| Message ID | 20230919133207.1400430-58-u.kleine-koenig@pengutronix.de (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | cc99582d46b428ba4c2cb7ecd05df4569b02d1f4 |
| Headers | show |
| Series | dma: Convert to platform remove callback returning void | expand |
> -----Original Message----- > From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> > Sent: Tuesday, September 19, 2023 7:02 PM > To: Vinod Koul <vkoul@kernel.org> > Cc: Simek, Michal <michal.simek@amd.com>; Pandey, Radhey Shyam > <radhey.shyam.pandey@amd.com>; Rob Herring <robh@kernel.org>; Peter > Korsgaard <peter@korsgaard.com>; Liu Shixin <liushixin2@huawei.com>; > dmaengine@vger.kernel.org; linux-arm-kernel@lists.infradead.org; > kernel@pengutronix.de > Subject: [PATCH 57/59] dma: xilinx: xilinx_dma: Convert to platform remove > callback returning void > > 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 ignored (apart from > emitting a warning) 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. Eventually after all drivers are > converted, .remove_new() is renamed to .remove(). > > 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/dma/xilinx/xilinx_dma.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/dma/xilinx/xilinx_dma.c > b/drivers/dma/xilinx/xilinx_dma.c index 0a3b2e22f23d..0c363a1ed853 > 100644 > --- a/drivers/dma/xilinx/xilinx_dma.c > +++ b/drivers/dma/xilinx/xilinx_dma.c > @@ -3245,7 +3245,7 @@ static int xilinx_dma_probe(struct platform_device > *pdev) > * > * Return: Always '0' > */ Nit - kernel-doc return documentation needs to be updated. > -static int xilinx_dma_remove(struct platform_device *pdev) > +static void xilinx_dma_remove(struct platform_device *pdev) > { > struct xilinx_dma_device *xdev = platform_get_drvdata(pdev); > int i; > @@ -3259,8 +3259,6 @@ static int xilinx_dma_remove(struct > platform_device *pdev) > xilinx_dma_chan_remove(xdev->chan[i]); > > xdma_disable_allclks(xdev); > - > - return 0; > } > > static struct platform_driver xilinx_vdma_driver = { @@ -3269,7 +3267,7 > @@ static struct platform_driver xilinx_vdma_driver = { > .of_match_table = xilinx_dma_of_ids, > }, > .probe = xilinx_dma_probe, > - .remove = xilinx_dma_remove, > + .remove_new = xilinx_dma_remove, > }; > > module_platform_driver(xilinx_vdma_driver); > -- > 2.40.1
Hello, On Fri, Sep 22, 2023 at 11:36:50AM +0000, Pandey, Radhey Shyam wrote: > > -----Original Message----- > > From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> > > Sent: Tuesday, September 19, 2023 7:02 PM > > To: Vinod Koul <vkoul@kernel.org> > > Cc: Simek, Michal <michal.simek@amd.com>; Pandey, Radhey Shyam > > <radhey.shyam.pandey@amd.com>; Rob Herring <robh@kernel.org>; Peter > > Korsgaard <peter@korsgaard.com>; Liu Shixin <liushixin2@huawei.com>; > > dmaengine@vger.kernel.org; linux-arm-kernel@lists.infradead.org; > > kernel@pengutronix.de > > Subject: [PATCH 57/59] dma: xilinx: xilinx_dma: Convert to platform remove > > callback returning void > > > > 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 ignored (apart from > > emitting a warning) 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. Eventually after all drivers are > > converted, .remove_new() is renamed to .remove(). > > > > 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/dma/xilinx/xilinx_dma.c | 6 ++---- > > 1 file changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/dma/xilinx/xilinx_dma.c > > b/drivers/dma/xilinx/xilinx_dma.c index 0a3b2e22f23d..0c363a1ed853 > > 100644 > > --- a/drivers/dma/xilinx/xilinx_dma.c > > +++ b/drivers/dma/xilinx/xilinx_dma.c > > @@ -3245,7 +3245,7 @@ static int xilinx_dma_probe(struct platform_device > > *pdev) > > * > > * Return: Always '0' > > */ > > Nit - kernel-doc return documentation needs to be updated. Good catch, I should add that to my pre-send checks. I fixed it in my tree, so an eventual v2 will be good. I'll wait a bit before resending. @Vinod: If you pick up this series, feel free to skip this patch or fixup with diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index 0c363a1ed853..e40696f6f864 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -3242,8 +3242,6 @@ static int xilinx_dma_probe(struct platform_device *pdev) /** * xilinx_dma_remove - Driver remove function * @pdev: Pointer to the platform_device structure - * - * Return: Always '0' */ static void xilinx_dma_remove(struct platform_device *pdev) { or apply as is (in which case I will follow up with a separate patch to fix this). Thanks Uwe
On 28-09-23, 09:27, Uwe Kleine-König wrote: > > Good catch, I should add that to my pre-send checks. I fixed it in my > tree, so an eventual v2 will be good. I'll wait a bit before resending. > > @Vinod: If you pick up this series, feel free to skip this patch or > fixup with > > diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c > index 0c363a1ed853..e40696f6f864 100644 > --- a/drivers/dma/xilinx/xilinx_dma.c > +++ b/drivers/dma/xilinx/xilinx_dma.c > @@ -3242,8 +3242,6 @@ static int xilinx_dma_probe(struct platform_device *pdev) > /** > * xilinx_dma_remove - Driver remove function > * @pdev: Pointer to the platform_device structure > - * > - * Return: Always '0' > */ > static void xilinx_dma_remove(struct platform_device *pdev) > { > > or apply as is (in which case I will follow up with a separate patch to > fix this). Follow up patch is easier to handle Thanks
diff --git a/drivers/dma/xilinx/xilinx_dma.c b/drivers/dma/xilinx/xilinx_dma.c index 0a3b2e22f23d..0c363a1ed853 100644 --- a/drivers/dma/xilinx/xilinx_dma.c +++ b/drivers/dma/xilinx/xilinx_dma.c @@ -3245,7 +3245,7 @@ static int xilinx_dma_probe(struct platform_device *pdev) * * Return: Always '0' */ -static int xilinx_dma_remove(struct platform_device *pdev) +static void xilinx_dma_remove(struct platform_device *pdev) { struct xilinx_dma_device *xdev = platform_get_drvdata(pdev); int i; @@ -3259,8 +3259,6 @@ static int xilinx_dma_remove(struct platform_device *pdev) xilinx_dma_chan_remove(xdev->chan[i]); xdma_disable_allclks(xdev); - - return 0; } static struct platform_driver xilinx_vdma_driver = { @@ -3269,7 +3267,7 @@ static struct platform_driver xilinx_vdma_driver = { .of_match_table = xilinx_dma_of_ids, }, .probe = xilinx_dma_probe, - .remove = xilinx_dma_remove, + .remove_new = xilinx_dma_remove, }; module_platform_driver(xilinx_vdma_driver);
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 ignored (apart from emitting a warning) 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. Eventually after all drivers are converted, .remove_new() is renamed to .remove(). 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/dma/xilinx/xilinx_dma.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)