drm/armada: improve Dove clock selection

Improve the Dove (Armada 510) LCD clock selection and divider
calculation, limiting to the valid divisor values, and reporting an
error if the clock is not achievable within the bounds of HDMI
clocking requirements.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

1 files changed, 20 insertions, 1 deletions

diff --git a/drivers/gpu/drm/armada/armada_crtc.h b/drivers/gpu/drm/armada/armada_crtc.h
index 08761ff01739..fb4aa48da60c 100644
--- a/drivers/gpu/drm/armada/armada_crtc.h
+++ b/drivers/gpu/drm/armada/armada_crtc.h
@@ -39,10 +39,10 @@ struct armada_variant;
 struct armada_crtc {
 	struct drm_crtc		crtc;
 	const struct armada_variant *variant;
+	void			*variant_data;
 	unsigned		num;
 	void __iomem		*base;
 	struct clk		*clk;
-	struct clk		*extclk[2];
 	struct {
 		uint32_t	spu_v_h_total;
 		uint32_t	spu_v_porch;
@@ -75,6 +75,25 @@ struct armada_crtc {
 
 void armada_drm_crtc_update_regs(struct armada_crtc *, struct armada_regs *);
 
+struct armada_clocking_params {
+	unsigned long permillage_min;
+	unsigned long permillage_max;
+	u32 settable;
+	u32 div_max;
+};
+
+struct armada_clk_result {
+	unsigned long desired_clk_hz;
+	struct clk *clk;
+	u32 div;
+};
+
+int armada_crtc_select_clock(struct armada_crtc *dcrtc,
+			     struct armada_clk_result *res,
+			     const struct armada_clocking_params *params,
+			     struct clk *clks[], size_t num_clks,
+			     unsigned long desired_khz);
+
 extern struct platform_driver armada_lcd_platform_driver;
 
 #endif