On Sun, 23 Aug 2026, David Heidelberg via B4 Relay wrote: > From: David Heidelberg <[email protected]> > > 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: [email protected] > Fixes: f959dcd6ddfd ("dma-direct: Fix potential NULL pointer dereference") > Assisted-by: tencent:hy3 > Signed-off-by: David Heidelberg <[email protected]> > --- > 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); > + } > +
Any reason not to use dma_coerce_mask_and_coherent()? > 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 <[email protected]> > > -- Lee Jones

