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Diffstat (limited to 'include/linux/platform_data/cros_ec_proto.h')
| -rw-r--r-- | include/linux/platform_data/cros_ec_proto.h | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/include/linux/platform_data/cros_ec_proto.h b/include/linux/platform_data/cros_ec_proto.h new file mode 100644 index 000000000..4f9f756bc --- /dev/null +++ b/include/linux/platform_data/cros_ec_proto.h @@ -0,0 +1,277 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * ChromeOS Embedded Controller protocol interface. + * + * Copyright (C) 2012 Google, Inc + */ + +#ifndef __LINUX_CROS_EC_PROTO_H +#define __LINUX_CROS_EC_PROTO_H + +#include <linux/device.h> +#include <linux/lockdep_types.h> +#include <linux/mutex.h> +#include <linux/notifier.h> + +#include <linux/platform_data/cros_ec_commands.h> + +#define CROS_EC_DEV_NAME "cros_ec" +#define CROS_EC_DEV_FP_NAME "cros_fp" +#define CROS_EC_DEV_ISH_NAME "cros_ish" +#define CROS_EC_DEV_PD_NAME "cros_pd" +#define CROS_EC_DEV_SCP_NAME "cros_scp" +#define CROS_EC_DEV_TP_NAME "cros_tp" + +#define CROS_EC_DEV_EC_INDEX 0 +#define CROS_EC_DEV_PD_INDEX 1 + +/* + * The EC is unresponsive for a time after a reboot command. Add a + * simple delay to make sure that the bus stays locked. + */ +#define EC_REBOOT_DELAY_MS 50 + +/* + * Max bus-specific overhead incurred by request/responses. + * I2C requires 1 additional byte for requests. + * I2C requires 2 additional bytes for responses. + * SPI requires up to 32 additional bytes for responses. + */ +#define EC_PROTO_VERSION_UNKNOWN 0 +#define EC_MAX_REQUEST_OVERHEAD 1 +#define EC_MAX_RESPONSE_OVERHEAD 32 + +/* + * EC panic is not covered by the standard (0-F) ACPI notify values. + * Arbitrarily choosing B0 to notify ec panic, which is in the 84-BF + * device specific ACPI notify range. + */ +#define ACPI_NOTIFY_CROS_EC_PANIC 0xB0 + +/* + * Command interface between EC and AP, for LPC, I2C and SPI interfaces. + */ +enum { + EC_MSG_TX_HEADER_BYTES = 3, + EC_MSG_TX_TRAILER_BYTES = 1, + EC_MSG_TX_PROTO_BYTES = EC_MSG_TX_HEADER_BYTES + + EC_MSG_TX_TRAILER_BYTES, + EC_MSG_RX_PROTO_BYTES = 3, + + /* Max length of messages for proto 2*/ + EC_PROTO2_MSG_BYTES = EC_PROTO2_MAX_PARAM_SIZE + + EC_MSG_TX_PROTO_BYTES, + + EC_MAX_MSG_BYTES = 64 * 1024, +}; + +/** + * struct cros_ec_command - Information about a ChromeOS EC command. + * @version: Command version number (often 0). + * @command: Command to send (EC_CMD_...). + * @outsize: Outgoing length in bytes. + * @insize: Max number of bytes to accept from the EC. + * @result: EC's response to the command (separate from communication failure). + * @data: Where to put the incoming data from EC and outgoing data to EC. + */ +struct cros_ec_command { + uint32_t version; + uint32_t command; + uint32_t outsize; + uint32_t insize; + uint32_t result; + uint8_t data[]; +}; + +/** + * struct cros_ec_device - Information about a ChromeOS EC device. + * @phys_name: Name of physical comms layer (e.g. 'i2c-4'). + * @dev: Device pointer for physical comms device + * @cros_class: The class structure for this device. + * @cmd_readmem: Direct read of the EC memory-mapped region, if supported. + * @offset: Is within EC_LPC_ADDR_MEMMAP region. + * @bytes: Number of bytes to read. zero means "read a string" (including + * the trailing '\0'). At most only EC_MEMMAP_SIZE bytes can be + * read. Caller must ensure that the buffer is large enough for the + * result when reading a string. + * @max_request: Max size of message requested. + * @max_response: Max size of message response. + * @max_passthru: Max sice of passthru message. + * @proto_version: The protocol version used for this device. + * @priv: Private data. + * @irq: Interrupt to use. + * @id: Device id. + * @din: Input buffer (for data from EC). This buffer will always be + * dword-aligned and include enough space for up to 7 word-alignment + * bytes also, so we can ensure that the body of the message is always + * dword-aligned (64-bit). We use this alignment to keep ARM and x86 + * happy. Probably word alignment would be OK, there might be a small + * performance advantage to using dword. + * @dout: Output buffer (for data to EC). This buffer will always be + * dword-aligned and include enough space for up to 7 word-alignment + * bytes also, so we can ensure that the body of the message is always + * dword-aligned (64-bit). We use this alignment to keep ARM and x86 + * happy. Probably word alignment would be OK, there might be a small + * performance advantage to using dword. + * @din_size: Size of din buffer to allocate (zero to use static din). + * @dout_size: Size of dout buffer to allocate (zero to use static dout). + * @wake_enabled: True if this device can wake the system from sleep. + * @suspended: True if this device had been suspended. + * @cmd_xfer: Send command to EC and get response. + * Returns the number of bytes received if the communication + * succeeded, but that doesn't mean the EC was happy with the + * command. The caller should check msg.result for the EC's result + * code. + * @pkt_xfer: Send packet to EC and get