FAILED: patch "[PATCH] wifi: brcmfmac: set F2 blocksize to 256 for BCM43752" failed to apply to 6.1-stable tree

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 29ab31f3f27157648f2f7e6d5e1fd9792fdf0614
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026072950-scribing-blooming-1fda@gregkh' --subject-prefix 'PATCH 6.1.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 29ab31f3f27157648f2f7e6d5e1fd9792fdf0614 Mon Sep 17 00:00:00 2001
From: LiangCheng Wang <[email protected]>
Date: Wed, 15 Jul 2026 14:49:38 +0800
Subject: [PATCH] wifi: brcmfmac: set F2 blocksize to 256 for BCM43752

The BCM43752 is not reliable with the default 512-byte SDIO function 2 block size: on an i.MX8MP board with an AMPAK AP6275S module at SDR104 / 200 MHz, an iperf TX stress test kills WLAN within seconds:

mmc_submit_one: CMD53 sg block write failed -84
brcmf_sdio_dpc: failed backplane access over SDIO, halting operation

Commit d2587c57ffd8 ("brcmfmac: add 43752 SDIO ids and initialization") set up the 43752 like the 4373 for the F2 watermark but missed the F2 block size, which the 4373 limits to 256 bytes. The vendor driver (bcmdhd) also programs a 256-byte F2 block size for this chip and runs the same hardware without errors.

Group the 43752 with the 4373, matching the F2 watermark handling. With this change a 10-minute bidirectional iperf3 soak completes with zero SDIO errors at ~270 Mbit/s in each direction.

Backporting note: kernels before v6.18 name this id SDIO_DEVICE_ID_BROADCOM_CYPRESS_43752, so on those trees the case label added by this patch must be adjusted to that name. Cherry-picking the rename commit 74e2ef72bd4b ("wifi: brcmfmac: fix 43752 SDIO FWVID incorrectly labelled as Cypress (CYW)") first is not a clean
alternative: on trees before v6.17 its context collides with the 43751 additions, and trees before v6.2 lack the FWVID framework it touches.

index ec487c6f2e38..869c4872d399 100644
@@ -911,6 +911,7 @@ int brcmf_sdiod_probe(struct brcmf_sdio_dev *sdiodev)
 		return ret;
 	}
 	switch (sdiodev->func2->device) {
+	case SDIO_DEVICE_ID_BROADCOM_43752:
 	case SDIO_DEVICE_ID_BROADCOM_CYPRESS_4373:
 		f2_blksz = SDIO_4373_FUNC2_BLOCKSIZE;
 		break;

From: Gokul Sivakumar <[email protected]>

[ Upstream commit 74e2ef72bd4b25ce21c8f309d4f5b91b5df9ff5b ]

Cypress(Infineon) is not the vendor for this 43752 SDIO WLAN chip, and so has not officially released any firmware binary for it. It is incorrect to maintain this WLAN chip with firmware vendor ID as "CYW". So relabel the chip's firmware Vendor ID as "WCC" as suggested by the maintainer.

Stable-dep-of: 29ab31f3f271 ("wifi: brcmfmac: set F2 blocksize to 256 for BCM43752")

---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 2 +-
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c   | 2 +-
 include/linux/mmc/sdio_ids.h                              | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

index 7cd8ec6f515a4..252160f7ffd2b 100644
@@ -981,10 +981,10 @@ static const struct sdio_device_id brcmf_sdmmc_ids[] = {
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_4354),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_4356),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_4359),
+	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_43752),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_CYPRESS_4373),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_CYPRESS_43012),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_CYPRESS_43439),
-	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_CYPRESS_43752),
 	BRCMF_SDIO_DEVICE(SDIO_DEVICE_ID_BROADCOM_CYPRESS_89359),
 	{ /* end: all zeroes */ }
 };

index 5f6c0afe22d49..caac171175a67 100644
@@ -4267,8 +4267,8 @@ static void brcmf_sdio_firmware_callback(struct device *dev, int err,
 				   bus->hostintmask, NULL);
 
 		switch (sdiod->func1->device) {
+		case SDIO_DEVICE_ID_BROADCOM_43752:
 		case SDIO_DEVICE_ID_BROADCOM_CYPRESS_4373:
-		case SDIO_DEVICE_ID_BROADCOM_CYPRESS_43752:
 			brcmf_dbg(INFO, "set F2 watermark to 0x%x*4 bytes\n",
 				  CY_4373_F2_WATERMARK);
 			brcmf_sdiod_writeb(sdiod, SBSDIO_WATERMARK,

index 0e4ef9c5127ad..3628f89f04894 100644
@@ -76,7 +76,7 @@
 #define SDIO_DEVICE_ID_BROADCOM_43430		0xa9a6
 #define SDIO_DEVICE_ID_BROADCOM_CYPRESS_43439	0xa9af
 #define SDIO_DEVICE_ID_BROADCOM_43455		0xa9bf
-#define SDIO_DEVICE_ID_BROADCOM_CYPRESS_43752	0xaae8
+#define SDIO_DEVICE_ID_BROADCOM_43752		0xaae8
 
 #define SDIO_VENDOR_ID_MARVELL			0x02df
 #define SDIO_DEVICE_ID_MARVELL_LIBERTAS		0x9103

2.53.0

From: LiangCheng Wang <[email protected]>

[ Upstream commit 29ab31f3f27157648f2f7e6d5e1fd9792fdf0614 ]

The BCM43752 is not reliable with the default 512-byte SDIO function 2 block size: on an i.MX8MP board with an AMPAK AP6275S module at SDR104 / 200 MHz, an iperf TX stress test kills WLAN within seconds:

mmc_submit_one: CMD53 sg block write failed -84
brcmf_sdio_dpc: failed backplane access over SDIO, halting operation

Commit d2587c57ffd8 ("brcmfmac: add 43752 SDIO ids and initialization") set up the 43752 like the 4373 for the F2 watermark but missed the F2 block size, which the 4373 limits to 256 bytes. The vendor driver (bcmdhd) also programs a 256-byte F2 block size for this chip and runs the same hardware without errors.

Group the 43752 with the 4373, matching the F2 watermark handling. With this change a 10-minute bidirectional iperf3 soak completes with zero SDIO errors at ~270 Mbit/s in each direction.

Backporting note: kernels before v6.18 name this id SDIO_DEVICE_ID_BROADCOM_CYPRESS_43752, so on those trees the case label added by this patch must be adjusted to that name. Cherry-picking the rename commit 74e2ef72bd4b ("wifi: brcmfmac: fix 43752 SDIO FWVID incorrectly labelled as Cypress (CYW)") first is not a clean
alternative: on trees before v6.17 its context collides with the 43751 additions, and trees before v6.2 lack the FWVID framework it touches.

---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/bcmsdh.c | 1 +
 1 file changed, 1 insertion(+)

index 252160f7ffd2b..207be0b9001a0 100644
@@ -906,6 +906,7 @@ int brcmf_sdiod_probe(struct brcmf_sdio_dev *sdiodev)
 		return ret;
 	}
 	switch (sdiodev->func2->device) {
+	case SDIO_DEVICE_ID_BROADCOM_43752:
 	case SDIO_DEVICE_ID_BROADCOM_CYPRESS_4373:
 		f2_blksz = SDIO_4373_FUNC2_BLOCKSIZE;
 		break;

2.53.0