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Tue, 13 Jan 2026 09:28:10 -0800 (PST) Received: from ubuntu.localdomain ([154.161.61.30]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-432bd0dacdcsm44792388f8f.1.2026.01.13.09.28.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Jan 2026 09:28:09 -0800 (PST) From: Gideon Adjei To: Andy Shevchenko , Greg Kroah-Hartman Cc: Abdun Nihaal , Dan Carpenter , Jianglei Nie , Matthew Wilcox , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, Gideon Adjei Subject: [PATCH] staging: fbtft: Change udelay() to usleep_range() Date: Tue, 13 Jan 2026 09:27:56 -0800 Message-Id: <20260113172756.14744-1-gideonadjei.dev@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-fbdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Replace udelay() calls >= 100us with usleep_range() to avoid busy-waiting. This allows the scheduler to run other tasks while waiting. Signed-off-by: Gideon Adjei --- drivers/staging/fbtft/fb_tinylcd.c | 2 +- drivers/staging/fbtft/fb_upd161704.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/staging/fbtft/fb_tinylcd.c b/drivers/staging/fbtft/fb_tinylcd.c index 9469248f2c50..ee8d6b10374a 100644 --- a/drivers/staging/fbtft/fb_tinylcd.c +++ b/drivers/staging/fbtft/fb_tinylcd.c @@ -41,7 +41,7 @@ static int init_display(struct fbtft_par *par) 0x00, 0x35, 0x33, 0x00, 0x00, 0x00); write_reg(par, MIPI_DCS_SET_PIXEL_FORMAT, 0x55); write_reg(par, MIPI_DCS_EXIT_SLEEP_MODE); - udelay(250); + usleep_range(250, 400); write_reg(par, MIPI_DCS_SET_DISPLAY_ON); return 0; diff --git a/drivers/staging/fbtft/fb_upd161704.c b/drivers/staging/fbtft/fb_upd161704.c index c680160d6380..aed5cc7cabde 100644 --- a/drivers/staging/fbtft/fb_upd161704.c +++ b/drivers/staging/fbtft/fb_upd161704.c @@ -32,7 +32,7 @@ static int init_display(struct fbtft_par *par) /* oscillator start */ write_reg(par, 0x003A, 0x0001); /*Oscillator 0: stop, 1: operation */ - udelay(100); + usleep_range(100, 200); /* y-setting */ write_reg(par, 0x0024, 0x007B); /* amplitude setting */ @@ -60,7 +60,7 @@ static int init_display(struct fbtft_par *par) /* Power supply setting */ write_reg(par, 0x0019, 0x0000); /* DC/DC output setting */ - udelay(200); + usleep_range(200, 400); write_reg(par, 0x001A, 0x1000); /* DC/DC frequency setting */ write_reg(par, 0x001B, 0x0023); /* DC/DC rising setting */ write_reg(par, 0x001C, 0x0C01); /* Regulator voltage setting */ -- 2.34.1