[PATCH] brcmfmac: firmware: Fix firmware loading

[PATCH] brcmfmac: firmware: Fix firmware loading

[Linus Walleij]

The patch that would first try the board-specific firmware
had a bug because the fallback would not be called: the
asynchronous interface is used meaning request_firmware_nowait()
returns 0 immediately.

Harden the firmware loading like this:

- If we cannot build an alt_path (like if no board_type is
  specified) just request the first firmware without any
  suffix, like in the past.

- If the lookup of a board specific firmware fails, we get
  a NULL fw in the async callback, so just try again without
  the alt_path. Use a static variable to check that we do not
  try this indefinitely.

- Rename the brcm_fw_request_done to brcm_fw_request_done_first
  reflecting the fact that this callback is only used for the
  first (main) firmware file, and drop the unnecessary
  prototype.

Fixes: 5ff013914c62 ("brcmfmac: firmware: Allow per-board firmware binaries")
Cc: Dmitry Osipenko <digetx@gmail.com>
Cc: Stefan Hansson <newbyte@disroot.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 .../broadcom/brcm80211/brcmfmac/firmware.c    | 29 +++++++++++++------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
index adfdfc654b10..71ca4a517e42 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
@@ -431,8 +431,6 @@ struct brcmf_fw {
 	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
 };
 
-static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
-
 #ifdef CONFIG_EFI
 /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
  * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
@@ -638,11 +636,26 @@ static int brcmf_fw_request_firmware(const struct firmware **fw,
 	return request_firmware(fw, cur->path, fwctx->dev);
 }
 
-static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
+static void brcmf_fw_request_done_first(const struct firmware *fw, void *ctx)
 {
 	struct brcmf_fw *fwctx = ctx;
+	struct brcmf_fw_item *first = &fwctx->req->items[0];
+	static bool retry = true;
 	int ret;
 
+	/*Something failed with the first firmware request , such as not
+	 * getting the per-board firmware. Retry this, now using the less
+	 * specific path for the first firmware item, i.e. without the board
+	 * suffix.
+	 */
+	if (!fw && retry) {
+		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
+					      fwctx->dev, GFP_KERNEL, fwctx,
+					      brcmf_fw_request_done_first);
+		retry = false;
+		return;
+	}
+
 	ret = brcmf_fw_complete_request(fw, fwctx);
 
 	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
@@ -702,17 +715,15 @@ int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
 	if (alt_path) {
 		ret = request_firmware_nowait(THIS_MODULE, true, alt_path,
 					      fwctx->dev, GFP_KERNEL, fwctx,
-					      brcmf_fw_request_done);
+					      brcmf_fw_request_done_first);
 		kfree(alt_path);
-	}
-	/* Else try canonical path */
-	if (ret) {
+	} else {
 		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
 					      fwctx->dev, GFP_KERNEL, fwctx,
-					      brcmf_fw_request_done);
+					      brcmf_fw_request_done_first);
 	}
 	if (ret < 0)
-		brcmf_fw_request_done(NULL, fwctx);
+		brcmf_fw_request_done_first(NULL, fwctx);
 
 	return 0;
 }
-- 
2.31.1

Re: [PATCH] brcmfmac: firmware: Fix firmware loading

[Arend van Spriel]

On 04-08-2021 01:27, Linus Walleij wrote:
> The patch that would first try the board-specific firmware
> had a bug because the fallback would not be called: the
> asynchronous interface is used meaning request_firmware_nowait()
> returns 0 immediately.
> 
> Harden the firmware loading like this:
> 
> - If we cannot build an alt_path (like if no board_type is
>    specified) just request the first firmware without any
>    suffix, like in the past.
> 
> - If the lookup of a board specific firmware fails, we get
>    a NULL fw in the async callback, so just try again without
>    the alt_path. Use a static variable to check that we do not
>    try this indefinitely.
> 
> - Rename the brcm_fw_request_done to brcm_fw_request_done_first
>    reflecting the fact that this callback is only used for the
>    first (main) firmware file, and drop the unnecessary
>    prototype.
> 
> Fixes: 5ff013914c62 ("brcmfmac: firmware: Allow per-board firmware binaries")
> Cc: Dmitry Osipenko <digetx@gmail.com>
> Cc: Stefan Hansson <newbyte@disroot.org>

One remark below, but you may add...

Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>   .../broadcom/brcm80211/brcmfmac/firmware.c    | 29 +++++++++++++------
>   1 file changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> index adfdfc654b10..71ca4a517e42 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> @@ -431,8 +431,6 @@ struct brcmf_fw {
>   	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
>   };
>   
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
> -
>   #ifdef CONFIG_EFI
>   /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
>    * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
> @@ -638,11 +636,26 @@ static int brcmf_fw_request_firmware(const struct firmware **fw,
>   	return request_firmware(fw, cur->path, fwctx->dev);
>   }
>   
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
> +static void brcmf_fw_request_done_first(const struct firmware *fw, void *ctx)
>   {
>   	struct brcmf_fw *fwctx = ctx;
> +	struct brcmf_fw_item *first = &fwctx->req->items[0];
> +	static bool retry = true;

using a static seems tricky to me when there are multiple supported 
devices in a system (like in mine ;-)). Probably better to add the flag 
in struct brcmf_fw.

Regards,
Arend

Re: [PATCH] brcmfmac: firmware: Fix firmware loading

[Dmitry Osipenko]

04.08.2021 02:27, Linus Walleij пишет:
> The patch that would first try the board-specific firmware
> had a bug because the fallback would not be called: the
> asynchronous interface is used meaning request_firmware_nowait()
> returns 0 immediately.
> 
> Harden the firmware loading like this:
> 
> - If we cannot build an alt_path (like if no board_type is
>   specified) just request the first firmware without any
>   suffix, like in the past.
> 
> - If the lookup of a board specific firmware fails, we get
>   a NULL fw in the async callback, so just try again without
>   the alt_path. Use a static variable to check that we do not
>   try this indefinitely.
> 
> - Rename the brcm_fw_request_done to brcm_fw_request_done_first
>   reflecting the fact that this callback is only used for the
>   first (main) firmware file, and drop the unnecessary
>   prototype.
> 
> Fixes: 5ff013914c62 ("brcmfmac: firmware: Allow per-board firmware binaries")
> Cc: Dmitry Osipenko <digetx@gmail.com>
> Cc: Stefan Hansson <newbyte@disroot.org>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  .../broadcom/brcm80211/brcmfmac/firmware.c    | 29 +++++++++++++------
>  1 file changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> index adfdfc654b10..71ca4a517e42 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c
> @@ -431,8 +431,6 @@ struct brcmf_fw {
>  	void (*done)(struct device *dev, int err, struct brcmf_fw_request *req);
>  };
>  
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx);
> -
>  #ifdef CONFIG_EFI
>  /* In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
>   * to specify "worldwide" compatible settings, but these 2 ccode-s do not work
> @@ -638,11 +636,26 @@ static int brcmf_fw_request_firmware(const struct firmware **fw,
>  	return request_firmware(fw, cur->path, fwctx->dev);
>  }
>  
> -static void brcmf_fw_request_done(const struct firmware *fw, void *ctx)
> +static void brcmf_fw_request_done_first(const struct firmware *fw, void *ctx)
>  {
>  	struct brcmf_fw *fwctx = ctx;
> +	struct brcmf_fw_item *first = &fwctx->req->items[0];
> +	static bool retry = true;
>  	int ret;
>  
> +	/*Something failed with the first firmware request , such as not

There is a problem with whitespaces here.

> +	 * getting the per-board firmware. Retry this, now using the less
> +	 * specific path for the first firmware item, i.e. without the board
> +	 * suffix.
> +	 */
> +	if (!fw && retry) {
> +		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
> +					      fwctx->dev, GFP_KERNEL, fwctx,
> +					      brcmf_fw_request_done_first);
> +		retry = false;
> +		return;
> +	}
> +
>  	ret = brcmf_fw_complete_request(fw, fwctx);
>  
>  	while (ret == 0 && ++fwctx->curpos < fwctx->req->n_items) {
> @@ -702,17 +715,15 @@ int brcmf_fw_get_firmwares(struct device *dev, struct brcmf_fw_request *req,
>  	if (alt_path) {
>  		ret = request_firmware_nowait(THIS_MODULE, true, alt_path,
>  					      fwctx->dev, GFP_KERNEL, fwctx,
> -					      brcmf_fw_request_done);
> +					      brcmf_fw_request_done_first);
>  		kfree(alt_path);
> -	}
> -	/* Else try canonical path */
> -	if (ret) {
> +	} else {
>  		ret = request_firmware_nowait(THIS_MODULE, true, first->path,
>  					      fwctx->dev, GFP_KERNEL, fwctx,
> -					      brcmf_fw_request_done);
> +					      brcmf_fw_request_done_first);
>  	}
>  	if (ret < 0)
> -		brcmf_fw_request_done(NULL, fwctx);
> +		brcmf_fw_request_done_first(NULL, fwctx);
>  
>  	return 0;
>  }
> 

Works, thanks!

Re: [PATCH] brcmfmac: firmware: Fix firmware loading

[Linus Walleij]

On Wed, Aug 4, 2021 at 4:57 PM Dmitry Osipenko <digetx@gmail.com> wrote:

> Works, thanks!

I record this as Tested-by! :)

Yours,
Linus Walleij