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Thu, 22 Jul 2021 09:46:03 +0000 Message-ID: <08ca856c013aba60e686f050e06a6e3179de6030.camel@nxp.com> Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag From: Liu Ying To: Andy Shevchenko Cc: Andy Shevchenko , Heiko Stuebner , Elaine Zhang , Stephen Boyd , linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, Michael Turquette , NXP Linux Team , Jacky Bai Date: Thu, 22 Jul 2021 17:43:49 +0800 In-Reply-To: References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.4-0ubuntu1 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) To AM7PR04MB7046.eurprd04.prod.outlook.com (2603:10a6:20b:113::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from blueberry (119.31.174.66) by SGBP274CA0002.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.24 via Frontend Transport; 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Also, then, the > > NO_PRESCALER flag is not needed at all. However, it seems that two > > Intel drivers which use the frational divider drivers will be affected > > and rate negotiation logics need to be implemented for them. Please > > consider if it's doable or not. > > The current driver works for the certain hardware without this change. > If you think it's better, submit a proposal we will discuss. Well, I'm not afford to do so. Just share an idea. I haven't got the intel HW to test. As I mentioned in v1 comment, it seems that you have experience on relevent drivers and HW to test, may I encourage you to do that :-) Or forget that if you really think you won't do that. > > > If we ultimately keep the prescaler knowledge here, please consider to > > add the NO_PRESCALER flag for i.MX7ulp as it hasn't the prescaler IIUC. > > You mean there is a code which is currently using this driver w/o > taking into account this prescaller flavour? Can you, please, point > out, I'll definitely update it. Thanks for the catch! drivers/clk/imx/clk-composite-7ulp.c Regards, Liu Ying >