[PATCH 1/5] dmaengine: edma: Implement protection for invalid max_burst
Peter Ujfalusi
peter.ujfalusi at ti.com
Tue Sep 12 03:44:20 PDT 2017
Set the device's max_burst to 32767 (CIDX is 16bit signed value) so clients
can take this into consideration when setting up the trasnfer.
During slave transfer preparation check if the requested maxburst is valid.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
---
drivers/dma/edma.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index 3879f80a4815..6970355abdc9 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -891,6 +891,10 @@ static int edma_slave_config(struct dma_chan *chan,
cfg->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
return -EINVAL;
+ if (cfg->src_maxburst > chan->device->max_burst ||
+ cfg->dst_maxburst > chan->device->max_burst)
+ return -EINVAL;
+
memcpy(&echan->cfg, cfg, sizeof(echan->cfg));
return 0;
@@ -1855,6 +1859,7 @@ static void edma_dma_init(struct edma_cc *ecc, bool legacy_mode)
s_ddev->dst_addr_widths = EDMA_DMA_BUSWIDTHS;
s_ddev->directions |= (BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV));
s_ddev->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+ s_ddev->max_burst = SZ_32K - 1; /* CIDX: 16bit signed */
s_ddev->dev = ecc->dev;
INIT_LIST_HEAD(&s_ddev->channels);
--
2.14.1
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