1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * ChromeOS Embedded Controller protocol interface. 4 * 5 * Copyright (C) 2012 Google, Inc 6 */ 7 8 #ifndef __LINUX_CROS_EC_PROTO_H 9 #define __LINUX_CROS_EC_PROTO_H 10 11 #include <linux/device.h> 12 #include <linux/lockdep_types.h> 13 #include <linux/mutex.h> 14 #include <linux/notifier.h> 15 16 #include <linux/platform_data/cros_ec_commands.h> 17 18 #define CROS_EC_DEV_NAME "cros_ec" 19 #define CROS_EC_DEV_FP_NAME "cros_fp" 20 #define CROS_EC_DEV_ISH_NAME "cros_ish" 21 #define CROS_EC_DEV_PD_NAME "cros_pd" 22 #define CROS_EC_DEV_SCP_NAME "cros_scp" 23 #define CROS_EC_DEV_TP_NAME "cros_tp" 24 25 #define CROS_EC_DEV_EC_INDEX 0 26 #define CROS_EC_DEV_PD_INDEX 1 27 28 /* 29 * The EC is unresponsive for a time after a reboot command. Add a 30 * simple delay to make sure that the bus stays locked. 31 */ 32 #define EC_REBOOT_DELAY_MS 50 33 34 /* 35 * Max bus-specific overhead incurred by request/responses. 36 * I2C requires 1 additional byte for requests. 37 * I2C requires 2 additional bytes for responses. 38 * SPI requires up to 32 additional bytes for responses. 39 */ 40 #define EC_PROTO_VERSION_UNKNOWN 0 41 #define EC_MAX_REQUEST_OVERHEAD 1 42 #define EC_MAX_RESPONSE_OVERHEAD 32 43 44 /* 45 * ACPI notify value for MKBP host event. 46 */ 47 #define ACPI_NOTIFY_CROS_EC_MKBP 0x80 48 49 /* 50 * EC panic is not covered by the standard (0-F) ACPI notify values. 51 * Arbitrarily choosing B0 to notify ec panic, which is in the 84-BF 52 * device specific ACPI notify range. 53 */ 54 #define ACPI_NOTIFY_CROS_EC_PANIC 0xB0 55 56 /* 57 * Command interface between EC and AP, for LPC, I2C and SPI interfaces. 58 */ 59 enum { 60 EC_MSG_TX_HEADER_BYTES = 3, 61 EC_MSG_TX_TRAILER_BYTES = 1, 62 EC_MSG_TX_PROTO_BYTES = EC_MSG_TX_HEADER_BYTES + 63 EC_MSG_TX_TRAILER_BYTES, 64 EC_MSG_RX_PROTO_BYTES = 3, 65 66 /* Max length of messages for proto 2*/ 67 EC_PROTO2_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE + 68 EC_MSG_TX_PROTO_BYTES, 69 70 EC_MAX_MSG_BYTES = 64 * 1024, 71 }; 72 73 /** 74 * struct cros_ec_command - Information about a ChromeOS EC command. 75 * @version: Command version number (often 0). 76 * @command: Command to send (EC_CMD_...). 77 * @outsize: Outgoing length in bytes. 78 * @insize: Max number of bytes to accept from the EC. 79 * @result: EC's response to the command (separate from communication failure). 80 * @data: Where to put the incoming data from EC and outgoing data to EC. 81 */ 82 struct cros_ec_command { 83 uint32_t version; 84 uint32_t command; 85 uint32_t outsize; 86 uint32_t insize; 87 uint32_t result; 88 uint8_t data[]; 89 }; 90 91 /** 92 * struct cros_ec_device - Information about a ChromeOS EC device. 93 * @phys_name: Name of physical comms layer (e.g. 'i2c-4'). 94 * @dev: Device pointer for physical comms device 95 * @cros_class: The class structure for this device. 96 * @cmd_readmem: Direct read of the EC memory-mapped region, if supported. 97 * @offset: Is within EC_LPC_ADDR_MEMMAP region. 98 * @bytes: Number of bytes to read. zero means "read a string" (including 99 * the trailing '\0'). At most only EC_MEMMAP_SIZE bytes can be 100 * read. Caller must ensure that the buffer is large enough for the 101 * result when reading a string. 102 * @max_request: Max size of message requested. 103 * @max_response: Max size of message response. 104 * @max_passthru: Max sice of passthru message. 105 * @proto_version: The protocol version used for this device. 