12de89fd9SPi-Hsun Shih // SPDX-License-Identifier: GPL-2.0 22de89fd9SPi-Hsun Shih // 32de89fd9SPi-Hsun Shih // Copyright 2018 Google LLC. 42de89fd9SPi-Hsun Shih 52de89fd9SPi-Hsun Shih #include <linux/completion.h> 62de89fd9SPi-Hsun Shih #include <linux/delay.h> 72de89fd9SPi-Hsun Shih #include <linux/kernel.h> 82de89fd9SPi-Hsun Shih #include <linux/module.h> 92de89fd9SPi-Hsun Shih #include <linux/of.h> 10840d9f13SEnric Balletbo i Serra #include <linux/platform_data/cros_ec_commands.h> 11840d9f13SEnric Balletbo i Serra #include <linux/platform_data/cros_ec_proto.h> 122de89fd9SPi-Hsun Shih #include <linux/platform_device.h> 132de89fd9SPi-Hsun Shih #include <linux/rpmsg.h> 142de89fd9SPi-Hsun Shih #include <linux/slab.h> 152de89fd9SPi-Hsun Shih 16034dbec1SEnric Balletbo i Serra #include "cros_ec.h" 17034dbec1SEnric Balletbo i Serra 182de89fd9SPi-Hsun Shih #define EC_MSG_TIMEOUT_MS 200 192de89fd9SPi-Hsun Shih #define HOST_COMMAND_MARK 1 202de89fd9SPi-Hsun Shih #define HOST_EVENT_MARK 2 212de89fd9SPi-Hsun Shih 222de89fd9SPi-Hsun Shih /** 232de89fd9SPi-Hsun Shih * struct cros_ec_rpmsg_response - rpmsg message format from from EC. 242de89fd9SPi-Hsun Shih * 252de89fd9SPi-Hsun Shih * @type: The type of message, should be either HOST_COMMAND_MARK or 262de89fd9SPi-Hsun Shih * HOST_EVENT_MARK, representing that the message is a response to 272de89fd9SPi-Hsun Shih * host command, or a host event. 282de89fd9SPi-Hsun Shih * @data: ec_host_response for host command. 292de89fd9SPi-Hsun Shih */ 302de89fd9SPi-Hsun Shih struct cros_ec_rpmsg_response { 312de89fd9SPi-Hsun Shih u8 type; 322de89fd9SPi-Hsun Shih u8 data[] __aligned(4); 332de89fd9SPi-Hsun Shih }; 342de89fd9SPi-Hsun Shih 352de89fd9SPi-Hsun Shih /** 362de89fd9SPi-Hsun Shih * struct cros_ec_rpmsg - information about a EC over rpmsg. 372de89fd9SPi-Hsun Shih * 382de89fd9SPi-Hsun Shih * @rpdev: rpmsg device we are connected to 392de89fd9SPi-Hsun Shih * @xfer_ack: completion for host command transfer. 402de89fd9SPi-Hsun Shih * @host_event_work: Work struct for pending host event. 419a876ba5SEnric Balletbo i Serra * @ept: The rpmsg endpoint of this channel. 429a876ba5SEnric Balletbo i Serra * @has_pending_host_event: Boolean used to check if there is a pending event. 