1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * ChromeOS EC multi-function device 4 * 5 * Copyright (C) 2012 Google, Inc 6 * 7 * The ChromeOS EC multi function device is used to mux all the requests 8 * to the EC device for its multiple features: keyboard controller, 9 * battery charging and regulator control, firmware update. 10 */ 11 12 #include <linux/of_platform.h> 13 #include <linux/interrupt.h> 14 #include <linux/slab.h> 15 #include <linux/module.h> 16 #include <linux/platform_data/cros_ec_commands.h> 17 #include <linux/platform_data/cros_ec_proto.h> 18 #include <linux/suspend.h> 19 #include <asm/unaligned.h> 20 21 #define CROS_EC_DEV_EC_INDEX 0 22 #define CROS_EC_DEV_PD_INDEX 1 23 24 static struct cros_ec_platform ec_p = { 25 .ec_name = CROS_EC_DEV_NAME, 26 .cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX), 27 }; 28 29 static struct cros_ec_platform pd_p = { 30 .ec_name = CROS_EC_DEV_PD_NAME, 31 .cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX), 32 }; 33 34 static irqreturn_t ec_irq_thread(int irq, void *data) 35 { 36 struct cros_ec_device *ec_dev = data; 37 bool wake_event = true; 38 int ret; 39 40 ret = cros_ec_get_next_event(ec_dev, &wake_event); 41 42 /* 43 * Signal only if wake host events or any interrupt if 44 * cros_ec_get_next_event() returned an error (default value for 45 * wake_event is true) 46 */ 47 if (wake_event && device_may_wakeup(ec_dev->dev)) 48 pm_wakeup_event(ec_dev->dev, 0); 49 50 if (ret > 0) 51 blocking_notifier_call_chain(&ec_dev->event_notifier, 52 0, ec_dev); 53 return IRQ_HANDLED; 54 } 55 56 static int cros_ec_sleep_event(struct cros_ec_device *ec_dev, u8 sleep_event) 57 { 58 int ret; 59 struct { 60 struct cros_ec_command msg; 61 union { 62 struct ec_params_host_sleep_event req0; 63 struct ec_params_host_sleep_event_v1 req1; 64 struct ec_response_host_sleep_event_v1 resp1; 65 } u; 66 } __packed buf; 67 68 memset(&buf, 0, sizeof(buf)); 69 70 if (ec_dev->host_sleep_v1) { 71 buf.u.req1.sleep_event = sleep_event; 72 buf.u.req1.suspend_params.sleep_timeout_ms = 73 EC_HOST_SLEEP_TIMEOUT_DEFAULT; 74 75 buf.msg.outsize = sizeof(buf.u.req1); 76 if ((sleep_event == HOST_SLEEP_EVENT_S3_RESUME) || 77 (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME)) 78 buf.msg.insize = sizeof(buf.u.resp1); 79 80 buf.msg.version = 1; 81 82 } else { 83 buf.u.req0.sleep_event = sleep_event; 84 buf.msg.outsize = sizeof(buf.u.req0); 85 } 86 87 buf.msg.command = EC_CMD_HOST_SLEEP_EVENT; 88 89 ret = cros_ec_cmd_xfer(ec_dev, &buf.msg); 90 91 /* For now, report failure to transition to S0ix with a warning. */ 92 if (ret >= 0 && ec_dev->host_sleep_v1 && 93 (sleep_event == HOST_SLEEP_EVENT_S0IX_RESUME)) { 94 ec_dev->last_resume_result = 95 buf.u.resp1.resume_response.sleep_transitions; 96 97 WARN_ONCE(buf.u.resp1.resume_response.sleep_transitions & 98 EC_HOST_RESUME_SLEEP_TIMEOUT, 99 "EC detected sleep transition timeout. Total slp_s0 transitions: %d", 100 buf.u.resp1.resume_response.sleep_transitions & 101 EC_HOST_RESUME_SLEEP_TRANSITIONS_MASK); 102 } 103 104 return ret; 105 } 106 107 int cros_ec_register(struct cros_ec_device *ec_dev) 108 { 109 struct device *dev = ec_dev->dev; 110 int err = 0; 111 112 BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier); 113 114 ec_dev->max_request = sizeof(struct ec_params_hello); 115 ec_dev->max_response = sizeof(struct ec_response_get_protocol_info); 116 ec_dev->max_passthru = 0; 117 118 ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL); 119 if (!ec_dev->din) 120 return -ENOMEM; 121 122 ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL); 123 if (!ec_dev->dout) 124 return -ENOMEM; 125 126 mutex_init(&ec_dev->lock); 127 128 err = cros_ec_query_all(ec_dev); 129 if (err) { 130 dev_err(dev, "Cannot identify the EC: error %d\n", err); 131 return err; 132 } 133 134 if (ec_dev->irq) { 135 err = devm_request_threaded_irq(dev, ec_dev->irq, NULL, 136 ec_irq_thread, IRQF_TRIGGER_LOW | IRQF_ONESHOT, 