Re: [RFC 00/12] rtwlan: mac80211 driver for Realtek 802.11ac wireless network chips

[Kalle Valo <kvalo@codeaurora.org>]

Tony Chuang <yhchuang@realtek.com> writes:

>> -----Original Message-----
>> From: Kalle Valo [mailto:kvalo@codeaurora.org]
>> Sent: Monday, September 24, 2018 7:05 PM
>> To: Stanislaw Gruszka
>> Cc: Tony Chuang; Larry.Finger@lwfinger.net; linux-wireless@vger.kernel.org;
>> Pkshih; Andy Huang
>> Subject: Re: [RFC 00/12] rtwlan: mac80211 driver for Realtek 802.11ac
>> wireless network chips
>> 
>> Stanislaw Gruszka <sgruszka@redhat.com> writes:
>> 
>> > On Fri, Sep 21, 2018 at 02:03:55PM +0800, yhchuang@realtek.com wrote:
>> >> From: Yan-Hsuan Chuang <yhchuang@realtek.com>
>> >>
>> >> This is a new mac80211 driver for Realtek 802.11ac wireless network chips.
>> >> rtwlan supports 8822BE and 8822CE chips, and will be able to support
>> >> multi-vif combinations in run-time.
>> >>
>> >> For now, only PCI bus is supported, but rtwlan was originally designed
>> >> to optionally support three buses includes USB & SDIO. USB & SDIO
>> modules
>> >> will soon be supported by rtwlan, with configurable core module to fit
>> >> with different bus modules in the same time.
>> >>
>> >> For example, if we choose 8822BE and 8822CU, only PCI & USB modules
>> will
>> >> be selected, built, loaded into kernel. This is one of the major
>> >> difference from rtlwifi, which can only support specific combinations.
>> >>
>> >> Another difference from rtlwifi is that rtwlan is designed to support
>> >> the latest Realtek 802.11ac wireless network chips like 8822B and
>> >> 8822C series. Compared to the earlier chips supported by rtlwifi like
>> >> the 802.11n 8192EE chipset or 802.11ac 8821AE/8812AE chips, newer ICs
>> >> have different MAC & PHY settings, such as new multi-port feature for the
>> >> MAC layer design and Jaguar2/Jaguar3 PHY layer IPs.
>> >>
>> >> Multi-Port feature is also supported under rtwlan's software architecture.
>> >> rtlwifi can only support one vif in the same time, most because of the
>> >> hardware limitations for early chips, hence the original design of it
>> >> also restricts the usage of multi-vif support, so latest chipset seems not
>> >> take advantages from its new MAC engine.
>> >>
>> >> However, rtwlan can run multiple vifs concurrently by holding them on
>> >> hardware ports provided by MAC engine, so we can easily start different
>> >> roles on a single device.
>> >>
>> >> Based on the reasons mentioned before, we implemented rtwlan. It had
>> many
>> >> authors, they are listed here alphabetically:
>> >>
>> >> Ping-Ke Shih <pkshih@realtek.com>
>> >> Tzu-En Huang <tehuang@realtek.com>
>> >> Yan-Hsuan Chuang <yhchuang@realtek.com>
>> >
>> > I didn't do detailed review, but my general impression is very very
>> > positive. New driver looks great!
>> 
>> I also did a quick 10 min look at the driver and indeed in general it
>> looks good.
>> 
>> > Just 2 generic remarks:
>> > - please add MAINTAINERS file entry
>> > - please post a patch or request to remove staging/rtlwifi driver
>> >   since this one is replace for it (8822BE PCI-ID is the same)
>> 
>> Something I noticed:
>> 
>> o Magic numbers (BIT(1) etc) in quite a few places.
>> 
>> o Personally not really fond of "#ifdef LITTLE_ENDIAN" usage, but I
>>   guess we can live with that?
>> 
>> o To me the name "rtwlan" sounds confusing when one compares it with
>>   "rtlwifi". And how would the possible next generation 11ax driver be
>>   then called? As a good example I really like the driver name mt76,
>>   could this one have something similar to make it more descriptive?
>> 
>> I also pushed this to the pending branch on wireless-drivers-next so
>> that kbuild bot can extensively test it.
>
> Yes, we will add MAINTAINER files entry after this driver.
> got accepted into the kernel, or should we include the entry in this patch?

Please update the MAINTAINERS file in this patchset, just in a separate
patch. I can them apply it at the same time as the driver (once it's
ready).

-- 
Kalle Valo