4.18-stable review patch. If anyone has any objections, please let me know.
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From: Nathan Chancellor natechancellor@gmail.com
[ Upstream commit a1108c7b2efb892350ba6a0e932dfd45622f4e2b ]
Clang warns when one enumerated type is implicitly converted to another.
drivers/spi/spi-ep93xx.c:342:62: warning: implicit conversion from enumeration type 'enum dma_transfer_direction' to different enumeration type 'enum dma_data_direction' [-Wenum-conversion] nents = dma_map_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ ./include/linux/dma-mapping.h:428:58: note: expanded from macro 'dma_map_sg' #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0) ~~~~~~~~~~~~~~~~ ^ drivers/spi/spi-ep93xx.c:348:57: warning: implicit conversion from enumeration type 'enum dma_transfer_direction' to different enumeration type 'enum dma_data_direction' [-Wenum-conversion] dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ ./include/linux/dma-mapping.h:429:62: note: expanded from macro 'dma_unmap_sg' #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0) ~~~~~~~~~~~~~~~~~~ ^ drivers/spi/spi-ep93xx.c:377:56: warning: implicit conversion from enumeration type 'enum dma_transfer_direction' to different enumeration type 'enum dma_data_direction' [-Wenum-conversion] dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~ ./include/linux/dma-mapping.h:429:62: note: expanded from macro 'dma_unmap_sg' #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0) ~~~~~~~~~~~~~~~~~~ ^ 3 warnings generated.
dma_{,un}map_sg expect an enum of type dma_data_direction but this driver uses dma_transfer_direction for everything. Convert the driver to use dma_data_direction for these two functions.
There are two places that strictly require an enum of type dma_transfer_direction: the direction member in struct dma_slave_config and the direction parameter in dmaengine_prep_slave_sg. To avoid using an explicit cast, add a simple function, ep93xx_dma_data_to_trans_dir, to safely map between the two types because they are not 1 to 1 in meaning.
Signed-off-by: Nathan Chancellor natechancellor@gmail.com Reviewed-by: Nick Desaulniers ndesaulniers@google.com Reviewed-by: Mika Westerberg mika.westerberg@linux.intel.com Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/spi/spi-ep93xx.c | 36 +++++++++++++++++++++++++----------- 1 file changed, 25 insertions(+), 11 deletions(-)
--- a/drivers/spi/spi-ep93xx.c +++ b/drivers/spi/spi-ep93xx.c @@ -246,6 +246,19 @@ static int ep93xx_spi_read_write(struct return -EINPROGRESS; }
+static enum dma_transfer_direction +ep93xx_dma_data_to_trans_dir(enum dma_data_direction dir) +{ + switch (dir) { + case DMA_TO_DEVICE: + return DMA_MEM_TO_DEV; + case DMA_FROM_DEVICE: + return DMA_DEV_TO_MEM; + default: + return DMA_TRANS_NONE; + } +} + /** * ep93xx_spi_dma_prepare() - prepares a DMA transfer * @master: SPI master @@ -257,7 +270,7 @@ static int ep93xx_spi_read_write(struct */ static struct dma_async_tx_descriptor * ep93xx_spi_dma_prepare(struct spi_master *master, - enum dma_transfer_direction dir) + enum dma_data_direction dir) { struct ep93xx_spi *espi = spi_master_get_devdata(master); struct spi_transfer *xfer = master->cur_msg->state; @@ -277,9 +290,9 @@ ep93xx_spi_dma_prepare(struct spi_master buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
memset(&conf, 0, sizeof(conf)); - conf.direction = dir; + conf.direction = ep93xx_dma_data_to_trans_dir(dir);
- if (dir == DMA_DEV_TO_MEM) { + if (dir == DMA_FROM_DEVICE) { chan = espi->dma_rx; buf = xfer->rx_buf; sgt = &espi->rx_sgt; @@ -343,7 +356,8 @@ ep93xx_spi_dma_prepare(struct spi_master if (!nents) return ERR_PTR(-ENOMEM);
- txd = dmaengine_prep_slave_sg(chan, sgt->sgl, nents, dir, DMA_CTRL_ACK); + txd = dmaengine_prep_slave_sg(chan, sgt->sgl, nents, conf.direction, + DMA_CTRL_ACK); if (!txd) { dma_unmap_sg(chan->device->dev, sgt->sgl, sgt->nents, dir); return ERR_PTR(-ENOMEM); @@ -360,13 +374,13 @@ ep93xx_spi_dma_prepare(struct spi_master * unmapped. */ static void ep93xx_spi_dma_finish(struct spi_master *master, - enum dma_transfer_direction dir) + enum dma_data_direction dir) { struct ep93xx_spi *espi = spi_master_get_devdata(master); struct dma_chan *chan; struct sg_table *sgt;
- if (dir == DMA_DEV_TO_MEM) { + if (dir == DMA_FROM_DEVICE) { chan = espi->dma_rx; sgt = &espi->rx_sgt; } else { @@ -381,8 +395,8 @@ static void ep93xx_spi_dma_callback(void { struct spi_master *master = callback_param;
- ep93xx_spi_dma_finish(master, DMA_MEM_TO_DEV); - ep93xx_spi_dma_finish(master, DMA_DEV_TO_MEM); + ep93xx_spi_dma_finish(master, DMA_TO_DEVICE); + ep93xx_spi_dma_finish(master, DMA_FROM_DEVICE);
spi_finalize_current_transfer(master); } @@ -392,15 +406,15 @@ static int ep93xx_spi_dma_transfer(struc struct ep93xx_spi *espi = spi_master_get_devdata(master); struct dma_async_tx_descriptor *rxd, *txd;
- rxd = ep93xx_spi_dma_prepare(master, DMA_DEV_TO_MEM); + rxd = ep93xx_spi_dma_prepare(master, DMA_FROM_DEVICE); if (IS_ERR(rxd)) { dev_err(&master->dev, "DMA RX failed: %ld\n", PTR_ERR(rxd)); return PTR_ERR(rxd); }
- txd = ep93xx_spi_dma_prepare(master, DMA_MEM_TO_DEV); + txd = ep93xx_spi_dma_prepare(master, DMA_TO_DEVICE); if (IS_ERR(txd)) { - ep93xx_spi_dma_finish(master, DMA_DEV_TO_MEM); + ep93xx_spi_dma_finish(master, DMA_FROM_DEVICE); dev_err(&master->dev, "DMA TX failed: %ld\n", PTR_ERR(txd)); return PTR_ERR(txd); }