[PATCH] mfd: wcd934x: set DMA mask on parent to silence "DMA mask not set"
From: David Heidelberg via B4 Relay
Date: Sun Aug 23 2026 - 06:20:06 EST
From: David Heidelberg <david@xxxxxxx>
The wcd934x MFD parent (a slim_device) never initializes its
dma_mask/coherent_dma_mask. When the DT-aware children pass through
of_dma_configure() this triggers the "DMA mask not set" warning for
each child.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: f959dcd6ddfd ("dma-direct: Fix potential NULL pointer dereference")
Assisted-by: tencent:hy3
Signed-off-by: David Heidelberg <david@xxxxxxx>
---
drivers/mfd/wcd934x.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/mfd/wcd934x.c b/drivers/mfd/wcd934x.c
index 3c3080e8c8cf7..70ee13791d52b 100644
--- a/drivers/mfd/wcd934x.c
+++ b/drivers/mfd/wcd934x.c
@@ -1,12 +1,13 @@
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2019, Linaro Limited
#include <linux/clk.h>
+#include <linux/dma-mapping.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/core.h>
#include <linux/mfd/wcd934x/registers.h>
#include <linux/mfd/wcd934x/wcd934x.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -212,16 +213,21 @@ static int wcd934x_slim_status(struct slim_device *sdev,
static int wcd934x_slim_probe(struct slim_device *sdev)
{
struct device *dev = &sdev->dev;
struct device_node *np = dev->of_node;
struct wcd934x_ddata *ddata;
struct gpio_desc *reset_gpio;
int ret;
+ if (!dev->dma_mask) {
+ dev->dma_mask = &dev->coherent_dma_mask;
+ dev->coherent_dma_mask = DMA_BIT_MASK(32);
+ }
+
ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
if (!ddata)
return -ENOMEM;
ddata->irq = of_irq_get(np, 0);
if (ddata->irq < 0)
return dev_err_probe(ddata->dev, ddata->irq,
"Failed to get IRQ\n");
---
base-commit: 7079a12d7506b07fb53b54a664bfad5fa9b16d70
change-id: 20260823-wcd-dma-bd621ee39887
Best regards,
--
David Heidelberg <david@xxxxxxx>