[PATCH v2 1/1] mmc: use dmaengine_get_dma_device() instead of chan->device->dev

From: Frank . Li

Date: Fri Sep 18 2026 - 11:36:38 EST


From: Frank Li <Frank.Li@xxxxxxx>

Replace direct dma_chan::device::dev access with the proper
dmaengine_get_dma_device() for consumer API

chan->device->dev is not always the device used for DMA mapping.
Some DMA engines support per-channel IOMMU mappings, so different
channels may use different DMA devices. dmaengine_get_dma_device()
returns the correct device for each channel.

This also prepares for making the DMA engine provider data structures
private. DMA consumers should not access DMA engine internals directly.

Assisted-by: LLM
Reviewed-by: Linus Walleij <linusw@xxxxxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
Change in v2
- find more place, which use device->dev for dma mapping. This time should
clean all.
- Reviewed-by: Linus Walleij <linusw@xxxxxxxxxx>

Cc: imx@xxxxxxxxxxxxxxx
Cc: vkoul@xxxxxxxxxx
---
drivers/mmc/host/atmel-mci.c | 8 +++++---
drivers/mmc/host/jz4740_mmc.c | 8 ++++----
drivers/mmc/host/mmci.c | 14 +++++++-------
drivers/mmc/host/moxart-mmc.c | 10 ++++++----
drivers/mmc/host/mxcmmc.c | 12 +++++-------
drivers/mmc/host/omap_hsmmc.c | 12 ++++++------
drivers/mmc/host/owl-mmc.c | 4 ++--
drivers/mmc/host/pxamci.c | 4 ++--
drivers/mmc/host/renesas_sdhi_sys_dmac.c | 8 ++++----
drivers/mmc/host/sh_mmcif.c | 8 ++++----
drivers/mmc/host/usdhi6rol0.c | 6 +++---
11 files changed, 48 insertions(+), 46 deletions(-)

diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c
index 8f4df250a77a0..fb756e8858db3 100644
--- a/drivers/mmc/host/atmel-mci.c
+++ b/drivers/mmc/host/atmel-mci.c
@@ -961,7 +961,7 @@ static void atmci_dma_cleanup(struct atmel_mci *host)
struct mmc_data *data = host->data;

if (data)
- dma_unmap_sg(host->dma.chan->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(host->dma.chan),
data->sg, data->sg_len,
mmc_get_dma_dir(data));
}
@@ -1116,6 +1116,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
unsigned int sglen;
u32 maxburst;
u32 iflags;
+ struct device *dma_dev;

data->error = -EINPROGRESS;

@@ -1145,6 +1146,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
return -ENODEV;

chan = host->dma.chan;
+ dma_dev = dmaengine_get_dma_device(chan);
host->data_chan = chan;

if (data->flags & MMC_DATA_READ) {
@@ -1161,7 +1163,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)
atmci_writel(host, ATMCI_DMA, ATMCI_DMA_CHKSIZE(maxburst) |
ATMCI_DMAEN);

- sglen = dma_map_sg(chan->device->dev, data->sg,
+ sglen = dma_map_sg(dma_dev, data->sg,
data->sg_len, mmc_get_dma_dir(data));

dmaengine_slave_config(chan, &host->dma_conf);
@@ -1177,7 +1179,7 @@ atmci_prepare_data_dma(struct atmel_mci *host, struct mmc_data *data)

return iflags;
unmap_exit:
- dma_unmap_sg(chan->device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dma_dev, data->sg, data->sg_len,
mmc_get_dma_dir(data));
return -ENOMEM;
}
diff --git a/drivers/mmc/host/jz4740_mmc.c b/drivers/mmc/host/jz4740_mmc.c
index 6a3c26b7c82d8..3343c8aa1bffe 100644
--- a/drivers/mmc/host/jz4740_mmc.c
+++ b/drivers/mmc/host/jz4740_mmc.c
@@ -256,7 +256,7 @@ static int jz4740_mmc_acquire_dma_channels(struct jz4740_mmc_host *host)
* the parameters of the DMA engine device.
*/
if (host->dma_tx) {
- struct device *dev = host->dma_tx->device->dev;
+ struct device *dev = dmaengine_get_dma_device(host->dma_tx);
unsigned int max_seg_size = dma_get_max_seg_size(dev);

