| Message ID | 20240211174237.182947-1-jic23@kernel.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | of: automate of_node_put() - new approach to loops. | expand |
On Sun, Feb 11, 2024 at 05:42:28PM +0000, Jonathan Cameron wrote: > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > Since RFC: > - Provide a for_each_available_child_of_node_scoped() variant and > use that whenever we aren't specifically trying to include disabled > nodes. > - Fix the for_each_child_of_node_scoped() to not use a mix of > _available_ and other calls. > - Include a few more examples. The last one is there to show that > not all uses of the __free(device_node) call are due to the loops. I'm a bit skeptical about need of this work. What I would prefer to see is getting rid of OF-centric drivers in IIO. With that, we would need only fwnode part to be properly implemented.
On Mon, 12 Feb 2024 14:03:29 +0200 Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > On Sun, Feb 11, 2024 at 05:42:28PM +0000, Jonathan Cameron wrote: > > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > > Since RFC: > > - Provide a for_each_available_child_of_node_scoped() variant and > > use that whenever we aren't specifically trying to include disabled > > nodes. > > - Fix the for_each_child_of_node_scoped() to not use a mix of > > _available_ and other calls. > > - Include a few more examples. The last one is there to show that > > not all uses of the __free(device_node) call are due to the loops. > > I'm a bit skeptical about need of this work. What I would prefer to see > is getting rid of OF-centric drivers in IIO. With that, we would need > only fwnode part to be properly implemented. > To be honest main reason for doing of first was that they have unit tests :) The IIO drivers were more of a proving ground than cases I really cared out cleaning up. However I'm always of the view that better to make some improvement now than wait for a perfect improvement later. However one or two are not going to be converted to fwnode handling any time soon because they make use of phandle based referencing for driver specific hook ups that isn't going to get generic handling any time soon. I'll probably focus on getting the fwnode version of this moving forwards first though and 'maybe' convert a few of the easier ones of these over to that framework to reduce how many users of this we end up with in IIO. Jonathan
On Fri, Feb 16, 2024 at 02:47:56PM +0000, Jonathan Cameron wrote: > On Mon, 12 Feb 2024 14:03:29 +0200 > Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > > On Sun, Feb 11, 2024 at 05:42:28PM +0000, Jonathan Cameron wrote: ... > > I'm a bit skeptical about need of this work. What I would prefer to see > > is getting rid of OF-centric drivers in IIO. With that, we would need > > only fwnode part to be properly implemented. > > To be honest main reason for doing of first was that they have unit tests :) fwnode also has KUnit test. Have you considered adding test cases there? > The IIO drivers were more of a proving ground than cases I really cared > out cleaning up. However I'm always of the view that better to make > some improvement now than wait for a perfect improvement later. Yes, but in my opinion _in this particular case_ it brings more churn and some maybe even not good from educational purposes, i.e. one can look at the current series and think "oh, OF is still in use, let me provide my driver OF-only (for whatever reasons behind)", while targeting conversion first will tell people: "hey, there is an agnostic device property framework that should be used in a new code and that's why we have been converting old drivers too". > However one or two are not going to be converted to fwnode handling > any time soon because they make use of phandle based referencing for > driver specific hook ups that isn't going to get generic handling any > time soon. Sure, exceptions happen. > I'll probably focus on getting the fwnode version of this moving > forwards first though and 'maybe' convert a few of the easier ones > of these over to that framework to reduce how many users of this > we end up with in IIO. Thanks!