106 * @priv: Private data. 107 * @irq: Interrupt to use. 108 * @id: Device id. 109 * @din: Input buffer (for data from EC). This buffer will always be 110 * dword-aligned and include enough space for up to 7 word-alignment 111 * bytes also, so we can ensure that the body of the message is always 112 * dword-aligned (64-bit). We use this alignment to keep ARM and x86 113 * happy. Probably word alignment would be OK, there might be a small 114 * performance advantage to using dword. 115 * @dout: Output buffer (for data to EC). This buffer will always be 116 * dword-aligned and include enough space for up to 7 word-alignment 117 * bytes also, so we can ensure that the body of the message is always 118 * dword-aligned (64-bit). We use this alignment to keep ARM and x86 119 * happy. Probably word alignment would be OK, there might be a small 120 * performance advantage to using dword. 121 * @din_size: Size of din buffer to allocate (zero to use static din). 122 * @dout_size: Size of dout buffer to allocate (zero to use static dout). 123 * @wake_enabled: True if this device can wake the system from sleep. 124 * @suspended: True if this device had been suspended. 125 * @cmd_xfer: Send command to EC and get response. 126 * Returns the number of bytes received if the communication 127 * succeeded, but that doesn't mean the EC was happy with the 128 * command. The caller should check msg.result for the EC's result 129 * code. 130 * @pkt_xfer: Send packet to EC and get response. 131 * @lockdep_key: Lockdep class for each instance. Unused if CONFIG_LOCKDEP is 132 * not enabled. 133 * @lock: One transaction at a time. 134 * @mkbp_event_supported: 0 if MKBP not supported. Otherwise its value is 135 * the maximum supported version of the MKBP host event 136 * command + 1. 137 * @host_sleep_v1: True if this EC supports the sleep v1 command. 138 * @event_notifier: Interrupt event notifier for transport devices. 139 * @event_data: Raw payload transferred with the MKBP event. 140 * @event_size: Size in bytes of the event data. 141 * @host_event_wake_mask: Mask of host events that cause wake from suspend. 142 * @suspend_timeout_ms: The timeout in milliseconds between when sleep event 143 * is received and when the EC will declare sleep 144 * transition failure if the sleep signal is not 145 * asserted. See also struct 146 * ec_params_host_sleep_event_v1 in cros_ec_commands.h. 147 * @last_resume_result: The number of sleep power signal transitions that 148 * occurred since the suspend message. The high bit 149 * indicates a timeout occurred. See also struct 150 * ec_response_host_sleep_event_v1 in cros_ec_commands.h. 151 * @last_event_time: exact time from the hard irq when we got notified of 152 * a new event. 153 * @notifier_ready: The notifier_block to let the kernel re-query EC 154 * communication protocol when the EC sends 155 * EC_HOST_EVENT_INTERFACE_READY. 156 * @ec: The platform_device used by the mfd driver to interface with the 157 * main EC. 158 * @pd: The platform_device used by the mfd driver to interface with the 159 * PD behind an EC. 160 * @panic_notifier: EC panic notifier. 161 */ 162 struct cros_ec_device { 163 /* These are used by other drivers that want to talk to the EC */ 164 const char *phys_name; 165 struct device *dev; 166 struct class *cros_class; 167 int (*cmd_readmem)(struct cros_ec_device *ec, unsigned int offset, 168 unsigned int bytes, void *dest); 169 170 /* These are used to implement the platform-specific interface */ 171 u16 max_request; 172 u16 max_response; 173 u16 max_passthru; 174 u16 proto_version; 175 void *priv; 176 int irq; 177 u8 *din; 178 u8 *dout; 179 int din_size; 180 int