wil6210: prevent device memory access while in reset or suspend

Accessing some of the memory of the device while the device is
resetting or suspending may cause unexpected error as the HW is still
not in a stable state. Prevent this access to guarantee successful
read/write memory operations.

Signed-off-by: Ahmad Masri <amasri@codeaurora.org>
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 6 insertions, 12 deletions

diff --git a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
index dc33a0b4c3fa..772cb00c2002 100644
--- a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
+++ b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2015,2017 Qualcomm Atheros, Inc.
- * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2019, The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -57,7 +57,7 @@ static int wil_fw_get_crash_dump_bounds(struct wil6210_priv *wil,
 
 int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
 {
-	int i;
+	int i, rc;
 	const struct fw_map *map;
 	void *data;
 	u32 host_min, dump_size, offset, len;
@@ -73,14 +73,9 @@ int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
 		return -EINVAL;
 	}
 
-	set_bit(wil_status_collecting_dumps, wil->status);
-	if (test_bit(wil_status_suspending, wil->status) ||
-	    test_bit(wil_status_suspended, wil->status) ||
-	    test_bit(wil_status_resetting, wil->status)) {
-		wil_err(wil, "cannot collect fw dump during suspend/reset\n");
-		clear_bit(wil_status_collecting_dumps, wil->status);
-		return -EINVAL;
-	}
+	rc = wil_mem_access_lock(wil);
+	if (rc)
+		return rc;
 
 	/* copy to crash dump area */
 	for (i = 0; i < ARRAY_SIZE(fw_mapping); i++) {
@@ -100,8 +95,7 @@ int wil_fw_copy_crash_dump(struct wil6210_priv *wil, void *dest, u32 size)
 		wil_memcpy_fromio_32((void * __force)(dest + offset),
 				     (const void __iomem * __force)data, len);
 	}
-
-	clear_bit(wil_status_collecting_dumps, wil->status);
+	wil_mem_access_unlock(wil);
 
 	return 0;
 }