[PATCH 00/18] remoteproc: Convert to platform remove callback returning void

[PATCH 00/18] remoteproc: Convert to platform remove callback returning void

[Uwe Kleine-König]

Hello,

this patch series adapts most platform drivers below drivers/remoteproc
to use the .remove_new() callback. Compared to the traditional .remove()
callback .remove_new() returns no value. This is a good thing because
the driver core doesn't (and cannot) cope for errors during remove. The
only effect of a non-zero return value in .remove() is that the driver
core emits a warning. The device is removed anyhow and an early return
from .remove() usually yields a resource leak. One driver suffering from
this problem (s3c2410) is fixed by the first patch.

By changing the remove callback to return void driver authors cannot
reasonably (but wrongly) assume any more that there happens some kind of
cleanup later.

There is one driver (i.e. ti_k3_dsp_remoteproc.c) that might return an
error code in .remove(). I didn't look in detail into this driver, but
if that error happens, we have exactly the bad situation described
above. (Note that kproc->mem and the register mapping goes away.)

Best regards
Uwe

Uwe Kleine-König (18):
  remoteproc: da8xx: Convert to platform remove callback returning void
  remoteproc: imx_dsp: Convert to platform remove callback returning
    void
  remoteproc: imx: Convert to platform remove callback returning void
  remoteproc: keystone: Convert to platform remove callback returning
    void
  remoteproc: meson_mx_ao_arc: Convert to platform remove callback
    returning void
  remoteproc: mtk_scp: Convert to platform remove callback returning
    void
  remoteproc: omap: Convert to platform remove callback returning void
  remoteproc: pru: Convert to platform remove callback returning void
  remoteproc: qcom_q6v5_adsp: Convert to platform remove callback
    returning void
  remoteproc: qcom_q6v5_mss: Convert to platform remove callback
    returning void
  remoteproc: qcom_q6v5_pas: Convert to platform remove callback
    returning void
  remoteproc: qcom_q6v5_wcss: Convert to platform remove callback
    returning void
  remoteproc: qcom_wcnss: Convert to platform remove callback returning
    void
  remoteproc: rcar: Convert to platform remove callback returning void
  remoteproc: virtio: Convert to platform remove callback returning void
  remoteproc: st: Convert to platform remove callback returning void
  remoteproc: stm32: Convert to platform remove callback returning void
  remoteproc: wkup_m3: Convert to platform remove callback returning
    void

 drivers/remoteproc/da8xx_remoteproc.c    | 6 ++----
 drivers/remoteproc/imx_dsp_rproc.c       | 6 ++----
 drivers/remoteproc/imx_rproc.c           | 6 ++----
 drivers/remoteproc/keystone_remoteproc.c | 6 ++----
 drivers/remoteproc/meson_mx_ao_arc.c     | 6 ++----
 drivers/remoteproc/mtk_scp.c             | 6 ++----
 drivers/remoteproc/omap_remoteproc.c     | 6 ++----
 drivers/remoteproc/pru_rproc.c           | 6 ++----
 drivers/remoteproc/qcom_q6v5_adsp.c      | 6 ++----
 drivers/remoteproc/qcom_q6v5_mss.c       | 6 ++----
 drivers/remoteproc/qcom_q6v5_pas.c       | 6 ++----
 drivers/remoteproc/qcom_q6v5_wcss.c      | 6 ++----
 drivers/remoteproc/qcom_wcnss.c          | 6 ++----
 drivers/remoteproc/rcar_rproc.c          | 6 ++----
 drivers/remoteproc/remoteproc_virtio.c   | 6 ++----
 drivers/remoteproc/st_remoteproc.c       | 6 ++----
 drivers/remoteproc/stm32_rproc.c         | 6 ++----
 drivers/remoteproc/wkup_m3_rproc.c       | 6 ++----
 18 files changed, 36 insertions(+), 72 deletions(-)


base-commit: 1a5304fecee523060f26e2778d9d8e33c0562df3
-- 
2.39.2

[PATCH 06/18] remoteproc: mtk_scp: Convert to platform remove callback returning void

[Uwe Kleine-König]

