Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / media / platform / vsp1 / vsp1_uds.c
diff --git a/kernel/drivers/media/platform/vsp1/vsp1_uds.c b/kernel/drivers/media/platform/vsp1/vsp1_uds.c
new file mode 100644 (file)
index 0000000..ccc8243
--- /dev/null
@@ -0,0 +1,357 @@
+/*
+ * vsp1_uds.c  --  R-Car VSP1 Up and Down Scaler
+ *
+ * Copyright (C) 2013-2014 Renesas Electronics Corporation
+ *
+ * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/gfp.h>
+
+#include <media/v4l2-subdev.h>
+
+#include "vsp1.h"
+#include "vsp1_uds.h"
+
+#define UDS_MIN_SIZE                           4U
+#define UDS_MAX_SIZE                           8190U
+
+#define UDS_MIN_FACTOR                         0x0100
+#define UDS_MAX_FACTOR                         0xffff
+
+/* -----------------------------------------------------------------------------
+ * Device Access
+ */
+
+static inline u32 vsp1_uds_read(struct vsp1_uds *uds, u32 reg)
+{
+       return vsp1_read(uds->entity.vsp1,
+                        reg + uds->entity.index * VI6_UDS_OFFSET);
+}
+
+static inline void vsp1_uds_write(struct vsp1_uds *uds, u32 reg, u32 data)
+{
+       vsp1_write(uds->entity.vsp1,
+                  reg + uds->entity.index * VI6_UDS_OFFSET, data);
+}
+
+/* -----------------------------------------------------------------------------
+ * Scaling Computation
+ */
+
+void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha)
+{
+       vsp1_uds_write(uds, VI6_UDS_ALPVAL, alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
+}
+
+/*
+ * uds_output_size - Return the output size for an input size and scaling ratio
+ * @input: input size in pixels
+ * @ratio: scaling ratio in U4.12 fixed-point format
+ */
+static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
+{
+       if (ratio > 4096) {
+               /* Down-scaling */
+               unsigned int mp;
+
+               mp = ratio / 4096;
+               mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
+
+               return (input - 1) / mp * mp * 4096 / ratio + 1;
+       } else {
+               /* Up-scaling */
+               return (input - 1) * 4096 / ratio + 1;
+       }
+}
+
+/*
+ * uds_output_limits - Return the min and max output sizes for an input size
+ * @input: input size in pixels
+ * @minimum: minimum output size (returned)
+ * @maximum: maximum output size (returned)
+ */
+static void uds_output_limits(unsigned int input,
+                             unsigned int *minimum, unsigned int *maximum)
+{
+       *minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
+       *maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
+}
+
+/*
+ * uds_passband_width - Return the passband filter width for a scaling ratio
+ * @ratio: scaling ratio in U4.12 fixed-point format
+ */
+static unsigned int uds_passband_width(unsigned int ratio)
+{
+       if (ratio >= 4096) {
+               /* Down-scaling */
+               unsigned int mp;
+
+               mp = ratio / 4096;
+               mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
+
+               return 64 * 4096 * mp / ratio;
+       } else {
+               /* Up-scaling */
+               return 64;
+       }
+}
+
+static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
+{
+       /* TODO: This is an approximation that will need to be refined. */
+       return (input - 1) * 4096 / (output - 1);
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 Subdevice Core Operations
+ */
+
+static int uds_s_stream(struct v4l2_subdev *subdev, int enable)
+{
+       struct vsp1_uds *uds = to_uds(subdev);
+       const struct v4l2_mbus_framefmt *output;
+       const struct v4l2_mbus_framefmt *input;
+       unsigned int hscale;
+       unsigned int vscale;
+       bool multitap;
+
+       if (!enable)
+               return 0;
+
+       input = &uds->entity.formats[UDS_PAD_SINK];
+       output = &uds->entity.formats[UDS_PAD_SOURCE];
+
+       hscale = uds_compute_ratio(input->width, output->width);
+       vscale = uds_compute_ratio(input->height, output->height);
+
+       dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
+
+       /* Multi-tap scaling can't be enabled along with alpha scaling when
+        * scaling down with a factor lower than or equal to 1/2 in either
+        * direction.
+        */
+       if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
+               multitap = false;
+       else
+               multitap = true;
+
+       vsp1_uds_write(uds, VI6_UDS_CTRL,
+                      (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
+                      (multitap ? VI6_UDS_CTRL_BC : 0));
+
+       vsp1_uds_write(uds, VI6_UDS_PASS_BWIDTH,
+                      (uds_passband_width(hscale)
+                               << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
+                      (uds_passband_width(vscale)
+                               << VI6_UDS_PASS_BWIDTH_V_SHIFT));
+
+       /* Set the scaling ratios and the output size. */
+       vsp1_uds_write(uds, VI6_UDS_SCALE,
+                      (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
+                      (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
+       vsp1_uds_write(uds, VI6_UDS_CLIP_SIZE,
+                      (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
+                      (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
+
+       return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 Subdevice Pad Operations
+ */
+
+static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
+                             struct v4l2_subdev_pad_config *cfg,
+                             struct v4l2_subdev_mbus_code_enum *code)
+{
+       static const unsigned int codes[] = {
+               MEDIA_BUS_FMT_ARGB8888_1X32,
+               MEDIA_BUS_FMT_AYUV8_1X32,
+       };
+       struct vsp1_uds *uds = to_uds(subdev);
+
+       if (code->pad == UDS_PAD_SINK) {
+               if (code->index >= ARRAY_SIZE(codes))
+                       return -EINVAL;
+
+               code->code = codes[code->index];
+       } else {
+               struct v4l2_mbus_framefmt *format;
+
+               /* The UDS can't perform format conversion, the sink format is
+                * always identical to the source format.
