From: Lei Yu <yulei.sh@bytedance.com>
To: Oskar Senft <osk@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
John Wang <wangzhiqiang.bj@bytedance.com>,
Lotus Xu <xuxiaohan@bytedance.com>,
Yong Li <yong.b.li@linux.intel.com>,
Vernon Mauery <vernon.mauery@linux.intel.com>,
Joel Stanley <joel@jms.id.au>, Andrew Jeffery <andrew@aj.id.au>,
Jonathan Corbet <corbet@lwn.net>,
Derek Kiernan <derek.kiernan@xilinx.com>,
Dragan Cvetic <dragan.cvetic@xilinx.com>,
Arnd Bergmann <arnd@arndb.de>,
"moderated list:ARM/ASPEED MACHINE SUPPORT"
<linux-arm-kernel@lists.infradead.org>,
"moderated list:ARM/ASPEED MACHINE SUPPORT"
<linux-aspeed@lists.ozlabs.org>,
open list <linux-kernel@vger.kernel.org>,
"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>
Subject: Re: [External] Re: [PATCH 1/3] misc: aspeed: Add Aspeed UART routing control driver.
Date: Fri, 11 Dec 2020 10:06:05 +0800 [thread overview]
Message-ID: <CAGm54UFJt2PHJThigVYLrgKqBz7rNF-vWYFJ5wykBx+GPjzihw@mail.gmail.com> (raw)
In-Reply-To: <CABoTLcSiCsASu_prfxH_sZrm-njcYzkcvrrpS1envj7QvxYtNA@mail.gmail.com>
On Thu, Dec 10, 2020 at 8:33 PM Oskar Senft <osk@google.com> wrote:
>
> The purpose of this driver is to allow manipulation of the UART routing at runtime. Setting the routing in the DTS would obviously not allow that.
>
> From what I remember, I used am existing unrelated driver as template. Apologies for using the wrong APIs - I literally just followed what I had seen elsewhere.
>
> Since posting this driver, we found that while it solved our initial use case, that use case has evolved. We're now using Aspeed's VUART where bytes are routed "manually" (i.e. copied between devices) rather than in hardware. So I don't need this driver anymore.
>
> If it's still useful to anyone, please take ownership and modify it as needed to be able to submit it. I'm still happy to keep an eye on it and help explain its purpose.
>
The driver is useful for our system, and it's used in intel-openbmc as well.
We (John and I work for the same employer) have the chance to use
Andrew Jefery's ["bmc-misc" driver][1] to configure the various
registers in dts to setup the UART routing, but that driver was not
accepted by upstream.
So we end up sending this patch here for upstream's comment.
If it's considered not a good option, we will have to keep it downstream.
[1] https://lore.kernel.org/openbmc/20180711053122.30773-1-andrew@aj.id.au/
--
BRs,
Lei YU
WARNING: multiple messages have this Message-ID (diff)
From: Lei Yu <yulei.sh@bytedance.com>
To: Oskar Senft <osk@google.com>
Cc: "moderated list:ARM/ASPEED MACHINE SUPPORT"
<linux-aspeed@lists.ozlabs.org>, Arnd Bergmann <arnd@arndb.de>,
Jonathan Corbet <corbet@lwn.net>,
Andrew Jeffery <andrew@aj.id.au>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Dragan Cvetic <dragan.cvetic@xilinx.com>,
"open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
Yong Li <yong.b.li@linux.intel.com>,
open list <linux-kernel@vger.kernel.org>,
John Wang <wangzhiqiang.bj@bytedance.com>,
Joel Stanley <joel@jms.id.au>,
Vernon Mauery <vernon.mauery@linux.intel.com>,
Derek Kiernan <derek.kiernan@xilinx.com>,
Lotus Xu <xuxiaohan@bytedance.com>,
"moderated list:ARM/ASPEED MACHINE SUPPORT"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [External] Re: [PATCH 1/3] misc: aspeed: Add Aspeed UART routing control driver.
Date: Fri, 11 Dec 2020 10:06:05 +0800 [thread overview]
Message-ID: <CAGm54UFJt2PHJThigVYLrgKqBz7rNF-vWYFJ5wykBx+GPjzihw@mail.gmail.com> (raw)
In-Reply-To: <CABoTLcSiCsASu_prfxH_sZrm-njcYzkcvrrpS1envj7QvxYtNA@mail.gmail.com>
On Thu, Dec 10, 2020 at 8:33 PM Oskar Senft <osk@google.com> wrote:
>
> The purpose of this driver is to allow manipulation of the UART routing at runtime. Setting the routing in the DTS would obviously not allow that.
>
> From what I remember, I used am existing unrelated driver as template. Apologies for using the wrong APIs - I literally just followed what I had seen elsewhere.
>
> Since posting this driver, we found that while it solved our initial use case, that use case has evolved. We're now using Aspeed's VUART where bytes are routed "manually" (i.e. copied between devices) rather than in hardware. So I don't need this driver anymore.
>
> If it's still useful to anyone, please take ownership and modify it as needed to be able to submit it. I'm still happy to keep an eye on it and help explain its purpose.
>
The driver is useful for our system, and it's used in intel-openbmc as well.
We (John and I work for the same employer) have the chance to use
Andrew Jefery's ["bmc-misc" driver][1] to configure the various
registers in dts to setup the UART routing, but that driver was not
accepted by upstream.
So we end up sending this patch here for upstream's comment.
If it's considered not a good option, we will have to keep it downstream.
[1] https://lore.kernel.org/openbmc/20180711053122.30773-1-andrew@aj.id.au/
--
BRs,
Lei YU
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next prev parent reply other threads:[~2020-12-11 2:07 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-10 9:28 [PATCH 1/3] misc: aspeed: Add Aspeed UART routing control driver John Wang
2020-12-10 9:28 ` John Wang
2020-12-10 9:43 ` Greg Kroah-Hartman
2020-12-10 9:43 ` Greg Kroah-Hartman
2020-12-10 10:06 ` [External] " John Wang
2020-12-10 10:06 ` John Wang
2020-12-10 10:30 ` Greg Kroah-Hartman
2020-12-10 10:30 ` Greg Kroah-Hartman
[not found] ` <CABoTLcSiCsASu_prfxH_sZrm-njcYzkcvrrpS1envj7QvxYtNA@mail.gmail.com>
2020-12-11 2:06 ` Lei Yu [this message]
2020-12-11 2:06 ` Lei Yu
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