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Date:   Fri, 30 Jun 2023 08:54:27 -0700
From:   Nathan Chancellor <nathan@kernel.org>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        Hans Verkuil <hverkuil-cisco@xs4all.nl>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, Zhou jie <zhoujie@nfschina.com>,
        llvm@lists.linux.dev
Subject: Re: [PATCH] media: wl128x: fix a clang warning
Message-ID: <20230630155427.GA2889176@dev-arch.thelio-3990X>
References: <6badd27ebfa718d5737f517f18b29a3e0f6e43f8.1687981726.git.mchehab@kernel.org>
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In-Reply-To: <6badd27ebfa718d5737f517f18b29a3e0f6e43f8.1687981726.git.mchehab@kernel.org>
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On Wed, Jun 28, 2023 at 09:48:53PM +0200, Mauro Carvalho Chehab wrote:
> Clang-16 produces this warning, which is fatal with CONFIG_WERROR:
> 
> 	../drivers/media/radio/wl128x/fmdrv_common.c:1237:19: error: variable 'cmd_cnt' set but not used [-Werror,-Wunused-but-set-variable]
> 	        int ret, fw_len, cmd_cnt;
> 	                         ^
> 	1 error generated.
> 
> What happens is that cmd_cnt tracks the amount of firmware data packets
> were transfered, which is printed only when debug is used.

Alternatively, fmdbg() could be defined with no_printk(), so that the
variable appears used in all configurations, but this does not seem
unreasonable either.

> Switch to use the firmware count, as the message is all about reporting
> a partial firmware transfer.
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
> ---
>  drivers/media/radio/wl128x/fmdrv_common.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/radio/wl128x/fmdrv_common.c b/drivers/media/radio/wl128x/fmdrv_common.c
> index cbd49dff6d74..b31b7ed60bbe 100644
> --- a/drivers/media/radio/wl128x/fmdrv_common.c
> +++ b/drivers/media/radio/wl128x/fmdrv_common.c
> @@ -1234,9 +1234,8 @@ static int fm_download_firmware(struct fmdev *fmdev, const u8 *fw_name)
>  	struct bts_action *action;
>  	struct bts_action_delay *delay;
>  	u8 *fw_data;
> -	int ret, fw_len, cmd_cnt;
> +	int ret, fw_len;
>  
> -	cmd_cnt = 0;
>  	set_bit(FM_FW_DW_INPROGRESS, &fmdev->flag);
>  
>  	ret = request_firmware(&fw_entry, fw_name,
> @@ -1272,7 +1271,6 @@ static int fm_download_firmware(struct fmdev *fmdev, const u8 *fw_name)
>  			if (ret)
>  				goto rel_fw;
>  
> -			cmd_cnt++;
>  			break;
>  
>  		case ACTION_DELAY:	/* Delay */
> @@ -1284,7 +1282,7 @@ static int fm_download_firmware(struct fmdev *fmdev, const u8 *fw_name)
>  		fw_data += (sizeof(struct bts_action) + (action->size));
>  		fw_len -= (sizeof(struct bts_action) + (action->size));
>  	}
> -	fmdbg("Firmware commands(%d) loaded to chip\n", cmd_cnt);
> +	fmdbg("Transfered only %d of %d bytes of the firmware to chip\n", fw_entry->size - fw_len, fw_entry->size);
>  rel_fw:
>  	release_firmware(fw_entry);
>  	clear_bit(FM_FW_DW_INPROGRESS, &fmdev->flag);
> -- 
> 2.41.0
>