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Subject: Re: [PATCH v10] i2c: virtio: add a virtio i2c frontend driver
To:     Wolfram Sang <wsa@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        Linux I2C <linux-i2c@vger.kernel.org>,
        virtualization@lists.linux-foundation.org,
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        conghui.chen@intel.com, kblaiech@mellanox.com,
        jarkko.nikula@linux.intel.com,
        Sergey Semin <Sergey.Semin@baikalelectronics.ru>,
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        Bjorn Andersson <bjorn.andersson@linaro.org>,
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        Viresh Kumar <viresh.kumar@linaro.org>,
        Stefan Hajnoczi <stefanha@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>
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From:   Jie Deng <jie.deng@intel.com>
Message-ID: <4c7f0989-305b-fe4c-63d1-966043c5d2f2@intel.com>
Date:   Tue, 29 Jun 2021 11:04:10 +0800
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On 2021/6/28 22:58, Wolfram Sang wrote:
> If adding support incrementally works for such an interface, this makes
> sense as well.
>
> So, where are we? As I understand, this v10 does not support I2C
> transactions (or I2C_RDWR as you said). But you want to support all
> clients. So, this doesn't match, or?

I hope we can have a minimum working driver get merged first so that we 
can have a base.

The v10 has three remaining problems:

 ??? 1. To remove vi->adap.class = I2C_CLASS_DEPRECATED; (already 
confirmed by Wolfram)

 ??? 2. Use #ifdef CONFIG_PM_SLEEP to replace the "__maybe_unused" 
(already confirmed by Arnd)

 ??? 3. It seems the I2C core takes care of locking already, so is it 
safy to remove "struct mutex lock in struct virtio_i2c"?

 ??????? (Raised by Viresh, still need Wolfram's confirmation)

Regards,

Jie