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Thu, 22 Jul 2021 09:31:38 +0000 Message-ID: <9117e5212a3b743ca541918ec2b701c159ac752c.camel@nxp.com> Subject: Re: [PATCH v2 2/3] clk: fractional-divider: Introduce NO_PRESCALER flag From: Liu Ying To: 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 Cc: Michael Turquette , NXP Linux Team , Jacky Bai Date: Thu, 22 Jul 2021 17:29:23 +0800 In-Reply-To: <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> References: <20210716133448.24890-1-andriy.shevchenko@linux.intel.com> <20210716133448.24890-2-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.36.4-0ubuntu1 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SGXP274CA0007.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b8::19) 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 SGXP274CA0007.SGPP274.PROD.OUTLOOK.COM (2603:1096:4:b8::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4352.25 via Frontend Transport; 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As I mentioned in v1 comment, it seems to be good to decouple the prescaler knowledge from this common fractional divider clk driver. This way, we'll make it simpler and easier to maintain. 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. 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. Regards, Liu Ying > > Reported-by: Liu Ying > Signed-off-by: Andy Shevchenko > --- > v2: moved entire snipped under new flag check (Liu) > drivers/clk/clk-fractional-divider.c | 10 ++++++---- > include/linux/clk-provider.h | 5 +++++ > 2 files changed, 11 insertions(+), 4 deletions(-)