drivers/media/platform/vsp1/vsp1_uds.c

   1 /*
   2  * vsp1_uds.c  --  R-Car VSP1 Up and Down Scaler
   3  *
   4  * Copyright (C) 2013-2014 Renesas Electronics Corporation
   5  *
   6  * Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/device.h>
  15 #include <linux/gfp.h>
  16
  17 #include <media/v4l2-subdev.h>
  18
  19 #include "vsp1.h"
  20 #include "vsp1_uds.h"
  21
  22 #define UDS_MIN_SIZE                            4U
  23 #define UDS_MAX_SIZE                            8190U
  24
  25 #define UDS_MIN_FACTOR                          0x0100
  26 #define UDS_MAX_FACTOR                          0xffff
  27
  28 /* -----------------------------------------------------------------------------
  29  * Device Access
  30  */
  31
  32 static inline void vsp1_uds_write(struct vsp1_uds *uds, u32 reg, u32 data)
  33 {
  34         vsp1_mod_write(&uds->entity, reg + uds->entity.index * VI6_UDS_OFFSET,
  35                        data);
  36 }
  37
  38 /* -----------------------------------------------------------------------------
  39  * Scaling Computation
  40  */
  41
  42 void vsp1_uds_set_alpha(struct vsp1_uds *uds, unsigned int alpha)
  43 {
  44         vsp1_uds_write(uds, VI6_UDS_ALPVAL, alpha << VI6_UDS_ALPVAL_VAL0_SHIFT);
  45 }
  46
  47 /*
  48  * uds_output_size - Return the output size for an input size and scaling ratio
  49  * @input: input size in pixels
  50  * @ratio: scaling ratio in U4.12 fixed-point format
  51  */
  52 static unsigned int uds_output_size(unsigned int input, unsigned int ratio)
  53 {
  54         if (ratio > 4096) {
  55                 /* Down-scaling */
  56                 unsigned int mp;
  57
  58                 mp = ratio / 4096;
  59                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  60
  61                 return (input - 1) / mp * mp * 4096 / ratio + 1;
  62         } else {
  63                 /* Up-scaling */
  64                 return (input - 1) * 4096 / ratio + 1;
  65         }
  66 }
  67
  68 /*
  69  * uds_output_limits - Return the min and max output sizes for an input size
  70  * @input: input size in pixels
  71  * @minimum: minimum output size (returned)
  72  * @maximum: maximum output size (returned)
  73  */
  74 static void uds_output_limits(unsigned int input,
  75                               unsigned int *minimum, unsigned int *maximum)
  76 {
  77         *minimum = max(uds_output_size(input, UDS_MAX_FACTOR), UDS_MIN_SIZE);
  78         *maximum = min(uds_output_size(input, UDS_MIN_FACTOR), UDS_MAX_SIZE);
  79 }
  80
  81 /*
  82  * uds_passband_width - Return the passband filter width for a scaling ratio
  83  * @ratio: scaling ratio in U4.12 fixed-point format
  84  */
  85 static unsigned int uds_passband_width(unsigned int ratio)
  86 {
  87         if (ratio >= 4096) {
  88                 /* Down-scaling */
  89                 unsigned int mp;
  90
  91                 mp = ratio / 4096;
  92                 mp = mp < 4 ? 1 : (mp < 8 ? 2 : 4);
  93
  94                 return 64 * 4096 * mp / ratio;
  95         } else {
  96                 /* Up-scaling */
  97                 return 64;
  98         }
  99 }
 100
 101 static unsigned int uds_compute_ratio(unsigned int input, unsigned int output)
 102 {
 103         /* TODO: This is an approximation that will need to be refined. */
 104         return (input - 1) * 4096 / (output - 1);
 105 }
 106
 107 /* -----------------------------------------------------------------------------
 108  * V4L2 Subdevice Pad Operations
 109  */
 110
 111 static int uds_enum_mbus_code(struct v4l2_subdev *subdev,
 112                               struct v4l2_subdev_pad_config *cfg,
 113                               struct v4l2_subdev_mbus_code_enum *code)
 114 {
 115         static const unsigned int codes[] = {
 116                 MEDIA_BUS_FMT_ARGB8888_1X32,
 117                 MEDIA_BUS_FMT_AYUV8_1X32,
 118         };
 119         struct vsp1_uds *uds = to_uds(subdev);
 120
 121         if (code->pad == UDS_PAD_SINK) {
 122                 if (code->index >= ARRAY_SIZE(codes))
 123                         return -EINVAL;
 124
 125                 code->code = codes[code->index];
 126         } else {
 127                 struct v4l2_subdev_pad_config *config;
 128                 struct v4l2_mbus_framefmt *format;
 129
 130                 config = vsp1_entity_get_pad_config(&uds->entity, cfg,
 131                                                     code->which);
 132                 if (!config)
 133                         return -EINVAL;
 134
 135                 /* The UDS can't perform format conversion, the sink format is
 136                  * always identical to the source format.
