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From:   Roman Beranek <me@crly.cz>
To:     Maxime Ripard <mripard@kernel.org>, Chen-Yu Tsai <wens@csie.org>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Samuel Holland <samuel@sholland.org>
Cc:     Roman Beranek <me@crly.cz>, Frank Oltmanns <frank@oltmanns.dev>,
        Icenowy Zheng <icenowy@aosc.io>, Ondrej Jirman <megi@xff.cz>,
        dri-devel@lists.freedesktop.org,
        linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: [PATCH v3 2/7] clk: sunxi-ng: a64: prevent CLK_TCON0 being reparented
Date:   Thu, 27 Apr 2023 11:16:06 +0200
Message-Id: <20230427091611.99044-3-me@crly.cz>
In-Reply-To: <20230427091611.99044-1-me@crly.cz>
References: <20230427091611.99044-1-me@crly.cz>
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TCON0's source clock can be fed from either pll-mipi, or pll-video0-2x,
however MIPI DSI output only seem to work when pll-mipi is selected and
thus some restriction have to be put on reparenting CLK_TCON0.

Functionally, there's no harm to other TCON0 users (LVDS, parallel RGB)
in also forcing them to settle on pll-mipi. The parent will be assigned
during boot based off of tcon0's DT node.

Signed-off-by: Roman Beranek <me@crly.cz>
---
 drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
index 41519185600a..044f301a8c61 100644
--- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
+++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
@@ -532,7 +532,8 @@ static const char * const tcon0_parents[] = { "pll-mipi", "pll-video0-2x" };
 static const u8 tcon0_table[] = { 0, 2, };
 static SUNXI_CCU_MUX_TABLE_WITH_GATE(tcon0_clk, "tcon0", tcon0_parents,
 				     tcon0_table, 0x118, 24, 3, BIT(31),
-				     CLK_SET_RATE_PARENT);
+				     CLK_SET_RATE_PARENT |
+				     CLK_SET_RATE_NO_REPARENT);
 
 static const char * const tcon1_parents[] = { "pll-video0", "pll-video1" };
 static const u8 tcon1_table[] = { 0, 2, };
-- 
2.34.1