[media] s5p-fimc: Add support for alpha component configuration

On Exynos SoCs the FIMC IP allows to configure globally the alpha
component of all pixels for V4L2_PIX_FMT_RGB32, V4L2_PIX_FMT_RGB555
and V4L2_PIX_FMT_RGB444 image formats. This patch adds a v4l2 control
in order to let the applications control the alpha component value.

The alpha value range depends on the pixel format, for RGB32 it's
0..255 (8-bits), for RGB555 - 0..1 (1-bit) and for RGB444 - 0..15
(4-bits). The v4l2 control range is always 0..255 and the alpha
component data width is determined by currently set format on the
V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE buffer queue. The applications
need to match the alpha channel value range and the pixel format
since the driver will clamp the alpha component. Depending on
fourcc the valid alpha bits are:

 - V4L2_PIX_FMT_RGB555  [0]
 - V4L2_PIX_FMT_RGB444  [3:0]
 - V4L2_PIX_FMT_RGB32   [7:0]

When switching to a pixel format with smaller alpha component width
the currently set alpha value will be clamped to maximum value valid
for current format. When switching to a format with wider alpha the
alpha value remains unchanged.

The variant description data structure is extended with a new entry
so an additional control is created only where really supported by
the hardware.

V4L2_PIX_FMT_RGB555 and V4L2_PIX_FMT_RGB444 formats are only valid
for V4L2_BUF_TYPE_VIDEO_CAPTURE buffer queue.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 26 insertions, 4 deletions

diff --git a/drivers/media/video/s5p-fimc/fimc-core.h b/drivers/media/video/s5p-fimc/fimc-core.h
index c7f01c47b20f..4e20560c73d4 100644
--- a/drivers/media/video/s5p-fimc/fimc-core.h
+++ b/drivers/media/video/s5p-fimc/fimc-core.h
@@ -85,7 +85,9 @@ enum fimc_datapath {
 };
 
 enum fimc_color_fmt {
-	S5P_FIMC_RGB565 = 0x10,
+	S5P_FIMC_RGB444 = 0x10,
+	S5P_FIMC_RGB555,
+	S5P_FIMC_RGB565,
 	S5P_FIMC_RGB666,
 	S5P_FIMC_RGB888,
 	S5P_FIMC_RGB30_LOCAL,
@@ -160,8 +162,11 @@ struct fimc_fmt {
 	u16	colplanes;
 	u8	depth[VIDEO_MAX_PLANES];
 	u16	flags;
-#define FMT_FLAGS_CAM	(1 << 0)
-#define FMT_FLAGS_M2M	(1 << 1)
+#define FMT_FLAGS_CAM		(1 << 0)
+#define FMT_FLAGS_M2M_IN	(1 << 1)
+#define FMT_FLAGS_M2M_OUT	(1 << 2)
+#define FMT_FLAGS_M2M		(1 << 1 | 1 << 2)
+#define FMT_HAS_ALPHA		(1 << 3)
 };
 
 /**
@@ -283,6 +288,7 @@ struct fimc_frame {
 	struct fimc_addr	paddr;
 	struct fimc_dma_offset	dma_offset;
 	struct fimc_fmt		*fmt;
+	u8			alpha;
 };
 
 /**
@@ -387,6 +393,7 @@ struct samsung_fimc_variant {
 	unsigned int	has_cistatus2:1;
 	unsigned int	has_mainscaler_ext:1;
 	unsigned int	has_cam_if:1;
+	unsigned int	has_alpha:1;
 	struct fimc_pix_limit *pix_limit;
 	u16		min_inp_pixsize;
 	u16		min_out_pixsize;
@@ -482,7 +489,8 @@ struct fimc_dev {
  * @ctrl_handler:	v4l2 controls handler
  * @ctrl_rotate		image rotation control
  * @ctrl_hflip		horizontal flip control
- * @ctrl_vflip		vartical flip control
+ * @ctrl_vflip		vertical flip control
+ * @ctrl_alpha		RGB alpha control
  * @ctrls_rdy:		true if the control handler is initialized
  */
 struct fimc_ctx {
@@ -509,6 +517,7 @@ struct fimc_ctx {
 	struct v4l2_ctrl	*ctrl_rotate;
 	struct v4l2_ctrl	*ctrl_hflip;
 	struct v4l2_ctrl	*ctrl_vflip;
+	struct v4l2_ctrl	*ctrl_alpha;
 	bool			ctrls_rdy;
 };
 
@@ -578,6 +587,17 @@ static inline int tiled_fmt(struct fimc_fmt *fmt)
 	return fmt->fourcc == V4L2_PIX_FMT_NV12MT;
 }
 
+/* Return the alpha component bit mask */
+static inline int fimc_get_alpha_mask(struct fimc_fmt *fmt)
+{
+	switch (fmt->color) {
+	case S5P_FIMC_RGB444:	return 0x0f;
+	case S5P_FIMC_RGB555:	return 0x01;
+	case S5P_FIMC_RGB888:	return 0xff;
+	default:		return 0;
+	};
+}
+
 static inline void fimc_hw_clear_irq(struct fimc_dev *dev)
 {
 	u32 cfg = readl(dev->regs + S5P_CIGCTRL);
@@ -674,6 +694,7 @@ void fimc_hw_set_prescaler(struct fimc_ctx *ctx);
 void fimc_hw_set_mainscaler(struct fimc_ctx *ctx);
 void fimc_hw_en_capture(struct fimc_ctx *ctx);
 void fimc_hw_set_effect(struct fimc_ctx *ctx, bool active);
+void fimc_hw_set_rgb_alpha(struct fimc_ctx *ctx);
 void fimc_hw_set_in_dma(struct fimc_ctx *ctx);
 void fimc_hw_set_input_path(struct fimc_ctx *ctx);
 void fimc_hw_set_output_path(struct fimc_ctx *ctx);
@@ -695,6 +716,7 @@ int fimc_vidioc_enum_fmt_mplane(struct file *file, void *priv,
 int fimc_ctrls_create(struct fimc_ctx *ctx);
 void fimc_ctrls_delete(struct fimc_ctx *ctx);
 void fimc_ctrls_activate(struct fimc_ctx *ctx, bool active);
+void fimc_alpha_ctrl_update(struct fimc_ctx *ctx);
 int fimc_fill_format(struct fimc_frame *frame, struct v4l2_format *f);
 void fimc_adjust_mplane_format(struct fimc_fmt *fmt, u32 width, u32 height,
 			       struct v4l2_pix_format_mplane *pix);