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  1. /*
  2.  * Copyright (c) 2006-2008 Intel Corporation
  3.  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
  4.  *
  5.  * DRM core CRTC related functions
  6.  *
  7.  * Permission to use, copy, modify, distribute, and sell this software and its
  8.  * documentation for any purpose is hereby granted without fee, provided that
  9.  * the above copyright notice appear in all copies and that both that copyright
  10.  * notice and this permission notice appear in supporting documentation, and
  11.  * that the name of the copyright holders not be used in advertising or
  12.  * publicity pertaining to distribution of the software without specific,
  13.  * written prior permission.  The copyright holders make no representations
  14.  * about the suitability of this software for any purpose.  It is provided "as
  15.  * is" without express or implied warranty.
  16.  *
  17.  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  18.  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  19.  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  20.  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  21.  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  22.  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  23.  * OF THIS SOFTWARE.
  24.  *
  25.  * Authors:
  26.  *      Keith Packard
  27.  *      Eric Anholt <eric@anholt.net>
  28.  *      Dave Airlie <airlied@linux.ie>
  29.  *      Jesse Barnes <jesse.barnes@intel.com>
  30.  */
  31.  
  32. #include <linux/kernel.h>
  33. #include <linux/export.h>
  34. #include <linux/moduleparam.h>
  35.  
  36. #include <drm/drmP.h>
  37. #include <drm/drm_atomic.h>
  38. #include <drm/drm_crtc.h>
  39. #include <drm/drm_fourcc.h>
  40. #include <drm/drm_crtc_helper.h>
  41. #include <drm/drm_fb_helper.h>
  42. #include <drm/drm_plane_helper.h>
  43. #include <drm/drm_atomic_helper.h>
  44. #include <drm/drm_edid.h>
  45.  
  46. /**
  47.  * DOC: overview
  48.  *
  49.  * The CRTC modeset helper library provides a default set_config implementation
  50.  * in drm_crtc_helper_set_config(). Plus a few other convenience functions using
  51.  * the same callbacks which drivers can use to e.g. restore the modeset
  52.  * configuration on resume with drm_helper_resume_force_mode().
  53.  *
  54.  * The driver callbacks are mostly compatible with the atomic modeset helpers,
  55.  * except for the handling of the primary plane: Atomic helpers require that the
  56.  * primary plane is implemented as a real standalone plane and not directly tied
  57.  * to the CRTC state. For easier transition this library provides functions to
  58.  * implement the old semantics required by the CRTC helpers using the new plane
  59.  * and atomic helper callbacks.
  60.  *
  61.  * Drivers are strongly urged to convert to the atomic helpers (by way of first
  62.  * converting to the plane helpers). New drivers must not use these functions
  63.  * but need to implement the atomic interface instead, potentially using the
  64.  * atomic helpers for that.
  65.  */
  66. MODULE_AUTHOR("David Airlie, Jesse Barnes");
  67. MODULE_DESCRIPTION("DRM KMS helper");
  68. MODULE_LICENSE("GPL and additional rights");
  69.  
  70. /**
  71.  * drm_helper_move_panel_connectors_to_head() - move panels to the front in the
  72.  *                                              connector list
  73.  * @dev: drm device to operate on
  74.  *
  75.  * Some userspace presumes that the first connected connector is the main
  76.  * display, where it's supposed to display e.g. the login screen. For
  77.  * laptops, this should be the main panel. Use this function to sort all
  78.  * (eDP/LVDS) panels to the front of the connector list, instead of
  79.  * painstakingly trying to initialize them in the right order.
  80.  */
  81. void drm_helper_move_panel_connectors_to_head(struct drm_device *dev)
  82. {
  83.         struct drm_connector *connector, *tmp;
  84.         struct list_head panel_list;
  85.  
  86.         INIT_LIST_HEAD(&panel_list);
  87.  
  88.         list_for_each_entry_safe(connector, tmp,
  89.                                  &dev->mode_config.connector_list, head) {
  90.                 if (connector->connector_type == DRM_MODE_CONNECTOR_LVDS ||
  91.                     connector->connector_type == DRM_MODE_CONNECTOR_eDP)
  92.                         list_move_tail(&connector->head, &panel_list);
  93.         }
  94.  
  95.         list_splice(&panel_list, &dev->mode_config.connector_list);
  96. }
  97. EXPORT_SYMBOL(drm_helper_move_panel_connectors_to_head);
  98.  
  99. /**
  100.  * drm_helper_encoder_in_use - check if a given encoder is in use
  101.  * @encoder: encoder to check
  102.  *
  103.  * Checks whether @encoder is with the current mode setting output configuration
  104.  * in use by any connector. This doesn't mean that it is actually enabled since
  105.  * the DPMS state is tracked separately.
  106.  *
  107.  * Returns:
  108.  * True if @encoder is used, false otherwise.
  109.  */
  110. bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
  111. {
  112.         struct drm_connector *connector;
  113.         struct drm_device *dev = encoder->dev;
  114.  
  115.         /*
  116.          * We can expect this mutex to be locked if we are not panicking.
  117.          * Locking is currently fubar in the panic handler.
  118.          */
  119.         if (!oops_in_progress) {
  120.                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
  121.                 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
  122.         }
  123.  
  124.         drm_for_each_connector(connector, dev)
  125.                 if (connector->encoder == encoder)
  126.                         return true;
  127.         return false;
  128. }
  129. EXPORT_SYMBOL(drm_helper_encoder_in_use);
  130.  
