From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Wed, 25 Jan 2017 09:26:02 +0100 Subject: [PATCH v3 1/13] mmc: sunxi: Fix clock frequency change sequence In-Reply-To: References: <6f6b511bce9df86ee43486653ac55df0d135f198.1484585798.git-series.maxime.ripard@free-electrons.com> Message-ID: <20170125082602.llunpuqwsimtzkds@lukather> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Ulf, On Tue, Jan 24, 2017 at 09:12:07AM +0100, Ulf Hansson wrote: > On 16 January 2017 at 17:56, Maxime Ripard > wrote: > > The MMC and SD specifications documents that the clock frequency should > > only be changed once gated. > > Where? > > > > > The current code first modifies the parent clock, gates it and then > > modifies the internal divider. This means that since the parent clock rate > > might be changed, the bus clock might be changed as well before it is > > gated, which breaks the specification. > > > > Move the gating before the parent rate modification. > > This all makes perfect sense to me, however I am not sure you need to > refer to the spec to justify these changes. I can't find it anymore :/ I'll resend that patch reworking the commit log. Thanks! Maxime -- Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 801 bytes Desc: not available URL: