From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [PATCH 1/4] dmaengine: qcom: bam_dma: make bam clk optional Date: Tue, 23 Jan 2018 14:49:05 +0530 Message-ID: <20180123091905.GY18649@localhost> References: <20180116190236.14558-1-srinivas.kandagatla@linaro.org> <20180116190236.14558-2-srinivas.kandagatla@linaro.org> <20180119055221.GV18649@localhost> <8dfa8ba1-6e98-a8e4-614c-592861cef571@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <8dfa8ba1-6e98-a8e4-614c-592861cef571-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Srinivas Kandagatla Cc: Andy Gross , dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Rob Herring , Mark Rutland , David Brown , Dan Williams , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-soc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, yanhe-jfJNa2p1gH1BDgjK7y7TUQ@public.gmane.org, ramkri-Rm6X0d1/PG5y9aJCnZT0Uw@public.gmane.org, sdharia-jfJNa2p1gH1BDgjK7y7TUQ@public.gmane.org List-Id: devicetree@vger.kernel.org On Mon, Jan 22, 2018 at 09:55:01AM +0000, Srinivas Kandagatla wrote: > >>@@ -1180,13 +1180,14 @@ static int bam_dma_probe(struct platform_device *pdev) > >> "qcom,controlled-remotely"); > >> bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk"); > > > >but you still do clk_get unconditionally? > > Only reason to do this way is to not break existing users in the mainline. > > remotely controlled BAM is already supported in upstream driver, there are > users of this who pass clk from device tree, If I make this conditional then > subsequent reads to the BAM registers for those instances might crash the > system. But these instances are remote controlled, so if we stop representing them in Linux, why would we read them? -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html