  131. /**
  132.  * drm_helper_crtc_in_use - check if a given CRTC is in a mode_config
  133.  * @crtc: CRTC to check
  134.  *
  135.  * Checks whether @crtc is with the current mode setting output configuration
  136.  * in use by any connector. This doesn't mean that it is actually enabled since
  137.  * the DPMS state is tracked separately.
  138.  *
  139.  * Returns:
  140.  * True if @crtc is used, false otherwise.
  141.  */
  142. bool drm_helper_crtc_in_use(struct drm_crtc *crtc)
  143. {
  144.         struct drm_encoder *encoder;
  145.         struct drm_device *dev = crtc->dev;
  146.  
  147.         /*
  148.          * We can expect this mutex to be locked if we are not panicking.
  149.          * Locking is currently fubar in the panic handler.
  150.          */
  151.         if (!oops_in_progress)
  152.                 WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
  153.  
  154.         drm_for_each_encoder(encoder, dev)
  155.                 if (encoder->crtc == crtc && drm_helper_encoder_in_use(encoder))
  156.                         return true;
  157.         return false;
  158. }
  159. EXPORT_SYMBOL(drm_helper_crtc_in_use);
  160.  
  161. static void
  162. drm_encoder_disable(struct drm_encoder *encoder)
  163. {
  164.         const struct drm_encoder_helper_funcs *encoder_funcs = encoder->helper_private;
  165.  
  166.         drm_bridge_disable(encoder->bridge);
  167.  
  168.         if (encoder_funcs->disable)
  169.                 (*encoder_funcs->disable)(encoder);
  170.         else
  171.                 (*encoder_funcs->dpms)(encoder, DRM_MODE_DPMS_OFF);
  172.  
  173.         drm_bridge_post_disable(encoder->bridge);
  174. }
  175.  
  176. static void __drm_helper_disable_unused_functions(struct drm_device *dev)
  177. {
  178.         struct drm_encoder *encoder;
  179.         struct drm_crtc *crtc;
  180.  
  181.         drm_warn_on_modeset_not_all_locked(dev);
  182.  
  183.         drm_for_each_encoder(encoder, dev) {
  184.                 if (!drm_helper_encoder_in_use(encoder)) {
  185.                         drm_encoder_disable(encoder);
  186.                         /* disconnect encoder from any connector */
  187.                         encoder->crtc = NULL;
  188.                 }
  189.         }
  190.  
  191.         drm_for_each_crtc(crtc, dev) {
  192.                 const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
  193.                 crtc->enabled = drm_helper_crtc_in_use(crtc);
  194.                 if (!crtc->enabled) {
  195.                         if (crtc_funcs->disable)
  196.                                 (*crtc_funcs->disable)(crtc);
  197.                         else
  198.                                 (*crtc_funcs->dpms)(crtc, DRM_MODE_DPMS_OFF);
  199.                         crtc->primary->fb = NULL;
  200.                 }
  201.         }
  202. }
  203.  
  204. /**
  205.  * drm_helper_disable_unused_functions - disable unused objects
  206.  * @dev: DRM device
  207.  *
  208.  * This function walks through the entire mode setting configuration of @dev. It
  209.  * will remove any crtc links of unused encoders and encoder links of
  210.  * disconnected connectors. Then it will disable all unused encoders and crtcs
  211.  * either by calling their disable callback if available or by calling their
  212.  * dpms callback with DRM_MODE_DPMS_OFF.
  213.  */
  214. void drm_helper_disable_unused_functions(struct drm_device *dev)
  215. {
  216.         drm_modeset_lock_all(dev);
  217.         __drm_helper_disable_unused_functions(dev);
  218.         drm_modeset_unlock_all(dev);
  219. }
  220. EXPORT_SYMBOL(drm_helper_disable_unused_functions);
  221.  
  222. /*
  223.  * Check the CRTC we're going to map each output to vs. its current
  224.  * CRTC.  If they don't match, we have to disable the output and the CRTC
  225.  * since the driver will have to re-route things.
  226.  */
  227. static void
  228. drm_crtc_prepare_encoders(struct drm_device *dev)
  229. {
  230.         const struct drm_encoder_helper_funcs *encoder_funcs;
  231.         struct drm_encoder *encoder;
  232.  
  233.         drm_for_each_encoder(encoder, dev) {
  234.                 encoder_funcs = encoder->helper_private;
  235.                 /* Disable unused encoders */
  236.                 if (encoder->crtc == NULL)
  237.                         drm_encoder_disable(encoder);
  238.                 /* Disable encoders whose CRTC is about to change */
  239.                 if (encoder_funcs->get_crtc &&
  240.                     encoder->crtc != (*encoder_funcs->get_crtc)(encoder))
  241.                         drm_encoder_disable(encoder);
  242.         }
  243. }
  244.  
  245. /**
  246.  * drm_crtc_helper_set_mode - internal helper to set a mode
  247.  * @crtc: CRTC to program
  248.  * @mode: mode to use
  249.  * @x: horizontal offset into the surface
  250.  * @y: vertical offset into the surface
  251.  * @old_fb: old framebuffer, for cleanup
  252.  *
  253.  * Try to set @mode on @crtc.  Give @crtc and its associated connectors a chance
  254.  * to fixup or reject the mode prior to trying to set it. This is an internal
  255.  * helper that drivers could e.g. use to update properties that require the
  256.  * entire output pipe to be disabled and re-enabled in a new configuration. For
  257.  * example for changing whether audio is enabled on a hdmi link or for changing
  258.  * panel fitter or dither attributes. It is also called by the
  259.  * drm_crtc_helper_set_config() helper function to drive the mode setting
  260.  * sequence.
