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

Groups > linux.kernel > #1645766

Re: [PATCH 1/1] spi: imx: fix issue when tx_buf or rx_buf is NULL

Show all headers | View raw

[Multipart message — attachments visible in raw view] - view raw

On Fri, May 19, 2017 at 04:15:01PM +0300, Andy Shevchenko wrote:
> On Fri, May 19, 2017 at 3:45 PM, Chris Ruehl <chris.ruehl@gtsys.com.hk> wrote:

> > But I think we missing something here. We return from a void function()
> > so the error keeps hidden. The root cause is calling this functions with a
> > NULL pointer. See if you can fix this by find the caller and check if the
> > parameter hand over are valid.

> AFAIU some SPI controllers can have half-duplex protocol, in which the
> second buffer might be absent.

Yes, it's not only perfectly valid but actually the common case for only
one direction of data to be meaningful in SPI so the majority of
controllers don't require data to be transferred in both directions, it
would just add bus overhead.

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

Thread

[PATCH 1/1] spi: imx: fix issue when tx_buf or rx_buf is NULL <jiada_wang@mentor.com> - 2017-05-18 12:10 +0200
  Re: [PATCH 1/1] spi: imx: fix issue when tx_buf or rx_buf is NULL Chris Ruehl <chris.ruehl@gtsys.com.hk> - 2017-05-19 15:00 +0200
    Re: [PATCH 1/1] spi: imx: fix issue when tx_buf or rx_buf is NULL Andy Shevchenko <andy.shevchenko@gmail.com> - 2017-05-19 15:20 +0200
      Re: [PATCH 1/1] spi: imx: fix issue when tx_buf or rx_buf is NULL Mark Brown <broonie@kernel.org> - 2017-05-19 19:00 +0200
  Applied "spi: imx: fix issue when tx_buf or rx_buf is NULL" to the spi tree Mark Brown <broonie@kernel.org> - 2017-05-19 19:10 +0200

csiph-web