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_mode_object.h>
  29
  30 /**
  31  * struct drm_encoder_funcs - encoder controls
  32  *
  33  * Encoders sit between CRTCs and connectors.
  34  */
  35 struct drm_encoder_funcs {
  36         /**
  37          * @reset:
  38          *
  39          * Reset encoder hardware and software state to off. This function isn't
  40          * called by the core directly, only through drm_mode_config_reset().
  41          * It's not a helper hook only for historical reasons.
  42          */
  43         void (*reset)(struct drm_encoder *encoder);
  44
  45         /**
  46          * @destroy:
  47          *
  48          * Clean up encoder resources. This is only called at driver unload time
  49          * through drm_mode_config_cleanup() since an encoder cannot be
  50          * hotplugged in DRM.
  51          */
  52         void (*destroy)(struct drm_encoder *encoder);
  53
  54         /**
  55          * @late_register:
  56          *
  57          * This optional hook can be used to register additional userspace
  58          * interfaces attached to the encoder like debugfs interfaces.
  59          * It is called late in the driver load sequence from drm_dev_register().
  60          * Everything added from this callback should be unregistered in
  61          * the early_unregister callback.
  62          *
  63          * Returns:
  64          *
  65          * 0 on success, or a negative error code on failure.
  66          */
  67         int (*late_register)(struct drm_encoder *encoder);
  68
  69         /**
  70          * @early_unregister:
  71          *
  72          * This optional hook should be used to unregister the additional
  73          * userspace interfaces attached to the encoder from
  74          * late_unregister(). It is called from drm_dev_unregister(),
  75          * early in the driver unload sequence to disable userspace access
  76          * before data structures are torndown.
  77          */
  78         void (*early_unregister)(struct drm_encoder *encoder);
  79 };
  80
  81 /**
  82  * struct drm_encoder - central DRM encoder structure
  83  * @dev: parent DRM device
  84  * @head: list management
  85  * @base: base KMS object
  86  * @name: human readable name, can be overwritten by the driver
  87  * @crtc: currently bound CRTC
  88  * @bridge: bridge associated to the encoder
  89  * @funcs: control functions
  90  * @helper_private: mid-layer private data
  91  *
  92  * CRTCs drive pixels to encoders, which convert them into signals
  93  * appropriate for a given connector or set of connectors.
  94  */
  95 struct drm_encoder {
  96         struct drm_device *dev;
  97         struct list_head head;
  98
  99         struct drm_mode_object base;
 100         char *name;
 101         /**
 102          * @encoder_type:
 103          *
 104          * One of the DRM_MODE_ENCODER_<foo> types in drm_mode.h. The following
 105          * encoder types are defined thus far:
 106          *
 107          * - DRM_MODE_ENCODER_DAC for VGA and analog on DVI-I/DVI-A.
 108          *
 109          * - DRM_MODE_ENCODER_TMDS for DVI, HDMI and (embedded) DisplayPort.
 110          *
 111          * - DRM_MODE_ENCODER_LVDS for display panels, or in general any panel
 112          *   with a proprietary parallel connector.
 113          *
 114          * - DRM_MODE_ENCODER_TVDAC for TV output (Composite, S-Video,
 115          *   Component, SCART).
 116          *
 117          * - DRM_MODE_ENCODER_VIRTUAL for virtual machine displays
 118          *
 119          * - DRM_MODE_ENCODER_DSI for panels connected using the DSI serial bus.
 120          *
 121          * - DRM_MODE_ENCODER_DPI for panels connected using the DPI parallel
 122          *   bus.
 123          *
 124          * - DRM_MODE_ENCODER_DPMST for special fake encoders used to allow
 125          *   mutliple DP MST streams to share one physical encoder.
 126          */
 127         int encoder_type;
 128
 129         /**
 130          * @index: Position inside the mode_config.list, can be used as an array
 131          * index. It is invariant over the lifetime of the encoder.
