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From: "Duc-Long, Le" <duclong.linux@gmail.com>
To: Mauro Carvalho Chehab <mchehab@kernel.org>,
	linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] media: tc358746: fix the pll calculating function
Date: Sat, 14 Oct 2023 20:19:46 -0400	[thread overview]
Message-ID: <20231015001946.GA10485@fpga> (raw)

Following formula of Pll_clk in 5.2 section, 50th page of
TC358746AXBG/748XBG/748IXBG Functional Specification Rev 1.1 document.
The formula of fout is as below:
	fout = refclk * mul / (prediv * postdiv)

Remove "p" to avoid using 2 times of prediv in pll calculating function.

Signed-off-by: Duc-Long, Le <duclong.linux@gmail.com>
---
 drivers/media/i2c/tc358746.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/tc358746.c b/drivers/media/i2c/tc358746.c
index 566f5eaddd57..4f54773886cc 100644
--- a/drivers/media/i2c/tc358746.c
+++ b/drivers/media/i2c/tc358746.c
@@ -839,14 +839,14 @@ static unsigned long tc358746_find_pll_settings(struct tc358746 *tc358746,
 		if (fin < 4 * HZ_PER_MHZ || fin > 40 * HZ_PER_MHZ)
 			continue;
 
-		tmp = fout * p * postdiv;
+		tmp = fout * postdiv;
 		do_div(tmp, fin);
 		mul = tmp;
 		if (mul > 511)
 			continue;
 
 		tmp = mul * fin;
-		do_div(tmp, p * postdiv);
+		do_div(tmp, postdiv);
 
 		delta = abs(fout - tmp);
 		if (delta < min_delta) {
-- 
2.17.1


                 reply	other threads:[~2023-10-15  0:19 UTC|newest]

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