  261.  *
  262.  * Returns:
  263.  * True if the mode was set successfully, false otherwise.
  264.  */
  265. bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
  266.                               struct drm_display_mode *mode,
  267.                               int x, int y,
  268.                               struct drm_framebuffer *old_fb)
  269. {
  270.         struct drm_device *dev = crtc->dev;
  271.         struct drm_display_mode *adjusted_mode, saved_mode, saved_hwmode;
  272.         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
  273.         const struct drm_encoder_helper_funcs *encoder_funcs;
  274.         int saved_x, saved_y;
  275.         bool saved_enabled;
  276.         struct drm_encoder *encoder;
  277.         bool ret = true;
  278.  
  279.         drm_warn_on_modeset_not_all_locked(dev);
  280.  
  281.         saved_enabled = crtc->enabled;
  282.         crtc->enabled = drm_helper_crtc_in_use(crtc);
  283.         if (!crtc->enabled)
  284.                 return true;
  285.  
  286.         adjusted_mode = drm_mode_duplicate(dev, mode);
  287.         if (!adjusted_mode) {
  288.                 crtc->enabled = saved_enabled;
  289.                 return false;
  290.         }
  291.  
  292.         saved_mode = crtc->mode;
  293.         saved_hwmode = crtc->hwmode;
  294.         saved_x = crtc->x;
  295.         saved_y = crtc->y;
  296.  
  297.         /* Update crtc values up front so the driver can rely on them for mode
  298.          * setting.
  299.          */
  300.         crtc->mode = *mode;
  301.         crtc->x = x;
  302.         crtc->y = y;
  303.  
  304.         /* Pass our mode to the connectors and the CRTC to give them a chance to
  305.          * adjust it according to limitations or connector properties, and also
  306.          * a chance to reject the mode entirely.
  307.          */
  308.         drm_for_each_encoder(encoder, dev) {
  309.  
  310.                 if (encoder->crtc != crtc)
  311.                         continue;
  312.  
  313.                 ret = drm_bridge_mode_fixup(encoder->bridge,
  314.                         mode, adjusted_mode);
  315.                 if (!ret) {
  316.                         DRM_DEBUG_KMS("Bridge fixup failed\n");
  317.                         goto done;
  318.                 }
  319.  
  320.                 encoder_funcs = encoder->helper_private;
  321.                 if (!(ret = encoder_funcs->mode_fixup(encoder, mode,
  322.                                                       adjusted_mode))) {
  323.                         DRM_DEBUG_KMS("Encoder fixup failed\n");
  324.                         goto done;
  325.                 }
  326.         }
  327.  
  328.         if (!(ret = crtc_funcs->mode_fixup(crtc, mode, adjusted_mode))) {
  329.                 DRM_DEBUG_KMS("CRTC fixup failed\n");
  330.                 goto done;
  331.         }
  332.         DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
  333.  
  334.         crtc->hwmode = *adjusted_mode;
  335.  
  336.         /* Prepare the encoders and CRTCs before setting the mode. */
  337.         drm_for_each_encoder(encoder, dev) {
  338.  
  339.                 if (encoder->crtc != crtc)
  340.                         continue;
  341.  
  342.                 drm_bridge_disable(encoder->bridge);
  343.  
  344.                 encoder_funcs = encoder->helper_private;
  345.                 /* Disable the encoders as the first thing we do. */
  346.                 encoder_funcs->prepare(encoder);
  347.  
  348.                 drm_bridge_post_disable(encoder->bridge);
  349.         }
  350.  
  351.         drm_crtc_prepare_encoders(dev);
  352.  
  353.         crtc_funcs->prepare(crtc);
  354.  
  355.         /* Set up the DPLL and any encoders state that needs to adjust or depend
  356.          * on the DPLL.
  357.          */
  358.         ret = !crtc_funcs->mode_set(crtc, mode, adjusted_mode, x, y, old_fb);
  359.         if (!ret)
  360.             goto done;
  361.  
  362.         drm_for_each_encoder(encoder, dev) {
  363.  
  364.                 if (encoder->crtc != crtc)
  365.                         continue;
  366.  
  367.                 DRM_DEBUG_KMS("[ENCODER:%d:%s] set [MODE:%d:%s]\n",
  368.                         encoder->base.id, encoder->name,
  369.                         mode->base.id, mode->name);
  370.                 encoder_funcs = encoder->helper_private;
  371.                 encoder_funcs->mode_set(encoder, mode, adjusted_mode);
  372.  
  373.                 drm_bridge_mode_set(encoder->bridge, mode, adjusted_mode);
  374.         }
  375.  
  376.         /* Now enable the clocks, plane, pipe, and connectors that we set up. */
  377.         crtc_funcs->commit(crtc);
  378.  
  379.         drm_for_each_encoder(encoder, dev) {
  380.  
  381.                 if (encoder->crtc != crtc)
  382.                         continue;
  383.  
  384.                 drm_bridge_pre_enable(encoder->bridge);
  385.  
  386.                 encoder_funcs = encoder->helper_private;
  387.                 encoder_funcs->commit(encoder);
  388.  