 137                  */
 138                 if (code->index)
 139                         return -EINVAL;
 140
 141                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 142                                                     UDS_PAD_SINK);
 143                 code->code = format->code;
 144         }
 145
 146         return 0;
 147 }
 148
 149 static int uds_enum_frame_size(struct v4l2_subdev *subdev,
 150                                struct v4l2_subdev_pad_config *cfg,
 151                                struct v4l2_subdev_frame_size_enum *fse)
 152 {
 153         struct vsp1_uds *uds = to_uds(subdev);
 154         struct v4l2_subdev_pad_config *config;
 155         struct v4l2_mbus_framefmt *format;
 156
 157         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fse->which);
 158         if (!config)
 159                 return -EINVAL;
 160
 161         format = vsp1_entity_get_pad_format(&uds->entity, config,
 162                                             UDS_PAD_SINK);
 163
 164         if (fse->index || fse->code != format->code)
 165                 return -EINVAL;
 166
 167         if (fse->pad == UDS_PAD_SINK) {
 168                 fse->min_width = UDS_MIN_SIZE;
 169                 fse->max_width = UDS_MAX_SIZE;
 170                 fse->min_height = UDS_MIN_SIZE;
 171                 fse->max_height = UDS_MAX_SIZE;
 172         } else {
 173                 uds_output_limits(format->width, &fse->min_width,
 174                                   &fse->max_width);
 175                 uds_output_limits(format->height, &fse->min_height,
 176                                   &fse->max_height);
 177         }
 178
 179         return 0;
 180 }
 181
 182 static int uds_get_format(struct v4l2_subdev *subdev,
 183                           struct v4l2_subdev_pad_config *cfg,
 184                           struct v4l2_subdev_format *fmt)
 185 {
 186         struct vsp1_uds *uds = to_uds(subdev);
 187         struct v4l2_subdev_pad_config *config;
 188
 189         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 190         if (!config)
 191                 return -EINVAL;
 192
 193         fmt->format = *vsp1_entity_get_pad_format(&uds->entity, config,
 194                                                   fmt->pad);
 195
 196         return 0;
 197 }
 198
 199 static void uds_try_format(struct vsp1_uds *uds,
 200                            struct v4l2_subdev_pad_config *config,
 201                            unsigned int pad, struct v4l2_mbus_framefmt *fmt)
 202 {
 203         struct v4l2_mbus_framefmt *format;
 204         unsigned int minimum;
 205         unsigned int maximum;
 206
 207         switch (pad) {
 208         case UDS_PAD_SINK:
 209                 /* Default to YUV if the requested format is not supported. */
 210                 if (fmt->code != MEDIA_BUS_FMT_ARGB8888_1X32 &&
 211                     fmt->code != MEDIA_BUS_FMT_AYUV8_1X32)
 212                         fmt->code = MEDIA_BUS_FMT_AYUV8_1X32;
 213
 214                 fmt->width = clamp(fmt->width, UDS_MIN_SIZE, UDS_MAX_SIZE);
 215                 fmt->height = clamp(fmt->height, UDS_MIN_SIZE, UDS_MAX_SIZE);
 216                 break;
 217
 218         case UDS_PAD_SOURCE:
 219                 /* The UDS scales but can't perform format conversion. */
 220                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 221                                                     UDS_PAD_SINK);
 222                 fmt->code = format->code;
 223
 224                 uds_output_limits(format->width, &minimum, &maximum);
 225                 fmt->width = clamp(fmt->width, minimum, maximum);
 226                 uds_output_limits(format->height, &minimum, &maximum);
 227                 fmt->height = clamp(fmt->height, minimum, maximum);
 228                 break;
 229         }
 230
 231         fmt->field = V4L2_FIELD_NONE;
 232         fmt->colorspace = V4L2_COLORSPACE_SRGB;
 233 }
 234
 235 static int uds_set_format(struct v4l2_subdev *subdev,
 236                           struct v4l2_subdev_pad_config *cfg,
 237                           struct v4l2_subdev_format *fmt)
 238 {
 239         struct vsp1_uds *uds = to_uds(subdev);
 240         struct v4l2_subdev_pad_config *config;
 241         struct v4l2_mbus_framefmt *format;
 242
 243         config = vsp1_entity_get_pad_config(&uds->entity, cfg, fmt->which);
 244         if (!config)
 245                 return -EINVAL;
