1 // SPDX-License-Identifier: GPL-2.0-or-later
3  * Copyright (C) 2015-2016 Free Electrons
4  * Copyright (C) 2015-2016 NextThing Co
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
23 	struct i2c_adapter	*ddc;  member
45 	if (!vga->ddc)  in dumb_vga_get_modes()
48 	edid = drm_get_edid(connector, vga->ddc);  in dumb_vga_get_modes()
61 	 * In case we cannot retrieve the EDIDs (broken or missing i2c  in dumb_vga_get_modes()
62 	 * bus), fallback on the XGA standards  in dumb_vga_get_modes()
82 	 * Even if we have an I2C bus, we can't assume that the cable  in dumb_vga_connector_detect()
84 	 * wire the DDC pins, or the I2C bus might not be working at  in dumb_vga_connector_detect()
87 	if (vga->ddc && drm_probe_ddc(vga->ddc))  in dumb_vga_connector_detect()
107 	if (!bridge->encoder) {  in dumb_vga_attach()
109 		return -ENODEV;  in dumb_vga_attach()
112 	drm_connector_helper_add(&vga->connector,  in dumb_vga_attach()
114 	ret = drm_connector_init_with_ddc(bridge->dev, &vga->connector,  in dumb_vga_attach()
117 					  vga->ddc);  in dumb_vga_attach()
123 	drm_connector_attach_encoder(&vga->connector,  in dumb_vga_attach()
124 					  bridge->encoder);  in dumb_vga_attach()
134 	if (vga->vdd)  in dumb_vga_enable()
135 		ret = regulator_enable(vga->vdd);  in dumb_vga_enable()
145 	if (vga->vdd)  in dumb_vga_disable()
146 		regulator_disable(vga->vdd);  in dumb_vga_disable()
158 	struct i2c_adapter *ddc;  in dumb_vga_retrieve_ddc()  local
160 	remote = of_graph_get_remote_node(dev->of_node, 1, -1);  in dumb_vga_retrieve_ddc()
162 		return ERR_PTR(-EINVAL);  in dumb_vga_retrieve_ddc()
164 	phandle = of_parse_phandle(remote, "ddc-i2c-bus", 0);  in dumb_vga_retrieve_ddc()
167 		return ERR_PTR(-ENODEV);  in dumb_vga_retrieve_ddc()
169 	ddc = of_get_i2c_adapter_by_node(phandle);  in dumb_vga_retrieve_ddc()
171 	if (!ddc)  in dumb_vga_retrieve_ddc()
172 		return ERR_PTR(-EPROBE_DEFER);  in dumb_vga_retrieve_ddc()
174 	return ddc;  in dumb_vga_retrieve_ddc()
181 	vga = devm_kzalloc(&pdev->dev, sizeof(*vga), GFP_KERNEL);  in dumb_vga_probe()
183 		return -ENOMEM;  in dumb_vga_probe()
186 	vga->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");  in dumb_vga_probe()
187 	if (IS_ERR(vga->vdd)) {  in dumb_vga_probe()
188 		int ret = PTR_ERR(vga->vdd);  in dumb_vga_probe()
189 		if (ret == -EPROBE_DEFER)  in dumb_vga_probe()
190 			return -EPROBE_DEFER;  in dumb_vga_probe()
191 		vga->vdd = NULL;  in dumb_vga_probe()
192 		dev_dbg(&pdev->dev, "No vdd regulator found: %d\n", ret);  in dumb_vga_probe()
195 	vga->ddc = dumb_vga_retrieve_ddc(&pdev->dev);  in dumb_vga_probe()
196 	if (IS_ERR(vga->ddc)) {  in dumb_vga_probe()
197 		if (PTR_ERR(vga->ddc) == -ENODEV) {  in dumb_vga_probe()
198 			dev_dbg(&pdev->dev,  in dumb_vga_probe()
199 				"No i2c bus specified. Disabling EDID readout\n");  in dumb_vga_probe()
200 			vga->ddc = NULL;  in dumb_vga_probe()
202 			dev_err(&pdev->dev, "Couldn't retrieve i2c bus\n");  in dumb_vga_probe()
203 			return PTR_ERR(vga->ddc);  in dumb_vga_probe()
207 	vga->bridge.funcs = &dumb_vga_bridge_funcs;  in dumb_vga_probe()
208 	vga->bridge.of_node = pdev->dev.of_node;  in dumb_vga_probe()
209 	vga->bridge.timings = of_device_get_match_data(&pdev->dev);  in dumb_vga_probe()
211 	drm_bridge_add(&vga->bridge);  in dumb_vga_probe()
220 	drm_bridge_remove(&vga->bridge);  in dumb_vga_remove()
222 	if (vga->ddc)  in dumb_vga_remove()
223 		i2c_put_adapter(vga->ddc);  in dumb_vga_remove()
268 		.compatible = "dumb-vga-dac",
291 		.name		= "dumb-vga-dac",
297 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");