[PATCH 6/7] mmc: bcm2835: Refactor dma_map_sg handling
From: Stefan Wahren <hidden>
Date: 2018-11-11 13:45:29
Also in:
linux-mmc
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, the rest · Maintainers:
Ulf Hansson, Linus Torvalds
There are two variables len within bcm2835_prepare_dma. So rename the result of dma_map_sg to sg_len. While we are at this add a bail out to simplify the following change. Signed-off-by: Stefan Wahren <redacted> --- drivers/mmc/host/bcm2835.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index 2c7589f..c42bdaa 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c@@ -464,7 +464,7 @@ static void bcm2835_transfer_pio(struct bcm2835_host *host) static void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data) { - int len, dir_data, dir_slave; + int sg_len, dir_data, dir_slave; struct dma_async_tx_descriptor *desc = NULL; struct dma_chan *dma_chan;
@@ -510,15 +510,13 @@ void bcm2835_prepare_dma(struct bcm2835_host *host, struct mmc_data *data) &host->dma_cfg_rx : &host->dma_cfg_tx); - len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, - dir_data); + sg_len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len, + dir_data); + if (!sg_len) + return; - if (len > 0) { - desc = dmaengine_prep_slave_sg(dma_chan, data->sg, - len, dir_slave, - DMA_PREP_INTERRUPT | - DMA_CTRL_ACK); - } + desc = dmaengine_prep_slave_sg(dma_chan, data->sg, sg_len, dir_slave, + DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (desc) { desc->callback = bcm2835_dma_complete;
--
2.7.4