Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1246521

Re: [RFC][PATCH] spi: Setup the master controller driver before setting the chipselect

From Andy Shevchenko <andy.shevchenko@gmail.com>
Newsgroups linux.kernel
Subject Re: [RFC][PATCH] spi: Setup the master controller driver before setting the chipselect
Date 2015-10-14 13:10 +0200
Message-ID <qjs6t-52j-5@gated-at.bofh.it> (permalink)
References <qiSw1-2oF-5@gated-at.bofh.it> <qiSw2-2oF-21@gated-at.bofh.it> <qjqR5-31B-41@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


+Cc: Jarkko to see from spi-pxa2xx prospective

On Wed, Oct 14, 2015 at 12:47 PM, Ivan T. Ivanov <iivanov.xz@gmail.com> wrote:
> Adding Andy.
>
>
>> On Oct 13, 2015, at 12:01 AM, Franklin S Cooper Jr <fcooper@ti.com> wrote:
>>
>> Some devices depend on the master controller driver setup function being
>> called before calling any chipselect functions.
>>
>> Insure that this is done otherwise uninitialized structures may be
>> accessed causing a kernel panic.

As far as I understand my concern should be about spi-dw driver.

So, I have just tested yesterday's linux-next with and without
proposed patch. Works for me:
Tested-by: Andy Shevchenko <andy.shevchenko@gmail.com>

>>
>> Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
>> ---
>> drivers/spi/spi.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
>> index 38006cc..9374d82 100644
>> --- a/drivers/spi/spi.c
>> +++ b/drivers/spi/spi.c
>> @@ -2053,11 +2053,11 @@ int spi_setup(struct spi_device *spi)
>>       if (!spi->max_speed_hz)
>>               spi->max_speed_hz = spi->master->max_speed_hz;
>>
>> -     spi_set_cs(spi, false);
>> -
>>       if (spi->master->setup)
>>               status = spi->master->setup(spi);
>>
>> +     spi_set_cs(spi, false);
>> +
>>       dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
>>                       (int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
>>                       (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",
>> --
>> 2.6.1
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-spi" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>



-- 
With Best Regards,
Andy Shevchenko
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[RFC] spi: Switch call order of spi master setup and spi_set_cs Franklin S Cooper Jr <fcooper@ti.com> - 2015-10-12 23:10 +0200
  [RFC][PATCH] spi: Setup the master controller driver before setting the chipselect Franklin S Cooper Jr <fcooper@ti.com> - 2015-10-12 23:10 +0200
    Re: [RFC][PATCH] spi: Setup the master controller driver before setting the chipselect "Ivan T. Ivanov" <iivanov.xz@gmail.com> - 2015-10-14 11:50 +0200
      Re: [RFC][PATCH] spi: Setup the master controller driver before  setting the chipselect Andy Shevchenko <andy.shevchenko@gmail.com> - 2015-10-14 13:10 +0200
        Re: [RFC][PATCH] spi: Setup the master controller driver before  setting the chipselect Heiner Kallweit <hkallweit1@gmail.com> - 2015-10-14 13:50 +0200
          Re: [RFC][PATCH] spi: Setup the master controller driver before  setting the chipselect "Franklin S Cooper Jr." <fcooper@ti.com> - 2015-10-15 23:00 +0200
  Re: [RFC] spi: Switch call order of spi master setup and spi_set_cs Mark Brown <broonie@kernel.org> - 2015-10-13 14:20 +0200
    Re: [RFC] spi: Switch call order of spi master setup and spi_set_cs "Franklin S Cooper Jr." <fcooper@ti.com> - 2015-10-13 16:10 +0200

csiph-web