include/drm/drm_encoder.h

   1 /*
   2  * Copyright (c) 2016 Intel Corporation
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that copyright
   7  * notice and this permission notice appear in supporting documentation, and
   8  * that the name of the copyright holders not be used in advertising or
   9  * publicity pertaining to distribution of the software without specific,
  10  * written prior permission.  The copyright holders make no representations
  11  * about the suitability of this software for any purpose.  It is provided "as
  12  * is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  20  * OF THIS SOFTWARE.
  21  */
  22
  23 #ifndef __DRM_ENCODER_H__
  24 #define __DRM_ENCODER_H__
  25
  26 #include <linux/list.h>
  27 #include <linux/ctype.h>
  28 #include <drm/drm_crtc.h>
  29 #include <drm/drm_mode.h>
  30 #include <drm/drm_mode_object.h>
  31 #include <drm/drm_util.h>
  32
  33 struct drm_encoder;
  34
  35 /**
  36  * struct drm_encoder_funcs - encoder controls
  37  *
  38  * Encoders sit between CRTCs and connectors.
  39  */
  40 struct drm_encoder_funcs {
  41         /**
  42          * @reset:
  43          *
  44          * Reset encoder hardware and software state to off. This function isn't
  45          * called by the core directly, only through drm_mode_config_reset().
  46          * It's not a helper hook only for historical reasons.
  47          */
  48         void (*reset)(struct drm_encoder *encoder);
  49
  50         /**
  51          * @destroy:
  52          *
  53          * Clean up encoder resources. This is only called at driver unload time
  54          * through drm_mode_config_cleanup() since an encoder cannot be
  55          * hotplugged in DRM.
  56          */
  57         void (*destroy)(struct drm_encoder *encoder);
  58
  59         /**
  60          * @late_register:
  61          *
  62          * This optional hook can be used to register additional userspace
  63          * interfaces attached to the encoder like debugfs interfaces.
  64          * It is called late in the driver load sequence from drm_dev_register().
  65          * Everything added from this callback should be unregistered in
  66          * the early_unregister callback.
  67          *
  68          * Returns:
  69          *
  70          * 0 on success, or a negative error code on failure.
  71          */
  72         int (*late_register)(struct drm_encoder *encoder);
  73
  74         /**
  75          * @early_unregister:
  76          *
  77          * This optional hook should be used to unregister the additional
  78          * userspace interfaces attached to the encoder from
  79          * @late_register. It is called from drm_dev_unregister(),
  80          * early in the driver unload sequence to disable userspace access
  81          * before data structures are torndown.
  82          */
  83         void (*early_unregister)(struct drm_encoder *encoder);
  84 };
  85
  86 /**
  87  * struct drm_encoder - central DRM encoder structure
  88  * @dev: parent DRM device
  89  * @head: list management
  90  * @base: base KMS object
  91  * @name: human readable name, can be overwritten by the driver
  92  * @funcs: control functions, can be NULL for simple managed encoders
  93  * @helper_private: mid-layer private data
  94  *
  95  * CRTCs drive pixels to encoders, which convert them into signals
  96  * appropriate for a given connector or set of connectors.
  97  */
  98 struct drm_encoder {
  99         struct drm_device *dev;
 100         struct list_head head;
 101
 102         struct drm_mode_object base;
 103         char *name;
 104         /**
 105          * @encoder_type:
 106          *
 107          * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
 108          * encoder types are defined thus far:
 109          *
 110          * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
 111          *
 112          * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
 113          *
 114          * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
 115          *   with a proprietary parallel connector.
 116          *
 117          * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
 118          *   Component, SCART).
 119          *
 120          * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
 121          *
 122          * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
 123          *
 124          * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
 125          *   bus.
 126          *
 127          * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
 128          *   mutliple DP MST streams to share one physical encoder.
 129          */
 130         int encoder_type;
 131
 132         /**
 133          * @index: Position inside the mode_config.list, can be used as an array
 134          * index. It is invariant over the lifetime of the encoder.
 135          */
 136         unsigned index;
 137
 138         /**
 139          * @possible_crtcs: Bitmask of potential CRTC bindings, using
 140          * drm_crtc_index() as the index into the bitfield. The driver must set
 141          * the bits for all &drm_crtc objects this encoder can be connected to
 142          * before calling drm_dev_register().
 143          *
 144          * You will get a WARN if you get this wrong in the driver.
 145          *
 146          * Note that since CRTC objects can't be hotplugged the assigned indices
 147          * are stable and hence known before registering all objects.
 148          */
 149         uint32_t possible_crtcs;
 150
 151         /**
 152          * @possible_clones: Bitmask of potential sibling encoders for cloning,
 153          * using drm_encoder_index() as the index into the bitfield. The driver
 154          * must set the bits for all &drm_encoder objects which can clone a
 155          * &drm_crtc together with this encoder before calling
 156          * drm_dev_register(). Drivers should set the bit representing the
 157          * encoder itself, too. Cloning bits should be set such that when two
 158          * encoders can be used in a cloned configuration, they both should have
 159          * each another bits set.
 160          *
 161          * As an exception to the above rule if the driver doesn't implement
 162          * any cloning it can leave @possible_clones set to 0. The core will
 163          * automagically fix this up by setting the bit for the encoder itself.
 164          *
 165          * You will get a WARN if you get this wrong in the driver.
 166          *
 167          * Note that since encoder objects can't be hotplugged the assigned indices
 168          * are stable and hence known before registering all objects.