  389.                 drm_bridge_enable(encoder->bridge);
  390.         }
  391.  
  392.         /* Calculate and store various constants which
  393.          * are later needed by vblank and swap-completion
  394.          * timestamping. They are derived from true hwmode.
  395.          */
  396.         drm_calc_timestamping_constants(crtc, &crtc->hwmode);
  397.  
  398.         /* FIXME: add subpixel order */
  399. done:
  400.         drm_mode_destroy(dev, adjusted_mode);
  401.         if (!ret) {
  402.                 crtc->enabled = saved_enabled;
  403.                 crtc->mode = saved_mode;
  404.                 crtc->hwmode = saved_hwmode;
  405.                 crtc->x = saved_x;
  406.                 crtc->y = saved_y;
  407.         }
  408.  
  409.         return ret;
  410. }
  411. EXPORT_SYMBOL(drm_crtc_helper_set_mode);
  412.  
  413. static void
  414. drm_crtc_helper_disable(struct drm_crtc *crtc)
  415. {
  416.         struct drm_device *dev = crtc->dev;
  417.         struct drm_connector *connector;
  418.         struct drm_encoder *encoder;
  419.  
  420.         /* Decouple all encoders and their attached connectors from this crtc */
  421.         drm_for_each_encoder(encoder, dev) {
  422.                 if (encoder->crtc != crtc)
  423.                         continue;
  424.  
  425.                 drm_for_each_connector(connector, dev) {
  426.                         if (connector->encoder != encoder)
  427.                                 continue;
  428.  
  429.                         connector->encoder = NULL;
  430.  
  431.                         /*
  432.                          * drm_helper_disable_unused_functions() ought to be
  433.                          * doing this, but since we've decoupled the encoder
  434.                          * from the connector above, the required connection
  435.                          * between them is henceforth no longer available.
  436.                          */
  437.                         connector->dpms = DRM_MODE_DPMS_OFF;
  438.                 }
  439.         }
  440.  
  441.         __drm_helper_disable_unused_functions(dev);
  442. }
  443.  
  444. /**
  445.  * drm_crtc_helper_set_config - set a new config from userspace
  446.  * @set: mode set configuration
  447.  *
  448.  * Setup a new configuration, provided by the upper layers (either an ioctl call
  449.  * from userspace or internally e.g. from the fbdev support code) in @set, and
  450.  * enable it. This is the main helper functions for drivers that implement
  451.  * kernel mode setting with the crtc helper functions and the assorted
  452.  * ->prepare(), ->modeset() and ->commit() helper callbacks.
  453.  *
  454.  * Returns:
  455.  * Returns 0 on success, negative errno numbers on failure.
  456.  */
  457. int drm_crtc_helper_set_config(struct drm_mode_set *set)
  458. {
  459.         struct drm_device *dev;
  460.         struct drm_crtc *new_crtc;
  461.         struct drm_encoder *save_encoders, *new_encoder, *encoder;
  462.         bool mode_changed = false; /* if true do a full mode set */
  463.         bool fb_changed = false; /* if true and !mode_changed just do a flip */
  464.         struct drm_connector *save_connectors, *connector;
  465.         int count = 0, ro, fail = 0;
  466.         const struct drm_crtc_helper_funcs *crtc_funcs;
  467.         struct drm_mode_set save_set;
  468.         int ret;
  469.         int i;
  470.  
  471.         DRM_DEBUG_KMS("\n");
  472.  
  473.         BUG_ON(!set);
  474.         BUG_ON(!set->crtc);
  475.         BUG_ON(!set->crtc->helper_private);
  476.  
  477.         /* Enforce sane interface api - has been abused by the fb helper. */
  478.         BUG_ON(!set->mode && set->fb);
  479.         BUG_ON(set->fb && set->num_connectors == 0);
  480.  
  481.         crtc_funcs = set->crtc->helper_private;
  482.  
  483.         if (!set->mode)
  484.                 set->fb = NULL;
  485.  
  486.         if (set->fb) {
  487.                 DRM_DEBUG_KMS("[CRTC:%d] [FB:%d] #connectors=%d (x y) (%i %i)\n",
  488.                                 set->crtc->base.id, set->fb->base.id,
  489.                                 (int)set->num_connectors, set->x, set->y);
  490.         } else {
  491.                 DRM_DEBUG_KMS("[CRTC:%d] [NOFB]\n", set->crtc->base.id);
  492.                 drm_crtc_helper_disable(set->crtc);
  493.                 return 0;
  494.         }
  495.  
  496.         dev = set->crtc->dev;
  497.  
  498.         drm_warn_on_modeset_not_all_locked(dev);
  499.  
  500.         /*
  501.          * Allocate space for the backup of all (non-pointer) encoder and
  502.          * connector data.
  503.          */
  504.         save_encoders = kzalloc(dev->mode_config.num_encoder *
  505.                                 sizeof(struct drm_encoder), GFP_KERNEL);
  506.         if (!save_encoders)
  507.                 return -ENOMEM;
  508.  
  509.         save_connectors = kzalloc(dev->mode_config.num_connector *
  510.                                 sizeof(struct drm_connector), GFP_KERNEL);
  511.         if (!save_connectors) {
  512.                 kfree(save_encoders);
  513.                 return -ENOMEM;
  514.         }
  515.  
  516.         /*
  517.          * Copy data. Note that driver private data is not affected.