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/remoteproc/mtk_scp.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
index e1d93e63d7df..dcc94ee2458d 100644
--- a/drivers/remoteproc/mtk_scp.c
+++ b/drivers/remoteproc/mtk_scp.c
@@ -913,7 +913,7 @@ static int scp_probe(struct platform_device *pdev)
 	return ret;
 }
 
-static int scp_remove(struct platform_device *pdev)
+static void scp_remove(struct platform_device *pdev)
 {
 	struct mtk_scp *scp = platform_get_drvdata(pdev);
 	int i;
@@ -925,8 +925,6 @@ static int scp_remove(struct platform_device *pdev)
 	for (i = 0; i < SCP_IPI_MAX; i++)
 		mutex_destroy(&scp->ipi_desc[i].lock);
 	mutex_destroy(&scp->send_lock);
-
-	return 0;
 }
 
 static const struct mtk_scp_of_data mt8183_of_data = {
@@ -1003,7 +1001,7 @@ MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
 
 static struct platform_driver mtk_scp_driver = {
 	.probe = scp_probe,
-	.remove = scp_remove,
+	.remove_new = scp_remove,
 	.driver = {
 		.name = "mtk-scp",
 		.of_match_table = mtk_scp_of_match,
-- 
2.39.2

Re: [PATCH 06/18] remoteproc: mtk_scp: Convert to platform remove callback returning void

[AngeloGioacchino Del Regno]

Il 04/05/23 21:44, Uwe Kleine-König ha scritto:
> The .remove() callback for a platform driver returns an int which makes
> many driver authors wrongly assume it's possible to do error handling by
> returning an error code. However the value returned is (mostly) ignored
> and this typically results in resource leaks. To improve here there is a
> quest to make the remove callback return void. In the first step of this
> quest all drivers are converted to .remove_new() which already returns
> void.
> 
> Trivially convert this driver from always returning zero in the remove
> callback to the void returning variant.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

Re: [PATCH 06/18] remoteproc: mtk_scp: Convert to platform remove callback returning void

[Matthias Brugger]

On 04/05/2023 21:44, Uwe Kleine-König wrote:
> The .remove() callback for a platform driver returns an int which makes
> many driver authors wrongly assume it's possible to do error handling by
> returning an error code. However the value returned is (mostly) ignored
> and this typically results in resource leaks. To improve here there is a
> quest to make the remove callback return void. In the first step of this
> quest all drivers are converted to .remove_new() which already returns
> void.
> 
> Trivially convert this driver from always returning zero in the remove
> callback to the void returning variant.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>

> ---
>   drivers/remoteproc/mtk_scp.c | 6 ++----
>   1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/remoteproc/mtk_scp.c b/drivers/remoteproc/mtk_scp.c
> index e1d93e63d7df..dcc94ee2458d 100644
> --- a/drivers/remoteproc/mtk_scp.c
> +++ b/drivers/remoteproc/mtk_scp.c
> @@ -913,7 +913,7 @@ static int scp_probe(struct platform_device *pdev)
>   	return ret;
>   }
>   
> -static int scp_remove(struct platform_device *pdev)
> +static void scp_remove(struct platform_device *pdev)
>   {
>   	struct mtk_scp *scp = platform_get_drvdata(pdev);
>   	int i;
> @@ -925,8 +925,6 @@ static int scp_remove(struct platform_device *pdev)
>   	for (i = 0; i < SCP_IPI_MAX; i++)
>   		mutex_destroy(&scp->ipi_desc[i].lock);
>   	mutex_destroy(&scp->send_lock);
> -
> -	return 0;
>   }
>   
>   static const struct mtk_scp_of_data mt8183_of_data = {
> @@ -1003,7 +1001,7 @@ MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
>   
>   static struct platform_driver mtk_scp_driver = {
>   	.probe = scp_probe,
> -	.remove = scp_remove,
> +	.remove_new = scp_remove,
>   	.driver = {
>   		.name = "mtk-scp",
>   		.of_match_table = mtk_scp_of_match,

Re: [PATCH 00/18] remoteproc: Convert to platform remove callback returning void

[Mathieu Poirier]

