| Message ID | 1471274620-20754-6-git-send-email-lorenzo.pieralisi@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2016/8/15 23:23, Lorenzo Pieralisi wrote: > The platform device kernel API does not provide functions to > retrieve a platform device through the corresponding struct > device fwnode pointer. > > Implement the fwnode platform_device look-up in drivers core > code by using the bus_find_device() API and a corresponding > matching function. The OF equivalent (eg of_find_device_by_node()) > will reuse the newly introduced function when OF code will > take care of setting up the device->fwnode value that is > currently left dangling for platform devices instantiated out > of device tree nodes. > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > --- > drivers/base/platform.c | 23 +++++++++++++++++++++++ > include/linux/platform_device.h | 3 +++ > 2 files changed, 26 insertions(+) > > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index 6482d47..3ef150d 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -760,6 +760,29 @@ err_out: > } > EXPORT_SYMBOL_GPL(__platform_create_bundle); > > +static int fwnode_dev_match(struct device *dev, void *data) > +{ > + return dev->fwnode == data; > +} > + > +/** > + * platform_find_device_by_fwnode() - Find the platform_device associated > + * with a fwnode > + * @fwnode: Pointer to firmware node > + * > + * Returns platform_device pointer, or NULL if not found > + */ > +struct platform_device * > +platform_find_device_by_fwnode(struct fwnode_handle *fwnode) > +{ > + struct device *dev; > + > + dev = bus_find_device(&platform_bus_type, NULL, fwnode, > + fwnode_dev_match); > + return dev ? to_platform_device(dev) : NULL; > +} > +EXPORT_SYMBOL(platform_find_device_by_fwnode); As SMMU is registered as platform devices, I think we need such API to retrieve the platform device with fwnode handle, actually Kefeng introduced a similar patch [1], but your patch is more generic, so this patch make sense to me, Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Thanks Hanjun [1]: https://patchwork.kernel.org/patch/7743661/
On Mon, Sep 05, 2016 at 09:19:43PM +0800, Hanjun Guo wrote: > On 2016/8/15 23:23, Lorenzo Pieralisi wrote: > >The platform device kernel API does not provide functions to > >retrieve a platform device through the corresponding struct > >device fwnode pointer. > > > >Implement the fwnode platform_device look-up in drivers core > >code by using the bus_find_device() API and a corresponding > >matching function. The OF equivalent (eg of_find_device_by_node()) > >will reuse the newly introduced function when OF code will > >take care of setting up the device->fwnode value that is > >currently left dangling for platform devices instantiated out > >of device tree nodes. > > > >Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> > >Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> > >Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> > >--- > > drivers/base/platform.c | 23 +++++++++++++++++++++++ > > include/linux/platform_device.h | 3 +++ > > 2 files changed, 26 insertions(+) > > > >diff --git a/drivers/base/platform.c b/drivers/base/platform.c > >index 6482d47..3ef150d 100644 > >--- a/drivers/base/platform.c > >+++ b/drivers/base/platform.c > >@@ -760,6 +760,29 @@ err_out: > > } > > EXPORT_SYMBOL_GPL(__platform_create_bundle); > > > >+static int fwnode_dev_match(struct device *dev, void *data) > >+{ > >+ return dev->fwnode == data; > >+} > >+ > >+/** > >+ * platform_find_device_by_fwnode() - Find the platform_device associated > >+ * with a fwnode > >+ * @fwnode: Pointer to firmware node > >+ * > >+ * Returns platform_device pointer, or NULL if not found > >+ */ > >+struct platform_device * > >+platform_find_device_by_fwnode(struct fwnode_handle *fwnode) > >+{ > >+ struct device *dev; > >+ > >+ dev = bus_find_device(&platform_bus_type, NULL, fwnode, > >+ fwnode_dev_match); > >+ return dev ? to_platform_device(dev) : NULL; > >+} > >+EXPORT_SYMBOL(platform_find_device_by_fwnode); > > As SMMU is registered as platform devices, I think we need such > API to retrieve the platform device with fwnode handle, actually > Kefeng introduced a similar patch [1], but your patch is more > generic, so this patch make sense to me, > > Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Thanks ! Strictly speaking, with Robin's new series: https://lists.linuxfoundation.org/pipermail/iommu/2016-August/018230.html (and corresponding v5 of this one that I have rebased on top of it) we do not need this patch any longer and it is not really that generic keeping in mind that it can't be used for DT matching (because in DT dev->fwnode is dangling); I will see if I keep this patch according to dependencies. Side note: I have a problem with [1], since that code is there to implement DT phandles in ACPI IIUC and we must really prevent that :) Thanks ! Lorenzo > Thanks > Hanjun > > [1]: https://patchwork.kernel.org/patch/7743661/ >
