Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221130092847.2092-1-thunder.leizhen@huawei.com>
 <CAPDyKFphNdR-TorULpbsMtM6MzqsaK_UdSmG9Hin=wunUwJwJQ@mail.gmail.com> <d9d44a9c-e61e-2803-731b-cfa5f3d3d46c@huawei.com>
In-Reply-To: <d9d44a9c-e61e-2803-731b-cfa5f3d3d46c@huawei.com>
From:   Ulf Hansson <ulf.hansson@linaro.org>
Date:   Wed, 30 Nov 2022 12:33:24 +0100
Message-ID: <CAPDyKFrbRcEgtwbgBY8bsDW3YTtXJBS0zRhJq-Emf89hDWaUjg@mail.gmail.com>
Subject: Re: [PATCH] mmc: core: Fix error return code in sd_read_ext_regs()
To:     "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, 30 Nov 2022 at 12:18, Leizhen (ThunderTown)
<thunder.leizhen@huawei.com> wrote:
>
>
>
> On 2022/11/30 18:04, Ulf Hansson wrote:
> > On Wed, 30 Nov 2022 at 10:29, Zhen Lei <thunder.leizhen@huawei.com> wrote:
> >>
> >> Fix to return a negative error code from the error handling
> >> case instead of 0, as done elsewhere in this function.
> >>
> >> Fixes: c784f92769ae ("mmc: core: Read the SD function extension registers for power management")
> >> Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
> >> ---
> >>  drivers/mmc/core/sd.c | 1 +
> >>  1 file changed, 1 insertion(+)
> >>
> >> diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
> >> index 3662bf5320ce56d..7b64f76f0179ca8 100644
> >> --- a/drivers/mmc/core/sd.c
> >> +++ b/drivers/mmc/core/sd.c
> >> @@ -1277,6 +1277,7 @@ static int sd_read_ext_regs(struct mmc_card *card)
> >>         if (rev != 0 || len > 512) {
> >>                 pr_warn("%s: non-supported SD ext reg layout\n",
> >>                         mmc_hostname(card->host));
> >> +               err = -EOPNOTSUPP;
> >
> > The original intent was to not return an error code. Simply, because
> > the card remains functional and all but the new features from the SD
> > function extensions registers can still be used.
>
> OK, I got it.
>
> >
> > Perhaps, we should update the comment a few lines above to better
> > reflect that this is in-fact what we intend here.
>
> How about also add 'warning' to the output? The other two outputs
> contain the 'error' keyword.

There is already a pr_warn(), or is there something you want to add to that?

>
> >
> >>                 goto out;
> >>         }
> >>

Kind regards
Uffe