| Message ID | 1466080749-23567-1-git-send-email-jonathanh@nvidia.com |
|---|---|
| State | New |
| Headers | show |
On 16/06/16 13:39, Jon Hunter wrote: > When pinctrl_get() is called for a device, it will return a valid handle > even if the device itself has no pinctrl state entries defined in > device-tree. This is caused by the function pinctrl_dt_to_map() which > will return success even if the first pinctrl state, 'pinctrl-0', is not > found in the device-tree node for a device. > > According to the pinctrl device-tree binding documentation, pinctrl > states must be numbered starting from 0 and so 'pinctrl-0' should always > be present if a device uses pinctrl and therefore, if 'pinctrl-0' is not > present it seems valid that we should not return a valid pinctrl handle. > > Fix this by returning an error code if the property 'pinctrl-0' is not > present for a device. > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com> > --- > > I was wondering if this meant we are creating pinctrl handles for > devices on boot that don't use pinctrl (when > calling pinctrl_bind_pins()). However, although devm_pinctrl_get() > does return successful for all devices, the subsequent call to > pinctrl_lookup_state() (to get the default state) will fail and so > we will destroy the pinctrl handle afterall. > > drivers/pinctrl/devicetree.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c > index fe04e748dfe4..f41c16e11a11 100644 > --- a/drivers/pinctrl/devicetree.c > +++ b/drivers/pinctrl/devicetree.c > @@ -195,8 +195,11 @@ int pinctrl_dt_to_map(struct pinctrl *p) > propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state); > prop = of_find_property(np, propname, &size); > kfree(propname); > - if (!prop) > + if (!prop) { > + if (state == 0) I think there should be a of_node_put() here. Will resend. > + return -ENODEV; > break; > + } Cheers Jon
diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c index fe04e748dfe4..f41c16e11a11 100644 --- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -195,8 +195,11 @@ int pinctrl_dt_to_map(struct pinctrl *p) propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state); prop = of_find_property(np, propname, &size); kfree(propname); - if (!prop) + if (!prop) { + if (state == 0) + return -ENODEV; break; + } list = prop->value; size /= sizeof(*list);
When pinctrl_get() is called for a device, it will return a valid handle even if the device itself has no pinctrl state entries defined in device-tree. This is caused by the function pinctrl_dt_to_map() which will return success even if the first pinctrl state, 'pinctrl-0', is not found in the device-tree node for a device. According to the pinctrl device-tree binding documentation, pinctrl states must be numbered starting from 0 and so 'pinctrl-0' should always be present if a device uses pinctrl and therefore, if 'pinctrl-0' is not present it seems valid that we should not return a valid pinctrl handle. Fix this by returning an error code if the property 'pinctrl-0' is not present for a device. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> --- I was wondering if this meant we are creating pinctrl handles for devices on boot that don't use pinctrl (when calling pinctrl_bind_pins()). However, although devm_pinctrl_get() does return successful for all devices, the subsequent call to pinctrl_lookup_state() (to get the default state) will fail and so we will destroy the pinctrl handle afterall. drivers/pinctrl/devicetree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)