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From: Selby Mashiki via B4 Relay <devnull+mashikiselby.gmail.com@kernel.org>
To: Andy Shevchenko <andy@kernel.org>,
	 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org,
	 linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org,
	 Selby Mashiki <mashikiselby@gmail.com>
Subject: [PATCH] staging: fbtft: fb_ra8875: replace udelay with usleep_range
Date: Thu, 16 Jul 2026 13:08:33 +0200	[thread overview]
Message-ID: <20260716-staging-testing-v1-1-2ebc0c6bb27a@gmail.com> (raw)

From: Selby Mashiki <mashikiselby@gmail.com>

udelay() busy-waits for the specified duration, consuming CPU cycles
unnecessarily. usleep_range() is preferred for delays that can sleep,
as it allows the scheduler to run other tasks during the wait.

Replace two instances of udelay(100) with usleep_range(100, 200) to
use the preferred sleeping delay function.

Signed-off-by: Selby Mashiki <mashikiselby@gmail.com>
---
 drivers/staging/fbtft/fb_ra8875.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/fbtft/fb_ra8875.c b/drivers/staging/fbtft/fb_ra8875.c
index 0ab1de664..d2400bb44 100644
--- a/drivers/staging/fbtft/fb_ra8875.c
+++ b/drivers/staging/fbtft/fb_ra8875.c
@@ -210,7 +210,7 @@ static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
 	}
 	len--;
 
-	udelay(100);
+	usleep_range(100, 200);
 
 	if (len) {
 		buf = (u8 *)par->buf;
@@ -231,7 +231,7 @@ static void write_reg8_bus8(struct fbtft_par *par, int len, ...)
 
 	/* restore user spi-speed */
 	par->fbtftops.write = fbtft_write_spi;
-	udelay(100);
+	usleep_range(100, 200);
 }
 
 static int write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)

---
base-commit: 64276d9bfe4d1fdd5cf2636f1065f7ea55c2defb
change-id: 20260716-staging-testing-b1b81d63d0d1

Best regards,
--  
Selby Mashiki <mashikiselby@gmail.com>



             reply	other threads:[~2026-07-16 11:08 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-16 11:08 Selby Mashiki via B4 Relay [this message]
2026-07-16 18:37 ` [PATCH] staging: fbtft: fb_ra8875: replace udelay with usleep_range Andy Shevchenko
     [not found] <20260218174737.86994-1-tomasz.unger.ref@yahoo.pl>
2026-02-18 17:47 ` tomasz.unger
2026-02-19  7:30   ` Andy Shevchenko
  -- strict thread matches above, loose matches on Subject: below --
2025-10-20 19:15 Olle Lukowski
2025-10-21  7:37 ` Greg Kroah-Hartman
2025-10-21  8:12   ` Olle Lukowski
2025-10-21  8:50 ` Andy Shevchenko

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