xref: /linux/drivers/gpu/drm/mgag200/mgag200_vga_bmc.c (revision 815e260a18a3af4dab59025ee99a7156c0e8b5e0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <drm/drm_atomic_helper.h>
4 #include <drm/drm_edid.h>
5 #include <drm/drm_modeset_helper_vtables.h>
6 #include <drm/drm_print.h>
7 #include <drm/drm_probe_helper.h>
8 
9 #include "mgag200_ddc.h"
10 #include "mgag200_drv.h"
11 
12 static void mgag200_vga_bmc_encoder_atomic_disable(struct drm_encoder *encoder,
13 						   struct drm_atomic_state *state)
14 {
15 	struct mga_device *mdev = to_mga_device(encoder->dev);
16 
17 	if (mdev->info->sync_bmc)
18 		mgag200_bmc_stop_scanout(mdev);
19 }
20 
21 static void mgag200_vga_bmc_encoder_atomic_enable(struct drm_encoder *encoder,
22 						  struct drm_atomic_state *state)
23 {
24 	struct mga_device *mdev = to_mga_device(encoder->dev);
25 
26 	if (mdev->info->sync_bmc)
27 		mgag200_bmc_start_scanout(mdev);
28 }
29 
30 static int mgag200_vga_bmc_encoder_atomic_check(struct drm_encoder *encoder,
31 						struct drm_crtc_state *new_crtc_state,
32 						struct drm_connector_state *new_connector_state)
33 {
34 	struct mga_device *mdev = to_mga_device(encoder->dev);
35 	struct mgag200_crtc_state *new_mgag200_crtc_state = to_mgag200_crtc_state(new_crtc_state);
36 
37 	new_mgag200_crtc_state->set_vidrst = mdev->info->sync_bmc;
38 
39 	return 0;
40 }
41 
42 static const struct drm_encoder_helper_funcs mgag200_dac_encoder_helper_funcs = {
43 	.atomic_disable = mgag200_vga_bmc_encoder_atomic_disable,
44 	.atomic_enable = mgag200_vga_bmc_encoder_atomic_enable,
45 	.atomic_check = mgag200_vga_bmc_encoder_atomic_check,
46 };
47 
48 static const struct drm_encoder_funcs mgag200_dac_encoder_funcs = {
49 	.destroy = drm_encoder_cleanup
50 };
51 
52 static int mgag200_vga_bmc_connector_helper_get_modes(struct drm_connector *connector)
53 {
54 	struct mga_device *mdev = to_mga_device(connector->dev);
55 	const struct mgag200_device_info *minfo = mdev->info;
56 	int count;
57 
58 	count = drm_connector_helper_get_modes(connector);
59 
60 	if (!count) {
61 		/*
62 		 * There's no EDID data without a connected monitor. Set BMC-
63 		 * compatible modes in this case. The XGA default resolution
64 		 * should work well for all BMCs.
65 		 */
66 		count = drm_add_modes_noedid(connector, minfo->max_hdisplay, minfo->max_vdisplay);
67 		if (count)
68 			drm_set_preferred_mode(connector, 1024, 768);
69 	}
70 
71 	return count;
72 }
73 
74 /*
75  * There's no monitor connected if the DDC did not return an EDID. Still
76  * return 'connected' as there's always a BMC. Incrementing the connector's
77  * epoch counter triggers an update of the related properties.
78  */
79 static int mgag200_vga_bmc_connector_helper_detect_ctx(struct drm_connector *connector,
80 						       struct drm_modeset_acquire_ctx *ctx,
81 						       bool force)
82 {
83 	enum drm_connector_status old_status, status;
84 
85 	if (connector->edid_blob_ptr)
86 		old_status = connector_status_connected;
87 	else
88 		old_status = connector_status_disconnected;
89 
90 	status = drm_connector_helper_detect_from_ddc(connector, ctx, force);
91 
92 	if (status != old_status)
93 		++connector->epoch_counter;
94 	return connector_status_connected;
95 }
96 
97 static const struct drm_connector_helper_funcs mgag200_vga_connector_helper_funcs = {
98 	.get_modes = mgag200_vga_bmc_connector_helper_get_modes,
99 	.detect_ctx = mgag200_vga_bmc_connector_helper_detect_ctx,
100 };
101 
102 static const struct drm_connector_funcs mgag200_vga_connector_funcs = {
103 	.reset                  = drm_atomic_helper_connector_reset,
104 	.fill_modes             = drm_helper_probe_single_connector_modes,
105 	.destroy                = drm_connector_cleanup,
106 	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
107 	.atomic_destroy_state   = drm_atomic_helper_connector_destroy_state
108 };
109 
110 int mgag200_vga_bmc_output_init(struct mga_device *mdev)
111 {
112 	struct drm_device *dev = &mdev->base;
113 	struct drm_crtc *crtc = &mdev->crtc;
114 	struct drm_encoder *encoder;
115 	struct drm_connector *connector;
116 	struct i2c_adapter *ddc;
117 	int ret;
118 
119 	encoder = &mdev->output.vga.encoder;
120 	ret = drm_encoder_init(dev, encoder, &mgag200_dac_encoder_funcs,
121 			       DRM_MODE_ENCODER_DAC, NULL);
122 	if (ret) {
123 		drm_err(dev, "drm_encoder_init() failed: %d\n", ret);
124 		return ret;
125 	}
126 	drm_encoder_helper_add(encoder, &mgag200_dac_encoder_helper_funcs);
127 
128 	encoder->possible_crtcs = drm_crtc_mask(crtc);
129 
130 	ddc = mgag200_ddc_create(mdev);
131 	if (IS_ERR(ddc)) {
132 		ret = PTR_ERR(ddc);
133 		drm_err(dev, "failed to add DDC bus: %d\n", ret);
134 		return ret;
135 	}
136 
137 	connector = &mdev->output.vga.connector;
138 	ret = drm_connector_init_with_ddc(dev, connector,
139 					  &mgag200_vga_connector_funcs,
140 					  DRM_MODE_CONNECTOR_VGA, ddc);
141 	if (ret) {
142 		drm_err(dev, "drm_connector_init_with_ddc() failed: %d\n", ret);
143 		return ret;
144 	}
145 	drm_connector_helper_add(connector, &mgag200_vga_connector_helper_funcs);
146 
147 	connector->polled = DRM_CONNECTOR_POLL_CONNECT |
148 			    DRM_CONNECTOR_POLL_DISCONNECT;
149 
150 	ret = drm_connector_attach_encoder(connector, encoder);
151 	if (ret) {
152 		drm_err(dev, "drm_connector_attach_encoder() failed: %d\n", ret);
153 		return ret;
154 	}
155 
156 	return 0;
157 }
158