439a876ba5SEnric Balletbo i Serra * @probe_done: Flag to indicate that probe is done. 442de89fd9SPi-Hsun Shih */ 452de89fd9SPi-Hsun Shih struct cros_ec_rpmsg { 462de89fd9SPi-Hsun Shih struct rpmsg_device *rpdev; 472de89fd9SPi-Hsun Shih struct completion xfer_ack; 482de89fd9SPi-Hsun Shih struct work_struct host_event_work; 4971cddb70SPi-Hsun Shih struct rpmsg_endpoint *ept; 50f775ac78SPi-Hsun Shih bool has_pending_host_event; 51f775ac78SPi-Hsun Shih bool probe_done; 522de89fd9SPi-Hsun Shih }; 532de89fd9SPi-Hsun Shih 542de89fd9SPi-Hsun Shih /** 552de89fd9SPi-Hsun Shih * cros_ec_cmd_xfer_rpmsg - Transfer a message over rpmsg and receive the reply 562de89fd9SPi-Hsun Shih * 572de89fd9SPi-Hsun Shih * @ec_dev: ChromeOS EC device 582de89fd9SPi-Hsun Shih * @ec_msg: Message to transfer 592de89fd9SPi-Hsun Shih * 602de89fd9SPi-Hsun Shih * This is only used for old EC proto version, and is not supported for this 612de89fd9SPi-Hsun Shih * driver. 622de89fd9SPi-Hsun Shih * 632de89fd9SPi-Hsun Shih * Return: -EINVAL 642de89fd9SPi-Hsun Shih */ 652de89fd9SPi-Hsun Shih static int cros_ec_cmd_xfer_rpmsg(struct cros_ec_device *ec_dev, 662de89fd9SPi-Hsun Shih struct cros_ec_command *ec_msg) 672de89fd9SPi-Hsun Shih { 682de89fd9SPi-Hsun Shih return -EINVAL; 692de89fd9SPi-Hsun Shih } 702de89fd9SPi-Hsun Shih 712de89fd9SPi-Hsun Shih /** 722de89fd9SPi-Hsun Shih * cros_ec_pkt_xfer_rpmsg - Transfer a packet over rpmsg and receive the reply 732de89fd9SPi-Hsun Shih * 742de89fd9SPi-Hsun Shih * @ec_dev: ChromeOS EC device 752de89fd9SPi-Hsun Shih * @ec_msg: Message to transfer 762de89fd9SPi-Hsun Shih * 772de89fd9SPi-Hsun Shih * Return: number of bytes of the reply on success or negative error code. 782de89fd9SPi-Hsun Shih */ 792de89fd9SPi-Hsun Shih static int cros_ec_pkt_xfer_rpmsg(struct cros_ec_device *ec_dev, 802de89fd9SPi-Hsun Shih struct cros_ec_command *ec_msg) 812de89fd9SPi-Hsun Shih { 822de89fd9SPi-Hsun Shih struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv; 832de89fd9SPi-Hsun Shih struct ec_host_response *response; 842de89fd9SPi-Hsun Shih unsigned long timeout; 852de89fd9SPi-Hsun Shih int len; 862de89fd9SPi-Hsun Shih int ret; 872de89fd9SPi-Hsun Shih u8 sum; 882de89fd9SPi-Hsun Shih int i; 892de89fd9SPi-Hsun Shih 902de89fd9SPi-Hsun Shih ec_msg->result = 0; 912de89fd9SPi-Hsun Shih len = cros_ec_prepare_tx(ec_dev, ec_msg); 922de89fd9SPi-Hsun Shih dev_dbg(ec_dev->dev, "prepared, len=%d\n", len); 932de89fd9SPi-Hsun Shih 942de89fd9SPi-Hsun Shih reinit_completion(&ec_rpmsg->xfer_ack); 9571cddb70SPi-Hsun Shih ret = rpmsg_send(ec_rpmsg->ept, ec_dev->dout, len); 962de89fd9SPi-Hsun Shih if (ret) { 972de89fd9SPi-Hsun Shih dev_err(ec_dev->dev, "rpmsg send failed\n"); 982de89fd9SPi-Hsun Shih return ret; 992de89fd9SPi-Hsun Shih } 1002de89fd9SPi-Hsun Shih 1012de89fd9SPi-Hsun Shih timeout = msecs_to_jiffies(EC_MSG_TIMEOUT_MS); 1022de89fd9SPi-Hsun Shih ret = wait_for_completion_timeout(&ec_rpmsg->xfer_ack, timeout); 1032de89fd9SPi-Hsun Shih if (!ret) { 1042de89fd9SPi-Hsun Shih dev_err(ec_dev->dev, "rpmsg send timeout\n"); 1052de89fd9SPi-Hsun Shih return -EIO; 1062de89fd9SPi-Hsun Shih } 1072de89fd9SPi-Hsun Shih 1082de89fd9SPi-Hsun Shih /* check response error code */ 1092de89fd9SPi-Hsun Shih response = (struct ec_host_response *)ec_dev->din; 1102de89fd9SPi-Hsun Shih ec_msg->result = response->result; 1112de89fd9SPi-Hsun Shih 1122de89fd9SPi-Hsun Shih ret = cros_ec_check_result(ec_dev, ec_msg); 1132de89fd9SPi-Hsun Shih if (ret) 1142de89fd9SPi-Hsun Shih goto exit; 1152de89fd9SPi-Hsun Shih 1162de89fd9SPi-Hsun Shih if (response->data_len > ec_msg->insize) { 1172de89fd9SPi-Hsun Shih dev_err(ec_dev->dev, "packet too long (%d bytes, expected %d)", 1182de89fd9SPi-Hsun Shih response->data_len, ec_msg->insize); 1192de89fd9SPi-Hsun Shih ret = -EMSGSIZE; 1202de89fd9SPi-Hsun Shih goto exit; 1212de89fd9SPi-Hsun Shih } 1222de89fd9SPi-Hsun Shih 1232de89fd9SPi-Hsun Shih /* copy response packet payload and compute checksum */ 1242de89fd9SPi-Hsun Shih memcpy(ec_msg->data, ec_dev->din + sizeof(*response), 1252de89fd9SPi-Hsun Shih response->data_len); 1262de89fd9SPi-Hsun Shih 1272de89fd9SPi-Hsun Shih sum = 0; 1282de89fd9SPi-Hsun Shih for (i = 0; i < sizeof(*response) + response->data_len; i++) 1292de89fd9SPi-Hsun Shih sum += ec_dev->din[i]; 1302de89fd9SPi-Hsun Shih 1312de89fd9SPi-Hsun Shih if (sum) { 1322de89fd9SPi-Hsun Shih dev_err(ec_dev->dev, "bad packet checksum, calculated %x\n", 1332de89fd9SPi-Hsun Shih sum); 1342de89fd9SPi-Hsun Shih ret = -EBADMSG; 1352de89fd9SPi-Hsun Shih goto exit; 1362de89fd9SPi-Hsun Shih } 1372de89fd9SPi-Hsun Shih 1382de89fd9SPi-Hsun Shih ret = response->data_len; 1392de89fd9SPi-Hsun Shih exit: 1402de89fd9SPi-Hsun Shih if (ec_msg->command == EC_CMD_REBOOT_EC) 1412de89fd9SPi-Hsun Shih msleep(EC_REBOOT_DELAY_MS); 1422de89fd9SPi-Hsun Shih 1432de89fd9SPi-Hsun Shih return ret; 1442de89fd9SPi-Hsun Shih } 1452de89fd9SPi-Hsun Shih 1462de89fd9SPi-Hsun Shih static void 1472de89fd9SPi-Hsun Shih cros_ec_rpmsg_host_event_function(struct work_struct *host_event_work) 1482de89fd9SPi-Hsun Shih { 1492de89fd9SPi-Hsun Shih struct cros_ec_rpmsg *ec_rpmsg = container_of(host_event_work, 1502de89fd9SPi-Hsun Shih struct cros_ec_rpmsg, 1512de89fd9SPi-Hsun Shih host_event_work); 1522de89fd9SPi-Hsun Shih 153*24c69043SGwendal Grignou cros_ec_irq_thread(0, dev_get_drvdata(&ec_rpmsg->rpdev->dev)); 