bes2600: gate device LP-mode entry on successful per-VIF firmware handshake

bes2600_pwr_enter_lp_mode() drives the transition to low-power for each
associated STA VIF: it pushes wsm_set_pm(), waits up to 5 seconds on
pm_enter_cmpl for the firmware to acknowledge, then unconditionally
calls bes2600_pwr_device_enter_lp_mode() to drop the device end of the
bus.

Two bugs:

1. A failed wsm_set_pm() only logs an error, then still falls into
   wait_for_completion_timeout() on a completion the firmware will
   never post (the set-mode command never reached it). The loop
   therefore always blocks the full 5 s, logs a second error, and
   proceeds.

2. A genuine wait-timeout (firmware received the set-mode command but
   never posted the indication) also only logs a warning. The code
   then drops to bes2600_pwr_device_enter_lp_mode(), handing the
   device subsystem an inconsistent view of mac-layer state.

On PineTab2 (BES2600WM + RK3566) the second bug is the recurring
root-cause of the 'bes2600_pwr_enter_lp_mode, wait pm ind timeout'
message flooding dmesg every 5-10 s when the interface is associated
and idle. Sending the device to LP in that state cascades into the
SDIO TX path as the 'bes_sdio_memcpy_to_io_helper / sdio_tx_work'
WARN splat.

Fix:
  - Add a 'timeouts' counter; bump it on both failure paths.
  - Skip the wait_for_completion entirely when wsm_set_pm() failed
    (there is no completion to wait for).
  - Only call bes2600_pwr_device_enter_lp_mode() when every per-VIF
    handshake reached firmware-ACKed completion; otherwise return
    -ETIMEDOUT and leave the device in its current power state.

Tested-on: PineTab2 running linux-pinetab2 6.19.10-danctnix1-1.
Post-patch the handshake still fails on this particular firmware
revision (separate root-cause investigation outside this patch), but
the driver now returns -ETIMEDOUT cleanly instead of flooding dmesg
and destabilising the SDIO path.

Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>

bes2600/Makefile

@@ -66,7 +66,7 @@ BES2600_DRV_VERSION := bes2600_0.3.5_2024.0116
 ifeq ($(CONFIG_BES2600_CALIB_FROM_LINUX),y)
 FACTORY_CRC_CHECK                    ?= n
 STANDARD_FACTORY_EFUSE_FLAG          ?= y
-FACTORY_PATH                 ?= bes2600/bes2600_factory.txt
+FACTORY_PATH                 ?= /lib/firmware/bes2600_factory.txt
 endif
 
 # basic function

bes2600/bes2600_factory.c

@@ -12,7 +12,6 @@
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/fs.h>
-#include <linux/firmware.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/crc32.h>
@@ -138,32 +137,38 @@ static int bes2600_factory_crc_check(struct factory_t *factory_data)
  */
 static int factory_section_read_file(char *path, void *buffer)
 {
-	const struct firmware *fw;
+	int ret = 0;
-	int ret;
+	struct file *fp;
 
 	if (!path || !buffer) {
 		bes_err("%s NULL pointer err\n", __func__);
 		return -1;
 	}
 
-	bes_devel("requesting firmware-class %s\n", path);
+	bes_devel("reading %s \n", path);
 
-	ret = request_firmware(&fw, path, NULL);
+	fp = filp_open(path, O_RDONLY, 0); //S_IRUSR
-	if (ret) {
+	if (IS_ERR(fp)) {
-		bes_devel("BES2600: request_firmware(%s) failed: %d\n", path, ret);
+		bes_devel("BES2600 : can't open %s\n",path);
 		return -1;
 	}
 
-	if (fw->size == 0 || fw->size > FACTORY_MAX_SIZE) {
+	if (fp->f_inode->i_size <= 0 || fp->f_inode->i_size > FACTORY_MAX_SIZE) {
-		bes_err("bes2600_factory.txt size check failed, read_size: %zu max_size: %d\n",
+		bes_err(			"bes2600_factory.txt size check failed, read_size: %lld max_size: %d\n",
-			fw->size, FACTORY_MAX_SIZE);
+			fp->f_inode->i_size, FACTORY_MAX_SIZE);
-		release_firmware(fw);
+		filp_close(fp, NULL);
 		return -1;
 	}
 
-	memcpy(buffer, fw->data, fw->size);
+	ret = kernel_read(fp, buffer, fp->f_inode->i_size, &fp->f_pos);
-	ret = (int)fw->size;
+
-	release_firmware(fw);
+	filp_close(fp, NULL);
+
+	if (ret != fp->f_inode->i_size) {
+		bes_err("bes2600_factory.txt read fail\n");
+		ret = -1;
+	}
+
 	return ret;
 }
 

bes2600/bes_pwr.c

@@ -472,6 +472,7 @@ static int bes2600_pwr_enter_lp_mode(struct bes2600_common *hw_priv)
 	int i = 0;
 	struct bes2600_vif *priv;
 	int ret = 0;
+	int timeouts = 0;
 	char ip_str[20];
 	unsigned long status = 0;
 
@@ -528,22 +529,35 @@ static int bes2600_pwr_enter_lp_mode(struct bes2600_common *hw_priv)
 				if (ret) {
 					atomic_set(&hw_priv->bes_power.pm_set_in_process, 0);
 					bes_err("%s, set operation mode fail\n", __func__);
+					timeouts++;
+					continue;
 				}
 
 				/* wait power save mode changed indication */
 				status = wait_for_completion_timeout(&hw_priv->bes_power.pm_enter_cmpl, 5 * HZ);
 				atomic_set(&hw_priv->bes_power.pm_set_in_process, 0);
 				reinit_completion(&hw_priv->bes_power.pm_enter_cmpl);
-				if (!status)
+				if (!status) {
 					bes_err("%s, wait pm ind timeout\n", __func__);
+					timeouts++;
+				}
 			} else {
 				bes_devel("skip enter lp mode\n");
 			}
 		}
 	}
 
-	/* set device low power configuration */
+	/*
+	 * Enter the device-end of the LP transition only if every per-VIF
+	 * mac80211 handshake reached firmware-ACKed completion. Doing the
+	 * device-LP setup while any VIF is still pending leaves the driver
+	 * in an inconsistent state that cascades into SDIO TX errors on
+	 * the BES2600.
+	 */
+	if (timeouts == 0)
 		bes2600_pwr_device_enter_lp_mode(hw_priv);
+	else
+		ret = -ETIMEDOUT;
 
 	return ret;
 }