[PATCH 2/2] mmc: mmci_sdmmc: fix DMA API warning max segment size
From: Ludovic Barre
Date: Tue May 26 2020 - 11:51:29 EST
Turning on CONFIG_DMA_API_DEBUG_SG results in the following warning:
WARNING: CPU: 1 PID: 85 at kernel/dma/debug.c:1302 debug_dma_map_sg+0x2a0/0x3cc
mmci-pl18x 58005000.sdmmc: DMA-API: mapping sg segment longer than device claims to support [len=126976] [max=65536]
dma api debug checks and compares the segment size to
dma_get_max_seg_size (dev->dma_parms->max_segment_size),
the sdmmc variant has an internal DMA and should define
its max_segment_size constraint to avoid this warning.
This Patch defines the dev->dma_parms->max_segment_size
with the constraint already set for mmc core
(host->mmc->max_seg_size).
Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
drivers/mmc/host/mmci_stm32_sdmmc.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
index 2965b1c062e1..51db30acf4dc 100644
--- a/drivers/mmc/host/mmci_stm32_sdmmc.c
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -119,20 +119,19 @@ static void sdmmc_idma_unprep_data(struct mmci_host *host,
static int sdmmc_idma_setup(struct mmci_host *host)
{
struct sdmmc_idma *idma;
+ struct device *dev = mmc_dev(host->mmc);
- idma = devm_kzalloc(mmc_dev(host->mmc), sizeof(*idma), GFP_KERNEL);
+ idma = devm_kzalloc(dev, sizeof(*idma), GFP_KERNEL);
if (!idma)
return -ENOMEM;
host->dma_priv = idma;
if (host->variant->dma_lli) {
- idma->sg_cpu = dmam_alloc_coherent(mmc_dev(host->mmc),
- SDMMC_LLI_BUF_LEN,
+ idma->sg_cpu = dmam_alloc_coherent(dev, SDMMC_LLI_BUF_LEN,
&idma->sg_dma, GFP_KERNEL);
if (!idma->sg_cpu) {
- dev_err(mmc_dev(host->mmc),
- "Failed to alloc IDMA descriptor\n");
+ dev_err(dev, "Failed to alloc IDMA descriptor\n");
return -ENOMEM;
}
host->mmc->max_segs = SDMMC_LLI_BUF_LEN /
@@ -143,7 +142,7 @@ static int sdmmc_idma_setup(struct mmci_host *host)
host->mmc->max_seg_size = host->mmc->max_req_size;
}
- return 0;
+ return dma_set_max_seg_size(dev, host->mmc->max_seg_size);
}
static int sdmmc_idma_start(struct mmci_host *host, unsigned int *datactrl)
--
2.17.1