1542de89fd9SPi-Hsun Shih } 1552de89fd9SPi-Hsun Shih 1562de89fd9SPi-Hsun Shih static int cros_ec_rpmsg_callback(struct rpmsg_device *rpdev, void *data, 1572de89fd9SPi-Hsun Shih int len, void *priv, u32 src) 1582de89fd9SPi-Hsun Shih { 1592de89fd9SPi-Hsun Shih struct cros_ec_device *ec_dev = dev_get_drvdata(&rpdev->dev); 1602de89fd9SPi-Hsun Shih struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv; 1612de89fd9SPi-Hsun Shih struct cros_ec_rpmsg_response *resp; 1622de89fd9SPi-Hsun Shih 1632de89fd9SPi-Hsun Shih if (!len) { 1642de89fd9SPi-Hsun Shih dev_warn(ec_dev->dev, "rpmsg received empty response"); 1652de89fd9SPi-Hsun Shih return -EINVAL; 1662de89fd9SPi-Hsun Shih } 1672de89fd9SPi-Hsun Shih 1682de89fd9SPi-Hsun Shih resp = data; 1692de89fd9SPi-Hsun Shih len -= offsetof(struct cros_ec_rpmsg_response, data); 1702de89fd9SPi-Hsun Shih if (resp->type == HOST_COMMAND_MARK) { 1712de89fd9SPi-Hsun Shih if (len > ec_dev->din_size) { 1722de89fd9SPi-Hsun Shih dev_warn(ec_dev->dev, 1732de89fd9SPi-Hsun Shih "received length %d > din_size %d, truncating", 1742de89fd9SPi-Hsun Shih len, ec_dev->din_size); 1752de89fd9SPi-Hsun Shih len = ec_dev->din_size; 1762de89fd9SPi-Hsun Shih } 1772de89fd9SPi-Hsun Shih 1782de89fd9SPi-Hsun Shih memcpy(ec_dev->din, resp->data, len); 1792de89fd9SPi-Hsun Shih complete(&ec_rpmsg->xfer_ack); 1802de89fd9SPi-Hsun Shih } else if (resp->type == HOST_EVENT_MARK) { 181f775ac78SPi-Hsun Shih /* 182f775ac78SPi-Hsun Shih * If the host event is sent before cros_ec_register is 183f775ac78SPi-Hsun Shih * finished, queue the host event. 184f775ac78SPi-Hsun Shih */ 185f775ac78SPi-Hsun Shih if (ec_rpmsg->probe_done) 1862de89fd9SPi-Hsun Shih schedule_work(&ec_rpmsg->host_event_work); 187f775ac78SPi-Hsun Shih else 188f775ac78SPi-Hsun Shih ec_rpmsg->has_pending_host_event = true; 1892de89fd9SPi-Hsun Shih } else { 1902de89fd9SPi-Hsun Shih dev_warn(ec_dev->dev, "rpmsg received invalid type = %d", 1912de89fd9SPi-Hsun Shih resp->type); 1922de89fd9SPi-Hsun Shih return -EINVAL; 1932de89fd9SPi-Hsun Shih } 1942de89fd9SPi-Hsun Shih 1952de89fd9SPi-Hsun Shih return 0; 1962de89fd9SPi-Hsun Shih } 1972de89fd9SPi-Hsun Shih 19871cddb70SPi-Hsun Shih static struct rpmsg_endpoint * 19971cddb70SPi-Hsun Shih cros_ec_rpmsg_create_ept(struct rpmsg_device *rpdev) 20071cddb70SPi-Hsun Shih { 20171cddb70SPi-Hsun Shih struct rpmsg_channel_info chinfo = {}; 20271cddb70SPi-Hsun Shih 20371cddb70SPi-Hsun Shih strscpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE); 20471cddb70SPi-Hsun Shih