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[PATCH] rust: opp: use to_result for error handling

Onur Özkan posted 1 patch 1 month, 1 week ago 
rust/kernel/opp.rs | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)
[PATCH] rust: opp: use to_result for error handling
Posted by Onur Özkan 1 month, 1 week ago 
Simplifies error handling by replacing the manual check
of the return value with the `to_result` helper.

Signed-off-by: Onur Özkan <work@onurozkan.dev>
---
 rust/kernel/opp.rs | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/rust/kernel/opp.rs b/rust/kernel/opp.rs
index 08126035d2c6..9d79c2816af5 100644
--- a/rust/kernel/opp.rs
+++ b/rust/kernel/opp.rs
@@ -12,7 +12,7 @@
     clk::Hertz,
     cpumask::{Cpumask, CpumaskVar},
     device::Device,
-    error::{code::*, from_err_ptr, from_result, to_result, Error, Result, VTABLE_DEFAULT_ERROR},
+    error::{code::*, from_err_ptr, from_result, to_result, Result, VTABLE_DEFAULT_ERROR},
     ffi::c_ulong,
     prelude::*,
     str::CString,
@@ -500,11 +500,8 @@ pub fn set(self, dev: &Device) -> Result<ConfigToken> {
         // requirements. The OPP core guarantees not to access fields of [`Config`] after this call
         // and so we don't need to save a copy of them for future use.
         let ret = unsafe { bindings::dev_pm_opp_set_config(dev.as_raw(), &mut config) };
-        if ret < 0 {
-            Err(Error::from_errno(ret))
-        } else {
-            Ok(ConfigToken(ret))
-        }
+
+        to_result(ret).map(|()| ConfigToken(ret))
     }

     /// Config's clk callback.
@@ -713,11 +710,8 @@ pub fn opp_count(&self) -> Result<u32> {
         // SAFETY: The requirements are satisfied by the existence of [`Device`] and its safety
         // requirements.
         let ret = unsafe { bindings::dev_pm_opp_get_opp_count(self.dev.as_raw()) };
-        if ret < 0 {
-            Err(Error::from_errno(ret))
-        } else {
-            Ok(ret as u32)
-        }
+
+        to_result(ret).map(|()| ret as u32)
     }

     /// Returns max clock latency (in nanoseconds) of the [`OPP`]s in the [`Table`].
--
2.50.0
Re: [PATCH] rust: opp: use to_result for error handling
Posted by Elle Rhumsaa 1 month, 1 week ago 
On Thu, Aug 21, 2025 at 12:16:05PM +0300, Onur Özkan wrote:
> Simplifies error handling by replacing the manual check
> of the return value with the `to_result` helper.
> 
> Signed-off-by: Onur Özkan <work@onurozkan.dev>
> ---
>  rust/kernel/opp.rs | 16 +++++-----------
>  1 file changed, 5 insertions(+), 11 deletions(-)
> 
> diff --git a/rust/kernel/opp.rs b/rust/kernel/opp.rs
> index 08126035d2c6..9d79c2816af5 100644
> --- a/rust/kernel/opp.rs
> +++ b/rust/kernel/opp.rs
> @@ -12,7 +12,7 @@
>      clk::Hertz,
>      cpumask::{Cpumask, CpumaskVar},
>      device::Device,
> -    error::{code::*, from_err_ptr, from_result, to_result, Error, Result, VTABLE_DEFAULT_ERROR},
> +    error::{code::*, from_err_ptr, from_result, to_result, Result, VTABLE_DEFAULT_ERROR},
>      ffi::c_ulong,
>      prelude::*,
>      str::CString,
> @@ -500,11 +500,8 @@ pub fn set(self, dev: &Device) -> Result<ConfigToken> {
>          // requirements. The OPP core guarantees not to access fields of [`Config`] after this call
>          // and so we don't need to save a copy of them for future use.
>          let ret = unsafe { bindings::dev_pm_opp_set_config(dev.as_raw(), &mut config) };
> -        if ret < 0 {
> -            Err(Error::from_errno(ret))
> -        } else {
> -            Ok(ConfigToken(ret))
> -        }
> +
> +        to_result(ret).map(|()| ConfigToken(ret))
>      }
> 
>      /// Config's clk callback.
> @@ -713,11 +710,8 @@ pub fn opp_count(&self) -> Result<u32> {
>          // SAFETY: The requirements are satisfied by the existence of [`Device`] and its safety
>          // requirements.
>          let ret = unsafe { bindings::dev_pm_opp_get_opp_count(self.dev.as_raw()) };
> -        if ret < 0 {
> -            Err(Error::from_errno(ret))
> -        } else {
> -            Ok(ret as u32)
> -        }
> +
> +        to_result(ret).map(|()| ret as u32)
>      }
> 
>      /// Returns max clock latency (in nanoseconds) of the [`OPP`]s in the [`Table`].
> --
> 2.50.0

Reviewed-by: Elle Rhumsaa <elle@weathered-steel.dev>
Re: [PATCH] rust: opp: use to_result for error handling
Posted by Viresh Kumar 1 month, 1 week ago 
On 21-08-25, 12:16, Onur Özkan wrote:
> Simplifies error handling by replacing the manual check
> of the return value with the `to_result` helper.
> 
> Signed-off-by: Onur Özkan <work@onurozkan.dev>
> ---
>  rust/kernel/opp.rs | 16 +++++-----------
>  1 file changed, 5 insertions(+), 11 deletions(-)

Applied. Thanks.

