| Message ID | 20230310222857.315629-1-krzysztof.kozlowski@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [01/16] spi: armada-3700: Drop of_match_ptr for ID table | expand |
On Fri, Mar 10, 2023 at 11:28:42PM +0100, Krzysztof Kozlowski wrote: > The driver can match only via the DT table so the table should be always > used and the of_match_ptr does not have any sense (this also allows ACPI > matching via PRP0001, even though it is not relevant here). > > drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] It would be much better to fix of_match_ptr() and/or the module stuff that also references the match table here.
On Fri, 10 Mar 2023 23:28:42 +0100, Krzysztof Kozlowski wrote: > The driver can match only via the DT table so the table should be always > used and the of_match_ptr does not have any sense (this also allows ACPI > matching via PRP0001, even though it is not relevant here). > > drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] > > > [...] Applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next Thanks! [12/16] spi: pxa2xx: Mark OF related data as maybe unused commit: d94df25e8b9c8deefc5d7fcd344eb5d4bd41cf7b [13/16] spi: bcm-qspi: Mark OF related data as maybe unused commit: 6340fdf2e13c5f1ff3a9622f0cb3b8e9c3955a31 [14/16] spi: sh-msiof: Mark OF related data as maybe unused commit: d946b6b0ed01949b1a3856e03469361fc9168318 [15/16] spi: sc18is602: Mark OF related data as maybe unused commit: 833f43308234600e934e9c6fa70fd8b7eebc632b [16/16] spi: rspi: Mark OF related data as maybe unused commit: edfa970370a759c2c6a38b2884887937b1aea552 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark
On 13/03/2023 14:55, Mark Brown wrote: > On Fri, Mar 10, 2023 at 11:28:42PM +0100, Krzysztof Kozlowski wrote: >> The driver can match only via the DT table so the table should be always >> used and the of_match_ptr does not have any sense (this also allows ACPI >> matching via PRP0001, even though it is not relevant here). >> >> drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] > > It would be much better to fix of_match_ptr() and/or the module stuff > that also references the match table here. Why? The recommendation is in general not to use of_match_ptr, because there are little benefits but it disables matching via PRP0001. Jonathan in parallel thread explicitly said of_match_ptr should disappear and he is not accepting any new code with it. And in general he is right. https://lore.kernel.org/all/20230311183534.1d0dfd64@jic23-huawei/ and earlier: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=444f5f854b35 Best regards, Krzysztof
On Mon, Mar 13, 2023 at 07:39:45PM +0100, Krzysztof Kozlowski wrote: > On 13/03/2023 14:55, Mark Brown wrote: > > On Fri, Mar 10, 2023 at 11:28:42PM +0100, Krzysztof Kozlowski wrote: > >> drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] > > It would be much better to fix of_match_ptr() and/or the module stuff > > that also references the match table here. > Why? The recommendation is in general not to use of_match_ptr, because > there are little benefits but it disables matching via PRP0001. Jonathan > in parallel thread explicitly said of_match_ptr should disappear and he > is not accepting any new code with it. And in general he is right. If that's the case then why are you adding maybe unused annotations for half the drivers rather than removing their of_match_ptr() usages? There doesn't seem to be any logic here, it's just randomly making changes as far as I can tell. The PRP0001 stuff isn't an issue, of_match_ptr() can just be changed to do the right thing for CONFIG_ACPI. It doesn't buy us huge amounts but it also costs us very little and may be useful in future. When there's missing annotations it's not causing issues for practical configurations as far as I can tell, and if the macro were updated for CONFIG_ACPI it'd be even less of an issue.
On 13/03/2023 20:22, Mark Brown wrote: > On Mon, Mar 13, 2023 at 07:39:45PM +0100, Krzysztof Kozlowski wrote: >> On 13/03/2023 14:55, Mark Brown wrote: >>> On Fri, Mar 10, 2023 at 11:28:42PM +0100, Krzysztof Kozlowski wrote: > >>>> drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] > >>> It would be much better to fix of_match_ptr() and/or the module stuff >>> that also references the match table here. > >> Why? The recommendation is in general not to use of_match_ptr, because >> there are little benefits but it disables matching via PRP0001. Jonathan >> in parallel thread explicitly said of_match_ptr should disappear and he >> is not accepting any new code with it. And in general he is right. > > If that's the case then why are you adding maybe unused annotations for > half the drivers rather than removing their of_match_ptr() usages? > There doesn't seem to be any logic here, it's just randomly making > changes as far as I can tell. These are not random but depend on whether OF is the only matching method or one of few. Although for IIO all of my patches would be dropping the of_match_ptr... For some cases in other patchsets I added __maybe_unused also because of_match_node(), when the table is not used in driver of_match_table. > > The PRP0001 stuff isn't an issue, of_match_ptr() can just be changed to > do the right thing for CONFIG_ACPI. That's actually interesting idea, kind of obvious so I wonder why it wasn't done like this in the first place in 886ca88be6b3 ("ACPI / bus: Respect PRP0001 when retrieving device match data"). Maybe not to populate OF device ID tables for the ACPI systems which do not care about PRP0001? > It doesn't buy us huge amounts but > it also costs us very little and may be useful in future. When there's > missing annotations it's not causing issues for practical configurations > as far as I can tell, and if the macro were updated for CONFIG_ACPI it'd > be even less of an issue. Best regards, Krzysztof
On Tue, Mar 14, 2023 at 07:44:04AM +0100, Krzysztof Kozlowski wrote: > On 13/03/2023 20:22, Mark Brown wrote: > > If that's the case then why are you adding maybe unused annotations for > > half the drivers rather than removing their of_match_ptr() usages? > > There doesn't seem to be any logic here, it's just randomly making > > changes as far as I can tell. > These are not random but depend on whether OF is the only matching > method or one of few. Although for IIO all of my patches would be > dropping the of_match_ptr... For some cases in other patchsets I added > __maybe_unused also because of_match_node(), when the table is not used > in driver of_match_table. This logic is both not apparent when looking at the patches and doesn't move us in any particular direction - I'd expect this stuff to be written the same way for all drivers, there's no reason for it to vary. That just adds complication, it's more random obscure rules people have to learn. > > The PRP0001 stuff isn't an issue, of_match_ptr() can just be changed to > > do the right thing for CONFIG_ACPI. > That's actually interesting idea, kind of obvious so I wonder why it > wasn't done like this in the first place in 886ca88be6b3 ("ACPI / bus: > Respect PRP0001 when retrieving device match data"). Maybe not to > populate OF device ID tables for the ACPI systems which do not care > about PRP0001? Or just it didn't occur to anyone at the time.
diff --git a/drivers/spi/spi-armada-3700.c b/drivers/spi/spi-armada-3700.c index 6a7e605f73bf..feb7371940bc 100644 --- a/drivers/spi/spi-armada-3700.c +++ b/drivers/spi/spi-armada-3700.c @@ -919,7 +919,7 @@ static void a3700_spi_remove(struct platform_device *pdev) static struct platform_driver a3700_spi_driver = { .driver = { .name = DRIVER_NAME, - .of_match_table = of_match_ptr(a3700_spi_dt_ids), + .of_match_table = a3700_spi_dt_ids, }, .probe = a3700_spi_probe, .remove_new = a3700_spi_remove,
The driver can match only via the DT table so the table should be always used and the of_match_ptr does not have any sense (this also allows ACPI matching via PRP0001, even though it is not relevant here). drivers/spi/spi-armada-3700.c:807:34: error: ‘a3700_spi_dt_ids’ defined but not used [-Werror=unused-const-variable=] Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> --- drivers/spi/spi-armada-3700.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)