[PATCH 6.1 069/473] firmware: raspberrypi: Use correct device for DMA mappings

Greg Kroah-Hartman
2024-06-06T14:13:15Z

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

[ Upstream commit df518a0ae1b982a4dcf2235464016c0c4576a34d ]

The buffer used to transfer data over the mailbox interface is mapped
using the client's device. This is incorrect, as the device performing
the DMA transfer is the mailbox itself. Fix it by using the mailbox
controller device instead.

This requires including the mailbox_controller.h header to dereference
the mbox_chan and mbox_controller structures. The header is not meant to
be included by clients. This could be fixed by extending the client API
with a function to access the controller's device.

Fixes: 4e3d60656a72 ("ARM: bcm2835: Add the Raspberry Pi firmware driver")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Stefan Wahren <wahrenst@gmx.net>
Tested-by: Ivan T. Ivanov <iivanov@suse.de>
Link: https://lore.kernel.org/r/20240326195807.15163-3-laurent.pinchart@ideasonboard.com
Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/firmware/raspberrypi.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c
index dba315f675bc7..ec223976c972d 100644
--- a/drivers/firmware/raspberrypi.c
+++ b/drivers/firmware/raspberrypi.c
@@ -9,6 +9,7 @@
#include <linux/dma-mapping.h>
#include <linux/kref.h>
#include <linux/mailbox_client.h>
+#include <linux/mailbox_controller.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
@@ -96,8 +97,8 @@ int rpi_firmware_property_list(struct rpi_firmware *fw,
if (size & 3)
return -EINVAL;

- buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr,
- GFP_ATOMIC);
+ buf = dma_alloc_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size),
+ &bus_addr, GFP_ATOMIC);
if (!buf)
return -ENOMEM;

@@ -125,7 +126,7 @@ int rpi_firmware_property_list(struct rpi_firmware *fw,
ret = -EINVAL;
}

- dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr);
+ dma_free_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size), buf, bus_addr);

return ret;
}
--
2.43.0