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
  32 struct drm_encoder;
  33
  34 /**
  35  * struct drm_encoder_funcs - encoder controls
  36  *
  37  * Encoders sit between CRTCs and connectors.
  38  */
  39 struct drm_encoder_funcs {
  40         /**
  41          * @reset:
  42          *
  43          * Reset encoder hardware and software state to off. This function isn't
  44          * called by the core directly, only through drm_mode_config_reset().
  45          * It's not a helper hook only for historical reasons.
  46          */
  47         void (*reset)(struct drm_encoder *encoder);
  48
  49         /**
  50          * @destroy:
  51          *
  52          * Clean up encoder resources. This is only called at driver unload time
  53          * through drm_mode_config_cleanup() since an encoder cannot be
  54          * hotplugged in DRM.
  55          */
  56         void (*destroy)(struct drm_encoder *encoder);
  57
  58         /**
  59          * @late_register:
  60          *
  61          * This optional hook can be used to register additional userspace
  62          * interfaces attached to the encoder like debugfs interfaces.
  63          * It is called late in the driver load sequence from drm_dev_register().
  64          * Everything added from this callback should be unregistered in
  65          * the early_unregister callback.
  66          *
  67          * Returns:
  68          *
  69          * 0 on success, or a negative error code on failure.
  70          */
  71         int (*late_register)(struct drm_encoder *encoder);
  72
  73         /**
  74          * @early_unregister:
  75          *
  76          * This optional hook should be used to unregister the additional
  77          * userspace interfaces attached to the encoder from
  78          * @late_register. It is called from drm_dev_unregister(),
  79          * early in the driver unload sequence to disable userspace access
  80          * before data structures are torndown.
  81          */
  82         void (*early_unregister)(struct drm_encoder *encoder);
  83 };
  84
  85 /**
  86  * struct drm_encoder - central DRM encoder structure
  87  * @dev: parent DRM device
  88  * @head: list management
  89  * @base: base KMS object
  90  * @name: human readable name, can be overwritten by the driver
  91  * @bridge: bridge associated to the encoder
  92  * @funcs: control functions
  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_encoder_init().
 143          *
 144          * In reality almost every driver gets this wrong.
 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_encoder_init(). 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          * In reality almost every driver gets this wrong.
 162          *
 163          * Note that since encoder objects can't be hotplugged the assigned indices
 164          * are stable and hence known before registering all objects.
 165          */
 166         uint32_t possible_clones;
 167
 168         /**
 169          * @crtc: Currently bound CRTC, only really meaningful for non-atomic
 170          * drivers.  Atomic drivers should instead check
 171          * &drm_connector_state.crtc.
 172          */
 173         struct drm_crtc *crtc;
 174         struct drm_bridge *bridge;
 175         const struct drm_encoder_funcs *funcs;
 176         const struct drm_encoder_helper_funcs *helper_private;
 177 };
 178
 179 #define obj_to_encoder(x) container_of(x, struct drm_encoder, base)
 180
 181 __printf(5, 6)
 182 int drm_encoder_init(struct drm_device *dev,
 183                      struct drm_encoder *encoder,
 184                      const struct drm_encoder_funcs *funcs,
 185                      int encoder_type, const char *name, ...);
 186
 187 /**
 188  * drm_encoder_index - find the index of a registered encoder
 189  * @encoder: encoder to find index for
 190  *
 191  * Given a registered encoder, return the index of that encoder within a DRM
 192  * device's list of encoders.
 193  */
 194 static inline unsigned int drm_encoder_index(struct drm_encoder *encoder)
 195 {
 196         return encoder->index;
 197 }
 198
 199 /**
 200  * drm_encoder_crtc_ok - can a given crtc drive a given encoder?
 201  * @encoder: encoder to test
 202  * @crtc: crtc to test
 203  *
 204  * Returns false if @encoder can't be driven by @crtc, true otherwise.
 205  */
 206 static inline bool drm_encoder_crtc_ok(struct drm_encoder *encoder,
 207                                        struct drm_crtc *crtc)
 208 {
 209         return !!(encoder->possible_crtcs & drm_crtc_mask(crtc));
 210 }
 211
 212 /**
 213  * drm_encoder_find - find a &drm_encoder
 214  * @dev: DRM device
 215  * @file_priv: drm file to check for lease against.
 216  * @id: encoder id
 217  *
 218  * Returns the encoder with @id, NULL if it doesn't exist. Simple wrapper around
 219  * drm_mode_object_find().
 220  */
 221 static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
 222                                                    struct drm_file *file_priv,
 223                                                    uint32_t id)
 224 {
 225         struct drm_mode_object *mo;
 226
 227         mo = drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_ENCODER);
 228
 229         return mo ? obj_to_encoder(mo) : NULL;
 230 }
 231
 232 void drm_encoder_cleanup(struct drm_encoder *encoder);
 233
 234 /**
 235  * drm_for_each_encoder_mask - iterate over encoders specified by bitmask
 236  * @encoder: the loop cursor
 237  * @dev: the DRM device
 238  * @encoder_mask: bitmask of encoder indices
 239  *
 240  * Iterate over all encoders specified by bitmask.
 241  */
 242 #define drm_for_each_encoder_mask(encoder, dev, encoder_mask) \
 243         list_for_each_entry((encoder), &(dev)->mode_config.encoder_list, head) \
 244                 for_each_if ((encoder_mask) & (1 << drm_encoder_index(encoder)))
 245
 246 /**
 247  * drm_for_each_encoder - iterate over all encoders
 248  * @encoder: the loop cursor
 249  * @dev: the DRM device
 250  *
 251  * Iterate over all encoders of @dev.
 252  */
 253 #define drm_for_each_encoder(encoder, dev) \
 254         list_for_each_entry(encoder, &(dev)->mode_config.encoder_list, head)
 255
 256 #endif