From: Krzysztof Kozlowski <krzk@kernel.org>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>,
Rich Felker <dalias@libc.org>,
Linux-sh list <linux-sh@vger.kernel.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH] sh: clk: Fix discarding const qualifier warning
Date: Tue, 7 Jan 2020 14:05:14 +0100 [thread overview]
Message-ID: <CAJKOXPcbUfUcmU2O50M5Hs2y6ggg-m5qU-AJ6HjSL9dFTCp64A@mail.gmail.com> (raw)
In-Reply-To: <CAMuHMdULcBE1inRzTRFJeRDToT1wW+nrMEfiUs7DxMLR0tqb3w@mail.gmail.com>
On Tue, 7 Jan 2020 at 14:00, Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Krzysztof,
>
> On Tue, Jan 7, 2020 at 1:26 PM Krzysztof Kozlowski <krzk@kernel.org> wrote:
> > ioreadX() accepts pointer to non-const memory. This fixes warnings
> > like:
> >
> > drivers/sh/clk/cpg.c: In function ‘r8’:
> > drivers/sh/clk/cpg.c:41:17: warning: passing argument 1 of ‘ioread8’
> > discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
> >
> > Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
>
> Thanks for your patch!
>
> > --- a/drivers/sh/clk/cpg.c
> > +++ b/drivers/sh/clk/cpg.c
> > @@ -36,17 +36,17 @@ static void sh_clk_write(int value, struct clk *clk)
> > iowrite32(value, clk->mapped_reg);
> > }
> >
> > -static unsigned int r8(const void __iomem *addr)
> > +static unsigned int r8(void __iomem *addr)
> > {
> > return ioread8(addr);
> > }
>
> Isn't the real issue that some implementations of ioreadX() take const,
> while others don't?
>
> Even the generic ones disagree:
>
> include/asm-generic/io.h:static inline u8 ioread8(const volatile
> void __iomem *addr)
> include/asm-generic/iomap.h:extern unsigned int ioread8(void __iomem *);
>
> IMHO they all should take "const volatile void __iomem *".
Since this is a SuperH driver, I adjusted it to the SuperH
implementation - lack of const. However iIndeed it makes sense to have
them all taking "const"... Let me check, if I can fix it (without the
real HW).
Best regards,
Krzysztof
next prev parent reply other threads:[~2020-01-07 13:05 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-07 12:26 [PATCH] sh: clk: Fix discarding const qualifier warning Krzysztof Kozlowski
2020-01-07 13:00 ` Geert Uytterhoeven
2020-01-07 13:05 ` Krzysztof Kozlowski [this message]
2020-01-07 13:32 ` Krzysztof Kozlowski
2020-01-07 13:54 ` Arnd Bergmann
2020-01-07 14:04 ` Krzysztof Kozlowski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAJKOXPcbUfUcmU2O50M5Hs2y6ggg-m5qU-AJ6HjSL9dFTCp64A@mail.gmail.com \
--to=krzk@kernel.org \
--cc=arnd@arndb.de \
--cc=dalias@libc.org \
--cc=geert@linux-m68k.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=ysato@users.sourceforge.jp \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).