From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Date: Thu, 17 Sep 2015 07:30:06 +0000 Subject: Re: [PATCH 00/14] SCI clocks cleanup Message-Id: <20150917073006.GA5414@verge.net.au> List-Id: References: <1442232876-27629-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> In-Reply-To: <1442232876-27629-1-git-send-email-laurent.pinchart+renesas@ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On Mon, Sep 14, 2015 at 03:14:22PM +0300, Laurent Pinchart wrote: > Hello, > > The SCI driver currently handles two clocks, an interface clock named sci_ick > and a functional clock named sci_fck. Studying the datasheets of the SH and > ARM SoCs that incorportate (H)SCI(F)([AB]) instances showed (un)surprisingly > that the hardware doesn't have a separate controllable interface clock. > > All the platforms that declare an interface clock for the SCI set it to the > clock used as the SCI functional clock. The two clocks can thus be merged on > the driver side, which is what this patch series does. The resulting clock is > called "fck", and all SH and ARM users (both DT and non-DT) are fixed to name > their SCI clocks appropriately. > > Support for the "sci_ick" name is kept in the sh-sci driver to ensure DT > backward compatibility, and support for the "peripheral_clk" clock to not > break SH platforms that don't declare device-specific SCI clocks. The later > can be removed when all SH platforms will declare their SCI clocks properly. > > The patches have been developed for an ancien (v3.x for those who were born) > kernel and rebased on top of Simon's master branch. I've only compile-tested > them after the rebase. Geert, I believe this series is a good preliminary > cleanup for the SCI baud rate generator clock support. Could you give it a try > as part of your work on that ? FWIW, given the explanation above, particularly that regarding backwards compatibility for DT, I am comfortable with these changes.