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SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200430_050753_518707_C9AF219C X-CRM114-Status: GOOD ( 18.46 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, Dongchun Zhu , linux-kernel@vger.kernel.org, Robert Foss , Tomasz Figa , Maxime Ripard , Andy Shevchenko , Fabio Estevam , linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 20-04-30 13:20, Sakari Ailus wrote: > On Thu, Apr 30, 2020 at 12:11:57PM +0200, Marco Felsch wrote: > > On 20-04-30 12:59, Sakari Ailus wrote: > > > Hi Marco, > > > > > > On Thu, Apr 30, 2020 at 11:53:32AM +0200, Marco Felsch wrote: > > > > Hi Sakari, > > > > > > > > On 20-04-30 12:45, Sakari Ailus wrote: > > > > > Hi Marco, > > > > > > > > > > On Thu, Apr 30, 2020 at 11:35:24AM +0200, Marco Felsch wrote: > > > > ... > > > > > > > > > - if (mclk != OV8856_MCLK) { > > > > > > > - dev_err(dev, "external clock %d is not supported", mclk); > > > > > > > - return -EINVAL; > > > > > > > + if (!is_acpi_node(fwnode)) { > > > > > > > + ov8856->xvclk = devm_clk_get(dev, "xvclk"); > > > > > > > + if (IS_ERR(ov8856->xvclk)) { > > > > > > > + dev_err(dev, "could not get xvclk clock (%pe)\n", > > > > > > > + ov8856->xvclk); > > > > > > > + return PTR_ERR(ov8856->xvclk); > > > > > > > + } > > > > > > > + > > > > > > > + clk_set_rate(ov8856->xvclk, xvclk_rate); > > > > > > > + xvclk_rate = clk_get_rate(ov8856->xvclk); > > > > > > > } > > > > > > > > > > > > Why do we handle the clock only in DT case? Is there a problem with the > > > > > > clock handling and ACPI? > > > > > > > > > > Not really, it's just that ACPI does not provide an interface to the clocks > > > > > as such. > > > > > > > > But you will get a clk by devm_clk_get()? > > > > > > No, because ACPI does not expose one to drivers. Effectively the entire > > > power sequences are implemented in ACPI, not in the driver. > > > > > > > Ah okay, thanks for the explanation. I'm really not into the ACPI > > stuff.. So this means the __power_off / power_on should only be done if > > we are using DT's? > > Correct. That's why it bails out early. It could be yet earlier though, > without doing anything. Yes I see. For easier and error less prone handling I would prefer: if (is_acpi_node()) return 0; as first instruction for __power_off/on(). Also I would refator the ov8856_check_hwcfg() so the common part can be used by this function and by a ov8856_parse_of() function. But thats only my opinion. Regards, Marco _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel