From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lars-Peter Clausen Subject: Re: [PATCH] regmap: Allow read_reg_mask to be 0 Date: Tue, 30 Sep 2014 23:03:58 +0200 Message-ID: <542B1ABE.5000900@metafoo.de> References: <1412093220-24690-1-git-send-email-dmurphy@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1412093220-24690-1-git-send-email-dmurphy@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Dan Murphy , broonie@kernel.org, gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org List-Id: linux-omap@vger.kernel.org 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