+                */
+               if (code->index)
+                       return -EINVAL;
+
+               format = vsp1_entity_get_pad_format(&uds->entity, cfg,
+                                                   UDS_PAD_SINK, code->which);
+               code->code = format->code;
+       }
+
+       return 0;
+}
+
+static int uds_enum_frame_size(struct v4l2_subdev *subdev,
+                              struct v4l2_subdev_pad_config *cfg,
+                              struct v4l2_subdev_frame_size_enum *fse)
+{
+       struct vsp1_uds *uds = to_uds(subdev);
+       struct v4l2_mbus_framefmt *format;
+
+       format = vsp1_entity_get_pad_format(&uds->entity, cfg,
+                                           UDS_PAD_SINK, fse->which);
+
+       if (fse->index || fse->code != format->code)
+               return -EINVAL;
+
+       if (fse->pad == UDS_PAD_SINK) {
+               fse->min_width = UDS_MIN_SIZE;
+               fse->max_width = UDS_MAX_SIZE;
+               fse->min_height = UDS_MIN_SIZE;
+               fse->max_height = UDS_MAX_SIZE;
+       } else {
+               uds_output_limits(format->width, &fse->min_width,
+                                 &fse->max_width);
+               uds_output_limits(format->height, &fse->min_height,
+                                 &fse->max_height);
+       }
+
+       return 0;
+}
+
+static int uds_get_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
+                         struct v4l2_subdev_format *fmt)
+{
+       struct vsp1_uds *uds = to_uds(subdev);
+
+       fmt->format = *vsp1_entity_get_pad_format(&uds->entity, cfg, fmt->pad,
+                                                 fmt->which);
+
+       return 0;
+}
+
+static void uds_try_format(struct vsp1_uds *uds, struct v4l2_subdev_pad_config *cfg,
+                          unsigned int pad, struct v4l2_mbus_framefmt *fmt,
+                          enum v4l2_subdev_format_whence which)
+{
+       struct v4l2_mbus_framefmt *format;
+       unsigned int minimum;
+       unsigned int maximum;
+
+       switch (pad) {
+       case UDS_PAD_SINK:
+               /* Default to YUV if the requested format is not supported. */
+               if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
+                   fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
+                       fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
+
+               fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
+               fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
+               break;
+
+       case UDS_PAD_SOURCE:
+               /* The UDS scales but can't perform format conversion. */
+               format = vsp1_entity_get_pad_format(&uds->entity, cfg,
+                                                   UDS_PAD_SINK, which);
+               fmt->code = format->code;
+
+               uds_output_limits(format->width, &minimum, &maximum);
+               fmt->width = clamp(fmt->width, minimum, maximum);
+               uds_output_limits(format->height, &minimum, &maximum);
+               fmt->height = clamp(fmt->height, minimum, maximum);
+               break;
+       }
+
+       fmt->field = V4L2_FIELD_NONE;
+       fmt->colorspace = V4L2_COLORSPACE_SRGB;
+}
+
+static int uds_set_format(struct v4l2_subdev *subdev, struct v4l2_subdev_pad_config *cfg,
+                         struct v4l2_subdev_format *fmt)
+{
+       struct vsp1_uds *uds = to_uds(subdev);
+       struct v4l2_mbus_framefmt *format;
+
+       uds_try_format(uds, cfg, fmt->pad, &fmt->format, fmt->which);
+
+       format = vsp1_entity_get_pad_format(&uds->entity, cfg, fmt->pad,
+                                           fmt->which);
+       *format = fmt->format;
+
+       if (fmt->pad == UDS_PAD_SINK) {
+               /* Propagate the format to the source pad. */
+               format = vsp1_entity_get_pad_format(&uds->entity, cfg,
+                                                   UDS_PAD_SOURCE, fmt->which);
+               *format = fmt->format;
+
+               uds_try_format(uds, cfg, UDS_PAD_SOURCE, format, fmt->which);
+       }
+
+       return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 Subdevice Operations
+ */
+
+static struct v4l2_subdev_video_ops uds_video_ops = {
+       .s_stream = uds_s_stream,
+};
+
+static struct v4l2_subdev_pad_ops uds_pad_ops = {
+       .enum_mbus_code = uds_enum_mbus_code,
+       .enum_frame_size = uds_enum_frame_size,
+       .get_fmt = uds_get_format,
+       .set_fmt = uds_set_format,
+};
+
+static struct v4l2_subdev_ops uds_ops = {
+       .video  = &uds_video_ops,
+       .pad    = &uds_pad_ops,
+};
+
+/* -----------------------------------------------------------------------------
+ * Initialization and Cleanup
+ */
+
+struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
+{
+       struct v4l2_subdev *subdev;
+       struct vsp1_uds *uds;
+       int ret;
+
+       uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
+       if (uds == NULL)
+               return ERR_PTR(-ENOMEM);
+
+       uds->entity.type = VSP1_ENTITY_UDS;
+       uds->entity.index = index;
+
+       ret = vsp1_entity_init(vsp1, &uds->entity, 2);
+       if (ret < 0)
+               return ERR_PTR(ret);
+
+       /* Initialize the V4L2 subdev. */
+       subdev = &uds->entity.subdev;
+       v4l2_subdev_init(subdev, &uds_ops);
+
+       subdev->entity.ops = &vsp1_media_ops;
+       subdev->internal_ops = &vsp1_subdev_internal_ops;
+       snprintf(subdev->name, sizeof(subdev->name), "%s uds.%u",
+                dev_name(vsp1->dev), index);
+       v4l2_set_subdevdata(subdev, uds);
+       subdev->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+
+       vsp1_entity_init_formats(subdev, NULL);
+
+       return uds;
+}