lkml.org 
[lkml]   [2023]   [Oct]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1] i2c: designware: Disable TX_EMPTY irq while waiting for block length byte
On Fri, Sep 29, 2023 at 10:53:56AM +0700, Tam Nguyen wrote:
> During SMBus block data read process, we have seen high interrupt rate
> because of TX_EMPTY irq status while waiting for block length byte (the
> first data byte after the address phase). The interrupt handler does not
> do anything because the internal state is kept as STATUS_WRITE_IN_PROGRESS.
> Hence, we should disable TX_EMPTY irq until I2C DW receives first data

IRQ
DesignWare

> byte from I2C device, then re-enable it.
>
> It takes 0.789 ms for host to receive data length from slave.
> Without the patch, i2c_dw_isr is called 99 times by TX_EMPTY interrupt.

i2c_dw_isr()

> And it is none after applying the patch.

> Cc: stable@vger.kernel.org
> Signed-off-by: Chuong Tran <chuong@os.amperecomputing.com>

Who is this guy? Do you need Co-developed-by tag?

> Signed-off-by: Tam Nguyen <tamnguyenchi@os.amperecomputing.com>

Other than that, agree with Serge's points.

--
With Best Regards,
Andy Shevchenko


\
 
 \ /
  Last update: 2023-10-03 10:58    [W:0.126 / U:0.196 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site