dout_size; 181 bool wake_enabled; 182 bool suspended; 183 int (*cmd_xfer)(struct cros_ec_device *ec, 184 struct cros_ec_command *msg); 185 int (*pkt_xfer)(struct cros_ec_device *ec, 186 struct cros_ec_command *msg); 187 struct lock_class_key lockdep_key; 188 struct mutex lock; 189 u8 mkbp_event_supported; 190 bool host_sleep_v1; 191 struct blocking_notifier_head event_notifier; 192 193 struct ec_response_get_next_event_v3 event_data; 194 int event_size; 195 u32 host_event_wake_mask; 196 u32 last_resume_result; 197 u16 suspend_timeout_ms; 198 ktime_t last_event_time; 199 struct notifier_block notifier_ready; 200 201 /* The platform devices used by the mfd driver */ 202 struct platform_device *ec; 203 struct platform_device *pd; 204 205 struct blocking_notifier_head panic_notifier; 206 }; 207 208 /** 209 * struct cros_ec_platform - ChromeOS EC platform information. 210 * @ec_name: Name of EC device (e.g. 'cros-ec', 'cros-pd', ...) 211 * used in /dev/ and sysfs. 212 * @cmd_offset: Offset to apply for each command. Set when 213 * registering a device behind another one. 214 */ 215 struct cros_ec_platform { 216 const char *ec_name; 217 u16 cmd_offset; 218 }; 219 220 /** 221 * struct cros_ec_dev - ChromeOS EC device entry point. 222 * @class_dev: Device structure used in sysfs. 223 * @ec_dev: cros_ec_device structure to talk to the physical device. 224 * @dev: Pointer to the platform device. 225 * @debug_info: cros_ec_debugfs structure for debugging information. 226 * @has_kb_wake_angle: True if at least 2 accelerometer are connected to the EC. 227 * @cmd_offset: Offset to apply for each command. 228 * @features: Features supported by the EC. 229 */ 230 struct cros_ec_dev { 231 struct device class_dev; 232 struct cros_ec_device *ec_dev; 233 struct device *dev; 234 struct cros_ec_debugfs *debug_info; 235 bool has_kb_wake_angle; 236 u16 cmd_offset; 237 struct ec_response_get_features features; 238 }; 239 240 #define to_cros_ec_dev(dev) container_of(dev, struct cros_ec_dev, class_dev) 241 242 int cros_ec_prepare_tx(struct cros_ec_device *ec_dev, 243 struct cros_ec_command *msg); 244 245 int cros_ec_check_result(struct cros_ec_device *ec_dev, 246 struct cros_ec_command *msg); 247 248 int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, 249 struct cros_ec_command *msg); 250 251 int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, 252 struct cros_ec_command *msg); 253 254 int cros_ec_rwsig_continue(struct cros_ec_device *ec_dev); 255 256 int cros_ec_query_all(struct cros_ec_device *ec_dev); 257 258 int cros_ec_get_next_event(struct cros_ec_device *ec_dev, 259 bool *wake_event, 260 bool *has_more_events); 261 262 u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev); 263 264 bool cros_ec_check_features(struct cros_ec_dev *ec, int feature); 265 266 int cros_ec_get_sensor_count(struct cros_ec_dev *ec); 267 268 int cros_ec_cmd(struct cros_ec_device *ec_dev, unsigned int version, int command, const void *outdata, 269 size_t outsize, void *indata, size_t insize); 270 271 int cros_ec_cmd_readmem(struct cros_ec_device *ec_dev, u8 offset, u8 size, void *dest); 272 273 int cros_ec_get_cmd_versions(struct cros_ec_device *ec_dev, u16 cmd); 274 275 /** 276 * cros_ec_get_time_ns() - Return time in ns. 277 * 278 * This is the function used to record the time for last_event_time in struct 279 * cros_ec_device during the hard irq. 280 * 281 * Return: ktime_t format since boot. 282 */ 283 static inline ktime_t cros_ec_get_time_ns(void) 284 { 285 return ktime_get_boottime_ns(); 286 } 287 288 #endif /* __LINUX_CROS_EC_PROTO_H */ 289