 169          */
 170         uint32_t possible_clones;
 171
 172         /**
 173          * @crtc: Currently bound CRTC, only really meaningful for non-atomic
 174          * drivers.  Atomic drivers should instead check
 175          * &drm_connector_state.crtc.
 176          */
 177         struct drm_crtc *crtc;
 178
 179         /**
 180          * @bridge_chain: Bridges attached to this encoder. Drivers shall not
 181          * access this field directly.
 182          */
 183         struct list_head bridge_chain;
 184
 185         const struct drm_encoder_funcs *funcs;
 186         const struct drm_encoder_helper_funcs *helper_private;
 187 };
 188
 189 #define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
 190
 191 __printf(5, 6)
 192 int drm_encoder_init(struct drm_device *dev,
 193                      struct drm_encoder *encoder,
 194                      const struct drm_encoder_funcs *funcs,
 195                      int encoder_type, const char *name, ...);
 196
 197 __printf(6, 7)
 198 void *__drmm_encoder_alloc(struct drm_device *dev,
 199                            size_t size, size_t offset,
 200                            const struct drm_encoder_funcs *funcs,
 201                            int encoder_type,
 202                            const char *name, ...);
 203
 204 /**
 205  * drmm_encoder_alloc - Allocate and initialize an encoder
 206  * @dev: drm device
 207  * @type: the type of the struct which contains struct &drm_encoder
 208  * @member: the name of the &drm_encoder within @type
 209  * @funcs: callbacks for this encoder (optional)
 210  * @encoder_type: user visible type of the encoder
 211  * @name: printf style format string for the encoder name, or NULL for default name
 212  *
 213  * Allocates and initializes an encoder. Encoder should be subclassed as part of
 214  * driver encoder objects. Cleanup is automatically handled through registering
 215  * drm_encoder_cleanup() with drmm_add_action().
 216  *
 217  * The @drm_encoder_funcs.destroy hook must be NULL.
 218  *
 219  * Returns:
 220  * Pointer to new encoder, or ERR_PTR on failure.
 221  */
 222 #define drmm_encoder_alloc(dev, type, member, funcs, encoder_type, name, ...) \
 223         ((type *)__drmm_encoder_alloc(dev, sizeof(type), \
 224                                       offsetof(type, member), funcs, \
 225                                       encoder_type, name, ##__VA_ARGS__))
 226
 227 /**
 228  * drmm_plain_encoder_alloc - Allocate and initialize an encoder
 229  * @dev: drm device
 230  * @funcs: callbacks for this encoder (optional)
 231  * @encoder_type: user visible type of the encoder
 232  * @name: printf style format string for the encoder name, or NULL for default name
 233  *
 234  * This is a simplified version of drmm_encoder_alloc(), which only allocates
 235  * and returns a struct drm_encoder instance, with no subclassing.
 236  *
 237  * Returns:
 238  * Pointer to the new drm_encoder struct, or ERR_PTR on failure.
 239  */
 240 #define drmm_plain_encoder_alloc(dev, funcs, encoder_type, name, ...) \
 241         ((struct drm_encoder *) \
 242          __drmm_encoder_alloc(dev, sizeof(struct drm_encoder), \
 243                               0, funcs, encoder_type, name, ##__VA_ARGS__))
 244
 245 /**
 246  * drm_encoder_index - find the index of a registered encoder
 247  * @encoder: encoder to find index for
 248  *
 249  * Given a registered encoder, return the index of that encoder within a DRM
 250  * device's list of encoders.
 251  */
 252 static inline unsigned int drm_encoder_index(const struct drm_encoder *encoder)
 253 {
 254         return encoder->index;
 255 }
 256
 257 /**
 258  * drm_encoder_mask - find the mask of a registered encoder
 259  * @encoder: encoder to find mask for
 260  *
 261  * Given a registered encoder, return the mask bit of that encoder for an
 262  * encoder's possible_clones field.
 263  */
 264 static inline u32 drm_encoder_mask(const struct drm_encoder *encoder)
 265 {
 266         return 1 << drm_encoder_index(encoder);
 267 }
 268
 269 /**
 270  * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
 271  * @encoder: encoder to test
 272  * @crtc: crtc to test
 273  *
 274  * Returns false if @encoder can't be driven by @crtc, true otherwise.
 275  */
 276 static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
 277                                        struct drm_crtc *crtc)
 278 {
 279         return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
 280 }
 281
 282 /**
 283  * drm_encoder_find - find a &drm_encoder
 284  * @dev: DRM device
 285  * @file_priv: drm file to check for lease against.
 286  * @id: encoder id
 287  *
 288  * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
 289  * drm_mode_object_find().
 290  */
 291 static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
 292                                                    struct drm_file *file_priv,
 293                                                    uint32_t id)
 294 {
 295         struct drm_mode_object *mo;
 296
 297         mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_ENCODER);
 298
 299         return mo ? obj_to_encoder(mo) : NULL;
 300 }
 301
 302 void drm_encoder_cleanup(struct drm_encoder *encoder);
 303
 304 /**
 305  * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
 306  * @encoder: the loop cursor
 307  * @dev: the DRM device
 308  * @encoder_mask: bitmask of encoder indices
 309  *
 310  * Iterate over all encoders specified by bitmask.
 311  */
 312 #define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
 313         list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
 314                 for_each_if ((encoder_mask) & drm_encoder_mask(encoder))
 315
 316 /**
 317  * drm_for_each_encoder - iterate over all encoders
 318  * @encoder: the loop cursor
 319  * @dev: the DRM device
 320  *
 321  * Iterate over all encoders of @dev.
 322  */
 323 #define drm_for_each_encoder(encoder, dev) \
 324         list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
 325
 326 #endif