if (max_seg_size < host->mmc->max_seg_size)
@@ -264,7 +264,7 @@ static int jz4740_mmc_acquire_dma_channels(struct jz4740_mmc_host *host)
}

if (host->dma_rx) {
- struct device *dev = host->dma_rx->device->dev;
+ struct device *dev = dmaengine_get_dma_device(host->dma_rx);
unsigned int max_seg_size = dma_get_max_seg_size(dev);

if (max_seg_size < host->mmc->max_seg_size)
@@ -289,7 +289,7 @@ static void jz4740_mmc_dma_unmap(struct jz4740_mmc_host *host,
struct dma_chan *chan = jz4740_mmc_get_dma_chan(host, data);
enum dma_data_direction dir = mmc_get_dma_dir(data);

- dma_unmap_sg(chan->device->dev, data->sg, data->sg_len, dir);
+ dma_unmap_sg(dmaengine_get_dma_device(chan), data->sg, data->sg_len, dir);
data->host_cookie = COOKIE_UNMAPPED;
}

@@ -307,7 +307,7 @@ static int jz4740_mmc_prepare_dma_data(struct jz4740_mmc_host *host,
if (data->host_cookie == COOKIE_PREMAPPED)
return data->sg_count;

- sg_count = dma_map_sg(chan->device->dev,
+ sg_count = dma_map_sg(dmaengine_get_dma_device(chan),
data->sg,
data->sg_len,
dir);
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 416bdb184ed4c..2d72f56d354f1 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -893,14 +893,14 @@ int mmci_dmae_setup(struct mmci_host *host)
* the parameters of the DMA engine device.
*/
if (dmae->tx_channel) {
- struct device *dev = dmae->tx_channel->device->dev;
+ struct device *dev = dmaengine_get_dma_device(dmae->tx_channel);
unsigned int max_seg_size = dma_get_max_seg_size(dev);

if (max_seg_size < host->mmc->max_seg_size)
host->mmc->max_seg_size = max_seg_size;
}
if (dmae->rx_channel) {
- struct device *dev = dmae->rx_channel->device->dev;
+ struct device *dev = dmaengine_get_dma_device(dmae->rx_channel);
unsigned int max_seg_size = dma_get_max_seg_size(dev);

if (max_seg_size < host->mmc->max_seg_size)
@@ -940,7 +940,7 @@ static void mmci_dma_unmap(struct mmci_host *host, struct mmc_data *data)
else
chan = dmae->tx_channel;

- dma_unmap_sg(chan->device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dmaengine_get_dma_device(chan), data->sg, data->sg_len,
mmc_get_dma_dir(data));
}

@@ -1023,7 +1023,7 @@ static int _mmci_dmae_prep_data(struct mmci_host *host, struct mmc_data *data,
.device_fc = variant->dma_flow_controller,
};
struct dma_chan *chan;
- struct dma_device *device;
+ struct device *dma_dev;
struct dma_async_tx_descriptor *desc;
int nr_sg;
unsigned long flags = DMA_CTRL_ACK;
@@ -1056,8 +1056,8 @@ static int _mmci_dmae_prep_data(struct mmci_host *host, struct mmc_data *data,
if (host->variant->dma_power_of_2 && !is_power_of_2(data->blksz))
return -EINVAL;

- device = chan->device;
- nr_sg = dma_map_sg(device->dev, data->sg, data->sg_len,
+ dma_dev = dmaengine_get_dma_device(chan);
+ nr_sg = dma_map_sg(dma_dev, data->sg, data->sg_len,
mmc_get_dma_dir(data));
if (nr_sg == 0)
return -EINVAL;
@@ -1077,7 +1077,7 @@ static int _mmci_dmae_prep_data(struct mmci_host *host, struct mmc_data *data,
return 0;

unmap_exit:
- dma_unmap_sg(device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dma_dev, data->sg, data->sg_len,
mmc_get_dma_dir(data));
return -ENOMEM;
}
diff --git a/drivers/mmc/host/moxart-mmc.c b/drivers/mmc/host/moxart-mmc.c
index 28aed13549a64..6c0974c494207 100644
--- a/drivers/mmc/host/moxart-mmc.c
+++ b/drivers/mmc/host/moxart-mmc.c
@@ -262,6 +262,7 @@ static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
u32 len, dir_slave;
struct dma_async_tx_descriptor *desc = NULL;
struct dma_chan *dma_chan;
+ struct device *dma_dev;
long timeout;

if (host->data_len == data->bytes_xfered)
@@ -275,7 +276,8 @@ static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
dir_slave = DMA_DEV_TO_MEM;
}

