[PATCH] staging: fbtft: fb_ra8875: replace udelay with usleep_range

From: Selby Mashiki via B4 Relay

Date: Thu Jul 16 2026 - 07:09:02 EST


From: Selby Mashiki <mashikiselby@xxxxxxxxx>

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@xxxxxxxxx>
---
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@xxxxxxxxx>