Re: [PATCH 1/3] atmel_lcdfb: fix 16-bpp modes on older SOCs

[Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>]

On 13:28 Mon 10 Dec     , Johan Hovold wrote:
> Fix regression introduced by commit 787f9fd23283 ("atmel_lcdfb: support
> 16bit BGR:565 mode, remove unsupported 15bit modes") which broke 16-bpp
> modes for older SOCs which use IBGR:555 (msb is intensity) rather
> than BGR:565.
> 
> Use SOC-type to determine the pixel layout.
> 
> Tested on custom at91sam9263-board.
> 
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Johan Hovold <jhovold@gmail.com>
> ---
>  drivers/video/atmel_lcdfb.c | 22 +++++++++++++++-------
>  include/video/atmel_lcdc.h  |  1 +
>  2 files changed, 16 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
> index 1505539..1f68fa6 100644
> --- a/drivers/video/atmel_lcdfb.c
> +++ b/drivers/video/atmel_lcdfb.c
> @@ -422,17 +422,22 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
>  			= var->bits_per_pixel;
>  		break;
>  	case 16:
> +		/* Older SOCs use IBGR:555 rather than BGR:565. */
> +		if (sinfo->have_intensity_bit)
> +			var->green.length = 5;
> +		else
> +			var->green.length = 6;
> +
>  		if (sinfo->lcd_wiring_mode = ATMEL_LCDC_WIRING_RGB) {
> -			/* RGB:565 mode */
> -			var->red.offset = 11;
> +			/* RGB:5X5 mode */
> +			var->red.offset = var->green.length + 5;
>  			var->blue.offset = 0;
>  		} else {
> -			/* BGR:565 mode */
> +			/* BGR:5X5 mode */
>  			var->red.offset = 0;
> -			var->blue.offset = 11;
> +			var->blue.offset = var->green.length + 5;
>  		}
>  		var->green.offset = 5;
> -		var->green.length = 6;
>  		var->red.length = var->blue.length = 5;
>  		break;
>  	case 32:
> @@ -679,8 +684,7 @@ static int atmel_lcdfb_setcolreg(unsigned int regno, unsigned int red,
>  
>  	case FB_VISUAL_PSEUDOCOLOR:
>  		if (regno < 256) {
> -			if (cpu_is_at91sam9261() || cpu_is_at91sam9263()
> -			    || cpu_is_at91sam9rl()) {
> +			if (sinfo->have_intensity_bit) {
>  				/* old style I+BGR:555 */
>  				val  = ((red   >> 11) & 0x001f);
>  				val |= ((green >>  6) & 0x03e0);
> @@ -870,6 +874,10 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
>  	}
>  	sinfo->info = info;
>  	sinfo->pdev = pdev;
> +	if (cpu_is_at91sam9261() || cpu_is_at91sam9263() ||
> +							cpu_is_at91sam9rl()) {
> +		sinfo->have_intensity_bit = true;
> +	}
nack

you need to drop the cpu_is as this can only be use now for the core

use platform_device_id to indetify the IP as done on at91-i2c as we can not
detect the IP version

Best Regards,
J.
>  
>  	strcpy(info->fix.id, sinfo->pdev->name);
>  	info->flags = ATMEL_LCDFB_FBINFO_DEFAULT;
> diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h
> index 28447f1..5f0e234 100644
> --- a/include/video/atmel_lcdc.h
> +++ b/include/video/atmel_lcdc.h
> @@ -62,6 +62,7 @@ struct atmel_lcdfb_info {
>  	void (*atmel_lcdfb_power_control)(int on);
>  	struct fb_monspecs	*default_monspecs;
>  	u32			pseudo_palette[16];
> +	bool			have_intensity_bit;
>  };
>  
>  #define ATMEL_LCDC_DMABADDR1	0x00
> -- 
> 1.8.0
>