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	Tue, 13 Jan 2026 17:53:52 +0000
Date: Tue, 13 Jan 2026 17:53:52 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Gideon Adjei <gideonadjei.dev@gmail.com>
Cc: Andy Shevchenko <andy@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Abdun Nihaal <abdun.nihaal@gmail.com>,
	Dan Carpenter <dan.carpenter@linaro.org>,
	Jianglei Nie <niejianglei2021@163.com>,
	dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
	linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: fbtft: Change udelay() to usleep_range()
Message-ID: <aWaGsGhS-nNrDjDA@casper.infradead.org>
References: <20260113172756.14744-1-gideonadjei.dev@gmail.com>
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In-Reply-To: <20260113172756.14744-1-gideonadjei.dev@gmail.com>

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?