| Message ID | cover.1661789204.git.christophe.leroy@csgroup.eu |
|---|---|
| Headers | show |
| Series | gpio: Get rid of ARCH_NR_GPIOS (v1) | expand |
On Mon, Aug 29, 2022 at 7:17 PM Christophe Leroy <christophe.leroy@csgroup.eu> wrote: > > Since commit 14e85c0e69d5 ("gpio: remove gpio_descs global array") > there is no limitation on the number of GPIOs that can be allocated > in the system since the allocation is fully dynamic. > > ARCH_NR_GPIOS is today only used in order to provide downwards > gpiobase allocation from that value, while static allocation is > performed upwards from 0. However that has the disadvantage of > limiting the number of GPIOs that can be registered in the system. > > To overcome this limitation without requiring each and every > platform to provide its 'best-guess' maximum number, rework the > allocation to allocate from 256 upwards, allowing approx 2 millions > of GPIOs. > > In the meantime, add a warning for drivers how are still doing > static allocation, so that in the future the static allocation gets > removed completely and dynamic allocation can start at base 0. For non-commented (by me or others) patches Reviewed-by: Andy Shevchenko <andy.shevchenko!gmail.com> For the patch 1 if you are going to address as suggested by the author of the driver, you may also add my tag. > Christophe Leroy (8): > gpio: aggregator: Stop using ARCH_NR_GPIOS > gpio: davinci: Stop using ARCH_NR_GPIOS > gpiolib: Warn on drivers still using static gpiobase allocation > gpiolib: Get rid of ARCH_NR_GPIOS > Documentation: gpio: Remove text about ARCH_NR_GPIOS > x86: Remove CONFIG_ARCH_NR_GPIO > arm: Remove CONFIG_ARCH_NR_GPIO > arm64: Remove CONFIG_ARCH_NR_GPIO > > Documentation/driver-api/gpio/legacy.rst | 5 --- > arch/arm/Kconfig | 21 --------- > arch/arm/include/asm/gpio.h | 1 - > arch/arm64/Kconfig | 12 ------ > arch/x86/Kconfig | 5 --- > drivers/gpio/gpio-aggregator.c | 8 ++-- > drivers/gpio/gpio-davinci.c | 3 -- > drivers/gpio/gpio-sta2x11.c | 5 +-- > drivers/gpio/gpiolib.c | 13 +++--- > include/asm-generic/gpio.h | 55 +++++++++--------------- > 10 files changed, 36 insertions(+), 92 deletions(-) > > -- > 2.37.1 >
On Tue, Aug 30, 2022 at 11:20 PM Andy Shevchenko <andy.shevchenko@gmail.com> wrote: > > On Mon, Aug 29, 2022 at 7:17 PM Christophe Leroy > <christophe.leroy@csgroup.eu> wrote: > > > > Since commit 14e85c0e69d5 ("gpio: remove gpio_descs global array") > > there is no limitation on the number of GPIOs that can be allocated > > in the system since the allocation is fully dynamic. > > > > ARCH_NR_GPIOS is today only used in order to provide downwards > > gpiobase allocation from that value, while static allocation is > > performed upwards from 0. However that has the disadvantage of > > limiting the number of GPIOs that can be registered in the system. > > > > To overcome this limitation without requiring each and every > > platform to provide its 'best-guess' maximum number, rework the > > allocation to allocate from 256 upwards, allowing approx 2 millions > > of GPIOs. > > > > In the meantime, add a warning for drivers how are still doing > > static allocation, so that in the future the static allocation gets > > removed completely and dynamic allocation can start at base 0. > > For non-commented (by me or others) patches > Reviewed-by: Andy Shevchenko <andy.shevchenko!gmail.com> Should be Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> > For the patch 1 if you are going to address as suggested by the author > of the driver, you may also add my tag.
Since commit 14e85c0e69d5 ("gpio: remove gpio_descs global array") there is no limitation on the number of GPIOs that can be allocated in the system since the allocation is fully dynamic. ARCH_NR_GPIOS is today only used in order to provide downwards gpiobase allocation from that value, while static allocation is performed upwards from 0. However that has the disadvantage of limiting the number of GPIOs that can be registered in the system. To overcome this limitation without requiring each and every platform to provide its 'best-guess' maximum number, rework the allocation to allocate from 256 upwards, allowing approx 2 millions of GPIOs. In the meantime, add a warning for drivers how are still doing static allocation, so that in the future the static allocation gets removed completely and dynamic allocation can start at base 0. Christophe Leroy (8): gpio: aggregator: Stop using ARCH_NR_GPIOS gpio: davinci: Stop using ARCH_NR_GPIOS gpiolib: Warn on drivers still using static gpiobase allocation gpiolib: Get rid of ARCH_NR_GPIOS Documentation: gpio: Remove text about ARCH_NR_GPIOS x86: Remove CONFIG_ARCH_NR_GPIO arm: Remove CONFIG_ARCH_NR_GPIO arm64: Remove CONFIG_ARCH_NR_GPIO Documentation/driver-api/gpio/legacy.rst | 5 --- arch/arm/Kconfig | 21 --------- arch/arm/include/asm/gpio.h | 1 - arch/arm64/Kconfig | 12 ------ arch/x86/Kconfig | 5 --- drivers/gpio/gpio-aggregator.c | 8 ++-- drivers/gpio/gpio-davinci.c | 3 -- drivers/gpio/gpio-sta2x11.c | 5 +-- drivers/gpio/gpiolib.c | 13 +++--- include/asm-generic/gpio.h | 55 +++++++++--------------- 10 files changed, 36 insertions(+), 92 deletions(-)