response. + * @lockdep_key: Lockdep class for each instance. Unused if CONFIG_LOCKDEP is + * not enabled. + * @lock: One transaction at a time. + * @mkbp_event_supported: 0 if MKBP not supported. Otherwise its value is + * the maximum supported version of the MKBP host event + * command + 1. + * @host_sleep_v1: True if this EC supports the sleep v1 command. + * @event_notifier: Interrupt event notifier for transport devices. + * @event_data: Raw payload transferred with the MKBP event. + * @event_size: Size in bytes of the event data. + * @host_event_wake_mask: Mask of host events that cause wake from suspend. + * @suspend_timeout_ms: The timeout in milliseconds between when sleep event + * is received and when the EC will declare sleep + * transition failure if the sleep signal is not + * asserted. See also struct + * ec_params_host_sleep_event_v1 in cros_ec_commands.h. + * @last_resume_result: The number of sleep power signal transitions that + * occurred since the suspend message. The high bit + * indicates a timeout occurred. See also struct + * ec_response_host_sleep_event_v1 in cros_ec_commands.h. + * @last_event_time: exact time from the hard irq when we got notified of + * a new event. + * @notifier_ready: The notifier_block to let the kernel re-query EC + * communication protocol when the EC sends + * EC_HOST_EVENT_INTERFACE_READY. + * @ec: The platform_device used by the mfd driver to interface with the + * main EC. + * @pd: The platform_device used by the mfd driver to interface with the + * PD behind an EC. + * @panic_notifier: EC panic notifier. + */ +struct cros_ec_device { + /* These are used by other drivers that want to talk to the EC */ + const char *phys_name; + struct device *dev; + struct class *cros_class; + int (*cmd_readmem)(struct cros_ec_device *ec, unsigned int offset, + unsigned int bytes, void *dest); + + /* These are used to implement the platform-specific interface */ + u16 max_request; + u16 max_response; + u16 max_passthru; + u16 proto_version; + void *priv; + int irq; + u8 *din; + u8 *dout; + int din_size; + int dout_size; + bool wake_enabled; + bool suspended; + int (*cmd_xfer)(struct cros_ec_device *ec, + struct cros_ec_command *msg); + int (*pkt_xfer)(struct cros_ec_device *ec, + struct cros_ec_command *msg); + struct lock_class_key lockdep_key; + struct mutex lock; + u8 mkbp_event_supported; + bool host_sleep_v1; + struct blocking_notifier_head event_notifier; + + struct ec_response_get_next_event_v1 event_data; + int event_size; + u32 host_event_wake_mask; + u32 last_resume_result; + u16 suspend_timeout_ms; + ktime_t last_event_time; + struct notifier_block notifier_ready; + + /* The platform devices used by the mfd driver */ + struct platform_device *ec; + struct platform_device *pd; + + struct blocking_notifier_head panic_notifier; +}; + +/** + * struct cros_ec_platform - ChromeOS EC platform information. + * @ec_name: Name of EC device (e.g. 'cros-ec', 'cros-pd', ...) + * used in /dev/ and sysfs. + * @cmd_offset: Offset to apply for each command. Set when + * registering a device behind another one. + */ +struct cros_ec_platform { + const char *ec_name; + u16 cmd_offset; +}; + +/** + * struct cros_ec_dev - ChromeOS EC device entry point. + * @class_dev: Device structure used in sysfs. + * @ec_dev: cros_ec_device structure to talk to the physical device. + * @dev: Pointer to the platform device. + * @debug_info: cros_ec_debugfs structure for debugging information. + * @has_kb_wake_angle: True if at least 2 accelerometer are connected to the EC. + * @cmd_offset: Offset to apply for each command. + * @features: Features supported by the EC. + */ +struct cros_ec_dev { + struct device class_dev; + struct cros_ec_device *ec_dev; + struct device *dev; + struct cros_ec_debugfs *debug_info; + bool has_kb_wake_angle; + u16 cmd_offset; + struct ec_response_get_features features; +}; + +#define to_cros_ec_dev(dev) container_of(dev, struct cros_ec_dev, class_dev) + +int cros_ec_prepare_tx(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg); + +int cros_ec_check_result(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg); + +int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg); + +int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev, + struct cros_ec_command *msg); + +int cros_ec_query_all(struct cros_ec_device *ec_dev); + +int cros_ec_get_next_event(struct cros_ec_device *ec_dev, + bool *wake_event, + bool *has_more_events); + +u32 cros_ec_get_host_event(struct cros_ec_device *ec_dev); + +bool cros_ec_check_features(struct cros_ec_dev *ec, int feature); + +int cros_ec_get_sensor_count(struct cros_ec_dev *ec); + +int cros_ec_cmd(struct cros_ec_device *ec_dev, unsigned int version, int command, void *outdata, + size_t outsize, void *indata, size_t insize); + +/** + * cros_ec_get_time_ns() - Return time in ns. + * + * This is the function used to record the time for last_event_time in struct + * cros_ec_device during the hard irq. + * + * Return: ktime_t format since boot. + */ +static inline ktime_t cros_ec_get_time_ns(void) +{ + return ktime_get_boottime_ns(); +} + +#endif /* __LINUX_CROS_EC_PROTO_H */ |