| Message ID | HK0PR01MB280106E1D78EF51A5B8ED8BFF8CE9@HK0PR01MB2801.apcprd01.prod.exchangelabs.com |
|---|---|
| State | New |
| Headers | show |
| Series | USB / dwc3: remove the use of -ENOSYS from core.c | expand |
On Thu, 2022-05-19 at 17:59 +0200, Greg KH wrote: > On Tue, May 17, 2022 at 08:22:00PM +0530, Kushagra Verma wrote: > > This patch removes the use of -ENOSYS as it is used when users try > > to call a > > syscall that doesn't exist. So, we don't need to check if 'ret == - > > ENOSYS'. > > ENOSYS is also used internally in the kernel for other things. > > > > > Signed-off-by: Kushagra Verma <kushagra765@outlook.com> > > --- > > drivers/usb/dwc3/core.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > index c78205c5e19f..3c1a877d5183 100644 > > --- a/drivers/usb/dwc3/core.c > > +++ b/drivers/usb/dwc3/core.c > > @@ -1283,7 +1283,7 @@ static int dwc3_core_get_phy(struct dwc3 > > *dwc) > > dwc->usb2_generic_phy = devm_phy_get(dev, "usb2-phy"); > > if (IS_ERR(dwc->usb2_generic_phy)) { > > ret = PTR_ERR(dwc->usb2_generic_phy); > > - if (ret == -ENOSYS || ret == -ENODEV) > > + if (ret == -ENODEV) > > Did you validate that no callers can ever set this to ENOSYS? Yes, I think no callers should ever set ret to ENOSYS unless it comes under the other things ENOSYS is used for. > > Why was this added in the first place? What commit added it? This was added by commit 57303488cd37d ("usb: dwc3: adapt dwc3 core to use Generic PHY Framework"). > > thanks, > > greg k-h Thanks, Kushagra
On Fri, 2022-05-20 at 10:24 +0200, Greg KH wrote: > On Fri, May 20, 2022 at 12:16:29PM +0530, Kushagra Verma wrote: > > On Thu, 2022-05-19 at 17:59 +0200, Greg KH wrote: > > > On Tue, May 17, 2022 at 08:22:00PM +0530, Kushagra Verma wrote: > > > > This patch removes the use of -ENOSYS as it is used when users try > > > > to call a > > > > syscall that doesn't exist. So, we don't need to check if 'ret == - > > > > ENOSYS'. > > > > > > ENOSYS is also used internally in the kernel for other things. > > > > > > > > > > > Signed-off-by: Kushagra Verma <kushagra765@outlook.com> > > > > --- > > > > drivers/usb/dwc3/core.c | 4 ++-- > > > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > > > > index c78205c5e19f..3c1a877d5183 100644 > > > > --- a/drivers/usb/dwc3/core.c > > > > +++ b/drivers/usb/dwc3/core.c > > > > @@ -1283,7 +1283,7 @@ static int dwc3_core_get_phy(struct dwc3 > > > > *dwc) > > > > dwc->usb2_generic_phy = devm_phy_get(dev, "usb2-phy"); > > > > if (IS_ERR(dwc->usb2_generic_phy)) { > > > > ret = PTR_ERR(dwc->usb2_generic_phy); > > > > - if (ret == -ENOSYS || ret == -ENODEV) > > > > + if (ret == -ENODEV) > > > > > > Did you validate that no callers can ever set this to ENOSYS? > > Yes, I think no callers should ever set ret to ENOSYS unless it comes under the other things ENOSYS is used for. > > Please audit the code to verify this and document it in the changelog > text when you resend this. I have audited the code and none of the callers return -ENOSYS. The devm_phy_get function calls phy_get to lookup and obtain a reference to a phy. This function returns the phy driver or -ENODEV if there is no such phy (according to the comments above it). > > > > Why was this added in the first place? What commit added it? > > This was added by commit 57303488cd37d ("usb: dwc3: adapt dwc3 core to use Generic PHY Framework"). > > Great, please also include that information. Ok. > > thanks, > > greg k-h Thanks, Kushagra
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index c78205c5e19f..3c1a877d5183 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -1283,7 +1283,7 @@ static int dwc3_core_get_phy(struct dwc3 *dwc) dwc->usb2_generic_phy = devm_phy_get(dev, "usb2-phy"); if (IS_ERR(dwc->usb2_generic_phy)) { ret = PTR_ERR(dwc->usb2_generic_phy); - if (ret == -ENOSYS || ret == -ENODEV) + if (ret == -ENODEV) dwc->usb2_generic_phy = NULL; else return dev_err_probe(dev, ret, "no usb2 phy configured\n"); @@ -1292,7 +1292,7 @@ static int dwc3_core_get_phy(struct dwc3 *dwc) dwc->usb3_generic_phy = devm_phy_get(dev, "usb3-phy"); if (IS_ERR(dwc->usb3_generic_phy)) { ret = PTR_ERR(dwc->usb3_generic_phy); - if (ret == -ENOSYS || ret == -ENODEV) + if (ret == -ENODEV) dwc->usb3_generic_phy = NULL; else return dev_err_probe(dev, ret, "no usb3 phy configured\n");
This patch removes the use of -ENOSYS as it is used when users try to call a syscall that doesn't exist. So, we don't need to check if 'ret == -ENOSYS'. Signed-off-by: Kushagra Verma <kushagra765@outlook.com> --- drivers/usb/dwc3/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)