From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Brandewie Subject: Re: [PATCH 06/11] spi-dw: Force error on out of range chip select. Date: Wed, 22 Jun 2011 21:13:38 -0700 Message-ID: <4E02BD72.8040007@gmail.com> References: <1308794413-11069-1-git-send-email-dirk.brandewie@gmail.com> <1308794413-11069-7-git-send-email-dirk.brandewie@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, spi-devel-general@lists.sourceforge.net To: Grant Likely Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org On 06/22/2011 08:51 PM, Grant Likely wrote: > On Wed, Jun 22, 2011 at 8:00 PM, wrote: >> From: Dirk Brandewie >> >> BUG_ON() if the selected chip select is out of range. >> >> Signed-off-by: Dirk Brandewie >> --- >> drivers/spi/spi-dw.h | 3 +-- >> 1 files changed, 1 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h >> index 860bc34..3fa4c13 100644 >> --- a/drivers/spi/spi-dw.h >> +++ b/drivers/spi/spi-dw.h >> @@ -178,8 +178,7 @@ static inline void spi_dw_set_clk(struct spi_dw *dws, u16 div) >> >> static inline void spi_dw_chip_sel(struct spi_dw *dws, u16 cs) >> { >> - if (cs> dws->num_cs) >> - return; >> + BUG_ON(cs>= dws->master->num_chipselect); > > BUG is rather an over-reaction. The transfer should be rejected if > the cs# is invalid, and a warning message is appropriate, but BUG() is > too extreme. This is extreme I agree, the current driver will fail silently if an out of range chip select is requested. We can drop this one for now and I will put a proper check in probe/init so we won't get here. > > g.