From 01d7aafb3fbaafe2403780ef9ed497b3289ab1b9 Mon Sep 17 00:00:00 2001 From: "Chew, Chiau Ee" Date: Fri, 6 Jun 2014 01:45:09 +0800 Subject: spi/pxa2xx: change default supported DMA burst size to 1 This is to fix the SPI DMA transfer failure for speed less than 1M. If using current DMA burst size setting (16), the Rx data bytes are invalid due to each data byte is multiplied according to the burst size setting. Let's said supposedly we shall receive the following 18 bytes of data: 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 Instead, the data bytes received consist of "16 bytes of '01' + 2 bytes of '02'" : 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 02 02 Signed-off-by: Chew, Chiau Ee Acked-by: Mika Westerberg Signed-off-by: Mark Brown --- drivers/spi/spi-pxa2xx-dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/spi') diff --git a/drivers/spi/spi-pxa2xx-dma.c b/drivers/spi/spi-pxa2xx-dma.c index f6759dc..c41ff14 100644 --- a/drivers/spi/spi-pxa2xx-dma.c +++ b/drivers/spi/spi-pxa2xx-dma.c @@ -368,7 +368,7 @@ int pxa2xx_spi_set_dma_burst_and_threshold(struct chip_data *chip, * otherwise we use the default. Also we use the default FIFO * thresholds for now. */ - *burst_code = chip_info ? chip_info->dma_burst_size : 16; + *burst_code = chip_info ? chip_info->dma_burst_size : 1; *threshold = SSCR1_RxTresh(RX_THRESH_DFLT) | SSCR1_TxTresh(TX_THRESH_DFLT); -- cgit v1.1