diff options
| -rw-r--r-- | recipes-kernel/linux/linux-3.12.27/linux-3.12-spi-atmel-dma-min.patch | 18 | ||||
| -rw-r--r-- | recipes-kernel/linux/linux-3.12.27/mtcdt/defconfig | 2 | ||||
| -rw-r--r-- | recipes-kernel/linux/linux_3.12.27.bb | 3 |
3 files changed, 21 insertions, 2 deletions
diff --git a/recipes-kernel/linux/linux-3.12.27/linux-3.12-spi-atmel-dma-min.patch b/recipes-kernel/linux/linux-3.12.27/linux-3.12-spi-atmel-dma-min.patch new file mode 100644 index 0000000..4aba504 --- /dev/null +++ b/recipes-kernel/linux/linux-3.12.27/linux-3.12-spi-atmel-dma-min.patch @@ -0,0 +1,18 @@ +Index: linux-3.12.27/drivers/spi/spi-atmel.c +=================================================================== +--- linux-3.12.27.orig/drivers/spi/spi-atmel.c ++++ linux-3.12.27/drivers/spi/spi-atmel.c +@@ -187,7 +187,12 @@ + /* use PIO for small transfers, avoiding DMA setup/teardown overhead and + * cache operations; better heuristics consider wordsize and bitrate. + */ +-#define DMA_MIN_BYTES 16 ++ ++/* MTS: set DMA_MIN_BYTES=0 to use DMA all the time due to Rx buffer issues ++ * when switching between smaller PIO and larger DMA transfers ++ * https://lkml.org/lkml/2013/10/21/534 ++ */ ++#define DMA_MIN_BYTES 0 + + struct atmel_spi_dma { + struct dma_chan *chan_rx; diff --git a/recipes-kernel/linux/linux-3.12.27/mtcdt/defconfig b/recipes-kernel/linux/linux-3.12.27/mtcdt/defconfig index 8950cdd..e0476e8 100644 --- a/recipes-kernel/linux/linux-3.12.27/mtcdt/defconfig +++ b/recipes-kernel/linux/linux-3.12.27/mtcdt/defconfig @@ -1425,7 +1425,7 @@ CONFIG_SPI_MASTER=y # SPI Master Controller Drivers # # CONFIG_SPI_ALTERA is not set -CONFIG_SPI_ATMEL=y +CONFIG_SPI_ATMEL=m # CONFIG_SPI_BITBANG is not set # CONFIG_SPI_GPIO is not set # CONFIG_SPI_FSL_SPI is not set diff --git a/recipes-kernel/linux/linux_3.12.27.bb b/recipes-kernel/linux/linux_3.12.27.bb index eb6029c..53ee211 100644 --- a/recipes-kernel/linux/linux_3.12.27.bb +++ b/recipes-kernel/linux/linux_3.12.27.bb @@ -2,7 +2,7 @@ inherit kernel # mts class to build dtb and append to kernel image inherit linux-append-dtb -PR = "r8" +PR = "r9" LICENSE = "GPLv2" LIC_FILES_CHKSUM = "file://COPYING;md5=d7810fab7487fb0aad327b76f1be7cd7" @@ -23,6 +23,7 @@ COMMON_PATCHES = " \ file://linux-3.12.27-option-telit.patch \ file://linux-3.12-cdc-acm-ignore-exar-devices.patch \ file://linux-3.12-release-rfcomm-port-fix.patch \ + file://linux-3.12-spi-atmel-dma-min.patch \ " SRC_URI_append_mtcdt = "\ |