1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * CEC driver for ChromeOS Embedded Controller 4 * 5 * Copyright (c) 2018 BayLibre, SAS 6 * Author: Neil Armstrong <narmstrong@baylibre.com> 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/platform_device.h> 12 #include <linux/dmi.h> 13 #include <linux/pci.h> 14 #include <linux/cec.h> 15 #include <linux/slab.h> 16 #include <linux/interrupt.h> 17 #include <linux/platform_data/cros_ec_commands.h> 18 #include <linux/platform_data/cros_ec_proto.h> 19 #include <media/cec.h> 20 #include <media/cec-notifier.h> 21 22 #define DRV_NAME "cros-ec-cec" 23 24 /** 25 * struct cros_ec_cec - Driver data for EC CEC 26 * 27 * @cros_ec: Pointer to EC device 28 * @notifier: Notifier info for responding to EC events 29 * @adap: CEC adapter 30 * @notify: CEC notifier pointer 31 * @rx_msg: storage for a received message 32 */ 33 struct cros_ec_cec { 34 struct cros_ec_device *cros_ec; 35 struct notifier_block notifier; 36 struct cec_adapter *adap; 37 struct cec_notifier *notify; 38 struct cec_msg rx_msg; 39 }; 40 41 static void handle_cec_message(struct cros_ec_cec *cros_ec_cec) 42 { 43 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 44 uint8_t *cec_message = cros_ec->event_data.data.cec_message; 45 unsigned int len = cros_ec->event_size; 46 47 if (len > CEC_MAX_MSG_SIZE) 48 len = CEC_MAX_MSG_SIZE; 49 cros_ec_cec->rx_msg.len = len; 50 memcpy(cros_ec_cec->rx_msg.msg, cec_message, len); 51 52 cec_received_msg(cros_ec_cec->adap, &cros_ec_cec->rx_msg); 53 } 54 55 static void handle_cec_event(struct cros_ec_cec *cros_ec_cec) 56 { 57 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 58 uint32_t events = cros_ec->event_data.data.cec_events; 59 60 if (events & EC_MKBP_CEC_SEND_OK) 61 cec_transmit_attempt_done(cros_ec_cec->adap, 62 CEC_TX_STATUS_OK); 63 64 /* FW takes care of all retries, tell core to avoid more retries */ 65 if (events & EC_MKBP_CEC_SEND_FAILED) 66 cec_transmit_attempt_done(cros_ec_cec->adap, 67 CEC_TX_STATUS_MAX_RETRIES | 68 CEC_TX_STATUS_NACK); 69 } 70 71 static int cros_ec_cec_event(struct notifier_block *nb, 72 unsigned long queued_during_suspend, 73 void *_notify) 74 { 75 struct cros_ec_cec *cros_ec_cec; 76 struct cros_ec_device *cros_ec; 77 78 cros_ec_cec = container_of(nb, struct cros_ec_cec, notifier); 79 cros_ec = cros_ec_cec->cros_ec; 80 81 if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_EVENT) { 82 handle_cec_event(cros_ec_cec); 83 return NOTIFY_OK; 84 } 85 86 if (cros_ec->event_data.event_type == EC_MKBP_EVENT_CEC_MESSAGE) { 87 handle_cec_message(cros_ec_cec); 88 return NOTIFY_OK; 89 } 90 91 return NOTIFY_DONE; 92 } 93 94 static int cros_ec_cec_set_log_addr(struct cec_adapter *adap, u8 logical_addr) 95 { 96 struct cros_ec_cec *cros_ec_cec = adap->priv; 97 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 98 struct { 99 struct cros_ec_command msg; 100 struct ec_params_cec_set data; 101 } __packed msg = {}; 102 int ret; 103 104 msg.msg.command = EC_CMD_CEC_SET; 105 msg.msg.outsize = sizeof(msg.data); 106 msg.data.cmd = CEC_CMD_LOGICAL_ADDRESS; 107 msg.data.val = logical_addr; 108 109 ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg); 110 if (ret < 0) { 111 dev_err(cros_ec->dev, 112 "error setting CEC logical address on EC: %d\n", ret); 113 return ret; 114 } 115 116 return 0; 117 } 118 119 static int cros_ec_cec_transmit(struct cec_adapter *adap, u8 