[0/5] Raspberry Pi SPI unbind fixes

Message

Lukas Wunner May 15, 2020, 3:58 p.m. UTC

This series fixes ordering issues occurring on unbind of the
Raspberry Pi SPI drivers:

Turns out devm_spi_register_controller() is prone to
incorrect use and dozens of drivers have gotten it wrong.
I'm only documenting this gotcha here and fixing it in the
Raspberry Pi drivers.  Fixing the rest is for another day.

There's also an ordering issue in the core which has been
present for 8 years and affects all platforms (patch [1/5]).
Doesn't look like unbinding is tested all that often. :-)


Lukas Wunner (5):
  spi: Fix controller unregister order
  spi: bcm2835: Fix controller unregister order
  spi: bcm2835aux: Fix controller unregister order
  spi: bcm2835: Tear down DMA before turning off SPI controller
  spi: Document devm_spi_register_controller() gotcha

 drivers/spi/spi-bcm2835.c    |  8 +++++---
 drivers/spi/spi-bcm2835aux.c |  4 +++-
 drivers/spi/spi.c            | 10 +++++++++-
 3 files changed, 17 insertions(+), 5 deletions(-)

Comments

Mark Brown May 20, 2020, 5:17 p.m. UTC | #1

On Fri, 15 May 2020 17:58:00 +0200, Lukas Wunner wrote:
> This series fixes ordering issues occurring on unbind of the
> Raspberry Pi SPI drivers:
> 
> Turns out devm_spi_register_controller() is prone to
> incorrect use and dozens of drivers have gotten it wrong.
> I'm only documenting this gotcha here and fixing it in the
> Raspberry Pi drivers.  Fixing the rest is for another day.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/4] spi: Fix controller unregister order
      commit: 84855678add8aba927faf76bc2f130a40f94b6f7
[2/4] spi: bcm2835: Fix controller unregister order
      commit: 9dd277ff92d06f6aa95b39936ad83981d781f49b
[3/4] spi: bcm2835aux: Fix controller unregister order
      commit: b9dd3f6d417258ad0beeb292a1bc74200149f15d
[4/4] spi: bcm2835: Tear down DMA before turning off SPI controller
      (no commit info)

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