[PATCH] spi: omap2-mcspi: Correctly handle devm_clk_get_optional() errors

[PATCH] spi: omap2-mcspi: Correctly handle devm_clk_get_optional() errors

[Mark Brown]

devm_clk_get_optional() returns NULL for missing clocks and a PTR_ERR()
if there is a clock but we fail to get it, but currently we only handle
the latter case and do so as though the clock was missing.  If we get an
error back we should handle that as an error since the clock exists but
we failed to get it, if we get NULL then the clock doesn't exist and we
should handle that.

Fixes: 4c6ac5446d06 ("spi: omap2-mcspi: Fix the IS_ERR() bug for devm_clk_get_optional_enabled()")
Reported-by: Lars Pedersen <lapeddk@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/spi-omap2-mcspi.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
index add6247d348190452918900b145c3c5a00e409b3..29c616e2c408cf26b150a853f789128d003db1f0 100644
--- a/drivers/spi/spi-omap2-mcspi.c
+++ b/drivers/spi/spi-omap2-mcspi.c
@@ -1561,10 +1561,15 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
 	}
 
 	mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
-	if (IS_ERR(mcspi->ref_clk))
-		mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
-	else
+	if (IS_ERR(mcspi->ref_clk)) {
+		status = PTR_ERR(mcspi->ref_clk);
+		dev_err_probe(&pdev->dev, status, "Failed to get ref_clk");
+		goto free_ctlr;
+	}
+	if (mcspi->ref_clk)
 		mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk);
+	else
+		mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
 	ctlr->max_speed_hz = mcspi->ref_clk_hz;
 	ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15;
 

---
base-commit: 9d89551994a430b50c4fffcb1e617a057fa76e20
change-id: 20250116-spi-fix-omap2-optional-84aa541869e6

Best regards,
-- 
Mark Brown <broonie@kernel.org>

Re: [PATCH] spi: omap2-mcspi: Correctly handle devm_clk_get_optional() errors

[Lars Pedersen]

On Fri, 17 Jan 2025 at 17:16, Mark Brown <broonie@kernel.org> wrote:
>
> devm_clk_get_optional() returns NULL for missing clocks and a PTR_ERR()
> if there is a clock but we fail to get it, but currently we only handle
> the latter case and do so as though the clock was missing.  If we get an
> error back we should handle that as an error since the clock exists but
> we failed to get it, if we get NULL then the clock doesn't exist and we
> should handle that.

Hi Mark.

I have now tested the patch on our board and everything now works as
expected. Thanks!

Tested-by: Lars Pedersen <lapeddk@gmail.com>
>
> Fixes: 4c6ac5446d06 ("spi: omap2-mcspi: Fix the IS_ERR() bug for devm_clk_get_optional_enabled()")
> Reported-by: Lars Pedersen <lapeddk@gmail.com>
> Signed-off-by: Mark Brown <broonie@kernel.org>
> ---
>  drivers/spi/spi-omap2-mcspi.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c
> index add6247d348190452918900b145c3c5a00e409b3..29c616e2c408cf26b150a853f789128d003db1f0 100644
> --- a/drivers/spi/spi-omap2-mcspi.c
> +++ b/drivers/spi/spi-omap2-mcspi.c
> @@ -1561,10 +1561,15 @@ static int omap2_mcspi_probe(struct platform_device *pdev)
>         }
>
>         mcspi->ref_clk = devm_clk_get_optional_enabled(&pdev->dev, NULL);
> -       if (IS_ERR(mcspi->ref_clk))
> -               mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
> -       else
> +       if (IS_ERR(mcspi->ref_clk)) {
> +               status = PTR_ERR(mcspi->ref_clk);
> +               dev_err_probe(&pdev->dev, status, "Failed to get ref_clk");
> +               goto free_ctlr;
> +       }
> +       if (mcspi->ref_clk)
>                 mcspi->ref_clk_hz = clk_get_rate(mcspi->ref_clk);
> +       else
> +               mcspi->ref_clk_hz = OMAP2_MCSPI_MAX_FREQ;
>         ctlr->max_speed_hz = mcspi->ref_clk_hz;
>         ctlr->min_speed_hz = mcspi->ref_clk_hz >> 15;
>
>
> ---
> base-commit: 9d89551994a430b50c4fffcb1e617a057fa76e20
> change-id: 20250116-spi-fix-omap2-optional-84aa541869e6
>
> Best regards,
> --
> Mark Brown <broonie@kernel.org>
>

Re: [PATCH] spi: omap2-mcspi: Correctly handle devm_clk_get_optional() errors

[Mark Brown]

On Fri, 17 Jan 2025 16:16:03 +0000, Mark Brown wrote:
> devm_clk_get_optional() returns NULL for missing clocks and a PTR_ERR()
> if there is a clock but we fail to get it, but currently we only handle
> the latter case and do so as though the clock was missing.  If we get an
> error back we should handle that as an error since the clock exists but
> we failed to get it, if we get NULL then the clock doesn't exist and we
> should handle that.
> 
> [...]

Applied to

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

Thanks!

[1/1] spi: omap2-mcspi: Correctly handle devm_clk_get_optional() errors
      commit: a07eb4f67ed085f32002a1af2b6073546d67de3f

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