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From: s.hauer@pengutronix.de (Sascha Hauer)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 6/9] spi: imx: remove unnecessary bit clearing in mx51_ecspi_config
Date: Fri, 4 Mar 2016 12:47:37 +0100	[thread overview]
Message-ID: <20160304114737.GE21869@pengutronix.de> (raw)
In-Reply-To: <56D968DF.7000007@mentor.com>

On Fri, Mar 04, 2016 at 12:52:15PM +0200, Vladimir Zapolskiy wrote:
> Hi Sascha,
> 
> On 24.02.2016 10:20, Sascha Hauer wrote:
> > This reverts patch 1476253cef (spi: imx: fix ecspi mode setup)
> > The patch tried to fix something by clearing bits in the cfg variable,
> > but cfg is initialized to zero on function entry. There are no bits to
> > clear.
> > 
> > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> 
> I believe here the expected fix should be
> 
> ----8<----
> 
> diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
> index 6a4ff27..9c9bae0 100644
> --- a/drivers/spi/spi-imx.c
> +++ b/drivers/spi/spi-imx.c
> @@ -316,9 +316,10 @@ static void __maybe_unused mx51_ecspi_trigger(struct
> spi_imx_data *spi_imx)
>  static int __maybe_unused mx51_ecspi_config(struct spi_imx_data *spi_imx,
>  		struct spi_imx_config *config)
>  {
> -	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, cfg = 0, dma = 0;
> +	u32 ctrl = MX51_ECSPI_CTRL_ENABLE, dma = 0;
>  	u32 tx_wml_cfg, rx_wml_cfg, rxt_wml_cfg;
>  	u32 clk = config->speed_hz, delay, reg;
> +	u32 cfg = readl(spi_imx->base + MX51_ECSPI_CONFIG);
> 

With this change applied we would indeed have to clear and not only set the bits,
but why would we do this?

Sascha

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  reply	other threads:[~2016-03-04 11:47 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-24  8:20 [PATCH v4] i.MX SPI DMA cleanup Sascha Hauer
2016-02-24  8:20 ` [PATCH 1/9] spi: imx: drop fallback to PIO Sascha Hauer
2016-02-24  8:20 ` [PATCH 2/9] spi: imx: initialize usedma earlier Sascha Hauer
2016-02-24  8:20 ` [PATCH 3/9] spi: imx: drop unnecessary read/modify/write Sascha Hauer
2016-02-24  8:20 ` [PATCH 4/9] spi: imx: drop unncessary dma_is_inited variable Sascha Hauer
2016-02-24  8:20 ` [PATCH 5/9] spi: imx: add support for all SPI word width for DMA Sascha Hauer
2016-03-04 10:39   ` Vladimir Zapolskiy
2016-02-24  8:20 ` [PATCH 6/9] spi: imx: remove unnecessary bit clearing in mx51_ecspi_config Sascha Hauer
2016-03-04 10:52   ` Vladimir Zapolskiy
2016-03-04 11:47     ` Sascha Hauer [this message]
2016-03-04 12:06       ` Vladimir Zapolskiy
2016-03-07  7:54         ` Sascha Hauer
2016-02-24  8:20 ` [PATCH 7/9] spi: imx: make some register defines simpler Sascha Hauer
2016-02-24  8:20 ` [PATCH 8/9] spi: imx: set MX51_ECSPI_CTRL_SMC bit in setup function Sascha Hauer
2016-02-24  8:20 ` [PATCH 9/9] spi: imx: drop bogus tests for rx/tx bufs in DMA transfer Sascha Hauer
  -- strict thread matches above, loose matches on Subject: below --
2016-02-23  9:23 [PATCH v3] i.MX SPI DMA cleanup Sascha Hauer
2016-02-23  9:23 ` [PATCH 6/9] spi: imx: remove unnecessary bit clearing in mx51_ecspi_config Sascha Hauer

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