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Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH] iio: adc: ti-ads1015: support deferred probe Content-Language: en-US To: Lars-Peter Clausen , Jonathan Cameron , Andy Shevchenko Cc: linux-iio@vger.kernel.org, jic23@kernel.org, u.kleine-koenig@pengutronix.de References: <20230904101533.455896-1-tomas.melin@vaisala.com> <20230904141251.00002b7d@Huawei.com> <848d639c-43d1-bf92-2292-059dd1a019cf@vaisala.com> <38f995ab-99de-1d88-696e-edc78e24c8b2@metafoo.de> From: Tomas Melin In-Reply-To: <38f995ab-99de-1d88-696e-edc78e24c8b2@metafoo.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: GVYP280CA0009.SWEP280.PROD.OUTLOOK.COM (2603:10a6:150:fa::23) To HE1PR0602MB3625.eurprd06.prod.outlook.com (2603:10a6:7:81::18) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: HE1PR0602MB3625:EE_|VI1PR06MB6463:EE_ X-MS-Office365-Filtering-Correlation-Id: b6820e51-6b7f-4e12-f25e-08dbae9e64d2 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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Once a new resource becomes > available it will try again. In your case there is no resource > dependency, but just a random failure. So there is no guarantee that > probe will actually be called again since there might not be any new > resources that become available. > > The solution you've implemented might work on your specific platform, > but it does not work by design, it only works by chance. Returning > EPROBE_DEFER for things like IO errors is not the right approach. If you > need a quick hack you can for example write a small userspace script > that will trigger re-probe of the device at system startup. Right, I will need to take a different approach with this. Thanks for the input! Tomas > >