- len = dma_map_sg(dma_chan->device->dev, data->sg,
+ dma_dev = dmaengine_get_dma_device(dma_chan);
+ len = dma_map_sg(dma_dev, data->sg,
data->sg_len, mmc_get_dma_dir(data));

if (len > 0) {
@@ -306,7 +308,7 @@ static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
data->bytes_xfered = host->data_len;

unmap:
- dma_unmap_sg(dma_chan->device->dev,
+ dma_unmap_sg(dma_dev,
data->sg, data->sg_len,
mmc_get_dma_dir(data));
}
@@ -642,8 +644,8 @@ static int moxart_probe(struct platform_device *pdev)
dmaengine_slave_config(host->dma_chan_rx, &cfg);

mmc->max_seg_size = min3(mmc->max_req_size,
- dma_get_max_seg_size(host->dma_chan_rx->device->dev),
- dma_get_max_seg_size(host->dma_chan_tx->device->dev));
+ dma_get_max_seg_size(dmaengine_get_dma_device(host->dma_chan_rx)),
+ dma_get_max_seg_size(dmaengine_get_dma_device(host->dma_chan_tx)));
}

if (readl(host->base + REG_BUS_WIDTH) & BUS_WIDTH_4_SUPPORT)
diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
index 097498a3f8ff4..c20cff770395e 100644
--- a/drivers/mmc/host/mxcmmc.c
+++ b/drivers/mmc/host/mxcmmc.c
@@ -290,6 +290,7 @@ static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
unsigned int datasize = nob * blksz;
struct scatterlist *sg;
enum dma_transfer_direction slave_dirn;
+ struct device *dma_dev = dmaengine_get_dma_device(host->dma);
int i, nents;

host->data = data;
@@ -319,8 +320,7 @@ static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
mxcmci_swap_buffers(data);
}

- nents = dma_map_sg(host->dma->device->dev, data->sg,
- data->sg_len, host->dma_dir);
+ nents = dma_map_sg(dma_dev, data->sg, data->sg_len, host->dma_dir);
if (nents != data->sg_len)
return -EINVAL;

@@ -329,8 +329,7 @@ static int mxcmci_setup_data(struct mxcmci_host *host, struct mmc_data *data)
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);

if (!host->desc) {
- dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
- host->dma_dir);
+ dma_unmap_sg(dma_dev, data->sg, data->sg_len, host->dma_dir);
host->do_dma = 0;
return 0; /* Fall back to PIO */
}
@@ -439,7 +438,7 @@ static int mxcmci_finish_data(struct mxcmci_host *host, unsigned int stat)
int data_error;

if (mxcmci_use_dma(host)) {
- dma_unmap_sg(host->dma->device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dmaengine_get_dma_device(host->dma), data->sg, data->sg_len,
host->dma_dir);
mxcmci_swap_buffers(data);
}
@@ -1125,8 +1124,7 @@ static int mxcmci_probe(struct platform_device *pdev)
}
}
if (host->dma)
- mmc->max_seg_size = dma_get_max_seg_size(
- host->dma->device->dev);
+ mmc->max_seg_size = dma_get_max_seg_size(dmaengine_get_dma_device(host->dma));
else
dev_info(mmc_dev(host->mmc), "dma not available. Using PIO\n");

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index de5a3b70107d8..44c326fd2a9b2 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -915,7 +915,7 @@ static void omap_hsmmc_dma_cleanup(struct omap_hsmmc_host *host, int errno)
struct dma_chan *chan = omap_hsmmc_get_dma_chan(host, host->data);

dmaengine_terminate_all(chan);
- dma_unmap_sg(chan->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(chan),
host->data->sg, host->data->sg_len,
mmc_get_dma_dir(host->data));

