[PATCH] dmaengine: ste_dma40: Preserve the LCPA I/O address space

From: Linus Walleij

Date: Fri Oct 09 2026 - 19:00:40 EST


The LCPA area is mapped with devm_ioremap(), but lcpa_base and the
per-channel lcpa pointer lack __iomem annotations. This loses the I/O
address space and makes sparse warn when d40_current_addr() assigns
LCPA register addresses to its __iomem pointers.

Annotate both pointers and the LCPA argument of d40_log_lli_lcpa_write()
to preserve the I/O address space from the mapping to the register
accessors. This also fixes the existing LCPA read and write warnings
without changing the generated code.

Fixes: c80edceff29e ("dmaengine: ste_dma40: Fix cyclic transfer residue")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202610090216.pjMRxhRL-lkp@xxxxxxxxx/
Assisted-by: LLM
Signed-off-by: Linus Walleij <linusw@xxxxxxxxxx>
---
drivers/dma/ste_dma40.c | 4 ++--
drivers/dma/ste_dma40_ll.c | 8 ++++----
drivers/dma/ste_dma40_ll.h | 2 +-
3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index d3cc2c512ccf..74dd4cbdc3c0 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -509,7 +509,7 @@ struct d40_chan {
u32 src_def_cfg;
u32 dst_def_cfg;
struct d40_def_lcsp log_def;
- struct d40_log_lli_full *lcpa;
+ struct d40_log_lli_full __iomem *lcpa;
/* Runtime reconfiguration */
dma_addr_t runtime_addr;
enum dma_transfer_direction runtime_direction;
@@ -617,7 +617,7 @@ struct d40_base {
/* Physical half channels */
struct d40_phy_res *phy_res;
struct d40_lcla_pool lcla_pool;
- void *lcpa_base;
+ void __iomem *lcpa_base;
dma_addr_t phy_lcpa;
resource_size_t lcpa_size;
struct kmem_cache *desc_slab;
diff --git a/drivers/dma/ste_dma40_ll.c b/drivers/dma/ste_dma40_ll.c
index 4c489b126cb2..3be7f5b1abb0 100644
--- a/drivers/dma/ste_dma40_ll.c
+++ b/drivers/dma/ste_dma40_ll.c
@@ -333,10 +333,10 @@ static void d40_log_lli_link(struct d40_log_lli *lli_dst,
(dlos << D40_MEM_LCSP1_SLOS_POS);
}

-void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
- struct d40_log_lli *lli_dst,
- struct d40_log_lli *lli_src,
- int next, unsigned int flags)
+void d40_log_lli_lcpa_write(struct d40_log_lli_full __iomem *lcpa,
+ struct d40_log_lli *lli_dst,
+ struct d40_log_lli *lli_src,
+ int next, unsigned int flags)
{
d40_log_lli_link(lli_dst, lli_src, next, flags);

diff --git a/drivers/dma/ste_dma40_ll.h b/drivers/dma/ste_dma40_ll.h
index 55090cb31057..ca9d07649361 100644
--- a/drivers/dma/ste_dma40_ll.h
+++ b/drivers/dma/ste_dma40_ll.h
@@ -455,7 +455,7 @@ int d40_log_sg_to_lli(struct scatterlist *sg,
u32 lcsp13, /* src or dst*/
u32 data_width1, u32 data_width2);

-void d40_log_lli_lcpa_write(struct d40_log_lli_full *lcpa,
+void d40_log_lli_lcpa_write(struct d40_log_lli_full __iomem *lcpa,
struct d40_log_lli *lli_dst,
struct d40_log_lli *lli_src,
int next, unsigned int flags);

---
base-commit: 511afae96d89847f753fcab6b3a597f0281be9d5
change-id: 20261010-dma40-smatch-fix-42fce06d4f25

Best regards,
--
Linus Walleij <linusw@xxxxxxxxxx>