 246
 247         uds_try_format(uds, config, fmt->pad, &fmt->format);
 248
 249         format = vsp1_entity_get_pad_format(&uds->entity, config, fmt->pad);
 250         *format = fmt->format;
 251
 252         if (fmt->pad == UDS_PAD_SINK) {
 253                 /* Propagate the format to the source pad. */
 254                 format = vsp1_entity_get_pad_format(&uds->entity, config,
 255                                                     UDS_PAD_SOURCE);
 256                 *format = fmt->format;
 257
 258                 uds_try_format(uds, config, UDS_PAD_SOURCE, format);
 259         }
 260
 261         return 0;
 262 }
 263
 264 /* -----------------------------------------------------------------------------
 265  * V4L2 Subdevice Operations
 266  */
 267
 268 static struct v4l2_subdev_pad_ops uds_pad_ops = {
 269         .init_cfg = vsp1_entity_init_cfg,
 270         .enum_mbus_code = uds_enum_mbus_code,
 271         .enum_frame_size = uds_enum_frame_size,
 272         .get_fmt = uds_get_format,
 273         .set_fmt = uds_set_format,
 274 };
 275
 276 static struct v4l2_subdev_ops uds_ops = {
 277         .pad    = &uds_pad_ops,
 278 };
 279
 280 /* -----------------------------------------------------------------------------
 281  * VSP1 Entity Operations
 282  */
 283
 284 static void uds_configure(struct vsp1_entity *entity)
 285 {
 286         struct vsp1_uds *uds = to_uds(&entity->subdev);
 287         const struct v4l2_mbus_framefmt *output;
 288         const struct v4l2_mbus_framefmt *input;
 289         unsigned int hscale;
 290         unsigned int vscale;
 291         bool multitap;
 292
 293         input = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 294                                            UDS_PAD_SINK);
 295         output = vsp1_entity_get_pad_format(&uds->entity, uds->entity.config,
 296                                             UDS_PAD_SOURCE);
 297
 298         hscale = uds_compute_ratio(input->width, output->width);
 299         vscale = uds_compute_ratio(input->height, output->height);
 300
 301         dev_dbg(uds->entity.vsp1->dev, "hscale %u vscale %u\n", hscale, vscale);
 302
 303         /* Multi-tap scaling can't be enabled along with alpha scaling when
 304          * scaling down with a factor lower than or equal to 1/2 in either
 305          * direction.
 306          */
 307         if (uds->scale_alpha && (hscale >= 8192 || vscale >= 8192))
 308                 multitap = false;
 309         else
 310                 multitap = true;
 311
 312         vsp1_uds_write(uds, VI6_UDS_CTRL,
 313                        (uds->scale_alpha ? VI6_UDS_CTRL_AON : 0) |
 314                        (multitap ? VI6_UDS_CTRL_BC : 0));
 315
 316         vsp1_uds_write(uds, VI6_UDS_PASS_BWIDTH,
 317                        (uds_passband_width(hscale)
 318                                 << VI6_UDS_PASS_BWIDTH_H_SHIFT) |
 319                        (uds_passband_width(vscale)
 320                                 << VI6_UDS_PASS_BWIDTH_V_SHIFT));
 321
 322         /* Set the scaling ratios and the output size. */
 323         vsp1_uds_write(uds, VI6_UDS_SCALE,
 324                        (hscale << VI6_UDS_SCALE_HFRAC_SHIFT) |
 325                        (vscale << VI6_UDS_SCALE_VFRAC_SHIFT));
 326         vsp1_uds_write(uds, VI6_UDS_CLIP_SIZE,
 327                        (output->width << VI6_UDS_CLIP_SIZE_HSIZE_SHIFT) |
 328                        (output->height << VI6_UDS_CLIP_SIZE_VSIZE_SHIFT));
 329 }
 330
 331 static const struct vsp1_entity_operations uds_entity_ops = {
 332         .configure = uds_configure,
 333 };
 334
 335 /* -----------------------------------------------------------------------------
 336  * Initialization and Cleanup
 337  */
 338
 339 struct vsp1_uds *vsp1_uds_create(struct vsp1_device *vsp1, unsigned int index)
 340 {
 341         struct vsp1_uds *uds;
 342         char name[6];
 343         int ret;
 344
 345         uds = devm_kzalloc(vsp1->dev, sizeof(*uds), GFP_KERNEL);
 346         if (uds == NULL)
 347                 return ERR_PTR(-ENOMEM);
 348
 349         uds->entity.ops = &uds_entity_ops;
 350         uds->entity.type = VSP1_ENTITY_UDS;
 351         uds->entity.index = index;
 352
 353         sprintf(name, "uds.%u", index);
 354         ret = vsp1_entity_init(vsp1, &uds->entity, name, 2, &uds_ops);
 355         if (ret < 0)
 356                 return ERR_PTR(ret);
 357
 358         return uds;
 359 }