinlock device across different SoCs. >> >> Signed-off-by: Suman Anna <s-anna@ti.com> >> --- >> Documentation/devicetree/bindings/hwlock/hwlock.txt | 6 ++++++ >> drivers/hwspinlock/hwspinlock_core.c | 21 +++++++++++++++++++++ >> include/linux/hwspinlock.h | 1 + >> 3 files changed, 28 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt >> index 32381cc..d538a9b 100644 >> --- a/Documentation/devicetree/bindings/hwlock/hwlock.txt >> +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt >> @@ -18,6 +18,12 @@ Common properties: >> property is needed on hwlock devices, where the number >> of supported locks within a hwlock device cannot be >> read from a register. >> +- hwlock-base-id: An unique base Id for the locks for a particular hwlock >> + device. This property is mandatory ONLY if a SoC has >> + several hwlock devices. >> + >> + See documentation on struct hwspinlock_pdata in >> + include/linux/hwspinlock.h for more details. > > The documentation cannot refer to kernel files. OK, good to know. There are couple of such existing references, so didn't think it was an issue. I will fold this patch and remove the kernel reference if this property is ok to add. > Generally, creating a > global number space like this would not be accepted, but I don't > really have any better idea here. > > Please put all binding docs in 1 patch and copy all the DT binding maintainers. I have deliberately put these in separate patches (as RFC) as there doesn't seem to be a consensus on this. I had added this originally, dropped it and brought it back again based on discussion on the previous version. Intention was either to fold into the original patch if accepted or drop them and revisit later. regards Suman -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt index 32381cc..d538a9b 100644 --- a/Documentation/devicetree/bindings/hwlock/hwlock.txt +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt @@ -18,6 +18,12 @@ Common properties: property is needed on hwlock devices, where the number of supported locks within a hwlock device cannot be read from a register. +- hwlock-base-id: An unique base Id for the locks for a particular hwlock + device. This property is mandatory ONLY if a SoC has + several hwlock devices. + + See documentation on struct hwspinlock_pdata in + include/linux/hwspinlock.h for more details. Hwlock Users: ============= diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 3966c0c..4be1664 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -264,6 +264,27 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) EXPORT_SYMBOL_GPL(__hwspin_unlock); /** + * 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, 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; + + ret = of_property_read_u32(dn, "hwlock-base-id", &val); + return ret ? ret : val; +} +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 * diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index 068e628..4857728 100644 --- a/include/linux/hwspinlock.h +++ b/include/linux/hwspinlock.h @@ -64,6 +64,7 @@ struct hwspinlock_pdata { int of_hwspin_lock_simple_xlate(struct hwspinlock_device *bank, const struct of_phandle_args *hwlock_spec); +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);
The HwSpinlock core requires a base id for registering a bank of hwspinlocks. This base id needs to be unique across multiple IP instances of a hwspinlock device, so that each hwlock can be represented uniquely in a system. Support has been added to represent this in DT through a common property 'hwlock-base-id', and retrieve the value through a core OF helper function, of_hwspin_lock_get_base_id(). The representation in DT provides a uniform way of assigning a fixed base value for a hwspinlock device across different SoCs. Signed-off-by: Suman Anna <s-anna@ti.com> --- Documentation/devicetree/bindings/hwlock/hwlock.txt | 6 ++++++ drivers/hwspinlock/hwspinlock_core.c | 21 +++++++++++++++++++++ include/linux/hwspinlock.h | 1 + 3 files changed, 28 insertions(+)