From 43dba9f3f98c2b184a19f856f06fe22817bfd9e0 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Fri, 22 May 2020 03:07:51 +0300 Subject: [PATCH] spi: dw: Enable interrupts in accordance with DMA xfer mode It's pointless to track the Tx overrun interrupts if Rx-only SPI transfer is issued. Similarly there is no need in handling the Rx overrun/underrun interrupts if Tx-only SPI transfer is executed. So lets unmask the interrupts only if corresponding SPI transactions are implied. Co-developed-by: Georgy Vlasov Signed-off-by: Georgy Vlasov Signed-off-by: Serge Semin Cc: Ramil Zaripov Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Arnd Bergmann Cc: Andy Shevchenko Cc: Rob Herring Cc: linux-mips@vger.kernel.org Cc: devicetree@vger.kernel.org Link: https://lore.kernel.org/r/20200522000806.7381-3-Sergey.Semin@baikalelectronics.ru Signed-off-by: Mark Brown --- drivers/spi/spi-dw-mid.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-dw-mid.c b/drivers/spi/spi-dw-mid.c index f9757a3..1578dfe 100644 --- a/drivers/spi/spi-dw-mid.c +++ b/drivers/spi/spi-dw-mid.c @@ -243,19 +243,23 @@ static struct dma_async_tx_descriptor *dw_spi_dma_prepare_rx(struct dw_spi *dws, static int mid_spi_dma_setup(struct dw_spi *dws, struct spi_transfer *xfer) { - u16 dma_ctrl = 0; + u16 imr = 0, dma_ctrl = 0; dw_writel(dws, DW_SPI_DMARDLR, 0xf); dw_writel(dws, DW_SPI_DMATDLR, 0x10); - if (xfer->tx_buf) + if (xfer->tx_buf) { dma_ctrl |= SPI_DMA_TDMAE; - if (xfer->rx_buf) + imr |= SPI_INT_TXOI; + } + if (xfer->rx_buf) { dma_ctrl |= SPI_DMA_RDMAE; + imr |= SPI_INT_RXUI | SPI_INT_RXOI; + } dw_writel(dws, DW_SPI_DMACR, dma_ctrl); /* Set the interrupt mask */ - spi_umask_intr(dws, SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI); + spi_umask_intr(dws, imr); dws->transfer_handler = dma_transfer; -- 2.7.4