[PATCH 6.1 211/325] wifi: rtl8xxxu: retry firmware download on error

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

6.1-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Soeren Moch <smoch@web.de>

[ Upstream commit 3d3e28feca7ac8c6cf2a390dbbe1f97e3feb7f36 ]

Occasionally there is an EPROTO error during firmware download.
This error is converted to EAGAIN in the download function.
But nobody tries again and so device probe fails.

Implement download retry to fix this.

This error was observed (and fix tested) on a tbs2910 board [1]
with an embedded RTL8188EU (0bda:8179) device behind a USB hub.

[1] arch/arm/boot/dts/nxp/imx/imx6q-tbs2910.dts

Signed-off-by: Soeren Moch <smoch@web.de>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20250127194828.599379-1-smoch@web.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 .../wireless/realtek/rtl8xxxu/rtl8xxxu_core.c   | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index 9ccf8550a0679..cd22c756acc69 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -798,9 +798,10 @@ rtl8xxxu_writeN(struct rtl8xxxu_priv *priv, u16 addr, u8 *buf, u16 len)
 	return len;
 
 write_error:
-	dev_info(&udev->dev,
-		 "%s: Failed to write block at addr: %04x size: %04x\n",
-		 __func__, addr, blocksize);
+	if (rtl8xxxu_debug & RTL8XXXU_DEBUG_REG_WRITE)
+		dev_info(&udev->dev,
+			 "%s: Failed to write block at addr: %04x size: %04x\n",
+			 __func__, addr, blocksize);
 	return -EAGAIN;
 }
 
@@ -3920,8 +3921,14 @@ static int rtl8xxxu_init_device(struct ieee80211_hw *hw)
 	 */
 	rtl8xxxu_write16(priv, REG_TRXFF_BNDY + 2, fops->trxff_boundary);
 
-	ret = rtl8xxxu_download_firmware(priv);
-	dev_dbg(dev, "%s: download_firmware %i\n", __func__, ret);
+	for (int retry = 5; retry >= 0 ; retry--) {
+		ret = rtl8xxxu_download_firmware(priv);
+		dev_dbg(dev, "%s: download_firmware %i\n", __func__, ret);
+		if (ret != -EAGAIN)
+			break;
+		if (retry)
+			dev_dbg(dev, "%s: retry firmware download\n", __func__);
+	}
 	if (ret)
 		goto exit;
 	ret = rtl8xxxu_start_firmware(priv);
-- 
2.39.5