chinfo.src = rpdev->src; 20571cddb70SPi-Hsun Shih chinfo.dst = RPMSG_ADDR_ANY; 20671cddb70SPi-Hsun Shih 20771cddb70SPi-Hsun Shih return rpmsg_create_ept(rpdev, cros_ec_rpmsg_callback, NULL, chinfo); 20871cddb70SPi-Hsun Shih } 20971cddb70SPi-Hsun Shih 2102de89fd9SPi-Hsun Shih static int cros_ec_rpmsg_probe(struct rpmsg_device *rpdev) 2112de89fd9SPi-Hsun Shih { 2122de89fd9SPi-Hsun Shih struct device *dev = &rpdev->dev; 2132de89fd9SPi-Hsun Shih struct cros_ec_rpmsg *ec_rpmsg; 2142de89fd9SPi-Hsun Shih struct cros_ec_device *ec_dev; 21571cddb70SPi-Hsun Shih int ret; 2162de89fd9SPi-Hsun Shih 2172de89fd9SPi-Hsun Shih ec_dev = devm_kzalloc(dev, sizeof(*ec_dev), GFP_KERNEL); 2182de89fd9SPi-Hsun Shih if (!ec_dev) 2192de89fd9SPi-Hsun Shih return -ENOMEM; 2202de89fd9SPi-Hsun Shih 2212de89fd9SPi-Hsun Shih ec_rpmsg = devm_kzalloc(dev, sizeof(*ec_rpmsg), GFP_KERNEL); 2222de89fd9SPi-Hsun Shih if (!ec_rpmsg) 2232de89fd9SPi-Hsun Shih return -ENOMEM; 2242de89fd9SPi-Hsun Shih 2252de89fd9SPi-Hsun Shih ec_dev->dev = dev; 2262de89fd9SPi-Hsun Shih ec_dev->priv = ec_rpmsg; 2272de89fd9SPi-Hsun Shih ec_dev->cmd_xfer = cros_ec_cmd_xfer_rpmsg; 2282de89fd9SPi-Hsun Shih ec_dev->pkt_xfer = cros_ec_pkt_xfer_rpmsg; 2292de89fd9SPi-Hsun Shih ec_dev->phys_name = dev_name(&rpdev->dev); 2302de89fd9SPi-Hsun Shih ec_dev->din_size = sizeof(struct ec_host_response) + 2312de89fd9SPi-Hsun Shih sizeof(struct ec_response_get_protocol_info); 2322de89fd9SPi-Hsun Shih ec_dev->dout_size = sizeof(struct ec_host_request); 2332de89fd9SPi-Hsun Shih dev_set_drvdata(dev, ec_dev); 2342de89fd9SPi-Hsun Shih 2352de89fd9SPi-Hsun Shih ec_rpmsg->rpdev = rpdev; 2362de89fd9SPi-Hsun Shih init_completion(&ec_rpmsg->xfer_ack); 2372de89fd9SPi-Hsun Shih INIT_WORK(&ec_rpmsg->host_event_work, 2382de89fd9SPi-Hsun Shih cros_ec_rpmsg_host_event_function); 2392de89fd9SPi-Hsun Shih 24071cddb70SPi-Hsun Shih ec_rpmsg->ept = cros_ec_rpmsg_create_ept(rpdev); 24171cddb70SPi-Hsun Shih if (!ec_rpmsg->ept) 24271cddb70SPi-Hsun Shih return -ENOMEM; 24371cddb70SPi-Hsun Shih 24471cddb70SPi-Hsun Shih ret = cros_ec_register(ec_dev); 24571cddb70SPi-Hsun Shih if (ret < 0) { 24671cddb70SPi-Hsun Shih rpmsg_destroy_ept(ec_rpmsg->ept); 24771cddb70SPi-Hsun Shih cancel_work_sync(&ec_rpmsg->host_event_work); 24871cddb70SPi-Hsun Shih return ret; 24971cddb70SPi-Hsun Shih } 25071cddb70SPi-Hsun Shih 251f775ac78SPi-Hsun Shih ec_rpmsg->probe_done = true; 252f775ac78SPi-Hsun Shih 253f775ac78SPi-Hsun Shih if (ec_rpmsg->has_pending_host_event) 254f775ac78SPi-Hsun Shih