  518.          * Should anything bad happen only the expected state is
  519.          * restored, not the drivers personal bookkeeping.
  520.          */
  521.         count = 0;
  522.         drm_for_each_encoder(encoder, dev) {
  523.                 save_encoders[count++] = *encoder;
  524.         }
  525.  
  526.         count = 0;
  527.         drm_for_each_connector(connector, dev) {
  528.                 save_connectors[count++] = *connector;
  529.         }
  530.  
  531.         save_set.crtc = set->crtc;
  532.         save_set.mode = &set->crtc->mode;
  533.         save_set.x = set->crtc->x;
  534.         save_set.y = set->crtc->y;
  535.         save_set.fb = set->crtc->primary->fb;
  536.  
  537.         /* We should be able to check here if the fb has the same properties
  538.          * and then just flip_or_move it */
  539.         if (set->crtc->primary->fb != set->fb) {
  540.                 /* If we have no fb then treat it as a full mode set */
  541.                 if (set->crtc->primary->fb == NULL) {
  542.                         DRM_DEBUG_KMS("crtc has no fb, full mode set\n");
  543.                         mode_changed = true;
  544.                 } else if (set->fb == NULL) {
  545.                         mode_changed = true;
  546.                 } else if (set->fb->pixel_format !=
  547.                            set->crtc->primary->fb->pixel_format) {
  548.                         mode_changed = true;
  549.                 } else
  550.                         fb_changed = true;
  551.         }
  552.  
  553.         if (set->x != set->crtc->x || set->y != set->crtc->y)
  554.                 fb_changed = true;
  555.  
  556.         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
  557.                 DRM_DEBUG_KMS("modes are different, full mode set\n");
  558.                 drm_mode_debug_printmodeline(&set->crtc->mode);
  559.                 drm_mode_debug_printmodeline(set->mode);
  560.                 mode_changed = true;
  561.         }
  562.  
  563.         /* a) traverse passed in connector list and get encoders for them */
  564.         count = 0;
  565.         drm_for_each_connector(connector, dev) {
  566.                 const struct drm_connector_helper_funcs *connector_funcs =
  567.                         connector->helper_private;
  568.                 new_encoder = connector->encoder;
  569.                 for (ro = 0; ro < set->num_connectors; ro++) {
  570.                         if (set->connectors[ro] == connector) {
  571.                                 new_encoder = connector_funcs->best_encoder(connector);
  572.                                 /* if we can't get an encoder for a connector
  573.                                    we are setting now - then fail */
  574.                                 if (new_encoder == NULL)
  575.                                         /* don't break so fail path works correct */
  576.                                         fail = 1;
  577.  
  578.                                 if (connector->dpms != DRM_MODE_DPMS_ON) {
  579.                                         DRM_DEBUG_KMS("connector dpms not on, full mode switch\n");
  580.                                         mode_changed = true;
  581.                                 }
  582.  
  583.                                 break;
  584.                         }
  585.                 }
  586.  
  587.                 if (new_encoder != connector->encoder) {
  588.                         DRM_DEBUG_KMS("encoder changed, full mode switch\n");
  589.                         mode_changed = true;
  590.                         /* If the encoder is reused for another connector, then
  591.                          * the appropriate crtc will be set later.
  592.                          */
  593.                         if (connector->encoder)
  594.                                 connector->encoder->crtc = NULL;
  595.                         connector->encoder = new_encoder;
  596.                 }
  597.         }
  598.  
  599.         if (fail) {
  600.                 ret = -EINVAL;
  601.                 goto fail;
  602.         }
  603.  
  604.         count = 0;
  605.         drm_for_each_connector(connector, dev) {
  606.                 if (!connector->encoder)
  607.                         continue;
  608.  
  609.                 if (connector->encoder->crtc == set->crtc)
  610.                         new_crtc = NULL;
  611.                 else
  612.                         new_crtc = connector->encoder->crtc;
  613.  
  614.                 for (ro = 0; ro < set->num_connectors; ro++) {
  615.                         if (set->connectors[ro] == connector)
  616.                                 new_crtc = set->crtc;
  617.                 }
  618.  
  619.                 /* Make sure the new CRTC will work with the encoder */
  620.                 if (new_crtc &&
  621.                     !drm_encoder_crtc_ok(connector->encoder, new_crtc)) {
  622.                         ret = -EINVAL;
  623.                         goto fail;
  624.                 }
  625.                 if (new_crtc != connector->encoder->crtc) {
  626.                         DRM_DEBUG_KMS("crtc changed, full mode switch\n");
  627.                         mode_changed = true;
  628.                         connector->encoder->crtc = new_crtc;
  629.                 }
  630.                 if (new_crtc) {
  631.                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [CRTC:%d]\n",
  632.                                 connector->base.id, connector->name,
  633.                                 new_crtc->base.id);
  634.                 } else {
  635.                         DRM_DEBUG_KMS("[CONNECTOR:%d:%s] to [NOCRTC]\n",
  636.                                 connector->base.id, connector->name);
  637.                 }
  638.         }
  639.  
  640.         /* mode_set_base is not a required function */
  641.         if (fb_changed && !crtc_funcs->mode_set_base)
  642.                 mode_changed = true;
  643.  
