[PATCH 00/14] mtd: Fix platform remove callbacks to always return 0

[PATCH 00/14] mtd: Fix platform remove callbacks to always return 0

[Uwe Kleine-König]

Hello,

this series prepares to make platform remove callbacks return void.
Therefor first update them to always return 0. The rationale is that the
Linux device model doesn't handle failures on remove and if a remove
callback returns an error, it just emits a quite generic error message
and still removes the device.

Best regards
Uwe

Uwe Kleine-König (14):
  mtd: hyperbus: Make hyperbus_unregister_device() return void
  mtd: spi-nor: aspeed-smc: Make aspeed_smc_unregister() return void
  mtd: powernv_flash: Warn about failure to unregister mtd device
  mtd: st-spi_fsm: Warn about failure to unregister mtd device
  mtd: lpddr2_nvm: Warn about failure to unregister mtd device
  mtd: spear_smi: Don't skip cleanup after mtd_device_unregister()
    failed
  mtd: spear_smi: Drop if with an always false condition
  mtd: rawnand: atmel: Warn about failure to unregister mtd device
  mtd: rawnand: omap2: Suppress error message after WARN in .remove()
  mtd: rawnand: tegra: Don't skip cleanup after mtd_device_unregister()
    failed
  mtd: rawnand: meson: Don't skip cleanup after mtd_device_unregister()
    failed
  mtd: rawnand: meson: Drop cleaning platform data in .remove()
  mtd: physmap: Don't skip cleanup after mtd_device_unregister() failed
  mtd: physmap: Drop if with an always false condition

 drivers/mtd/devices/powernv_flash.c          |  4 +++-
 drivers/mtd/devices/spear_smi.c              | 10 ++--------
 drivers/mtd/devices/st_spi_fsm.c             |  4 +++-
 drivers/mtd/hyperbus/hbmc-am654.c            |  6 +++---
 drivers/mtd/hyperbus/hyperbus-core.c         |  8 ++------
 drivers/mtd/hyperbus/rpc-if.c                |  5 +++--
 drivers/mtd/lpddr/lpddr2_nvm.c               |  4 +++-
 drivers/mtd/maps/physmap-core.c              | 13 +++----------
 drivers/mtd/nand/raw/atmel/nand-controller.c |  5 ++++-
 drivers/mtd/nand/raw/meson_nand.c            | 16 +++-------------
 drivers/mtd/nand/raw/omap2.c                 |  6 ++----
 drivers/mtd/nand/raw/tegra_nand.c            |  5 +----
 drivers/mtd/spi-nor/controllers/aspeed-smc.c |  8 ++++----
 include/linux/mtd/hyperbus.h                 |  4 +---
 14 files changed, 37 insertions(+), 61 deletions(-)

base-commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f
-- 
2.36.1

[PATCH 10/14] mtd: rawnand: tegra: Don't skip cleanup after mtd_device_unregister() failed

[Uwe Kleine-König]

If mtd_device_unregister() fails (which it doesn't when used correctly),
the resources bound by the nand chip should be freed anyhow as returning
an error value doesn't prevent the device getting unbound.

Instead use WARN_ON on the return value similar to how other drivers do
it.

This is a preparation for making platform remove callbacks return void.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/mtd/nand/raw/tegra_nand.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/mtd/nand/raw/tegra_nand.c b/drivers/mtd/nand/raw/tegra_nand.c
index b36e5260ae27..e12f9f580a15 100644
--- a/drivers/mtd/nand/raw/tegra_nand.c
+++ b/drivers/mtd/nand/raw/tegra_nand.c
@@ -1223,11 +1223,8 @@ static int tegra_nand_remove(struct platform_device *pdev)
 	struct tegra_nand_controller *ctrl = platform_get_drvdata(pdev);
 	struct nand_chip *chip = ctrl->chip;
 	struct mtd_info *mtd = nand_to_mtd(chip);
-	int ret;
 
-	ret = mtd_device_unregister(mtd);
-	if (ret)
-		return ret;
+	WARN_ON(mtd_device_unregister(mtd));
 
 	nand_cleanup(chip);
 
-- 
2.36.1

Re: [PATCH 00/14] mtd: Fix platform remove callbacks to always return 0

[Miquel Raynal]

Hi Folks,

u.kleine-koenig@pengutronix.de wrote on Fri,  3 Jun 2022 23:07:44 +0200:

> Hello,
> 
> this series prepares to make platform remove callbacks return void.
> Therefor first update them to always return 0. The rationale is that the
> Linux device model doesn't handle failures on remove and if a remove
> callback returns an error, it just emits a quite generic error message
> and still removes the device.

