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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@ideasonboard.com>4 */5 6#include <linux/gpio/consumer.h>7#include <linux/i2c.h>8#include <linux/interrupt.h>9#include <linux/media-bus-format.h>10#include <linux/module.h>11#include <linux/mutex.h>12#include <linux/of.h>13#include <linux/platform_device.h>14#include <linux/regulator/consumer.h>15 16#include <drm/drm_atomic_helper.h>17#include <drm/drm_bridge.h>18#include <drm/drm_edid.h>19 20struct display_connector {21 struct drm_bridge bridge;22 23 struct gpio_desc *hpd_gpio;24 int hpd_irq;25 26 struct regulator *supply;27 struct gpio_desc *ddc_en;28};29 30static inline struct display_connector *31to_display_connector(struct drm_bridge *bridge)32{33 return container_of(bridge, struct display_connector, bridge);34}35 36static int display_connector_attach(struct drm_bridge *bridge,37 enum drm_bridge_attach_flags flags)38{39 return flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR ? 0 : -EINVAL;40}41 42static enum drm_connector_status43display_connector_detect(struct drm_bridge *bridge)44{45 struct display_connector *conn = to_display_connector(bridge);46 47 if (conn->hpd_gpio) {48 if (gpiod_get_value_cansleep(conn->hpd_gpio))49 return connector_status_connected;50 else51 return connector_status_disconnected;52 }53 54 if (conn->bridge.ddc && drm_probe_ddc(conn->bridge.ddc))55 return connector_status_connected;56 57 switch (conn->bridge.type) {58 case DRM_MODE_CONNECTOR_DVIA:59 case DRM_MODE_CONNECTOR_DVID:60 case DRM_MODE_CONNECTOR_DVII:61 case DRM_MODE_CONNECTOR_HDMIA:62 case DRM_MODE_CONNECTOR_HDMIB:63 /*64 * For DVI and HDMI connectors a DDC probe failure indicates65 * that no cable is connected.66 */67 return connector_status_disconnected;68 69 case DRM_MODE_CONNECTOR_Composite:70 case DRM_MODE_CONNECTOR_SVIDEO:71 case DRM_MODE_CONNECTOR_VGA:72 default:73 /*74 * Composite and S-Video connectors have no other detection75 * mean than the HPD GPIO. For VGA connectors, even if we have76 * an I2C bus, we can't assume that the cable is disconnected77 * if drm_probe_ddc fails, as some cables don't wire the DDC78 * pins.79 */80 return connector_status_unknown;81 }82}83 84static const struct drm_edid *display_connector_edid_read(struct drm_bridge *bridge,85 struct drm_connector *connector)86{87 struct display_connector *conn = to_display_connector(bridge);88 89 return drm_edid_read_ddc(connector, conn->bridge.ddc);90}91 92/*93 * Since this bridge is tied to the connector, it acts like a passthrough,94 * so concerning the output bus formats, either pass the bus formats from the95 * previous bridge or return fallback data like done in the bridge function:96 * drm_atomic_bridge_chain_select_bus_fmts().97 * This supports negotiation if the bridge chain has all bits in place.98 */99static u32 *display_connector_get_output_bus_fmts(struct drm_bridge *bridge,100 struct drm_bridge_state *bridge_state,101 struct drm_crtc_state *crtc_state,102 struct drm_connector_state *conn_state,103 unsigned int *num_output_fmts)104{105 struct drm_bridge *prev_bridge = drm_bridge_get_prev_bridge(bridge);106 struct drm_bridge_state *prev_bridge_state;107 108 if (!prev_bridge || !prev_bridge->funcs->atomic_get_output_bus_fmts) {109 struct drm_connector *conn = conn_state->connector;110 u32 *out_bus_fmts;111 112 *num_output_fmts = 1;113 out_bus_fmts = kmalloc(sizeof(*out_bus_fmts), GFP_KERNEL);114 if (!out_bus_fmts)115 return NULL;116 117 if (conn->display_info.num_bus_formats &&118 conn->display_info.bus_formats)119 out_bus_fmts[0] = conn->display_info.bus_formats[0];120 else121 out_bus_fmts[0] = MEDIA_BUS_FMT_FIXED;122 123 return out_bus_fmts;124 }125 126 prev_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,127 prev_bridge);128 129 return prev_bridge->funcs->atomic_get_output_bus_fmts(prev_bridge, prev_bridge_state,130 crtc_state, conn_state,131 num_output_fmts);132}133 134/*135 * Since this bridge is tied to the connector, it acts like a passthrough,136 * so concerning the input bus formats, either pass the bus formats from the137 * previous bridge or MEDIA_BUS_FMT_FIXED (like select_bus_fmt_recursive())138 * when atomic_get_input_bus_fmts is not supported.139 * This supports negotiation if the bridge chain has all bits in place.140 */141static u32 *display_connector_get_input_bus_fmts(struct drm_bridge *bridge,142 struct drm_bridge_state *bridge_state,143 struct drm_crtc_state *crtc_state,144 struct drm_connector_state *conn_state,145 u32 output_fmt,146 unsigned int *num_input_fmts)147{148 struct drm_bridge *prev_bridge = drm_bridge_get_prev_bridge(bridge);149 struct drm_bridge_state *prev_bridge_state;150 151 if (!prev_bridge || !prev_bridge->funcs->atomic_get_input_bus_fmts) {152 u32 *in_bus_fmts;153 154 *num_input_fmts = 1;155 in_bus_fmts = kmalloc(sizeof(*in_bus_fmts), GFP_KERNEL);156 if (!in_bus_fmts)157 return NULL;158 159 in_bus_fmts[0] = MEDIA_BUS_FMT_FIXED;160 161 return in_bus_fmts;162 }163 164 prev_bridge_state = drm_atomic_get_new_bridge_state(crtc_state->state,165 prev_bridge);166 167 return prev_bridge->funcs->atomic_get_input_bus_fmts(prev_bridge, prev_bridge_state,168 crtc_state, conn_state, output_fmt,169 num_input_fmts);170}171 172static const struct drm_bridge_funcs display_connector_bridge_funcs = {173 .attach = display_connector_attach,174 .detect = display_connector_detect,175 .edid_read = display_connector_edid_read,176 .atomic_get_output_bus_fmts = display_connector_get_output_bus_fmts,177 .atomic_get_input_bus_fmts = display_connector_get_input_bus_fmts,178 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,179 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,180 .atomic_reset = drm_atomic_helper_bridge_reset,181};182 183static irqreturn_t display_connector_hpd_irq(int irq, void *arg)184{185 struct display_connector *conn = arg;186 struct drm_bridge *bridge = &conn->bridge;187 188 drm_bridge_hpd_notify(bridge, display_connector_detect(bridge));189 190 return IRQ_HANDLED;191}192 193static int display_connector_get_supply(struct platform_device *pdev,194 struct display_connector *conn,195 const char *name)196{197 conn->supply = devm_regulator_get_optional(&pdev->dev, name);198 199 if (conn->supply == ERR_PTR(-ENODEV))200 conn->supply = NULL;201 202 return PTR_ERR_OR_ZERO(conn->supply);203}204 205static int display_connector_probe(struct platform_device *pdev)206{207 struct display_connector *conn;208 unsigned int type;209 const char *label = NULL;210 int ret;211 212 conn = devm_kzalloc(&pdev->dev, sizeof(*conn), GFP_KERNEL);213 if (!conn)214 return -ENOMEM;215 216 platform_set_drvdata(pdev, conn);217 218 type = (uintptr_t)of_device_get_match_data(&pdev->dev);219 220 /* Get the exact connector type. */221 switch (type) {222 case DRM_MODE_CONNECTOR_DVII: {223 bool analog, digital;224 225 analog = of_property_read_bool(pdev->dev.of_node, "analog");226 digital = of_property_read_bool(pdev->dev.of_node, "digital");227 if (analog && !digital) {228 conn->bridge.type = DRM_MODE_CONNECTOR_DVIA;229 } else if (!analog && digital) {230 conn->bridge.type = DRM_MODE_CONNECTOR_DVID;231 } else if (analog && digital) {232 conn->bridge.type = DRM_MODE_CONNECTOR_DVII;233 } else {234 dev_err(&pdev->dev, "DVI connector with no type\n");235 return -EINVAL;236 }237 break;238 }239 240 case DRM_MODE_CONNECTOR_HDMIA: {241 const char *hdmi_type;242 243 ret = of_property_read_string(pdev->dev.of_node, "type",244 &hdmi_type);245 if (ret < 0) {246 dev_err(&pdev->dev, "HDMI connector with no type\n");247 return -EINVAL;248 }249 250 if (!strcmp(hdmi_type, "a") || !strcmp(hdmi_type, "c") ||251 !strcmp(hdmi_type, "d") || !strcmp(hdmi_type, "e")) {252 conn->bridge.type = DRM_MODE_CONNECTOR_HDMIA;253 } else if (!strcmp(hdmi_type, "b")) {254 conn->bridge.type = DRM_MODE_CONNECTOR_HDMIB;255 } else {256 dev_err(&pdev->dev,257 "Unsupported HDMI connector type '%s'\n",258 hdmi_type);259 return -EINVAL;260 }261 262 break;263 }264 265 default:266 conn->bridge.type = type;267 break;268 }269 270 /* All the supported connector types support interlaced modes. */271 conn->bridge.interlace_allowed = true;272 273 /* Get the optional connector label. */274 of_property_read_string(pdev->dev.of_node, "label", &label);275 276 /*277 * Get the HPD GPIO for DVI, HDMI and DP connectors. If the GPIO can provide278 * edge interrupts, register an interrupt handler.279 */280 if (type == DRM_MODE_CONNECTOR_DVII ||281 type == DRM_MODE_CONNECTOR_HDMIA ||282 type == DRM_MODE_CONNECTOR_DisplayPort) {283 conn->hpd_gpio = devm_gpiod_get_optional(&pdev->dev, "hpd",284 GPIOD_IN);285 if (IS_ERR(conn->hpd_gpio))286 return dev_err_probe(&pdev->dev, PTR_ERR(conn->hpd_gpio),287 "Unable to retrieve HPD GPIO\n");288 289 conn->hpd_irq = gpiod_to_irq(conn->hpd_gpio);290 } else {291 conn->hpd_irq = -EINVAL;292 }293 294 if (conn->hpd_irq >= 0) {295 ret = devm_request_threaded_irq(&pdev->dev, conn->hpd_irq,296 NULL, display_connector_hpd_irq,297 IRQF_TRIGGER_RISING |298 IRQF_TRIGGER_FALLING |299 IRQF_ONESHOT,300 "HPD", conn);301 if (ret) {302 dev_info(&pdev->dev,303 "Failed to request HPD edge interrupt, falling back to polling\n");304 conn->hpd_irq = -EINVAL;305 }306 }307 308 /* Retrieve the DDC I2C adapter for DVI, HDMI and VGA connectors. */309 if (type == DRM_MODE_CONNECTOR_DVII ||310 type == DRM_MODE_CONNECTOR_HDMIA ||311 type == DRM_MODE_CONNECTOR_VGA) {312 struct device_node *phandle;313 314 phandle = of_parse_phandle(pdev->dev.of_node, "ddc-i2c-bus", 0);315 if (phandle) {316 conn->bridge.ddc = of_get_i2c_adapter_by_node(phandle);317 of_node_put(phandle);318 if (!conn->bridge.ddc)319 return -EPROBE_DEFER;320 } else {321 dev_dbg(&pdev->dev,322 "No I2C bus specified, disabling EDID readout\n");323 }324 }325 326 /* Get the DP PWR for DP connector. */327 if (type == DRM_MODE_CONNECTOR_DisplayPort) {328 int ret;329 330 ret = display_connector_get_supply(pdev, conn, "dp-pwr");331 if (ret < 0)332 return dev_err_probe(&pdev->dev, ret, "failed to get DP PWR regulator\n");333 }334 335 /* enable DDC */336 if (type == DRM_MODE_CONNECTOR_HDMIA) {337 int ret;338 339 conn->ddc_en = devm_gpiod_get_optional(&pdev->dev, "ddc-en",340 GPIOD_OUT_HIGH);341 342 if (IS_ERR(conn->ddc_en)) {343 dev_err(&pdev->dev, "Couldn't get ddc-en gpio\n");344 return PTR_ERR(conn->ddc_en);345 }346 347 ret = display_connector_get_supply(pdev, conn, "hdmi-pwr");348 if (ret < 0)349 return dev_err_probe(&pdev->dev, ret, "failed to get HDMI +5V Power regulator\n");350 }351 352 if (conn->supply) {353 ret = regulator_enable(conn->supply);354 if (ret) {355 dev_err(&pdev->dev, "failed to enable PWR regulator: %d\n", ret);356 return ret;357 }358 }359 360 conn->bridge.funcs = &display_connector_bridge_funcs;361 conn->bridge.of_node = pdev->dev.of_node;362 363 if (conn->bridge.ddc)364 conn->bridge.ops |= DRM_BRIDGE_OP_EDID365 | DRM_BRIDGE_OP_DETECT;366 if (conn->hpd_gpio)367 conn->bridge.ops |= DRM_BRIDGE_OP_DETECT;368 if (conn->hpd_irq >= 0)369 conn->bridge.ops |= DRM_BRIDGE_OP_HPD;370 371 dev_dbg(&pdev->dev,372 "Found %s display connector '%s' %s DDC bus and %s HPD GPIO (ops 0x%x)\n",373 drm_get_connector_type_name(conn->bridge.type),374 label ? label : "<unlabelled>",375 conn->bridge.ddc ? "with" : "without",376 conn->hpd_gpio ? "with" : "without",377 conn->bridge.ops);378 379 drm_bridge_add(&conn->bridge);380 381 return 0;382}383 384static void display_connector_remove(struct platform_device *pdev)385{386 struct display_connector *conn = platform_get_drvdata(pdev);387 388 if (conn->ddc_en)389 gpiod_set_value(conn->ddc_en, 0);390 391 if (conn->supply)392 regulator_disable(conn->supply);393 394 drm_bridge_remove(&conn->bridge);395 396 if (!IS_ERR(conn->bridge.ddc))397 i2c_put_adapter(conn->bridge.ddc);398}399 400static const struct of_device_id display_connector_match[] = {401 {402 .compatible = "composite-video-connector",403 .data = (void *)DRM_MODE_CONNECTOR_Composite,404 }, {405 .compatible = "dvi-connector",406 .data = (void *)DRM_MODE_CONNECTOR_DVII,407 }, {408 .compatible = "hdmi-connector",409 .data = (void *)DRM_MODE_CONNECTOR_HDMIA,410 }, {411 .compatible = "svideo-connector",412 .data = (void *)DRM_MODE_CONNECTOR_SVIDEO,413 }, {414 .compatible = "vga-connector",415 .data = (void *)DRM_MODE_CONNECTOR_VGA,416 }, {417 .compatible = "dp-connector",418 .data = (void *)DRM_MODE_CONNECTOR_DisplayPort,419 },420 {},421};422MODULE_DEVICE_TABLE(of, display_connector_match);423 424static struct platform_driver display_connector_driver = {425 .probe = display_connector_probe,426 .remove_new = display_connector_remove,427 .driver = {428 .name = "display-connector",429 .of_match_table = display_connector_match,430 },431};432module_platform_driver(display_connector_driver);433 434MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");435MODULE_DESCRIPTION("Display connector driver");436MODULE_LICENSE("GPL");437