[PATCH 3/3] drm/sun4i: tcon: hand over the duty to keep TCON0 clock to CCU on A64

[Frank Oltmanns]

From: Icenowy Zheng <icenowy at aosc.io>

As the A64 CCU driver has already the ability to keep TCON0 clock stable
when HDMI changes its parent's clock, do not protect TCON0 clock on A64
in the TCON driver to allow PLL-Video0 gets changed by HDMI (the CCU
will then restore the TCON0 clock rate).

Signed-off-by: Icenowy Zheng <icenowy at aosc.io>
---
 drivers/gpu/drm/sun4i/sun4i_tcon.c | 15 +++++++++++++--
 drivers/gpu/drm/sun4i/sun4i_tcon.h |  1 +
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
index c44d5f3350d1..6f2d544c5f29 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
@@ -110,9 +110,11 @@ static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
 
 	if (enabled) {
 		clk_prepare_enable(clk);
-		clk_rate_exclusive_get(clk);
+		if (!tcon->quirks->clk_kept_by_ccu)
+			clk_rate_exclusive_get(clk);
 	} else {
-		clk_rate_exclusive_put(clk);
+		if (!tcon->quirks->clk_kept_by_ccu)
+			clk_rate_exclusive_put(clk);
 		clk_disable_unprepare(clk);
 	}
 }
@@ -1562,6 +1564,14 @@ static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
 	.supports_lvds		= true,
 };
 
+static const struct sun4i_tcon_quirks sun50i_a64_lcd_quirks = {
+	.supports_lvds		= true,
+	.has_channel_0		= true,
+	.clk_kept_by_ccu	= true,
+	.dclk_min_div		= 1,
+	.setup_lvds_phy		= sun6i_tcon_setup_lvds_phy,
+};
+
 static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
 	.supports_lvds		= true,
 	.has_channel_0		= true,
@@ -1620,6 +1630,7 @@ const struct of_device_id sun4i_tcon_of_table[] = {
 	{ .compatible = "allwinner,sun9i-a80-tcon-tv", .data = &sun9i_a80_tcon_tv_quirks },
 	{ .compatible = "allwinner,sun20i-d1-tcon-lcd", .data = &sun20i_d1_lcd_quirks },
 	{ .compatible = "allwinner,sun20i-d1-tcon-tv", .data = &sun8i_r40_tv_quirks },
+	{ .compatible = "allwinner,sun50i-a64-tcon-lcd", .data = &sun50i_a64_lcd_quirks },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, sun4i_tcon_of_table);
diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h
index 864d70b9d242..7ba3df9e27df 100644
--- a/drivers/gpu/drm/sun4i/sun4i_tcon.h
+++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h
@@ -250,6 +250,7 @@ struct sun4i_tcon_quirks {
 	bool    needs_edp_reset; /* a80 edp reset needed for tcon0 access */
 	bool	supports_lvds;   /* Does the TCON support an LVDS output? */
 	bool	polarity_in_ch0; /* some tcon1 channels have polarity bits in tcon0 pol register */
+	bool	clk_kept_by_ccu; /* On A64 we rely on CCU to keep TCON0 clock stable */
 	u8	dclk_min_div;	/* minimum divider for TCON0 DCLK */
 
 	/* callback to handle tcon muxing options */

-- 
2.41.0