  644.         if (mode_changed) {
  645.                 if (drm_helper_crtc_in_use(set->crtc)) {
  646.                         DRM_DEBUG_KMS("attempting to set mode from"
  647.                                         " userspace\n");
  648.                         drm_mode_debug_printmodeline(set->mode);
  649.                         set->crtc->primary->fb = set->fb;
  650.                         if (!drm_crtc_helper_set_mode(set->crtc, set->mode,
  651.                                                       set->x, set->y,
  652.                                                       save_set.fb)) {
  653.                                 DRM_ERROR("failed to set mode on [CRTC:%d]\n",
  654.                                           set->crtc->base.id);
  655.                                 set->crtc->primary->fb = save_set.fb;
  656.                                 ret = -EINVAL;
  657.                                 goto fail;
  658.                         }
  659.                         DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
  660.                         for (i = 0; i < set->num_connectors; i++) {
  661.                                 DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
  662.                                               set->connectors[i]->name);
  663.                                 set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
  664.                         }
  665.                 }
  666.                 __drm_helper_disable_unused_functions(dev);
  667.         } else if (fb_changed) {
  668.                 set->crtc->x = set->x;
  669.                 set->crtc->y = set->y;
  670.                 set->crtc->primary->fb = set->fb;
  671.                 ret = crtc_funcs->mode_set_base(set->crtc,
  672.                                                 set->x, set->y, save_set.fb);
  673.                 if (ret != 0) {
  674.                         set->crtc->x = save_set.x;
  675.                         set->crtc->y = save_set.y;
  676.                         set->crtc->primary->fb = save_set.fb;
  677.                         goto fail;
  678.                 }
  679.         }
  680.  
  681.         kfree(save_connectors);
  682.         kfree(save_encoders);
  683.         return 0;
  684.  
  685. fail:
  686.         /* Restore all previous data. */
  687.         count = 0;
  688.         drm_for_each_encoder(encoder, dev) {
  689.                 *encoder = save_encoders[count++];
  690.         }
  691.  
  692.         count = 0;
  693.         drm_for_each_connector(connector, dev) {
  694.                 *connector = save_connectors[count++];
  695.         }
  696.  
  697.         /* Try to restore the config */
  698.         if (mode_changed &&
  699.             !drm_crtc_helper_set_mode(save_set.crtc, save_set.mode, save_set.x,
  700.                                       save_set.y, save_set.fb))
  701.                 DRM_ERROR("failed to restore config after modeset failure\n");
  702.  
  703.         kfree(save_connectors);
  704.         kfree(save_encoders);
  705.         return ret;
  706. }
  707. EXPORT_SYMBOL(drm_crtc_helper_set_config);
  708.  
  709. static int drm_helper_choose_encoder_dpms(struct drm_encoder *encoder)
  710. {
  711.         int dpms = DRM_MODE_DPMS_OFF;
  712.         struct drm_connector *connector;
  713.         struct drm_device *dev = encoder->dev;
  714.  
  715.         drm_for_each_connector(connector, dev)
  716.                 if (connector->encoder == encoder)
  717.                         if (connector->dpms < dpms)
  718.                                 dpms = connector->dpms;
  719.         return dpms;
  720. }
  721.  
  722. /* Helper which handles bridge ordering around encoder dpms */
  723. static void drm_helper_encoder_dpms(struct drm_encoder *encoder, int mode)
  724. {
  725.         struct drm_bridge *bridge = encoder->bridge;
  726.         const struct drm_encoder_helper_funcs *encoder_funcs;
  727.  
  728.         if (mode == DRM_MODE_DPMS_ON)
  729.                 drm_bridge_pre_enable(bridge);
  730.         else
  731.                 drm_bridge_disable(bridge);
  732.  
  733.         encoder_funcs = encoder->helper_private;
  734.         if (encoder_funcs->dpms)
  735.                 encoder_funcs->dpms(encoder, mode);
  736.  
  737.         if (mode == DRM_MODE_DPMS_ON)
  738.                 drm_bridge_enable(bridge);
  739.         else
  740.                 drm_bridge_post_disable(bridge);
  741. }
  742.  
  743. static int drm_helper_choose_crtc_dpms(struct drm_crtc *crtc)
  744. {
  745.         int dpms = DRM_MODE_DPMS_OFF;
  746.         struct drm_connector *connector;
  747.         struct drm_device *dev = crtc->dev;
  748.  
  749.         drm_for_each_connector(connector, dev)
  750.                 if (connector->encoder && connector->encoder->crtc == crtc)
  751.                         if (connector->dpms < dpms)
  752.                                 dpms = connector->dpms;
  753.         return dpms;
  754. }
  755.  
  756. /**
  757.  * drm_helper_connector_dpms() - connector dpms helper implementation
  758.  * @connector: affected connector
  759.  * @mode: DPMS mode
  760.  *
  761.  * This is the main helper function provided by the crtc helper framework for
  762.  * implementing the DPMS connector attribute. It computes the new desired DPMS
  763.  * state for all encoders and crtcs in the output mesh and calls the ->dpms()
  764.  * callback provided by the driver appropriately.
  765.  *
  766.  * Returns:
  767.  * Always returns 0.
  768.  */
  769. int drm_helper_connector_dpms(struct drm_connector *connector, int mode)
  770. {
  771.         struct drm_encoder *encoder = connector->encoder;
  772.         struct drm_crtc *crtc = encoder ? encoder->crtc : NULL;
  773.         int old_dpms, encoder_dpms = DRM_MODE_DPMS_OFF;
  774.  
  775.         if (mode == connector->dpms)
  776.                 return 0;
  777.  
