From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH v3 1/3] clk: Add safe switch hook Date: Wed, 9 Sep 2015 15:52:30 -0700 Message-ID: <20150909225230.GX15099@codeaurora.org> References: <1439387673-13015-1-git-send-email-georgi.djakov@linaro.org> <1439387673-13015-2-git-send-email-georgi.djakov@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:46566 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751055AbbIIWwc (ORCPT ); Wed, 9 Sep 2015 18:52:32 -0400 Content-Disposition: inline In-Reply-To: <1439387673-13015-2-git-send-email-georgi.djakov@linaro.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Georgi Djakov Cc: mturquette@baylibre.com, linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org On 08/12, Georgi Djakov wrote: > From: Stephen Boyd > > Sometimes clocks can't accept their parent source turning off > while the source is reprogrammed to a different rate. Most > notably CPU clocks require a way to switch away from the current > PLL they're running on, reprogram that PLL to a new rate, and > then switch back to the PLL with the new rate once they're done. > Add a hook that drivers can implement allowing them to return a > 'safe parent' and 'safe frequency' that they can switch their > parent to while the upstream source is reprogrammed to support > this. > > Signed-off-by: Stephen Boyd > Signed-off-by: Georgi Djakov Weird to be reviewing my own patch... Anyway, Mike tells me that coordinated clock rates are going to be on the list this month. We should use those patches instead of this safe parent/rate stuff. If the patches don't appear soon, we can look into having the clock provider handle the parent/rate switch itself. That isn't any worse that what we've been doing in other providers. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project