schedule_work(&ec_rpmsg->host_event_work); 255f775ac78SPi-Hsun Shih 25671cddb70SPi-Hsun Shih return 0; 2572de89fd9SPi-Hsun Shih } 2582de89fd9SPi-Hsun Shih 2592de89fd9SPi-Hsun Shih static void cros_ec_rpmsg_remove(struct rpmsg_device *rpdev) 2602de89fd9SPi-Hsun Shih { 2612de89fd9SPi-Hsun Shih struct cros_ec_device *ec_dev = dev_get_drvdata(&rpdev->dev); 2622de89fd9SPi-Hsun Shih struct cros_ec_rpmsg *ec_rpmsg = ec_dev->priv; 2632de89fd9SPi-Hsun Shih 2647aa703bbSEnric Balletbo i Serra cros_ec_unregister(ec_dev); 26571cddb70SPi-Hsun Shih rpmsg_destroy_ept(ec_rpmsg->ept); 2662de89fd9SPi-Hsun Shih cancel_work_sync(&ec_rpmsg->host_event_work); 2672de89fd9SPi-Hsun Shih } 2682de89fd9SPi-Hsun Shih 269058bf149SYilun Lin #ifdef CONFIG_PM_SLEEP 270058bf149SYilun Lin static int cros_ec_rpmsg_suspend(struct device *dev) 271058bf149SYilun Lin { 272058bf149SYilun Lin struct cros_ec_device *ec_dev = dev_get_drvdata(dev); 273058bf149SYilun Lin 274058bf149SYilun Lin return cros_ec_suspend(ec_dev); 275058bf149SYilun Lin } 276058bf149SYilun Lin 277058bf149SYilun Lin static int cros_ec_rpmsg_resume(struct device *dev) 278058bf149SYilun Lin { 279058bf149SYilun Lin struct cros_ec_device *ec_dev = dev_get_drvdata(dev); 280058bf149SYilun Lin 281058bf149SYilun Lin return cros_ec_resume(ec_dev); 282058bf149SYilun Lin } 283058bf149SYilun Lin #endif 284058bf149SYilun Lin 285058bf149SYilun Lin static SIMPLE_DEV_PM_OPS(cros_ec_rpmsg_pm_ops, cros_ec_rpmsg_suspend, 286058bf149SYilun Lin cros_ec_rpmsg_resume); 287058bf149SYilun Lin 2882de89fd9SPi-Hsun Shih static const struct of_device_id cros_ec_rpmsg_of_match[] = { 2892de89fd9SPi-Hsun Shih { .compatible = "google,cros-ec-rpmsg", }, 2902de89fd9SPi-Hsun Shih { } 2912de89fd9SPi-Hsun Shih }; 2922de89fd9SPi-Hsun Shih MODULE_DEVICE_TABLE(of, cros_ec_rpmsg_of_match); 2932de89fd9SPi-Hsun Shih 2942de89fd9SPi-Hsun Shih static struct rpmsg_driver cros_ec_driver_rpmsg = { 2952de89fd9SPi-Hsun Shih .drv = { 2962de89fd9SPi-Hsun Shih .name = "cros-ec-rpmsg", 2972de89fd9SPi-Hsun Shih .of_match_table = cros_ec_rpmsg_of_match, 298058bf149SYilun Lin .pm = &cros_ec_rpmsg_pm_ops, 2992de89fd9SPi-Hsun Shih }, 3002de89fd9SPi-Hsun Shih .probe = cros_ec_rpmsg_probe, 3012de89fd9SPi-Hsun Shih .remove = cros_ec_rpmsg_remove, 3022de89fd9SPi-Hsun Shih }; 3032de89fd9SPi-Hsun Shih 3042de89fd9SPi-Hsun Shih module_rpmsg_driver(cros_ec_driver_rpmsg); 3052de89fd9SPi-Hsun Shih 3062de89fd9SPi-Hsun Shih MODULE_LICENSE("GPL v2"); 3072de89fd9SPi-Hsun Shih MODULE_DESCRIPTION("ChromeOS EC multi function device (rpmsg)"); 308