linux-kernel - Re: [PATCH] regmap: Allow read_reg

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <542B1ABE.5000900@metafoo.de>
Date:	Tue, 30 Sep 2014 23:03:58 +0200
From:	Lars-Peter Clausen <lars@...afoo.de>
To:	Dan Murphy <dmurphy@...com>, broonie@...nel.org,
	gregkh@...uxfoundation.org
CC:	linux-kernel@...r.kernel.org, linux-omap@...r.kernel.org
Subject: Re: [PATCH] regmap: Allow read_reg_mask to be 0

On 09/30/2014 06:07 PM, Dan Murphy wrote:
> There may be spi devices that do not require a
> register read mask to read the registers.
>
> Currently the code sets the read mask based on
> a non-zero value passed in from the driver or if that
> value is 0 sets the read mask to 0x80.

It only sets it to the bus default if both read_flag_mask and 
write_flag_mask are 0. The assumption is that both of them being zero is a 
invalid configuration and either of them (or both) have to be non-zero for 
proper operation, since otherwise the device can't tell the difference 
between a read and a write.

Do you have a device where both the read and the write mask is 0?

- Lars
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/