On Fri, 16 Feb 2024 17:25:45 +0200 Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > On Fri, Feb 16, 2024 at 02:47:56PM +0000, Jonathan Cameron wrote: > > On Mon, 12 Feb 2024 14:03:29 +0200 > > Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote: > > > On Sun, Feb 11, 2024 at 05:42:28PM +0000, Jonathan Cameron wrote: > > ... > > > > I'm a bit skeptical about need of this work. What I would prefer to see > > > is getting rid of OF-centric drivers in IIO. With that, we would need > > > only fwnode part to be properly implemented. > > > > To be honest main reason for doing of first was that they have unit tests :) > > fwnode also has KUnit test. Have you considered adding test cases there? > > > The IIO drivers were more of a proving ground than cases I really cared > > out cleaning up. However I'm always of the view that better to make > > some improvement now than wait for a perfect improvement later. > > Yes, but in my opinion _in this particular case_ it brings more churn and > some maybe even not good from educational purposes, i.e. one can look at > the current series and think "oh, OF is still in use, let me provide my > driver OF-only (for whatever reasons behind)", while targeting conversion > first will tell people: "hey, there is an agnostic device property framework > that should be used in a new code and that's why we have been converting old > drivers too". > > > However one or two are not going to be converted to fwnode handling > > any time soon because they make use of phandle based referencing for > > driver specific hook ups that isn't going to get generic handling any > > time soon. > > Sure, exceptions happen. After the series converting over most of the cases this patch set touched in IIO, I have rcar-gyroadc and the unit test left, which are enough to show the purpose of the patch and put a few real users in place. Will submit a v2 with just those 2 users. Ideal would be to get these in for the merge window so it is available for other subsystems next cycle. > > > I'll probably focus on getting the fwnode version of this moving > > forwards first though and 'maybe' convert a few of the easier ones > > of these over to that framework to reduce how many users of this > > we end up with in IIO. > > Thanks! >
From: Jonathan Cameron <Jonathan.Cameron@huawei.com> Since RFC: - Provide a for_each_available_child_of_node_scoped() variant and use that whenever we aren't specifically trying to include disabled nodes. - Fix the for_each_child_of_node_scoped() to not use a mix of _available_ and other calls. - Include a few more examples. The last one is there to show that not all uses of the __free(device_node) call are due to the loops. Thanks to Julia Lawal who also posted coccinelle for both types (loop and non loop cases) https://lore.kernel.org/all/alpine.DEB.2.22.394.2401312234250.3245@hadrien/ https://lore.kernel.org/all/alpine.DEB.2.22.394.2401291455430.8649@hadrien/ The cover letter of the RFC includes information on the various approaches considered. https://lore.kernel.org/all/20240128160542.178315-1-jic23@kernel.org/ Whilst these macros profduce nice reductions in complexity the loops still have the unfortunate side effect of hiding the local declaration of a struct device_node * which is then used inside the loop. Julia suggested making that a little more visible via #define for_each_child_of_node_scoped(parent, struct device_node *, child) but in discussion we both expressed that this doesn't really make things all that clear either so I haven't adopted this suggestion. If the responses to this series are positive I can put the first few patches on an immutable branch, allowing rapid adoption in other trees if people want to move quickly. If not we can wait for next cycle and just take this infrastructure through the IIO tree ready for the 6.9 merge cycle. I'll be optimistic that we are converging and send out an equivalent series for fwnode_handle / property.h to replace the previous proposal: https://lore.kernel.org/all/20240114172009.179893-1-jic23@kernel.org/ Jonathan Cameron (8): of: Add cleanup.h based auto release via __free(device_node) markings. of: Introduce for_each_*_child_of_node_scoped() to automate of_node_put() handling of: unittest: Use for_each_child_of_node_scoped() iio: adc: fsl-imx25-gcq: Use for_each_available_child_node_scoped() iio: adc: rcar-gyroadc: use for_each_available_child_node_scoped() iio: adc: ad7124: Use for_each_available_child_of_node_scoped() iio: adc: ad7292: Use for_each_available_child_of_node_scoped() iio: adc: adi-axi-adc: Use __free(device_node) and guard(mutex) drivers/iio/adc/ad7124.c | 20 ++++++-------------- drivers/iio/adc/ad7292.c | 7 ++----- drivers/iio/adc/adi-axi-adc.c | 16 ++++------------ drivers/iio/adc/fsl-imx25-gcq.c | 13 +++---------- drivers/iio/adc/rcar-gyroadc.c | 21 ++++++--------------- drivers/of/unittest.c | 11 +++-------- include/linux/of.h | 15 +++++++++++++++ 7 files changed, 39 insertions(+), 64 deletions(-)