@@ -1170,7 +1170,7 @@ static void omap_hsmmc_dma_callback(void *param)
data = host->mrq->data;
chan = omap_hsmmc_get_dma_chan(host, data);
if (!data->host_cookie)
- dma_unmap_sg(chan->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(chan),
data->sg, data->sg_len,
mmc_get_dma_dir(data));

@@ -1204,7 +1204,7 @@ static int omap_hsmmc_pre_dma_transfer(struct omap_hsmmc_host *host,

/* Check if next job is already prepared */
if (next || data->host_cookie != host->next_data.cookie) {
- dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
+ dma_len = dma_map_sg(dmaengine_get_dma_device(chan), data->sg, data->sg_len,
mmc_get_dma_dir(data));

} else {
@@ -1390,7 +1390,7 @@ static void omap_hsmmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
if (host->use_dma && data->host_cookie) {
struct dma_chan *c = omap_hsmmc_get_dma_chan(host, data);

- dma_unmap_sg(c->device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dmaengine_get_dma_device(c), data->sg, data->sg_len,
mmc_get_dma_dir(data));
data->host_cookie = 0;
}
@@ -1912,8 +1912,8 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
* increase this figure here, we get warnings from the DMA API debug.
*/
mmc->max_seg_size = min3(mmc->max_req_size,
- dma_get_max_seg_size(host->rx_chan->device->dev),
- dma_get_max_seg_size(host->tx_chan->device->dev));
+ dma_get_max_seg_size(dmaengine_get_dma_device(host->rx_chan)),
+ dma_get_max_seg_size(dmaengine_get_dma_device(host->tx_chan)));

/* Request IRQ for MMC operations */
ret = devm_request_irq(&pdev->dev, host->irq, omap_hsmmc_irq, 0,
diff --git a/drivers/mmc/host/owl-mmc.c b/drivers/mmc/host/owl-mmc.c
index d5b8a110267b8..668cf9704ac29 100644
--- a/drivers/mmc/host/owl-mmc.c
+++ b/drivers/mmc/host/owl-mmc.c
@@ -162,7 +162,7 @@ static void owl_mmc_finish_request(struct owl_mmc_host *owl_host)
owl_host->mrq = NULL;

if (data)
- dma_unmap_sg(owl_host->dma->device->dev, data->sg, data->sg_len,
+ dma_unmap_sg(dmaengine_get_dma_device(owl_host->dma), data->sg, data->sg_len,
owl_host->dma_dir);

/* Finally finish request */
@@ -313,7 +313,7 @@ static int owl_mmc_prepare_data(struct owl_mmc_host *owl_host,
owl_host->dma_cfg.direction = DMA_DEV_TO_MEM;
}

- dma_map_sg(owl_host->dma->device->dev, data->sg,
+ dma_map_sg(dmaengine_get_dma_device(owl_host->dma), data->sg,
data->sg_len, owl_host->dma_dir);

dmaengine_slave_config(owl_host->dma, &owl_host->dma_cfg);
diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index f8427f071c009..c3edd98376bcc 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -201,7 +201,7 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data)
return;
}

- host->dma_len = dma_map_sg(chan->device->dev, data->sg, data->sg_len,
+ host->dma_len = dma_map_sg(dmaengine_get_dma_device(chan), data->sg, data->sg_len,
host->dma_dir);

tx = dmaengine_prep_slave_sg(chan, data->sg, host->dma_len, direction,
@@ -337,7 +337,7 @@ static int pxamci_data_done(struct pxamci_host *host, unsigned int stat)
chan = host->dma_chan_rx;
else
chan = host->dma_chan_tx;
- dma_unmap_sg(chan->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(chan),
data->sg, data->sg_len, host->dma_dir);

if (stat & STAT_READ_TIME_OUT)
diff --git a/drivers/mmc/host/renesas_sdhi_sys_dmac.c b/drivers/mmc/host/renesas_sdhi_sys_dmac.c
index c7df4da9e865b..bf2b32cfbec6c 100644
--- a/drivers/mmc/host/renesas_sdhi_sys_dmac.c
+++ b/drivers/mmc/host/renesas_sdhi_sys_dmac.c
@@ -134,11 +134,11 @@ static void renesas_sdhi_sys_dmac_dma_callback(void *arg)
goto out;

if (host->data->flags & MMC_DATA_READ)
- dma_unmap_sg(host->chan_rx->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_rx),
host->sg_ptr, host->sg_len,
DMA_FROM_DEVICE);
else
- dma_unmap_sg(host->chan_tx->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_tx),
host->sg_ptr, host->sg_len,
DMA_TO_DEVICE);

