From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <5596B462.6050103@arm.com> Date: Fri, 03 Jul 2015 17:12:18 +0100 From: Sudeep Holla MIME-Version: 1.0 To: Stephen Boyd CC: Sudeep Holla , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linux-clk@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Liviu Dudau , Lorenzo Pieralisi , "Jon Medhurst (Tixy)" , Arnd Bergmann , Kevin Hilman , Olof Johansson , Mike Turquette Subject: Re: [PATCH v4 3/8] clk: add support for clocks provided by SCP(System Control Processor) References: <1433760002-24120-1-git-send-email-sudeep.holla@arm.com> <1433760002-24120-4-git-send-email-sudeep.holla@arm.com> <20150702172310.GF4301@codeaurora.org> <5596A1B6.8020307@arm.com> In-Reply-To: <5596A1B6.8020307@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed List-ID: On 03/07/15 15:52, Sudeep Holla wrote: [...] >>> +static int scpi_clk_set_rate(struct clk_hw *hw, unsigned long rate, >>> + unsigned long parent_rate) >>> +{ >>> + struct scpi_clk *clk = to_scpi_clk(hw); >>> + >>> + return clk->scpi_ops->clk_set_val(clk->id, rate); >>> +} >>> + >>> +static void scpi_clk_disable(struct clk_hw *hw) >>> +{ >>> + scpi_clk_set_rate(hw, 0, 0); >> >> Does this mean you have to set a rate to enable the clock? Are >> you relying on drivers to call clk_set_rate() to implicitly >> enable the clock? If so, it would be better to cache the rate of >> the clock in set_rate if the clock isn't enabled in software and >> then send the cached rate during enable. >> > > Agreed, I have asked the firmware/SCPI specification guys about > more details on what to expect from firmware. Once they get back, > will update the code considering your feedback. > OK, I got feedback and looks like it was never planned to implement that and even specification needs to be fixed. So I will drop the disable callback support. For now, we don't support {en,dis}able features. We need to amend the specification to fix that. Regards, Sudeep