Tudor, Pratyush, Richard, Vignesh,

The series looks good to me (besides the atmel patch), I think it's
best to take it directly through mtd/next instead of going through all
the different internal branches, please let me know if you disagree
with the idea.

Cheers,
Miquèl

> 
> Best regards
> Uwe
> 
> Uwe Kleine-König (14):
>   mtd: hyperbus: Make hyperbus_unregister_device() return void
>   mtd: spi-nor: aspeed-smc: Make aspeed_smc_unregister() return void
>   mtd: powernv_flash: Warn about failure to unregister mtd device
>   mtd: st-spi_fsm: Warn about failure to unregister mtd device
>   mtd: lpddr2_nvm: Warn about failure to unregister mtd device
>   mtd: spear_smi: Don't skip cleanup after mtd_device_unregister()
>     failed
>   mtd: spear_smi: Drop if with an always false condition
>   mtd: rawnand: atmel: Warn about failure to unregister mtd device
>   mtd: rawnand: omap2: Suppress error message after WARN in .remove()
>   mtd: rawnand: tegra: Don't skip cleanup after mtd_device_unregister()
>     failed
>   mtd: rawnand: meson: Don't skip cleanup after mtd_device_unregister()
>     failed
>   mtd: rawnand: meson: Drop cleaning platform data in .remove()
>   mtd: physmap: Don't skip cleanup after mtd_device_unregister() failed
>   mtd: physmap: Drop if with an always false condition
> 
>  drivers/mtd/devices/powernv_flash.c          |  4 +++-
>  drivers/mtd/devices/spear_smi.c              | 10 ++--------
>  drivers/mtd/devices/st_spi_fsm.c             |  4 +++-
>  drivers/mtd/hyperbus/hbmc-am654.c            |  6 +++---
>  drivers/mtd/hyperbus/hyperbus-core.c         |  8 ++------
>  drivers/mtd/hyperbus/rpc-if.c                |  5 +++--
>  drivers/mtd/lpddr/lpddr2_nvm.c               |  4 +++-
>  drivers/mtd/maps/physmap-core.c              | 13 +++----------
>  drivers/mtd/nand/raw/atmel/nand-controller.c |  5 ++++-
>  drivers/mtd/nand/raw/meson_nand.c            | 16 +++-------------
>  drivers/mtd/nand/raw/omap2.c                 |  6 ++----
>  drivers/mtd/nand/raw/tegra_nand.c            |  5 +----
>  drivers/mtd/spi-nor/controllers/aspeed-smc.c |  8 ++++----
>  include/linux/mtd/hyperbus.h                 |  4 +---
>  14 files changed, 37 insertions(+), 61 deletions(-)
> 
> base-commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f

Re: [PATCH 00/14] mtd: Fix platform remove callbacks to always return 0

[Pratyush Yadav]

Hi Miquel,

On 06/06/22 03:18PM, Miquel Raynal wrote:
> Hi Folks,
> 
> u.kleine-koenig@pengutronix.de wrote on Fri,  3 Jun 2022 23:07:44 +0200:
> 
> > Hello,
> > 
> > this series prepares to make platform remove callbacks return void.
> > Therefor first update them to always return 0. The rationale is that the
> > Linux device model doesn't handle failures on remove and if a remove
> > callback returns an error, it just emits a quite generic error message
> > and still removes the device.
> 
> Tudor, Pratyush, Richard, Vignesh,
> 
> The series looks good to me (besides the atmel patch), I think it's
> best to take it directly through mtd/next instead of going through all
> the different internal branches, please let me know if you disagree
> with the idea.

Patch 2 does not look good to me. It modifies the aspeed-smc driver in 
drivers/mtd/spi-nor/controllers/ but the driver has been moved to 
drivers/spi/ in Mark's next branch [0]. The patch would likely conflict 
with that.