  778.         old_dpms = connector->dpms;
  779.         connector->dpms = mode;
  780.  
  781.         if (encoder)
  782.                 encoder_dpms = drm_helper_choose_encoder_dpms(encoder);
  783.  
  784.         /* from off to on, do crtc then encoder */
  785.         if (mode < old_dpms) {
  786.                 if (crtc) {
  787.                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
  788.                         if (crtc_funcs->dpms)
  789.                                 (*crtc_funcs->dpms) (crtc,
  790.                                                      drm_helper_choose_crtc_dpms(crtc));
  791.                 }
  792.                 if (encoder)
  793.                         drm_helper_encoder_dpms(encoder, encoder_dpms);
  794.         }
  795.  
  796.         /* from on to off, do encoder then crtc */
  797.         if (mode > old_dpms) {
  798.                 if (encoder)
  799.                         drm_helper_encoder_dpms(encoder, encoder_dpms);
  800.                 if (crtc) {
  801.                         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
  802.                         if (crtc_funcs->dpms)
  803.                                 (*crtc_funcs->dpms) (crtc,
  804.                                                      drm_helper_choose_crtc_dpms(crtc));
  805.                 }
  806.         }
  807.  
  808.         return 0;
  809. }
  810. EXPORT_SYMBOL(drm_helper_connector_dpms);
  811.  
  812. /**
  813.  * drm_helper_mode_fill_fb_struct - fill out framebuffer metadata
  814.  * @fb: drm_framebuffer object to fill out
  815.  * @mode_cmd: metadata from the userspace fb creation request
  816.  *
  817.  * This helper can be used in a drivers fb_create callback to pre-fill the fb's
  818.  * metadata fields.
  819.  */
  820. void drm_helper_mode_fill_fb_struct(struct drm_framebuffer *fb,
  821.                                     struct drm_mode_fb_cmd2 *mode_cmd)
  822. {
  823.         int i;
  824.  
  825.         fb->width = mode_cmd->width;
  826.         fb->height = mode_cmd->height;
  827.         for (i = 0; i < 4; i++) {
  828.                 fb->pitches[i] = mode_cmd->pitches[i];
  829.                 fb->offsets[i] = mode_cmd->offsets[i];
  830.                 fb->modifier[i] = mode_cmd->modifier[i];
  831.         }
  832.         drm_fb_get_bpp_depth(mode_cmd->pixel_format, &fb->depth,
  833.                                     &fb->bits_per_pixel);
  834.         fb->pixel_format = mode_cmd->pixel_format;
  835.         fb->flags = mode_cmd->flags;
  836. }
  837. EXPORT_SYMBOL(drm_helper_mode_fill_fb_struct);
  838.  
  839. /**
  840.  * drm_helper_resume_force_mode - force-restore mode setting configuration
  841.  * @dev: drm_device which should be restored
  842.  *
  843.  * Drivers which use the mode setting helpers can use this function to
  844.  * force-restore the mode setting configuration e.g. on resume or when something
  845.  * else might have trampled over the hw state (like some overzealous old BIOSen
  846.  * tended to do).
  847.  *
  848.  * This helper doesn't provide a error return value since restoring the old
  849.  * config should never fail due to resource allocation issues since the driver
  850.  * has successfully set the restored configuration already. Hence this should
  851.  * boil down to the equivalent of a few dpms on calls, which also don't provide
  852.  * an error code.
  853.  *
  854.  * Drivers where simply restoring an old configuration again might fail (e.g.
  855.  * due to slight differences in allocating shared resources when the
  856.  * configuration is restored in a different order than when userspace set it up)
  857.  * need to use their own restore logic.
  858.  */
  859. void drm_helper_resume_force_mode(struct drm_device *dev)
  860. {
  861.         struct drm_crtc *crtc;
  862.         struct drm_encoder *encoder;
  863.         const struct drm_crtc_helper_funcs *crtc_funcs;
  864.         int encoder_dpms;
  865.         bool ret;
  866.  
  867.         drm_modeset_lock_all(dev);
  868.         drm_for_each_crtc(crtc, dev) {
  869.  
  870.                 if (!crtc->enabled)
  871.                         continue;
  872.  
  873.                 ret = drm_crtc_helper_set_mode(crtc, &crtc->mode,
  874.                                                crtc->x, crtc->y, crtc->primary->fb);
  875.  
  876.                 /* Restoring the old config should never fail! */
  877.                 if (ret == false)
  878.                         DRM_ERROR("failed to set mode on crtc %p\n", crtc);
  879.  
  880.                 /* Turn off outputs that were already powered off */
  881.                 if (drm_helper_choose_crtc_dpms(crtc)) {
  882.                         drm_for_each_encoder(encoder, dev) {
  883.  
  884.                                 if(encoder->crtc != crtc)
  885.                                         continue;
  886.  
  887.                                 encoder_dpms = drm_helper_choose_encoder_dpms(
  888.                                                         encoder);
  889.  
  890.                                 drm_helper_encoder_dpms(encoder, encoder_dpms);
  891.                         }
  892.  
  893.                         crtc_funcs = crtc->helper_private;
  894.                         if (crtc_funcs->dpms)
  895.                                 (*crtc_funcs->dpms) (crtc,
  896.                                                      drm_helper_choose_crtc_dpms(crtc));
  897.                 }
  898.         }
  899.  