 132          */
 133         unsigned index;
 134
 135         /**
 136          * @possible_crtcs: Bitmask of potential CRTC bindings, using
 137          * drm_crtc_index() as the index into the bitfield. The driver must set
 138          * the bits for all &drm_crtc objects this encoder can be connected to
 139          * before calling drm_encoder_init().
 140          *
 141          * In reality almost every driver gets this wrong.
 142          *
 143          * Note that since CRTC objects can't be hotplugged the assigned indices
 144          * are stable and hence known before registering all objects.
 145          */
 146         uint32_t possible_crtcs;
 147
 148         /**
 149          * @possible_clones: Bitmask of potential sibling encoders for cloning,
 150          * using drm_encoder_index() as the index into the bitfield. The driver
 151          * must set the bits for all &drm_encoder objects which can clone a
 152          * &drm_crtc together with this encoder before calling
 153          * drm_encoder_init(). Drivers should set the bit representing the
 154          * encoder itself, too. Cloning bits should be set such that when two
 155          * encoders can be used in a cloned configuration, they both should have
 156          * each another bits set.
 157          *
 158          * In reality almost every driver gets this wrong.
 159          *
 160          * Note that since encoder objects can't be hotplugged the assigned indices
 161          * are stable and hence known before registering all objects.
 162          */
 163         uint32_t possible_clones;
 164
 165         struct drm_crtc *crtc;
 166         struct drm_bridge *bridge;
 167         const struct drm_encoder_funcs *funcs;
 168         const struct drm_encoder_helper_funcs *helper_private;
 169 };
 170
 171 #define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
 172
 173 __printf(5, 6)
 174 int drm_encoder_init(struct drm_device *dev,
 175                      struct drm_encoder *encoder,
 176                      const struct drm_encoder_funcs *funcs,
 177                      int encoder_type, const char *name, ...);
 178
 179 /**
 180  * drm_encoder_index - find the index of a registered encoder
 181  * @encoder: encoder to find index for
 182  *
 183  * Given a registered encoder, return the index of that encoder within a DRM
 184  * device's list of encoders.
 185  */
 186 static inline unsigned int drm_encoder_index(struct drm_encoder *encoder)
 187 {
 188         return encoder->index;
 189 }
 190
 191 /* FIXME: We have an include file mess still, drm_crtc.h needs untangling. */
 192 static inline uint32_t drm_crtc_mask(struct drm_crtc *crtc);
 193
 194 /**
 195  * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
 196  * @encoder: encoder to test
 197  * @crtc: crtc to test
 198  *
 199  * Returns false if @encoder can't be driven by @crtc, true otherwise.
 200  */
 201 static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
 202                                        struct drm_crtc *crtc)
 203 {
 204         return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
 205 }
 206
 207 /**
 208  * drm_encoder_find - find a &drm_encoder
 209  * @dev: DRM device
 210  * @id: encoder id
 211  *
 212  * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
 213  * drm_mode_object_find().
 214  */
 215 static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
 216                                                    uint32_t id)
 217 {
 218         struct drm_mode_object *mo;
 219
 220         mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_ENCODER);
 221
 222         return mo ? obj_to_encoder(mo) : NULL;
 223 }
 224
 225 void drm_encoder_cleanup(struct drm_encoder *encoder);
 226
 227 /**
 228  * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
 229  * @encoder: the loop cursor
 230  * @dev: the DRM device
 231  * @encoder_mask: bitmask of encoder indices
 232  *
 233  * Iterate over all encoders specified by bitmask.
 234  */
 235 #define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
 236         list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
 237                 for_each_if ((encoder_mask) & (1 << drm_encoder_index(encoder)))
 238
 239 /**
 240  * drm_for_each_encoder - iterate over all encoders
 241  * @encoder: the loop cursor
 242  * @dev: the DRM device
 243  *
 244  * Iterate over all encoders of @dev.
 245  */
 246 #define drm_for_each_encoder(encoder, dev) \
 247         list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
 248
 249 #endif