[0] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit?id=9c63b846e6df43e5b3d31263f7db545f32deeda3

> 
> Cheers,
> Miquèl
> 
> > 
> > Best regards
> > Uwe
> > 
> > Uwe Kleine-König (14):
> >   mtd: hyperbus: Make hyperbus_unregister_device() return void
> >   mtd: spi-nor: aspeed-smc: Make aspeed_smc_unregister() return void
> >   mtd: powernv_flash: Warn about failure to unregister mtd device
> >   mtd: st-spi_fsm: Warn about failure to unregister mtd device
> >   mtd: lpddr2_nvm: Warn about failure to unregister mtd device
> >   mtd: spear_smi: Don't skip cleanup after mtd_device_unregister()
> >     failed
> >   mtd: spear_smi: Drop if with an always false condition
> >   mtd: rawnand: atmel: Warn about failure to unregister mtd device
> >   mtd: rawnand: omap2: Suppress error message after WARN in .remove()
> >   mtd: rawnand: tegra: Don't skip cleanup after mtd_device_unregister()
> >     failed
> >   mtd: rawnand: meson: Don't skip cleanup after mtd_device_unregister()
> >     failed
> >   mtd: rawnand: meson: Drop cleaning platform data in .remove()
> >   mtd: physmap: Don't skip cleanup after mtd_device_unregister() failed
> >   mtd: physmap: Drop if with an always false condition
> > 
> >  drivers/mtd/devices/powernv_flash.c          |  4 +++-
> >  drivers/mtd/devices/spear_smi.c              | 10 ++--------
> >  drivers/mtd/devices/st_spi_fsm.c             |  4 +++-
> >  drivers/mtd/hyperbus/hbmc-am654.c            |  6 +++---
> >  drivers/mtd/hyperbus/hyperbus-core.c         |  8 ++------
> >  drivers/mtd/hyperbus/rpc-if.c                |  5 +++--
> >  drivers/mtd/lpddr/lpddr2_nvm.c               |  4 +++-
> >  drivers/mtd/maps/physmap-core.c              | 13 +++----------
> >  drivers/mtd/nand/raw/atmel/nand-controller.c |  5 ++++-
> >  drivers/mtd/nand/raw/meson_nand.c            | 16 +++-------------
> >  drivers/mtd/nand/raw/omap2.c                 |  6 ++----
> >  drivers/mtd/nand/raw/tegra_nand.c            |  5 +----
> >  drivers/mtd/spi-nor/controllers/aspeed-smc.c |  8 ++++----
> >  include/linux/mtd/hyperbus.h                 |  4 +---
> >  14 files changed, 37 insertions(+), 61 deletions(-)
> > 
> > base-commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f
> 

-- 
Regards,
Pratyush Yadav
Texas Instruments Inc.

Re: [PATCH 00/14] mtd: Fix platform remove callbacks to always return 0

[Miquel Raynal]

Hi Pratyush, Uwe,

p.yadav@ti.com wrote on Tue, 7 Jun 2022 15:02:36 +0530:

> Hi Miquel,
> 
> On 06/06/22 03:18PM, Miquel Raynal wrote:
> > Hi Folks,
> > 
> > u.kleine-koenig@pengutronix.de wrote on Fri,  3 Jun 2022 23:07:44 +0200:
> >   
> > > Hello,
> > > 
> > > this series prepares to make platform remove callbacks return void.
> > > Therefor first update them to always return 0. The rationale is that the
> > > Linux device model doesn't handle failures on remove and if a remove
> > > callback returns an error, it just emits a quite generic error message
> > > and still removes the device.  
> > 
> > Tudor, Pratyush, Richard, Vignesh,
> > 
> > The series looks good to me (besides the atmel patch), I think it's
> > best to take it directly through mtd/next instead of going through all
> > the different internal branches, please let me know if you disagree
> > with the idea.  
> 
> Patch 2 does not look good to me. It modifies the aspeed-smc driver in 
> drivers/mtd/spi-nor/controllers/ but the driver has been moved to 
> drivers/spi/ in Mark's next branch [0]. The patch would likely conflict 
> with that.
> 
> [0] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit?id=9c63b846e6df43e5b3d31263f7db545f32deeda3

Right, I believe Uwe is sending per-subsystems series so now that he is
aware we can safely drop patch 2.

Thanks,
Miquèl

Re: [PATCH 10/14] mtd: rawnand: tegra: Don't skip cleanup after mtd_device_unregister() failed

[Miquel Raynal]

On Fri, 2022-06-03 at 21:07:54 UTC, =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= wrote:
> If mtd_device_unregister() fails (which it doesn't when used correctly),
> the resources bound by the nand chip should be freed anyhow as returning
> an error value doesn't prevent the device getting unbound.
> 
> Instead use WARN_ON on the return value similar to how other drivers do
> it.
> 
> This is a preparation for making platform remove callbacks return void.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Applied to https://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next, thanks.

Miquel