From 2bca34455b257d75080d87e800ae14afe49001bf Mon Sep 17 00:00:00 2001 From: Vignesh R Date: Tue, 11 Apr 2017 17:22:24 +0530 Subject: [PATCH] spi: Add can_dma like interface for spi_flash_read Add an interface analogous to ->can_dma() for spi_flash_read() interface. This will enable SPI controller drivers to inform SPI core when not to do DMA mappings. Signed-off-by: Vignesh R Signed-off-by: Mark Brown --- drivers/spi/spi.c | 2 +- include/linux/spi/spi.h | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 656dd3e3220c..5e1bb43b8a8f 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2811,7 +2811,7 @@ int spi_flash_read(struct spi_device *spi, mutex_lock(&master->bus_lock_mutex); mutex_lock(&master->io_mutex); - if (master->dma_rx) { + if (master->dma_rx && master->spi_flash_can_dma(spi, msg)) { rx_dev = master->dma_rx->device->dev; ret = spi_map_buf(master, rx_dev, &msg->rx_sg, msg->buf, msg->len, diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 75c6bd0ac605..cd8ae65568e3 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -375,6 +375,8 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @unprepare_message: undo any work done by prepare_message(). * @spi_flash_read: to support spi-controller hardwares that provide * accelerated interface to read from flash devices. + * @spi_flash_can_dma: analogous to can_dma() interface, but for + * controllers implementing spi_flash_read. * @flash_read_supported: spi device supports flash read * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS * number. Any individual value may be -ENOENT for CS lines that @@ -538,6 +540,8 @@ struct spi_master { struct spi_message *message); int (*spi_flash_read)(struct spi_device *spi, struct spi_flash_read_message *msg); + bool (*spi_flash_can_dma)(struct spi_device *spi, + struct spi_flash_read_message *msg); bool (*flash_read_supported)(struct spi_device *spi); /* -- 2.45.2