linux-kernel - Re: [PATCH] staging: fbtft: Change udelay() to usleep

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Message-ID: <aWaGsGhS-nNrDjDA@casper.infradead.org>
Date: Tue, 13 Jan 2026 17:53:52 +0000
From: Matthew Wilcox <willy@...radead.org>
To: Gideon Adjei <gideonadjei.dev@...il.com>
Cc: Andy Shevchenko <andy@...nel.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Abdun Nihaal <abdun.nihaal@...il.com>,
	Dan Carpenter <dan.carpenter@...aro.org>,
	Jianglei Nie <niejianglei2021@....com>,
	dri-devel@...ts.freedesktop.org, linux-fbdev@...r.kernel.org,
	linux-staging@...ts.linux.dev, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] staging: fbtft: Change udelay() to usleep_range()

On Tue, Jan 13, 2026 at 09:27:56AM -0800, Gideon Adjei wrote:
> Replace udelay() calls >= 100us with usleep_range() to avoid busy-waiting.
> This allows the scheduler to run other tasks while waiting.

Your commit message omits how you know it's safe to sleep in these
situations.  Are we holding a spinlock or being called in interrupt
context, for example?