| Message ID | 20210921192149.50740-1-broonie@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 5fa6863ba69265cb7e45567d12614790ff26bd56 |
| Headers | show |
| Series | spi: Check we have a spi_device_id for each DT compatible | expand |
On Tue, 21 Sep 2021 20:21:49 +0100, Mark Brown wrote: > Currently for SPI devices we use the spi_device_id for module autoloading > even on systems using device tree, meaning that listing a compatible string > in the of_match_table isn't enough to have the module for a SPI driver > autoloaded. > > We attempted to fix this by generating OF based modaliases for devices > instantiated from DT in 3ce6c9e2617e ("spi: add of_device_uevent_modalias > support") but this meant we no longer reported spi_device_id based aliases > which broke drivers such as spi-nor which don't list all the compatible > strings they support directly for DT, and in at least that case it's not > super practical to do so given the very large number of compatibles > needed, much larger than the number spi_device_ids due to vendor strings. > As a result fell back to using spi_device_id based modalises. > > [...] Applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator.git for-next Thanks! [1/1] spi: Check we have a spi_device_id for each DT compatible commit: 5fa6863ba69265cb7e45567d12614790ff26bd56 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
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 57e2499ec1ed..2c7f420b9f73 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -459,6 +459,47 @@ int __spi_register_driver(struct module *owner, struct spi_driver *sdrv) { sdrv->driver.owner = owner; sdrv->driver.bus = &spi_bus_type; + + /* + * For Really Good Reasons we use spi: modaliases not of: + * modaliases for DT so module autoloading won't work if we + * don't have a spi_device_id as well as a compatible string. + */ + if (sdrv->driver.of_match_table) { + const struct of_device_id *of_id; + + for (of_id = sdrv->driver.of_match_table; of_id->compatible[0]; + of_id++) { + const char *of_name; + + /* Strip off any vendor prefix */ + of_name = strnchr(of_id->compatible, + sizeof(of_id->compatible), ','); + if (of_name) + of_name++; + else + of_name = of_id->compatible; + + if (sdrv->id_table) { + const struct spi_device_id *spi_id; + + for (spi_id = sdrv->id_table; spi_id->name[0]; + spi_id++) + if (strcmp(spi_id->name, of_name) == 0) + break; + + if (spi_id->name[0]) + continue; + } else { + if (strcmp(sdrv->driver.name, of_name) == 0) + continue; + } + + pr_warn("SPI driver %s has no spi_device_id for %s\n", + sdrv->driver.name, of_id->compatible); + } + } + return driver_register(&sdrv->driver); } EXPORT_SYMBOL_GPL(__spi_register_driver);
Currently for SPI devices we use the spi_device_id for module autoloading even on systems using device tree, meaning that listing a compatible string in the of_match_table isn't enough to have the module for a SPI driver autoloaded. We attempted to fix this by generating OF based modaliases for devices instantiated from DT in 3ce6c9e2617e ("spi: add of_device_uevent_modalias support") but this meant we no longer reported spi_device_id based aliases which broke drivers such as spi-nor which don't list all the compatible strings they support directly for DT, and in at least that case it's not super practical to do so given the very large number of compatibles needed, much larger than the number spi_device_ids due to vendor strings. As a result fell back to using spi_device_id based modalises. Try to close the gap by printing a warning when a SPI driver has a DT compatible that won't be matched as a SPI device ID with the goal of having drivers provide both. Given fallback compatibles this check is going to be excessive but it should be robust which is probably more important here. Signed-off-by: Mark Brown <broonie@kernel.org> --- drivers/spi/spi.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+)