On Thu, May 04, 2023 at 09:44:35PM +0200, Uwe Kleine-König wrote:
> Hello,
> 
> this patch series adapts most platform drivers below drivers/remoteproc
> to use the .remove_new() callback. Compared to the traditional .remove()
> callback .remove_new() returns no value. This is a good thing because
> the driver core doesn't (and cannot) cope for errors during remove. The
> only effect of a non-zero return value in .remove() is that the driver
> core emits a warning. The device is removed anyhow and an early return
> from .remove() usually yields a resource leak. One driver suffering from
> this problem (s3c2410) is fixed by the first patch.
> 
> By changing the remove callback to return void driver authors cannot
> reasonably (but wrongly) assume any more that there happens some kind of
> cleanup later.
> 
> There is one driver (i.e. ti_k3_dsp_remoteproc.c) that might return an
> error code in .remove(). I didn't look in detail into this driver, but
> if that error happens, we have exactly the bad situation described
> above. (Note that kproc->mem and the register mapping goes away.)
> 
> Best regards
> Uwe
> 
> Uwe Kleine-König (18):
>   remoteproc: da8xx: Convert to platform remove callback returning void
>   remoteproc: imx_dsp: Convert to platform remove callback returning
>     void
>   remoteproc: imx: Convert to platform remove callback returning void
>   remoteproc: keystone: Convert to platform remove callback returning
>     void
>   remoteproc: meson_mx_ao_arc: Convert to platform remove callback
>     returning void
>   remoteproc: mtk_scp: Convert to platform remove callback returning
>     void
>   remoteproc: omap: Convert to platform remove callback returning void
>   remoteproc: pru: Convert to platform remove callback returning void
>   remoteproc: qcom_q6v5_adsp: Convert to platform remove callback
>     returning void
>   remoteproc: qcom_q6v5_mss: Convert to platform remove callback
>     returning void
>   remoteproc: qcom_q6v5_pas: Convert to platform remove callback
>     returning void
>   remoteproc: qcom_q6v5_wcss: Convert to platform remove callback
>     returning void
>   remoteproc: qcom_wcnss: Convert to platform remove callback returning
>     void
>   remoteproc: rcar: Convert to platform remove callback returning void
>   remoteproc: virtio: Convert to platform remove callback returning void
>   remoteproc: st: Convert to platform remove callback returning void
>   remoteproc: stm32: Convert to platform remove callback returning void
>   remoteproc: wkup_m3: Convert to platform remove callback returning
>     void
> 
>  drivers/remoteproc/da8xx_remoteproc.c    | 6 ++----
>  drivers/remoteproc/imx_dsp_rproc.c       | 6 ++----
>  drivers/remoteproc/imx_rproc.c           | 6 ++----
>  drivers/remoteproc/keystone_remoteproc.c | 6 ++----
>  drivers/remoteproc/meson_mx_ao_arc.c     | 6 ++----
>  drivers/remoteproc/mtk_scp.c             | 6 ++----
>  drivers/remoteproc/omap_remoteproc.c     | 6 ++----
>  drivers/remoteproc/pru_rproc.c           | 6 ++----
>  drivers/remoteproc/qcom_q6v5_adsp.c      | 6 ++----
>  drivers/remoteproc/qcom_q6v5_mss.c       | 6 ++----
>  drivers/remoteproc/qcom_q6v5_pas.c       | 6 ++----
>  drivers/remoteproc/qcom_q6v5_wcss.c      | 6 ++----
>  drivers/remoteproc/qcom_wcnss.c          | 6 ++----
>  drivers/remoteproc/rcar_rproc.c          | 6 ++----
>  drivers/remoteproc/remoteproc_virtio.c   | 6 ++----
>  drivers/remoteproc/st_remoteproc.c       | 6 ++----
>  drivers/remoteproc/stm32_rproc.c         | 6 ++----
>  drivers/remoteproc/wkup_m3_rproc.c       | 6 ++----
>  18 files changed, 36 insertions(+), 72 deletions(-)
>

I have applied this set.

Thanks,
Mathieu

> 
> base-commit: 1a5304fecee523060f26e2778d9d8e33c0562df3
> -- 
> 2.39.2
>