[PATCH 2/3] mmc: mmci: stm32: manage st,disable-dma-lli property

Yann Gautier
2022-03-04T13:54:06Z

This property is used to disable DMA LLI for an SDMMC instance. We cannot
directly modify the variant struct as it will affect all MMC instances.
The parameter is then copied in the struct sdmmc_idma, and force to 0
if the st,disable-dma-lli property is set in DT.

Signed-off-by: Yann Gautier <yann.gautier@foss.st.com>
---
drivers/mmc/host/mmci_stm32_sdmmc.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
index 9c13f2c31365..02cb0929c465 100644
--- a/drivers/mmc/host/mmci_stm32_sdmmc.c
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -43,6 +43,7 @@ struct sdmmc_lli_desc {
struct sdmmc_idma {
dma_addr_t sg_dma;
void *sg_cpu;
+ u8 dma_lli:1;
};

struct sdmmc_dlyb {
@@ -118,6 +119,7 @@ static void sdmmc_idma_unprep_data(struct mmci_host *host,

static int sdmmc_idma_setup(struct mmci_host *host)
{
+ struct device_node *np = host->mmc->parent->of_node;
struct sdmmc_idma *idma;
struct device *dev = mmc_dev(host->mmc);

@@ -125,9 +127,13 @@ static int sdmmc_idma_setup(struct mmci_host *host)
if (!idma)
return -ENOMEM;

+ idma->dma_lli = host->variant->dma_lli;
+ if (of_get_property(np, "st,disable-dma-lli", NULL))
+ idma->dma_lli = 0;
+
host->dma_priv = idma;

- if (host->variant->dma_lli) {
+ if (idma->dma_lli) {
idma->sg_cpu = dmam_alloc_coherent(dev, SDMMC_LLI_BUF_LEN,
&idma->sg_dma, GFP_KERNEL);
if (!idma->sg_cpu) {
@@ -154,7 +160,7 @@ static int sdmmc_idma_start(struct mmci_host *host, unsigned int *datactrl)
struct scatterlist *sg;
int i;

- if (!host->variant->dma_lli || data->sg_len == 1) {
+ if (!idma->dma_lli || data->sg_len == 1) {
writel_relaxed(sg_dma_address(data->sg),
host->base + MMCI_STM32_IDMABASE0R);
writel_relaxed(MMCI_STM32_IDMAEN,
--
2.25.1