-- 
viresh
Re: [PATCH] rust: opp: use to_result for error handling
Posted by Viresh Kumar 1 month, 1 week ago 
On 21-08-25, 12:16, Onur Özkan wrote:
> Simplifies error handling by replacing the manual check
> of the return value with the `to_result` helper.
> 
> Signed-off-by: Onur Özkan <work@onurozkan.dev>
> ---
>  rust/kernel/opp.rs | 16 +++++-----------
>  1 file changed, 5 insertions(+), 11 deletions(-)
> 
> diff --git a/rust/kernel/opp.rs b/rust/kernel/opp.rs
> index 08126035d2c6..9d79c2816af5 100644
> --- a/rust/kernel/opp.rs
> +++ b/rust/kernel/opp.rs
> @@ -12,7 +12,7 @@
>      clk::Hertz,
>      cpumask::{Cpumask, CpumaskVar},
>      device::Device,
> -    error::{code::*, from_err_ptr, from_result, to_result, Error, Result, VTABLE_DEFAULT_ERROR},
> +    error::{code::*, from_err_ptr, from_result, to_result, Result, VTABLE_DEFAULT_ERROR},
>      ffi::c_ulong,
>      prelude::*,
>      str::CString,
> @@ -500,11 +500,8 @@ pub fn set(self, dev: &Device) -> Result<ConfigToken> {
>          // requirements. The OPP core guarantees not to access fields of [`Config`] after this call
>          // and so we don't need to save a copy of them for future use.
>          let ret = unsafe { bindings::dev_pm_opp_set_config(dev.as_raw(), &mut config) };
> -        if ret < 0 {
> -            Err(Error::from_errno(ret))
> -        } else {
> -            Ok(ConfigToken(ret))
> -        }
> +
> +        to_result(ret).map(|()| ConfigToken(ret))
>      }
> 
>      /// Config's clk callback.
> @@ -713,11 +710,8 @@ pub fn opp_count(&self) -> Result<u32> {
>          // SAFETY: The requirements are satisfied by the existence of [`Device`] and its safety
>          // requirements.
>          let ret = unsafe { bindings::dev_pm_opp_get_opp_count(self.dev.as_raw()) };
> -        if ret < 0 {
> -            Err(Error::from_errno(ret))
> -        } else {
> -            Ok(ret as u32)
> -        }
> +
> +        to_result(ret).map(|()| ret as u32)
>      }

I would get rid of `ret` as well in both the cases, like it is done by
other users of `to_result()`.

-- 
viresh
Re: [PATCH] rust: opp: use to_result for error handling
Posted by Onur Özkan 1 month, 1 week ago 
On Thu, 21 Aug 2025 14:51:37 +0530
Viresh Kumar <viresh.kumar@linaro.org> wrote:

> On 21-08-25, 12:16, Onur Özkan wrote:
> > Simplifies error handling by replacing the manual check
> > of the return value with the `to_result` helper.
> > 
> > Signed-off-by: Onur Özkan <work@onurozkan.dev>
> > ---
> >  rust/kernel/opp.rs | 16 +++++-----------
> >  1 file changed, 5 insertions(+), 11 deletions(-)
> > 
> > diff --git a/rust/kernel/opp.rs b/rust/kernel/opp.rs
> > index 08126035d2c6..9d79c2816af5 100644
> > --- a/rust/kernel/opp.rs
> > +++ b/rust/kernel/opp.rs
> > @@ -12,7 +12,7 @@
> >      clk::Hertz,
> >      cpumask::{Cpumask, CpumaskVar},
> >      device::Device,
> > -    error::{code::*, from_err_ptr, from_result, to_result, Error,
> > Result, VTABLE_DEFAULT_ERROR},
> > +    error::{code::*, from_err_ptr, from_result, to_result, Result,
> > VTABLE_DEFAULT_ERROR}, ffi::c_ulong,
> >      prelude::*,
> >      str::CString,
> > @@ -500,11 +500,8 @@ pub fn set(self, dev: &Device) ->
> > Result<ConfigToken> { // requirements. The OPP core guarantees not
> > to access fields of [`Config`] after this call // and so we don't
> > need to save a copy of them for future use. let ret = unsafe {
> > bindings::dev_pm_opp_set_config(dev.as_raw(), &mut config) };
> > -        if ret < 0 {
> > -            Err(Error::from_errno(ret))
> > -        } else {
> > -            Ok(ConfigToken(ret))
> > -        }
> > +
> > +        to_result(ret).map(|()| ConfigToken(ret))
> >      }
> > 
> >      /// Config's clk callback.
> > @@ -713,11 +710,8 @@ pub fn opp_count(&self) -> Result<u32> {
> >          // SAFETY: The requirements are satisfied by the existence
> > of [`Device`] and its safety // requirements.
> >          let ret = unsafe {
> > bindings::dev_pm_opp_get_opp_count(self.dev.as_raw()) };
> > -        if ret < 0 {
> > -            Err(Error::from_errno(ret))
> > -        } else {
> > -            Ok(ret as u32)
> > -        }
> > +
> > +        to_result(ret).map(|()| ret as u32)
> >      }
> 
> I would get rid of `ret` as well in both the cases, like it is done by
> other users of `to_result()`.
> 

`ret` is returned at the end unlike other `to_result` usages in other
functions.

-Onur
Re: [PATCH] rust: opp: use to_result for error handling
Posted by Viresh Kumar 1 month, 1 week ago 
On 22-08-25, 08:13, Onur Özkan wrote:
> `ret` is returned at the end unlike other `to_result` usages in other
> functions.

Ahh, I missed that to_result() doesn't return `ret` at all.

-- 
viresh

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