From dcb880cb8518b79f900106421510275b7a87a73c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Thu, 8 Dec 2016 10:39:22 +0100 Subject: [PATCH] spi: mvebu: only read from bus when data is needed MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This optimization reduced the time to transfer 40 MB at 50 MHz from 214 seconds to 203 seconds. Signed-off-by: Uwe Kleine-König Signed-off-by: Sascha Hauer --- drivers/spi/mvebu_spi.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/spi/mvebu_spi.c b/drivers/spi/mvebu_spi.c index 63d8083b2..35a0c002a 100644 --- a/drivers/spi/mvebu_spi.c +++ b/drivers/spi/mvebu_spi.c @@ -278,12 +278,12 @@ static int mvebu_spi_do_transfer(struct spi_device *spi, return ret; } - data = readl(priv->base + SPI_DATA_IN); - - if (rxdata) + if (rxdata) { + data = readl(priv->base + SPI_DATA_IN); *rxdata++ = (data & 0xff); - if (rxdata && priv->data16) - *rxdata++ = (data >> 8) & 0xff; + if (priv->data16) + *rxdata++ = (data >> 8) & 0xff; + } } return 0;