| Message ID | 1374602524-3398-11-git-send-email-wsa@the-dreams.de |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, 2013-07-23 at 20:01 +0200, Wolfram Sang wrote: > devm_ioremap_resource does sanity checks on the given resource. No need to > duplicate this in the driver. Hi Wolfram: This is the first and only one of the patch series I looked at. > diff --git a/drivers/memory/tegra20-mc.c b/drivers/memory/tegra20-mc.c [] > @@ -218,8 +218,6 @@ static int tegra20_mc_probe(struct platform_device *pdev) > struct resource *res; > > res = platform_get_resource(pdev, IORESOURCE_MEM, i); > - if (!res) > - return -ENODEV; > mc->regs[i] = devm_ioremap_resource(&pdev->dev, res); I'm not so sure this is appropriate. devm_ioremap_resource returns ERR_PTR(-EINVAL) for null resource so this changes the return. devm_ioremap_resource also emits a noisy dev_err message when resource is NULL. It's a probe and before the message log would be silent but now there's a new dmesg. Perhaps that should be mentioned in the changelog here and elsewhere in the series. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/23/2013 11:25 AM, Joe Perches wrote: > On Tue, 2013-07-23 at 20:01 +0200, Wolfram Sang wrote: >> devm_ioremap_resource does sanity checks on the given resource. No need to >> duplicate this in the driver. > > Hi Wolfram: > > This is the first and only one of the patch series I looked at. > >> diff --git a/drivers/memory/tegra20-mc.c b/drivers/memory/tegra20-mc.c > [] >> @@ -218,8 +218,6 @@ static int tegra20_mc_probe(struct platform_device *pdev) >> struct resource *res; >> >> res = platform_get_resource(pdev, IORESOURCE_MEM, i); >> - if (!res) >> - return -ENODEV; >> mc->regs[i] = devm_ioremap_resource(&pdev->dev, res); > > I'm not so sure this is appropriate. > > devm_ioremap_resource returns ERR_PTR(-EINVAL) for > null resource so this changes the return. I think the exact return value is probably pretty arbitrary here. > devm_ioremap_resource also emits a noisy dev_err > message when resource is NULL. > > It's a probe and before the message log would be silent > but now there's a new dmesg. I think those changes are fine, at least for this driver. It's a bug if the required resources are missing, and having probe() actively point out why it's failing can only be a good thing in my book. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 07/23/2013 11:01 AM, Wolfram Sang wrote: > devm_ioremap_resource does sanity checks on the given resource. No need to > duplicate this in the driver. > > Signed-off-by: Wolfram Sang <wsa@the-dreams.de> > --- > Please apply via the subsystem-tree. Greg KH usually commits patches to thus tree. I Cc'd him here. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2013-07-23 at 18:27 -0700, Stephen Warren wrote: > On 07/23/2013 11:25 AM, Joe Perches wrote: > > On Tue, 2013-07-23 at 20:01 +0200, Wolfram Sang wrote: > >> devm_ioremap_resource does sanity checks on the given resource. No need to > >> duplicate this in the driver. [] > > This is the first and only one of the patch series I looked at. > > > >> diff --git a/drivers/memory/tegra20-mc.c b/drivers/memory/tegra20-mc.c > > [] > >> @@ -218,8 +218,6 @@ static int tegra20_mc_probe(struct platform_device *pdev) > >> struct resource *res; > >> > >> res = platform_get_resource(pdev, IORESOURCE_MEM, i); > >> - if (!res) > >> - return -ENODEV; > >> mc->regs[i] = devm_ioremap_resource(&pdev->dev, res); > > > > I'm not so sure this is appropriate. > > > > devm_ioremap_resource returns ERR_PTR(-EINVAL) for > > null resource so this changes the return. > > I think the exact return value is probably pretty arbitrary here. I think so as well, but it takes code inspection to determine whether or not there's any code impact. I want to make sure Wolfram has done that inspection. > > devm_ioremap_resource also emits a noisy dev_err > > message when resource is NULL. > > > > It's a probe and before the message log would be silent > > but now there's a new dmesg. > > I think those changes are fine, at least for this driver. It's a bug if > the required resources are missing, and having probe() actively point > out why it's failing can only be a good thing in my book. Again, I haven't looked at _all_ the paths for all of these patches, I just picked one at random. Extra dmesg output with some device probes that are expected to fail is not good. -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/memory/tegra20-mc.c b/drivers/memory/tegra20-mc.c index 0548eea..7cd82b8 100644 --- a/drivers/memory/tegra20-mc.c +++ b/drivers/memory/tegra20-mc.c @@ -218,8 +218,6 @@ static int tegra20_mc_probe(struct platform_device *pdev) struct resource *res; res = platform_get_resource(pdev, IORESOURCE_MEM, i); - if (!res) - return -ENODEV; mc->regs[i] = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(mc->regs[i])) return PTR_ERR(mc->regs[i]); diff --git a/drivers/memory/tegra30-mc.c b/drivers/memory/tegra30-mc.c index 58d2979..ef79345 100644 --- a/drivers/memory/tegra30-mc.c +++ b/drivers/memory/tegra30-mc.c @@ -340,8 +340,6 @@ static int tegra30_mc_probe(struct platform_device *pdev) struct resource *res; res = platform_get_resource(pdev, IORESOURCE_MEM, i); - if (!res) - return -ENODEV; mc->regs[i] = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(mc->regs[i])) return PTR_ERR(mc->regs[i]);
devm_ioremap_resource does sanity checks on the given resource. No need to duplicate this in the driver. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> --- Please apply via the subsystem-tree. drivers/memory/tegra20-mc.c | 2 -- drivers/memory/tegra30-mc.c | 2 -- 2 files changed, 4 deletions(-)