gpu: ipu-v3: Add rotation mode conversion utilities

Add two functions:

- ipu_degrees_to_rot_mode(): converts a degrees, hflip, and vflip setting
  to an IPU rotation mode.
- ipu_rot_mode_to_degrees(): converts an IPU rotation mode with given hflip
  and vflip settings to degrees.
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>

drivers/gpu/ipu-v3/ipu-common.c

@@ -114,6 +114,70 @@ enum ipu_color_space ipu_mbus_code_to_colorspace(u32 mbus_code)
 }
 EXPORT_SYMBOL_GPL(ipu_mbus_code_to_colorspace);
 
+int ipu_degrees_to_rot_mode(enum ipu_rotate_mode *mode, int degrees,
+			    bool hflip, bool vflip)
+{
+	u32 r90, vf, hf;
+
+	switch (degrees) {
+	case 0:
+		vf = hf = r90 = 0;
+		break;
+	case 90:
+		vf = hf = 0;
+		r90 = 1;
+		break;
+	case 180:
+		vf = hf = 1;
+		r90 = 0;
+		break;
+	case 270:
+		vf = hf = r90 = 1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	hf ^= (u32)hflip;
+	vf ^= (u32)vflip;
+
+	*mode = (enum ipu_rotate_mode)((r90 << 2) | (hf << 1) | vf);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_degrees_to_rot_mode);
+
+int ipu_rot_mode_to_degrees(int *degrees, enum ipu_rotate_mode mode,
+			    bool hflip, bool vflip)
+{
+	u32 r90, vf, hf;
+
+	r90 = ((u32)mode >> 2) & 0x1;
+	hf = ((u32)mode >> 1) & 0x1;
+	vf = ((u32)mode >> 0) & 0x1;
+	hf ^= (u32)hflip;
+	vf ^= (u32)vflip;
+
+	switch ((enum ipu_rotate_mode)((r90 << 2) | (hf << 1) | vf)) {
+	case IPU_ROTATE_NONE:
+		*degrees = 0;
+		break;
+	case IPU_ROTATE_90_RIGHT:
+		*degrees = 90;
+		break;
+	case IPU_ROTATE_180:
+		*degrees = 180;
+		break;
+	case IPU_ROTATE_90_LEFT:
+		*degrees = 270;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_rot_mode_to_degrees);
+
 struct ipuv3_channel *ipu_idmac_get(struct ipu_soc *ipu, unsigned num)
 {
 	struct ipuv3_channel *channel;

include/video/imx-ipu-v3.h

@@ -301,6 +301,10 @@ int ipu_smfc_set_watermark(struct ipu_smfc *smfc, u32 set_level, u32 clr_level);
 enum ipu_color_space ipu_drm_fourcc_to_colorspace(u32 drm_fourcc);
 enum ipu_color_space ipu_pixelformat_to_colorspace(u32 pixelformat);
 enum ipu_color_space ipu_mbus_code_to_colorspace(u32 mbus_code);
+int ipu_degrees_to_rot_mode(enum ipu_rotate_mode *mode, int degrees,
+			    bool hflip, bool vflip);
+int ipu_rot_mode_to_degrees(int *degrees, enum ipu_rotate_mode mode,
+			    bool hflip, bool vflip);
 
 struct ipu_client_platformdata {
 	int csi;