From: Alexander Dahl <ada@thorsis.com> To: linux-usb@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, rca@thorsis.com Subject: Enable HSIC Host Port on Atmel/Microchip SAMA5D2 Date: Mon, 23 Aug 2021 11:24:35 +0200 [thread overview] Message-ID: <2869763.XZdSvA6Ref@ada> (raw) Hello, for a new embedded board featuring a Microchip SAMA5D2 SoC (64 MiB SiP variant SAMA5D27C-D5M) we connected the third USB host port (HSIC only) with an USB3503 hub chip. This doesn't work out of the box with the Linux kernel currently, because neither the SoC nor the kernel does enable the HSIC interface by default. That SoC has three USB host ports, from the SAMA5D2 Series Datasheet [1] I learned there's a flag in an EHCI register, which has to be set to enable the HSIC interface on port C, the third port. (Section "41.7.14 EHCI: REG08 - HSIC Enable/Disable" of the datasheet.) I suppose that register is vendor specific. The register definitions in '/include/linux/usb/ehci_def.h' do not contain that register. Where would I add that register definition and set that flag in the kernel then? I suppose in the vendor specific ehci driver? That would be 'drivers/usb/host/ehci-atmel.c' right? Since that feature is optional (other boards don't need to turn on hsic on that port), some driver specific new device tree binding would be necessary, right? I suppose that would have to be documented in 'Documentation/ devicetree/bindings/usb/atmel-usb.txt' right? (Or that would have to be converted to yaml first?) Is this the right track? If yes, I'm going to develop patches for this. Otherwise any hint into the right direction are highly appreciated. FWIW, I'm not the first one struggling [2] with this problem. ;-) Greets Alex [1] https://www.microchip.com/en-us/product/ATSAMA5D27C-D5M#document-table [2] https://community.atmel.com/forum/sama5d2-using-hsic-under-linux
WARNING: multiple messages have this Message-ID (diff)
From: Alexander Dahl <ada@thorsis.com> To: linux-usb@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, rca@thorsis.com Subject: Enable HSIC Host Port on Atmel/Microchip SAMA5D2 Date: Mon, 23 Aug 2021 11:24:35 +0200 [thread overview] Message-ID: <2869763.XZdSvA6Ref@ada> (raw) Hello, for a new embedded board featuring a Microchip SAMA5D2 SoC (64 MiB SiP variant SAMA5D27C-D5M) we connected the third USB host port (HSIC only) with an USB3503 hub chip. This doesn't work out of the box with the Linux kernel currently, because neither the SoC nor the kernel does enable the HSIC interface by default. That SoC has three USB host ports, from the SAMA5D2 Series Datasheet [1] I learned there's a flag in an EHCI register, which has to be set to enable the HSIC interface on port C, the third port. (Section "41.7.14 EHCI: REG08 - HSIC Enable/Disable" of the datasheet.) I suppose that register is vendor specific. The register definitions in '/include/linux/usb/ehci_def.h' do not contain that register. Where would I add that register definition and set that flag in the kernel then? I suppose in the vendor specific ehci driver? That would be 'drivers/usb/host/ehci-atmel.c' right? Since that feature is optional (other boards don't need to turn on hsic on that port), some driver specific new device tree binding would be necessary, right? I suppose that would have to be documented in 'Documentation/ devicetree/bindings/usb/atmel-usb.txt' right? (Or that would have to be converted to yaml first?) Is this the right track? If yes, I'm going to develop patches for this. Otherwise any hint into the right direction are highly appreciated. FWIW, I'm not the first one struggling [2] with this problem. ;-) Greets Alex [1] https://www.microchip.com/en-us/product/ATSAMA5D27C-D5M#document-table [2] https://community.atmel.com/forum/sama5d2-using-hsic-under-linux _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next reply other threads:[~2021-08-23 9:29 UTC|newest] Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-08-23 9:24 Alexander Dahl [this message] 2021-08-23 9:24 ` Enable HSIC Host Port on Atmel/Microchip SAMA5D2 Alexander Dahl 2021-08-23 14:00 ` Alan Stern 2021-08-23 14:00 ` Alan Stern 2021-08-24 6:37 ` [RFC PATCH] USB: host: ehci-atmel: Allow enabling HSIC on SAMA5D2 Alexander Dahl 2021-08-24 6:37 ` Alexander Dahl 2021-08-24 6:45 ` Greg Kroah-Hartman 2021-08-24 6:45 ` Greg Kroah-Hartman 2021-09-02 15:33 ` Nicolas Ferre 2021-09-02 15:33 ` Nicolas Ferre 2021-09-06 7:20 ` Alexander Dahl 2021-09-06 7:20 ` Alexander Dahl
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=2869763.XZdSvA6Ref@ada \ --to=ada@thorsis.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux-usb@vger.kernel.org \ --cc=rca@thorsis.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.