  900.         /* disable the unused connectors while restoring the modesetting */
  901.         __drm_helper_disable_unused_functions(dev);
  902.         drm_modeset_unlock_all(dev);
  903. }
  904. EXPORT_SYMBOL(drm_helper_resume_force_mode);
  905.  
  906. /**
  907.  * drm_helper_crtc_mode_set - mode_set implementation for atomic plane helpers
  908.  * @crtc: DRM CRTC
  909.  * @mode: DRM display mode which userspace requested
  910.  * @adjusted_mode: DRM display mode adjusted by ->mode_fixup callbacks
  911.  * @x: x offset of the CRTC scanout area on the underlying framebuffer
  912.  * @y: y offset of the CRTC scanout area on the underlying framebuffer
  913.  * @old_fb: previous framebuffer
  914.  *
  915.  * This function implements a callback useable as the ->mode_set callback
  916.  * required by the crtc helpers. Besides the atomic plane helper functions for
  917.  * the primary plane the driver must also provide the ->mode_set_nofb callback
  918.  * to set up the crtc.
  919.  *
  920.  * This is a transitional helper useful for converting drivers to the atomic
  921.  * interfaces.
  922.  */
  923. int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mode,
  924.                              struct drm_display_mode *adjusted_mode, int x, int y,
  925.                              struct drm_framebuffer *old_fb)
  926. {
  927.         struct drm_crtc_state *crtc_state;
  928.         const struct drm_crtc_helper_funcs *crtc_funcs = crtc->helper_private;
  929.         int ret;
  930.  
  931.         if (crtc->funcs->atomic_duplicate_state)
  932.                 crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
  933.         else {
  934.                 if (!crtc->state)
  935.                         drm_atomic_helper_crtc_reset(crtc);
  936.  
  937.                 crtc_state = drm_atomic_helper_crtc_duplicate_state(crtc);
  938.         }
  939.  
  940.         if (!crtc_state)
  941.                 return -ENOMEM;
  942.  
  943.         crtc_state->planes_changed = true;
  944.         crtc_state->mode_changed = true;
  945.         ret = drm_atomic_set_mode_for_crtc(crtc_state, mode);
  946.         if (ret)
  947.                 goto out;
  948.         drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
  949.  
  950.         if (crtc_funcs->atomic_check) {
  951.                 ret = crtc_funcs->atomic_check(crtc, crtc_state);
  952.                 if (ret)
  953.                         goto out;
  954.         }
  955.  
  956.         swap(crtc->state, crtc_state);
  957.  
  958.         crtc_funcs->mode_set_nofb(crtc);
  959.  
  960.         ret = drm_helper_crtc_mode_set_base(crtc, x, y, old_fb);
  961.  
  962. out:
  963.         if (crtc_state) {
  964.                 if (crtc->funcs->atomic_destroy_state)
  965.                         crtc->funcs->atomic_destroy_state(crtc, crtc_state);
  966.                 else
  967.                         drm_atomic_helper_crtc_destroy_state(crtc, crtc_state);
  968.         }
  969.  
  970.         return ret;
  971. }
  972. EXPORT_SYMBOL(drm_helper_crtc_mode_set);
  973.  
  974. /**
  975.  * drm_helper_crtc_mode_set_base - mode_set_base implementation for atomic plane helpers
  976.  * @crtc: DRM CRTC
  977.  * @x: x offset of the CRTC scanout area on the underlying framebuffer
  978.  * @y: y offset of the CRTC scanout area on the underlying framebuffer
  979.  * @old_fb: previous framebuffer
  980.  *
  981.  * This function implements a callback useable as the ->mode_set_base used
  982.  * required by the crtc helpers. The driver must provide the atomic plane helper
  983.  * functions for the primary plane.
  984.  *
  985.  * This is a transitional helper useful for converting drivers to the atomic
  986.  * interfaces.
  987.  */
  988. int drm_helper_crtc_mode_set_base(struct drm_crtc *crtc, int x, int y,
  989.                                   struct drm_framebuffer *old_fb)
  990. {
  991.         struct drm_plane_state *plane_state;
  992.         struct drm_plane *plane = crtc->primary;
  993.  
  994.         if (plane->funcs->atomic_duplicate_state)
  995.                 plane_state = plane->funcs->atomic_duplicate_state(plane);
  996.         else if (plane->state)
  997.                 plane_state = drm_atomic_helper_plane_duplicate_state(plane);
  998.         else
  999.                 plane_state = kzalloc(sizeof(*plane_state), GFP_KERNEL);
  1000.         if (!plane_state)
  1001.                 return -ENOMEM;
  1002.         plane_state->plane = plane;
  1003.  
  1004.         plane_state->crtc = crtc;
  1005.         drm_atomic_set_fb_for_plane(plane_state, crtc->primary->fb);
  1006.         plane_state->crtc_x = 0;
  1007.         plane_state->crtc_y = 0;
  1008.         plane_state->crtc_h = crtc->mode.vdisplay;
  1009.         plane_state->crtc_w = crtc->mode.hdisplay;
  1010.         plane_state->src_x = x << 16;
  1011.         plane_state->src_y = y << 16;
  1012.         plane_state->src_h = crtc->mode.vdisplay << 16;
  1013.         plane_state->src_w = crtc->mode.hdisplay << 16;
  1014.  
  1015.         return drm_plane_helper_commit(plane, plane_state, old_fb);
  1016. }
  1017. EXPORT_SYMBOL(drm_helper_crtc_mode_set_base);
  1018.