linux-input.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Enrik Berkhan <Enrik.Berkhan@inka.de>
To: Michael Zaidman <michael.zaidman@gmail.com>
Cc: jikos@kernel.org, linux-kernel@vger.kernel.org,
	linux-input@vger.kernel.org,
	Guillaume Champagne <champagne.guillaume.c@gmail.com>
Subject: Re: [PATCH v2 5/7] HID: ft260: improve i2c large reads performance
Date: Wed, 05 Oct 2022 20:19:15 +0200	[thread overview]
Message-ID: <6ebd7f9424e43c70af4ada9fe5bf616d1a112bcc.camel@inka.de> (raw)
In-Reply-To: <Yz2V+pT/2AmGvE7k@michael-VirtualBox>

Hi Michael,

On Wed, 2022-10-05 at 17:34 +0300, Michael Zaidman wrote:
> On Tue, Oct 04, 2022 at 08:15:56PM +0200, Enrik Berkhan wrote:
> > As the ft260 can pack up to 60 bytes into one report, would it make
> > sense to use a multiple-of-60 size (120 or 180)? Might reduce overhead
> > by another tiny bit ...
> > 
> > Cheers,
> > Enrik
> > 
> The size of the Read IO to perform is given to the driver by the upper
> layer. So it's up to him how to align the IO request size.
> 
> When we read from the EEPROM, we want to issue the read requests with
> EEPROM page size granularity. The I2C EEPROMs page sizes are usually a
> power of 2 aligned.

Understood! I only thought about the HID report sizes. With EEPROMs
etc. in mind, it makes perfect sense to prefer power of 2 sizes.

Thanks for also providing the test results.

Cheers,
Enrik



  reply	other threads:[~2022-10-05 18:19 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-28 14:48 [PATCH v2 0/7] HID: ft260: fixes and performance improvements Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 1/7] HID: ft260: ft260_xfer_status routine cleanup Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 2/7] HID: ft260: improve i2c write performance Michael Zaidman
2022-09-28 15:50   ` David Laight
2022-09-28 20:27     ` Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 3/7] HID: ft260: support i2c writes larger than HID report size Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 4/7] HID: ft260: support i2c reads greater " Michael Zaidman
2022-10-04 18:11   ` Enrik Berkhan
2022-10-05 14:50     ` Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 5/7] HID: ft260: improve i2c large reads performance Michael Zaidman
2022-10-04 18:15   ` Enrik Berkhan
2022-10-05 14:34     ` Michael Zaidman
2022-10-05 18:19       ` Enrik Berkhan [this message]
2022-09-28 14:48 ` [PATCH v2 6/7] HID: ft260: do not populate /dev/hidraw device Michael Zaidman
2022-09-28 14:48 ` [PATCH v2 7/7] HID: ft260: skip unexpected HID input reports Michael Zaidman

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=6ebd7f9424e43c70af4ada9fe5bf616d1a112bcc.camel@inka.de \
    --to=enrik.berkhan@inka.de \
    --cc=champagne.guillaume.c@gmail.com \
    --cc=jikos@kernel.org \
    --cc=linux-input@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=michael.zaidman@gmail.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: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).