Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH v3 1/2] media: tpg: Add function to return colors' order
 of test image
To:     Kaaira Gupta <kgupta@es.iitr.ac.in>,
        Helen Koike <helen.koike@collabora.com>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        Kieran Bingham <kieran.bingham@ideasonboard.com>
References: <20200618190506.11892-1-kgupta@es.iitr.ac.in>
 <20200618190506.11892-2-kgupta@es.iitr.ac.in>
From:   Hans Verkuil <hverkuil@xs4all.nl>
Message-ID: <8268357e-6b47-a11c-c00f-3c8fa0582a7d@xs4all.nl>
Date:   Mon, 22 Jun 2020 12:45:23 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.9.0
MIME-Version: 1.0
In-Reply-To: <20200618190506.11892-2-kgupta@es.iitr.ac.in>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 18/06/2020 21:05, Kaaira Gupta wrote:
> Currently there is no method to know the correct order of the colors for
> a test image generated by tpg. Write a function that returns a string of
> colors' order given a tpg. It returns a NULL pointer in case of test
> patterns which do not have a well defined colors' order. Hence add a
> NULL check for text in tpg_gen_text().
> 
> Signed-off-by: Kaaira Gupta <kgupta@es.iitr.ac.in>
> Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
> ---
>  drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 32 +++++++++++++++++--
>  include/media/tpg/v4l2-tpg.h                  |  1 +
>  2 files changed, 31 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> index 50f1e0b28b25..31e6044a4104 100644
> --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c
> @@ -1959,12 +1959,14 @@ void tpg_gen_text(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
>  	unsigned step = V4L2_FIELD_HAS_T_OR_B(tpg->field) ? 2 : 1;
>  	unsigned div = step;
>  	unsigned first = 0;
> -	unsigned len = strlen(text);
> +	unsigned len;
>  	unsigned p;
>  
> -	if (font8x16 == NULL || basep == NULL)
> +	if (font8x16 == NULL || basep == NULL || text == NULL)
>  		return;
>  
> +	len = strlen(text);
> +
>  	/* Checks if it is possible to show string */
>  	if (y + 16 >= tpg->compose.height || x + 8 >= tpg->compose.width)
>  		return;
> @@ -2006,6 +2008,32 @@ void tpg_gen_text(const struct tpg_data *tpg, u8 *basep[TPG_MAX_PLANES][2],
>  }
>  EXPORT_SYMBOL_GPL(tpg_gen_text);
>  
> +char *tpg_g_color_order(const struct tpg_data *tpg)

This returns a const char *.

> +{
> +	#define COLORBAR(order) #order "white, yellow, cyan, green, magenta, red, blue, black"
> +
> +	switch (tpg->pattern) {
> +	case TPG_PAT_75_COLORBAR:
> +	case TPG_PAT_100_COLORBAR:
> +	case TPG_PAT_CSC_COLORBAR:
> +		return COLORBAR(Left to right:);
> +	case TPG_PAT_100_HCOLORBAR:

Just combine this with the other and just return the sequence:

		return "White, Yellow, Cyan, Green, Magenta, Red, Blue, Black";

It's obvious from the pattern that three are from left to right and one is from
top to bottom. No need to mention that here.

Regards,

	Hans

> +		return COLORBAR(Top to bottom:);
> +	case TPG_PAT_BLACK:
> +		return "Black";
> +	case TPG_PAT_WHITE:
> +		return "White";
> +	case TPG_PAT_RED:
> +		return "Red";
> +	case TPG_PAT_GREEN:
> +		return "Green";
> +	case TPG_PAT_BLUE:
> +		return "Blue";
> +	default:
> +		return NULL;
> +	}
> +}
> +
>  void tpg_update_mv_step(struct tpg_data *tpg)
>  {
>  	int factor = tpg->mv_hor_mode > TPG_MOVE_NONE ? -1 : 1;
> diff --git a/include/media/tpg/v4l2-tpg.h b/include/media/tpg/v4l2-tpg.h
> index eb191e85d363..4f79cac87b85 100644
> --- a/include/media/tpg/v4l2-tpg.h
> +++ b/include/media/tpg/v4l2-tpg.h
> @@ -252,6 +252,7 @@ void tpg_fillbuffer(struct tpg_data *tpg, v4l2_std_id std,
>  bool tpg_s_fourcc(struct tpg_data *tpg, u32 fourcc);
>  void tpg_s_crop_compose(struct tpg_data *tpg, const struct v4l2_rect *crop,
>  		const struct v4l2_rect *compose);
> +char *tpg_g_color_order(const struct tpg_data *tpg);
>  
>  static inline void tpg_s_pattern(struct tpg_data *tpg, enum tpg_pattern pattern)
>  {
>