drivers/gpu/drm/tidss/tidss_encoder.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
   4  * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
   5  */
   6
   7 #include <linux/export.h>
   8
   9 #include <drm/drm_crtc.h>
  10 #include <drm/drm_crtc_helper.h>
  11 #include <drm/drm_of.h>
  12 #include <drm/drm_panel.h>
  13 #include <drm/drm_simple_kms_helper.h>
  14
  15 #include "tidss_crtc.h"
  16 #include "tidss_drv.h"
  17 #include "tidss_encoder.h"
  18
  19 static int tidss_encoder_atomic_check(struct drm_encoder *encoder,
  20                                       struct drm_crtc_state *crtc_state,
  21                                       struct drm_connector_state *conn_state)
  22 {
  23         struct drm_device *ddev = encoder->dev;
  24         struct tidss_crtc_state *tcrtc_state = to_tidss_crtc_state(crtc_state);
  25         struct drm_display_info *di = &conn_state->connector->display_info;
  26         struct drm_bridge *bridge;
  27         bool bus_flags_set = false;
  28
  29         dev_dbg(ddev->dev, "%s\n", __func__);
  30
  31         /*
  32          * Take the bus_flags from the first bridge that defines
  33          * bridge timings, or from the connector's display_info if no
  34          * bridge defines the timings.
  35          */
  36         drm_for_each_bridge_in_chain(encoder, bridge) {
  37                 if (!bridge->timings)
  38                         continue;
  39
  40                 tcrtc_state->bus_flags = bridge->timings->input_bus_flags;
  41                 bus_flags_set = true;
  42                 break;
  43         }
  44
  45         if (!di->bus_formats || di->num_bus_formats == 0)  {
  46                 dev_err(ddev->dev, "%s: No bus_formats in connected display\n",
  47                         __func__);
  48                 return -EINVAL;
  49         }
  50
  51         // XXX any cleaner way to set bus format and flags?
  52         tcrtc_state->bus_format = di->bus_formats[0];
  53         if (!bus_flags_set)
  54                 tcrtc_state->bus_flags = di->bus_flags;
  55
  56         return 0;
  57 }
  58
  59 static const struct drm_encoder_helper_funcs encoder_helper_funcs = {
  60         .atomic_check = tidss_encoder_atomic_check,
  61 };
  62
  63 struct drm_encoder *tidss_encoder_create(struct tidss_device *tidss,
  64                                          u32 encoder_type, u32 possible_crtcs)
  65 {
  66         struct drm_encoder *enc;
  67         int ret;
  68
  69         enc = devm_kzalloc(tidss->dev, sizeof(*enc), GFP_KERNEL);
  70         if (!enc)
  71                 return ERR_PTR(-ENOMEM);
  72
  73         enc->possible_crtcs = possible_crtcs;
  74
  75         ret = drm_simple_encoder_init(&tidss->ddev, enc, encoder_type);
  76         if (ret < 0)
  77                 return ERR_PTR(ret);
  78
  79         drm_encoder_helper_add(enc, &encoder_helper_funcs);
  80
  81         dev_dbg(tidss->dev, "Encoder create done\n");
  82
  83         return enc;
  84 }