attempts, 120 u32 signal_free_time, struct cec_msg *cec_msg) 121 { 122 struct cros_ec_cec *cros_ec_cec = adap->priv; 123 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 124 struct { 125 struct cros_ec_command msg; 126 struct ec_params_cec_write data; 127 } __packed msg = {}; 128 int ret; 129 130 msg.msg.command = EC_CMD_CEC_WRITE_MSG; 131 msg.msg.outsize = cec_msg->len; 132 memcpy(msg.data.msg, cec_msg->msg, cec_msg->len); 133 134 ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg); 135 if (ret < 0) { 136 dev_err(cros_ec->dev, 137 "error writing CEC msg on EC: %d\n", ret); 138 return ret; 139 } 140 141 return 0; 142 } 143 144 static int cros_ec_cec_adap_enable(struct cec_adapter *adap, bool enable) 145 { 146 struct cros_ec_cec *cros_ec_cec = adap->priv; 147 struct cros_ec_device *cros_ec = cros_ec_cec->cros_ec; 148 struct { 149 struct cros_ec_command msg; 150 struct ec_params_cec_set data; 151 } __packed msg = {}; 152 int ret; 153 154 msg.msg.command = EC_CMD_CEC_SET; 155 msg.msg.outsize = sizeof(msg.data); 156 msg.data.cmd = CEC_CMD_ENABLE; 157 msg.data.val = enable; 158 159 ret = cros_ec_cmd_xfer_status(cros_ec, &msg.msg); 160 if (ret < 0) { 161 dev_err(cros_ec->dev, 162 "error %sabling CEC on EC: %d\n", 163 (enable ? "en" : "dis"), ret); 164 return ret; 165 } 166 167 return 0; 168 } 169 170 static const struct cec_adap_ops cros_ec_cec_ops = { 171 .adap_enable = cros_ec_cec_adap_enable, 172 .adap_log_addr = cros_ec_cec_set_log_addr, 173 .adap_transmit = cros_ec_cec_transmit, 174 }; 175 176 #ifdef CONFIG_PM_SLEEP 177 static int cros_ec_cec_suspend(struct device *dev) 178 { 179 struct platform_device *pdev = to_platform_device(dev); 180 struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev); 181 182 if (device_may_wakeup(dev)) 183 enable_irq_wake(cros_ec_cec->cros_ec->irq); 184 185 return 0; 186 } 187 188 static int cros_ec_cec_resume(struct device *dev) 189 { 190 struct platform_device *pdev = to_platform_device(dev); 191 struct cros_ec_cec *cros_ec_cec = dev_get_drvdata(&pdev->dev); 192 193 if (device_may_wakeup(dev)) 194 disable_irq_wake(cros_ec_cec->cros_ec->irq); 195 196 return 0; 197 } 198 #endif 199 200 static SIMPLE_DEV_PM_OPS(cros_ec_cec_pm_ops, 201 cros_ec_cec_suspend, cros_ec_cec_resume); 202 203 #if IS_ENABLED(CONFIG_PCI) && IS_ENABLED(CONFIG_DMI) 204 205 /* 206 * The Firmware only handles a single CEC interface tied to a single HDMI 207 * connector we specify along with the DRM device name handling the HDMI output 208 */ 209 210 struct cec_dmi_match { 211 const char *sys_vendor; 212 const char *product_name; 213 const char *devname; 214 const char *conn; 215 }; 216 217 static const struct cec_dmi_match cec_dmi_match_table[] = { 218 /* Google Fizz */ 219 { "Google", "Fizz", "0000:00:02.0", "Port B" }, 220 /* Google Brask */ 221 { "Google", "Brask", "0000:00:02.0", "Port B" }, 222 /* Google Moli */ 223 { "Google", "Moli", "0000:00:02.0", "Port B" }, 224 /* Google Kinox */ 225 { "Google", "Kinox", "0000:00:02.0", "Port B" }, 226 /* Google Kuldax */ 227 { "Google", "Kuldax", "0000:00:02.0", "Port B" }, 228 }; 229 230 static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev, 231 const char **conn) 232 { 233 int i; 234 235 for (i = 0 ; i < ARRAY_SIZE(cec_dmi_match_table) ; ++i) { 236 const struct cec_dmi_match *m = &cec_dmi_match_table[i]; 237 238 if (dmi_match(DMI_SYS_VENDOR, m->sys_vendor) && 239 