From: Sergei Shtylyov <sergei.shtylyov@gmail.com>
To: min.guo@mediatek.com, Bin Liu <b-liu@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Alan Stern <stern@rowland.harvard.edu>,
Matthias Brugger <matthias.bgg@gmail.com>,
chunfeng.yun@mediatek.com, linux-usb@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org
Subject: Re: [PATCH v3] usb: musb: remove unused variable 'devctl'
Date: Tue, 24 Nov 2020 12:13:42 +0300 [thread overview]
Message-ID: <c2f3f643-8514-5c4a-dd52-7abc8a6dc501@gmail.com> (raw)
In-Reply-To: <20201124084955.30270-1-min.guo@mediatek.com>
Hello!
On 24.11.2020 11:49, min.guo@mediatek.com wrote:
> From: Min Guo <min.guo@mediatek.com>
>
> Remove unused 'devctl' variable to fix compile warnings:
>
> drivers/usb/musb/musbhsdma.c: In function 'dma_controller_irq':
> drivers/usb/musb/musbhsdma.c:324:8: warning: variable 'devctl' set
> but not used [-Wunused-but-set-variable]
>
> Signed-off-by: Min Guo <min.guo@mediatek.com>
> ---
> changes in v3
> suggested by Greg Kroah-Hartman:
> Add a comment.
>
> changes in v2
> suggested by Alan Stern:
> Add void before musb_read to indicate that the register MUSB_DEVCTL
> was intended to be read and discarded.
> ---
> drivers/usb/musb/musbhsdma.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c
> index 0aacfc8be5a1..2a345b4ad015 100644
> --- a/drivers/usb/musb/musbhsdma.c
> +++ b/drivers/usb/musb/musbhsdma.c
[...]
> @@ -336,7 +334,11 @@ irqreturn_t dma_controller_irq(int irq, void *private_data)
> < musb_channel->len) ?
> "=> reconfig 0" : "=> complete");
>
> - devctl = musb_readb(mbase, MUSB_DEVCTL);
> + /*
> + * Some hardware may need to read the
> + * MUSB_DEVCTL register once to take effect.
> + */
> + (void)musb_readb(mbase, MUSB_DEVCTL);
Hm, forcibly reading DevCtl in the DMA driver... sounds quite
nonsensically. Lemme take a look...
[...]
MBR, Sergei
next prev parent reply other threads:[~2020-11-24 9:14 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-24 8:49 [PATCH v3] usb: musb: remove unused variable 'devctl' min.guo
2020-11-24 9:13 ` Sergei Shtylyov [this message]
2020-11-24 11:45 ` Sergei Shtylyov
2020-12-10 15:01 ` Greg Kroah-Hartman
2020-12-10 17:33 ` Sergei Shtylyov
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