From 16b90dd94d3f88b9f43cc06228d2b64d32225e5d Mon Sep 17 00:00:00 2001 From: Gustavo Pimentel Date: Thu, 18 Feb 2021 20:04:01 +0100 Subject: dmaengine: dw-edma: Improve number of channels check It was added some extra checks to ensure that the driver doesn't try to use more DMA channels than actually are available in hardware. Signed-off-by: Gustavo Pimentel Link: https://lore.kernel.org/r/cfb2b0a4f97ae9dc83ebe5ea59d6a51d69ea3654.1613674948.git.gustavo.pimentel@synopsys.com Signed-off-by: Vinod Koul --- drivers/dma/dw-edma/dw-edma-core.c | 21 +++++++++------------ drivers/dma/dw-edma/dw-edma-core.h | 2 ++ 2 files changed, 11 insertions(+), 12 deletions(-) (limited to 'drivers') diff --git a/drivers/dma/dw-edma/dw-edma-core.c b/drivers/dma/dw-edma/dw-edma-core.c index 1227a3ed45aa..cc391070c1bf 100644 --- a/drivers/dma/dw-edma/dw-edma-core.c +++ b/drivers/dma/dw-edma/dw-edma-core.c @@ -914,19 +914,16 @@ int dw_edma_probe(struct dw_edma_chip *chip) raw_spin_lock_init(&dw->lock); - if (!dw->wr_ch_cnt) { - /* Find out how many write channels are supported by hardware */ - dw->wr_ch_cnt = dw_edma_v0_core_ch_count(dw, EDMA_DIR_WRITE); - if (!dw->wr_ch_cnt) - return -EINVAL; - } + dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, + dw_edma_v0_core_ch_count(dw, EDMA_DIR_WRITE)); + dw->wr_ch_cnt = min_t(u16, dw->wr_ch_cnt, EDMA_MAX_WR_CH); - if (!dw->rd_ch_cnt) { - /* Find out how many read channels are supported by hardware */ - dw->rd_ch_cnt = dw_edma_v0_core_ch_count(dw, EDMA_DIR_READ); - if (!dw->rd_ch_cnt) - return -EINVAL; - } + dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, + dw_edma_v0_core_ch_count(dw, EDMA_DIR_READ)); + dw->rd_ch_cnt = min_t(u16, dw->rd_ch_cnt, EDMA_MAX_RD_CH); + + if (!dw->wr_ch_cnt && !dw->rd_ch_cnt) + return -EINVAL; dev_vdbg(dev, "Channels:\twrite=%d, read=%d\n", dw->wr_ch_cnt, dw->rd_ch_cnt); diff --git a/drivers/dma/dw-edma/dw-edma-core.h b/drivers/dma/dw-edma/dw-edma-core.h index f72ebaa118af..650b1c7d30b7 100644 --- a/drivers/dma/dw-edma/dw-edma-core.h +++ b/drivers/dma/dw-edma/dw-edma-core.h @@ -15,6 +15,8 @@ #include "../virt-dma.h" #define EDMA_LL_SZ 24 +#define EDMA_MAX_WR_CH 8 +#define EDMA_MAX_RD_CH 8 enum dw_edma_dir { EDMA_DIR_WRITE = 0, -- cgit v1.2.3