drm/sun4i: hdmi ddc clk: Fix size of m divider

m divider in DDC clock register is 4 bits wide. Fix that.

Fixes: 9c568101 ("drm/sun4i: Add HDMI support")
Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200413095457.1176754-1-jernej.skrabec@siol.net

drivers/gpu/drm/sun4i/sun4i_hdmi.h

@@ -148,7 +148,7 @@
 #define SUN4I_HDMI_DDC_CMD_IMPLICIT_WRITE	3
 
 #define SUN4I_HDMI_DDC_CLK_REG		0x528
-#define SUN4I_HDMI_DDC_CLK_M(m)			(((m) & 0x7) << 3)
+#define SUN4I_HDMI_DDC_CLK_M(m)			(((m) & 0xf) << 3)
 #define SUN4I_HDMI_DDC_CLK_N(n)			((n) & 0x7)
 
 #define SUN4I_HDMI_DDC_LINE_CTRL_REG	0x540

drivers/gpu/drm/sun4i/sun4i_hdmi_ddc_clk.c

@@ -33,7 +33,7 @@ static unsigned long sun4i_ddc_calc_divider(unsigned long rate,
 	unsigned long best_rate = 0;
 	u8 best_m = 0, best_n = 0, _m, _n;
 
-	for (_m = 0; _m < 8; _m++) {
+	for (_m = 0; _m < 16; _m++) {
 		for (_n = 0; _n < 8; _n++) {
 			unsigned long tmp_rate;