Re: [PATCH] staging: fbtft: fb_tinylcd: replace udelay() with usleep_range()

[Dan Carpenter]

On Wed, Mar 11, 2026 at 02:24:07PM +0000, Anas Iqbal wrote:
> Replace udelay() with usleep_range() for a 250 microsecond delay
> as recommended by checkpatch.pl. usleep_range() avoids busy
> waiting and allows the scheduler to schedule other tasks.
> 
> Signed-off-by: Anas Iqbal <mohd.abd.6602@xxxxxxxxx>
> ---
>  drivers/staging/fbtft/fb_tinylcd.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/fbtft/fb_tinylcd.c b/drivers/staging/fbtft/fb_tinylcd.c
> index 9469248f2c50..51e6493b050f 100644
> --- a/drivers/staging/fbtft/fb_tinylcd.c
> +++ b/drivers/staging/fbtft/fb_tinylcd.c
> @@ -38,10 +38,10 @@ static int init_display(struct fbtft_par *par)
>  	write_reg(par, 0xE5, 0x00);
>  	write_reg(par, 0xF0, 0x36, 0xA5, 0x53);
>  	write_reg(par, 0xE0, 0x00, 0x35, 0x33, 0x00, 0x00, 0x00,
> -		       0x00, 0x35, 0x33, 0x00, 0x00, 0x00);
> +		  0x00, 0x35, 0x33, 0x00, 0x00, 0x00);

Don't do this.
1) It's unrelated.
2) The previous alignment was done deliberate to make it easier to read.
   Checkpatch is not perfect so don't always do what it says.

>  	write_reg(par, MIPI_DCS_SET_PIXEL_FORMAT, 0x55);
>  	write_reg(par, MIPI_DCS_EXIT_SLEEP_MODE);
> -	udelay(250);
> +	usleep_range(250, 500);

Do a search for init_display on lore

https://lore.kernel.org/all/?q=init_display

regards,
dan carpenter