From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pratyush Yadav Date: Tue, 02 Jul 2024 14:15:31 -0000 Subject: [PATCH 4/9] mtd: devices: add AT24 eeprom support In-Reply-To: <20240702-congenial-vigilant-boar-aeae44@houat> (Maxime Ripard's message of "Tue, 2 Jul 2024 15:56:52 +0200") References: <20240701-b4-v6-10-topic-usbc-tcpci-v1-0-3fd5f4a193cc@pengutronix.de> <20240701-b4-v6-10-topic-usbc-tcpci-v1-4-3fd5f4a193cc@pengutronix.de> <07b701a9-7b52-45b7-8dba-1c25d77cbf15@linaro.org> <20240702-congenial-vigilant-boar-aeae44@houat> Message-ID: List-Id: To: linux-aspeed@lists.ozlabs.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Tue, Jul 02 2024, Maxime Ripard wrote: > On Tue, Jul 02, 2024 at 03:41:52PM GMT, Pratyush Yadav wrote: >> On Mon, Jul 01 2024, Tudor Ambarus wrote: >> >> > On 7/1/24 2:53 PM, Marco Felsch wrote: >> >> EEPROMs can become quite large nowadays (>=64K). Exposing such devices >> >> as single device isn't always sufficient. There may be partitions which >> >> require different access permissions. Also write access always need to >> >> to verify the offset. >> >> >> >> Port the current misc/eeprom/at24.c driver to the MTD framework since >> >> EEPROMs are memory-technology devices and the framework already supports >> > >> > I was under the impression that MTD devices are tightly coupled by erase >> > blocks. But then we see MTD_NO_ERASE, so what are MTD devices after all? >> >> I was curious as well so I did some digging. >> [...] >> >> I also found a thread from 2013 by Maxime Ripard (+Cc) suggesting adding >> EEPROMs to MTD [1]. The main purpose would have been unifying the EEPROM >> drivers under a single interface. I am not sure what came of it though, >> since I can't find any patches that followed up with the proposal. > > That discussion led to drivers/nvmem after I started to work on > some early prototype, and Srinivas took over that work. So would you say it is better for EEPROM drivers to use nvmem instead of moving under MTD? -- Regards, Pratyush Yadav