dmi_match(DMI_PRODUCT_NAME, m->product_name)) { 240 struct device *d; 241 242 /* Find the device, bail out if not yet registered */ 243 d = bus_find_device_by_name(&pci_bus_type, NULL, 244 m->devname); 245 if (!d) 246 return ERR_PTR(-EPROBE_DEFER); 247 put_device(d); 248 *conn = m->conn; 249 return d; 250 } 251 } 252 253 /* Hardware support must be added in the cec_dmi_match_table */ 254 dev_warn(dev, "CEC notifier not configured for this hardware\n"); 255 256 return ERR_PTR(-ENODEV); 257 } 258 259 #else 260 261 static struct device *cros_ec_cec_find_hdmi_dev(struct device *dev, 262 const char **conn) 263 { 264 return ERR_PTR(-ENODEV); 265 } 266 267 #endif 268 269 static int cros_ec_cec_probe(struct platform_device *pdev) 270 { 271 struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent); 272 struct cros_ec_device *cros_ec = ec_dev->ec_dev; 273 struct cros_ec_cec *cros_ec_cec; 274 struct device *hdmi_dev; 275 const char *conn = NULL; 276 int ret; 277 278 hdmi_dev = cros_ec_cec_find_hdmi_dev(&pdev->dev, &conn); 279 if (IS_ERR(hdmi_dev)) 280 return PTR_ERR(hdmi_dev); 281 282 cros_ec_cec = devm_kzalloc(&pdev->dev, sizeof(*cros_ec_cec), 283 GFP_KERNEL); 284 if (!cros_ec_cec) 285 return -ENOMEM; 286 287 platform_set_drvdata(pdev, cros_ec_cec); 288 cros_ec_cec->cros_ec = cros_ec; 289 290 device_init_wakeup(&pdev->dev, 1); 291 292 cros_ec_cec->adap = cec_allocate_adapter(&cros_ec_cec_ops, cros_ec_cec, 293 DRV_NAME, 294 CEC_CAP_DEFAULTS | 295 CEC_CAP_CONNECTOR_INFO, 1); 296 if (IS_ERR(cros_ec_cec->adap)) 297 return PTR_ERR(cros_ec_cec->adap); 298 299 cros_ec_cec->notify = cec_notifier_cec_adap_register(hdmi_dev, conn, 300 cros_ec_cec->adap); 301 if (!cros_ec_cec->notify) { 302 ret = -ENOMEM; 303 goto out_probe_adapter; 304 } 305 306 /* Get CEC events from the EC. */ 307 cros_ec_cec->notifier.notifier_call = cros_ec_cec_event; 308 ret = blocking_notifier_chain_register(&cros_ec->event_notifier, 309 &cros_ec_cec->notifier); 310 if (ret) { 311 dev_err(&pdev->dev, "failed to register notifier\n"); 312 goto out_probe_notify; 313 } 314 315 ret = cec_register_adapter(cros_ec_cec->adap, &pdev->dev); 316 if (ret < 0) 317 goto out_probe_notify; 318 319 return 0; 320 321 out_probe_notify: 322 cec_notifier_cec_adap_unregister(cros_ec_cec->notify, 323 cros_ec_cec->adap); 324 out_probe_adapter: 325 cec_delete_adapter(cros_ec_cec->adap); 326 return ret; 327 } 328 329 static int cros_ec_cec_remove(struct platform_device *pdev) 330 { 331 struct cros_ec_cec *cros_ec_cec = platform_get_drvdata(pdev); 332 struct device *dev = &pdev->dev; 333 int ret; 334 335 ret = blocking_notifier_chain_unregister( 336 &cros_ec_cec->cros_ec->event_notifier, 337 &cros_ec_cec->notifier); 338 339 if (ret) { 340 dev_err(dev, "failed to unregister notifier\n"); 341 return ret; 342 } 343 344 cec_notifier_cec_adap_unregister(cros_ec_cec->notify, 345 cros_ec_cec->adap); 346 cec_unregister_adapter(cros_ec_cec->adap); 347 348 return 0; 349 } 350 351 static struct platform_driver cros_ec_cec_driver = { 352 .probe = cros_ec_cec_probe, 353 .remove = cros_ec_cec_remove, 354 .driver = { 355 .name = DRV_NAME, 356 .pm = &cros_ec_cec_pm_ops, 357 }, 358 }; 359 360 module_platform_driver(cros_ec_cec_driver); 361 362 MODULE_DESCRIPTION("CEC driver for ChromeOS ECs"); 363 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>"); 364 MODULE_LICENSE("GPL"); 365 MODULE_ALIAS("platform:" DRV_NAME); 366