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Date:   Wed, 26 Apr 2023 21:21:10 +0200
From:   Sam Ravnborg <sam@ravnborg.org>
To:     Thomas Zimmermann <tzimmermann@suse.de>
Cc:     deller@gmx.de, geert@linux-m68k.org, javierm@redhat.com,
        daniel@ffwll.ch, vgupta@kernel.org, chenhuacai@kernel.org,
        kernel@xen0n.name, davem@davemloft.net,
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        linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linux-arch@vger.kernel.org, linux-snps-arc@lists.infradead.org,
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        linux-parisc@vger.kernel.org
Subject: Re: [PATCH 0/5] fbdev: Move framebuffer I/O helpers to <asm/fb.h>
Message-ID: <20230426192110.GA3791243@ravnborg.org>
References: <20230426130420.19942-1-tzimmermann@suse.de>
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Hi Thomas.

On Wed, Apr 26, 2023 at 03:04:15PM +0200, Thomas Zimmermann wrote:
> Fbdev provides helpers for framebuffer I/O, such as fb_readl(),
> fb_writel() or fb_memcpy_to_fb(). The implementation of each helper
> depends on the architecture. It's still all located in fbdev's main
> header file <linux/fb.h>. Move all of it into each archtecture's
> <asm/fb.h>, with shared code in <asm-generic/fb.h>.

For once I think this cleanup is moving things in the wrong direction.

The fb_* helpers predates the generic io.h support and try to
add a generic layer for read read / write operations.

The right fix would be to migrate fb_* to use the io helpers
we have today - so we use the existing way to handle the architecture
specific details.

From a quick look there seems to be some challenges but the current
helpers that re-do part of io.h is not the way forward and hiding them
in arch/include/asm/fb.h seems counter productive.

	Sam