137 "chromeos-ec", ec_dev); 138 if (err) { 139 dev_err(dev, "Failed to request IRQ %d: %d", 140 ec_dev->irq, err); 141 return err; 142 } 143 } 144 145 /* Register a platform device for the main EC instance */ 146 ec_dev->ec = platform_device_register_data(ec_dev->dev, "cros-ec-dev", 147 PLATFORM_DEVID_AUTO, &ec_p, 148 sizeof(struct cros_ec_platform)); 149 if (IS_ERR(ec_dev->ec)) { 150 dev_err(ec_dev->dev, 151 "Failed to create CrOS EC platform device\n"); 152 return PTR_ERR(ec_dev->ec); 153 } 154 155 if (ec_dev->max_passthru) { 156 /* 157 * Register a platform device for the PD behind the main EC. 158 * We make the following assumptions: 159 * - behind an EC, we have a pd 160 * - only one device added. 161 * - the EC is responsive at init time (it is not true for a 162 * sensor hub). 163 */ 164 ec_dev->pd = platform_device_register_data(ec_dev->dev, 165 "cros-ec-dev", 166 PLATFORM_DEVID_AUTO, &pd_p, 167 sizeof(struct cros_ec_platform)); 168 if (IS_ERR(ec_dev->pd)) { 169 dev_err(ec_dev->dev, 170 "Failed to create CrOS PD platform device\n"); 171 platform_device_unregister(ec_dev->ec); 172 return PTR_ERR(ec_dev->pd); 173 } 174 } 175 176 if (IS_ENABLED(CONFIG_OF) && dev->of_node) { 177 err = devm_of_platform_populate(dev); 178 if (err) { 179 platform_device_unregister(ec_dev->pd); 180 platform_device_unregister(ec_dev->ec); 181 dev_err(dev, "Failed to register sub-devices\n"); 182 return err; 183 } 184 } 185 186 /* 187 * Clear sleep event - this will fail harmlessly on platforms that 188 * don't implement the sleep event host command. 189 */ 190 err = cros_ec_sleep_event(ec_dev, 0); 191 if (err < 0) 192 dev_dbg(ec_dev->dev, "Error %d clearing sleep event to ec", 193 err); 194 195 dev_info(dev, "Chrome EC device registered\n"); 196 197 return 0; 198 } 199 EXPORT_SYMBOL(cros_ec_register); 200 201 int cros_ec_unregister(struct cros_ec_device *ec_dev) 202 { 203 if (ec_dev->pd) 204 platform_device_unregister(ec_dev->pd); 205 platform_device_unregister(ec_dev->ec); 206 207 return 0; 208 } 209 EXPORT_SYMBOL(cros_ec_unregister); 210 211 #ifdef CONFIG_PM_SLEEP 212 int cros_ec_suspend(struct cros_ec_device *ec_dev) 213 { 214 struct device *dev = ec_dev->dev; 215 int ret; 216 u8 sleep_event; 217 218 sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ? 219 HOST_SLEEP_EVENT_S3_SUSPEND : 220 HOST_SLEEP_EVENT_S0IX_SUSPEND; 221 222 ret = cros_ec_sleep_event(ec_dev, sleep_event); 223 if (ret < 0) 224 dev_dbg(ec_dev->dev, "Error %d sending suspend event to ec", 225 ret); 226 227 if (device_may_wakeup(dev)) 228 ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq); 229 230 disable_irq(ec_dev->irq); 231 ec_dev->was_wake_device = ec_dev->wake_enabled; 232 ec_dev->suspended = true; 233 234 return 0; 235 } 236 EXPORT_SYMBOL(cros_ec_suspend); 237 238 static void cros_ec_report_events_during_suspend(struct cros_ec_device *ec_dev) 239 { 240 while (ec_dev->mkbp_event_supported && 241 cros_ec_get_next_event(ec_dev, NULL) > 0) 242 blocking_notifier_call_chain(&ec_dev->event_notifier, 243 1, ec_dev); 244 } 245 246 int cros_ec_resume(struct cros_ec_device *ec_dev) 247 { 248 int ret; 249 u8 sleep_event; 250 251 ec_dev->suspended = false; 252 enable_irq(ec_dev->irq); 253 254 sleep_event = (!IS_ENABLED(CONFIG_ACPI) || pm_suspend_via_firmware()) ? 255 HOST_SLEEP_EVENT_S3_RESUME : 256 HOST_SLEEP_EVENT_S0IX_RESUME; 257 258 ret = cros_ec_sleep_event(ec_dev, sleep_event); 259 if (ret < 0) 260 dev_dbg(ec_dev->dev, "Error %d sending resume event to ec", 261 ret); 262 263 if (ec_dev->wake_enabled) { 264 disable_irq_wake(ec_dev->irq); 265 ec_dev->wake_enabled = 0; 266 } 267 /* 268 * Let the mfd devices know about events that occur during 269 * suspend. This way the clients know what to do with them. 270 */ 271 cros_ec_report_events_during_suspend(ec_dev); 272 273 274 return 0; 275 } 276 EXPORT_SYMBOL(cros_ec_resume); 277 278 #endif 279 280 MODULE_LICENSE("GPL"); 281 MODULE_DESCRIPTION("ChromeOS EC core driver"); 282