From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dirk Brandewie Subject: Re: [PATCH 11/11] spi-dw: remove noop else clause Date: Wed, 22 Jun 2011 20:13:45 -0700 Message-ID: <4E02AF69.2090800@gmail.com> References: <1308794413-11069-1-git-send-email-dirk.brandewie@gmail.com> <1308794413-11069-12-git-send-email-dirk.brandewie@gmail.com> <20110623104756.1d1c8da4@feng-i7> 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: Feng Tang Return-path: In-Reply-To: <20110623104756.1d1c8da4@feng-i7> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org On 06/22/2011 07:47 PM, Feng Tang wrote: > On Thu, 23 Jun 2011 10:00:13 +0800 > "dirk.brandewie@gmail.com" wrote: > >> From: Dirk Brandewie >> >> The value of spi->bits_per_word is checked on function entry to be 8 >> or 16. The else clause has no meaning since it can never be reached. >> >> Signed-off-by: Dirk Brandewie >> --- >> drivers/spi/spi-dw.c | 9 +++------ >> 1 files changed, 3 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c >> index 7b3f607..5ddd45f 100644 >> --- a/drivers/spi/spi-dw.c >> +++ b/drivers/spi/spi-dw.c >> @@ -667,17 +667,14 @@ static int spi_dw_setup(struct spi_device *spi) >> chip->enable_dma = chip_info->enable_dma; >> } >> >> - if (spi->bits_per_word<= 8) { >> + if (spi->bits_per_word == 8) { >> chip->n_bytes = 1; >> chip->dma_width = 1; >> - } else if (spi->bits_per_word<= 16) { >> + } else if (spi->bits_per_word == 16) { >> chip->n_bytes = 2; >> chip->dma_width = 2; >> - } else { >> - /* Never take>16b case for DW SPIC */ >> - dev_err(&spi->dev, "invalid wordsize\n"); >> - return -EINVAL; >> } > > These "else" case is used to ban the slave spi devices which > try to use 32 bits per word mode. This is like to tell those > spi devices with 32 bpw capability "we don't support 32b, pls > change" The function has the prerequisite code: if (spi->bits_per_word != 8 && spi->bits_per_word != 16) return -EINVAL; at the begining of the function so we will never be able to reach the else clause that is being removed. > >> + >> chip->bits_per_word = spi->bits_per_word; >> >> chip->speed_hz = spi->max_speed_hz;