mmc: mmci_sdmmc: fix DMA API warning max segment size

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@st.com>
Link: https://lore.kernel.org/r/20200526155103.12514-3-ludovic.barre@st.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
index 2965b1c062e19ee2538d6a034ff48e47e0a0c5df..51db30acf4dcaf32e08d3e28a8adb3443d2f44a4 100644 (file)
--- 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)