On 2016/9/5 22:57, Lorenzo Pieralisi wrote: > On Mon, Sep 05, 2016 at 09:19:43PM +0800, Hanjun Guo wrote: >> On 2016/8/15 23:23, Lorenzo Pieralisi wrote: >>> The platform device kernel API does not provide functions to >>> retrieve a platform device through the corresponding struct >>> device fwnode pointer. >>> >>> Implement the fwnode platform_device look-up in drivers core >>> code by using the bus_find_device() API and a corresponding >>> matching function. The OF equivalent (eg of_find_device_by_node()) >>> will reuse the newly introduced function when OF code will >>> take care of setting up the device->fwnode value that is >>> currently left dangling for platform devices instantiated out >>> of device tree nodes. >>> >>> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> >>> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >>> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> >>> --- >>> drivers/base/platform.c | 23 +++++++++++++++++++++++ >>> include/linux/platform_device.h | 3 +++ >>> 2 files changed, 26 insertions(+) >>> >>> diff --git a/drivers/base/platform.c b/drivers/base/platform.c >>> index 6482d47..3ef150d 100644 >>> --- a/drivers/base/platform.c >>> +++ b/drivers/base/platform.c >>> @@ -760,6 +760,29 @@ err_out: >>> } >>> EXPORT_SYMBOL_GPL(__platform_create_bundle); >>> >>> +static int fwnode_dev_match(struct device *dev, void *data) >>> +{ >>> + return dev->fwnode == data; >>> +} >>> + >>> +/** >>> + * platform_find_device_by_fwnode() - Find the platform_device associated >>> + * with a fwnode >>> + * @fwnode: Pointer to firmware node >>> + * >>> + * Returns platform_device pointer, or NULL if not found >>> + */ >>> +struct platform_device * >>> +platform_find_device_by_fwnode(struct fwnode_handle *fwnode) >>> +{ >>> + struct device *dev; >>> + >>> + dev = bus_find_device(&platform_bus_type, NULL, fwnode, >>> + fwnode_dev_match); >>> + return dev ? to_platform_device(dev) : NULL; >>> +} >>> +EXPORT_SYMBOL(platform_find_device_by_fwnode); >> >> As SMMU is registered as platform devices, I think we need such >> API to retrieve the platform device with fwnode handle, actually >> Kefeng introduced a similar patch [1], but your patch is more >> generic, so this patch make sense to me, >> >> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> > > Thanks ! Strictly speaking, with Robin's new series: > > https://lists.linuxfoundation.org/pipermail/iommu/2016-August/018230.html > > > (and corresponding v5 of this one that I have rebased on top of it) we > do not need this patch any longer and it is not really that generic > keeping in mind that it can't be used for DT matching (because in DT > dev->fwnode is dangling); I will see if I keep this patch according > to dependencies. OK, I think I will wait for your new version, then try another test and review it, does it make sense? > > Side note: I have a problem with [1], since that code is there to > implement DT phandles in ACPI IIUC and we must really prevent that :) Agreed :) Thanks Hanjun
diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 6482d47..3ef150d 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -760,6 +760,29 @@ err_out: } EXPORT_SYMBOL_GPL(__platform_create_bundle); +static int fwnode_dev_match(struct device *dev, void *data) +{ + return dev->fwnode == data; +} + +/** + * platform_find_device_by_fwnode() - Find the platform_device associated + * with a fwnode + * @fwnode: Pointer to firmware node + * + * Returns platform_device pointer, or NULL if not found + */ +struct platform_device * +platform_find_device_by_fwnode(struct fwnode_handle *fwnode) +{ + struct device *dev; + + dev = bus_find_device(&platform_bus_type, NULL, fwnode, + fwnode_dev_match); + return dev ? to_platform_device(dev) : NULL; +} +EXPORT_SYMBOL(platform_find_device_by_fwnode); + /** * __platform_register_drivers - register an array of platform drivers * @drivers: an array of drivers to register diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 98c2a7c..01a3eb2 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -276,6 +276,9 @@ extern struct platform_device *__platform_create_bundle( struct resource *res, unsigned int n_res, const void *data, size_t size, struct module *module); +extern struct platform_device * +platform_find_device_by_fwnode(struct fwnode_handle *fwnode); + int __platform_register_drivers(struct platform_driver * const *drivers, unsigned int count, struct module *owner); void platform_unregister_drivers(struct platform_driver * const *drivers,
The platform device kernel API does not provide functions to retrieve a platform device through the corresponding struct device fwnode pointer. Implement the fwnode platform_device look-up in drivers core code by using the bus_find_device() API and a corresponding matching function. The OF equivalent (eg of_find_device_by_node()) will reuse the newly introduced function when OF code will take care of setting up the device->fwnode value that is currently left dangling for platform devices instantiated out of device tree nodes. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> --- drivers/base/platform.c | 23 +++++++++++++++++++++++ include/linux/platform_device.h | 3 +++ 2 files changed, 26 insertions(+)