@@ -188,7 +188,7 @@ static void renesas_sdhi_sys_dmac_start_dma_rx(struct tmio_mmc_host *host)
sg = host->sg_ptr;
}

- ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_FROM_DEVICE);
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sg, host->sg_len, DMA_FROM_DEVICE);
if (ret > 0)
desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_DEV_TO_MEM,
DMA_CTRL_ACK);
@@ -264,7 +264,7 @@ static void renesas_sdhi_sys_dmac_start_dma_tx(struct tmio_mmc_host *host)
sg = host->sg_ptr;
}

- ret = dma_map_sg(chan->device->dev, sg, host->sg_len, DMA_TO_DEVICE);
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sg, host->sg_len, DMA_TO_DEVICE);
if (ret > 0)
desc = dmaengine_prep_slave_sg(chan, sg, ret, DMA_MEM_TO_DEV,
DMA_CTRL_ACK);
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c
index a205c222a821d..e8d2bd1491eee 100644
--- a/drivers/mmc/host/sh_mmcif.c
+++ b/drivers/mmc/host/sh_mmcif.c
@@ -289,7 +289,7 @@ static void sh_mmcif_start_dma_rx(struct sh_mmcif_host *host)
dma_cookie_t cookie = -EINVAL;
int ret;

- ret = dma_map_sg(chan->device->dev, sg, data->sg_len,
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sg, data->sg_len,
DMA_FROM_DEVICE);
if (ret > 0) {
host->dma_active = true;
@@ -339,7 +339,7 @@ static void sh_mmcif_start_dma_tx(struct sh_mmcif_host *host)
dma_cookie_t cookie = -EINVAL;
int ret;

- ret = dma_map_sg(chan->device->dev, sg, data->sg_len,
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sg, data->sg_len,
DMA_TO_DEVICE);
if (ret > 0) {
host->dma_active = true;
@@ -1173,11 +1173,11 @@ static bool sh_mmcif_end_cmd(struct sh_mmcif_host *host)
host->timeout);

if (data->flags & MMC_DATA_READ)
- dma_unmap_sg(host->chan_rx->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_rx),
data->sg, data->sg_len,
DMA_FROM_DEVICE);
else
- dma_unmap_sg(host->chan_tx->device->dev,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_tx),
data->sg, data->sg_len,
DMA_TO_DEVICE);

diff --git a/drivers/mmc/host/usdhi6rol0.c b/drivers/mmc/host/usdhi6rol0.c
index 8d9d4f362999f..74888260e85c5 100644
--- a/drivers/mmc/host/usdhi6rol0.c
+++ b/drivers/mmc/host/usdhi6rol0.c
@@ -539,10 +539,10 @@ static void usdhi6_dma_stop_unmap(struct usdhi6_host *host)
host->dma_active = false;

if (data->flags & MMC_DATA_READ)
- dma_unmap_sg(host->chan_rx->device->dev, data->sg,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_rx), data->sg,
data->sg_len, DMA_FROM_DEVICE);
else
- dma_unmap_sg(host->chan_tx->device->dev, data->sg,
+ dma_unmap_sg(dmaengine_get_dma_device(host->chan_tx), data->sg,
data->sg_len, DMA_TO_DEVICE);
}

@@ -583,7 +583,7 @@ static int usdhi6_dma_setup(struct usdhi6_host *host, struct dma_chan *chan,
return -EINVAL;
}

- ret = dma_map_sg(chan->device->dev, sg, data->sg_len, data_dir);
+ ret = dma_map_sg(dmaengine_get_dma_device(chan), sg, data->sg_len, data_dir);
if (ret > 0) {
host->dma_active = true;
desc = dmaengine_prep_slave_sg(chan, sg, ret, dir,
--
2.43.0