drm/rockchip: lvds: switch to FIELD_PREP_WM16 macro

The era of hand-rolled HIWORD_UPDATE macros is over, at least for those
drivers that use constant masks.

Remove rockchip_lvds.h's own HIWORD_UPDATE macro, and replace all
instances of it with hw_bitfield.h's FIELD_PREP_WM16 macro, which gives
us more error checking.

For the slightly-less-trivial case of the 2-bit width instance, the
results were checked during development to match all possible input
values (0 to 3, inclusive).

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>

Author: Nicolas Frattaroli

drivers/gpu/drm/rockchip/rockchip_lvds.h

@@ -9,6 +9,9 @@
 #ifndef _ROCKCHIP_LVDS_
 #define _ROCKCHIP_LVDS_
 
+#include <linux/bits.h>
+#include <linux/hw_bitfield.h>
+
 #define RK3288_LVDS_CH0_REG0			0x00
 #define RK3288_LVDS_CH0_REG0_LVDS_EN		BIT(7)
 #define RK3288_LVDS_CH0_REG0_TTL_EN		BIT(6)
@@ -106,18 +109,16 @@
 #define LVDS_VESA_18				2
 #define LVDS_JEIDA_18				3
 
-#define HIWORD_UPDATE(v, h, l)  ((GENMASK(h, l) << 16) | ((v) << (l)))
-
 #define PX30_LVDS_GRF_PD_VO_CON0		0x434
-#define   PX30_LVDS_TIE_CLKS(val)		HIWORD_UPDATE(val,  8,  8)
-#define   PX30_LVDS_INVERT_CLKS(val)		HIWORD_UPDATE(val,  9,  9)
-#define   PX30_LVDS_INVERT_DCLK(val)		HIWORD_UPDATE(val,  5,  5)
+#define   PX30_LVDS_TIE_CLKS(val)		FIELD_PREP_WM16(BIT(8), (val))
+#define   PX30_LVDS_INVERT_CLKS(val)		FIELD_PREP_WM16(BIT(9), (val))
+#define   PX30_LVDS_INVERT_DCLK(val)		FIELD_PREP_WM16(BIT(5), (val))
 
 #define PX30_LVDS_GRF_PD_VO_CON1		0x438
-#define   PX30_LVDS_FORMAT(val)			HIWORD_UPDATE(val, 14, 13)
-#define   PX30_LVDS_MODE_EN(val)		HIWORD_UPDATE(val, 12, 12)
-#define   PX30_LVDS_MSBSEL(val)			HIWORD_UPDATE(val, 11, 11)
-#define   PX30_LVDS_P2S_EN(val)			HIWORD_UPDATE(val,  6,  6)
-#define   PX30_LVDS_VOP_SEL(val)		HIWORD_UPDATE(val,  1,  1)
+#define   PX30_LVDS_FORMAT(val)			FIELD_PREP_WM16(GENMASK(14, 13), (val))
+#define   PX30_LVDS_MODE_EN(val)		FIELD_PREP_WM16(BIT(12), (val))
+#define   PX30_LVDS_MSBSEL(val)			FIELD_PREP_WM16(BIT(11), (val))
+#define   PX30_LVDS_P2S_EN(val)			FIELD_PREP_WM16(BIT(6), (val))
+#define   PX30_LVDS_VOP_SEL(val)		FIELD_PREP_WM16(BIT(1), (val))
 
 #endif /* _ROCKCHIP_LVDS_ */