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-rw-r--r--drivers/platform/chrome/wilco_ec/Kconfig20
-rw-r--r--drivers/platform/chrome/wilco_ec/Makefile6
-rw-r--r--drivers/platform/chrome/wilco_ec/core.c136
-rw-r--r--drivers/platform/chrome/wilco_ec/debugfs.c238
-rw-r--r--drivers/platform/chrome/wilco_ec/mailbox.c237
5 files changed, 637 insertions, 0 deletions
diff --git a/drivers/platform/chrome/wilco_ec/Kconfig b/drivers/platform/chrome/wilco_ec/Kconfig
new file mode 100644
index 000000000000..e09e4cebe9b4
--- /dev/null
+++ b/drivers/platform/chrome/wilco_ec/Kconfig
@@ -0,0 +1,20 @@
+config WILCO_EC
+ tristate "ChromeOS Wilco Embedded Controller"
+ depends on ACPI && X86 && CROS_EC_LPC && CROS_EC_LPC_MEC
+ help
+ If you say Y here, you get support for talking to the ChromeOS
+ Wilco EC over an eSPI bus. This uses a simple byte-level protocol
+ with a checksum.
+
+ To compile this driver as a module, choose M here: the
+ module will be called wilco_ec.
+
+config WILCO_EC_DEBUGFS
+ tristate "Enable raw access to EC via debugfs"
+ depends on WILCO_EC
+ help
+ If you say Y here, you get support for sending raw commands to
+ the Wilco EC via debugfs. These commands do not do any byte
+ manipulation and allow for testing arbitrary commands. This
+ interface is intended for debug only and will not be present
+ on production devices.
diff --git a/drivers/platform/chrome/wilco_ec/Makefile b/drivers/platform/chrome/wilco_ec/Makefile
new file mode 100644
index 000000000000..063e7fb4ea17
--- /dev/null
+++ b/drivers/platform/chrome/wilco_ec/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+
+wilco_ec-objs := core.o mailbox.o
+obj-$(CONFIG_WILCO_EC) += wilco_ec.o
+wilco_ec_debugfs-objs := debugfs.o
+obj-$(CONFIG_WILCO_EC_DEBUGFS) += wilco_ec_debugfs.o
diff --git a/drivers/platform/chrome/wilco_ec/core.c b/drivers/platform/chrome/wilco_ec/core.c
new file mode 100644
index 000000000000..05e1e2be1c91
--- /dev/null
+++ b/drivers/platform/chrome/wilco_ec/core.c
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Core driver for Wilco Embedded Controller
+ *
+ * Copyright 2018 Google LLC
+ *
+ * This is the entry point for the drivers that control the Wilco EC.
+ * This driver is responsible for several tasks:
+ * - Initialize the register interface that is used by wilco_ec_mailbox()
+ * - Create a platform device which is picked up by the debugfs driver
+ * - Create a platform device which is picked up by the RTC driver
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_data/wilco-ec.h>
+#include <linux/platform_device.h>
+
+#include "../cros_ec_lpc_mec.h"
+
+#define DRV_NAME "wilco-ec"
+
+static struct resource *wilco_get_resource(struct platform_device *pdev,
+ int index)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, index);
+ if (!res) {
+ dev_dbg(dev, "Couldn't find IO resource %d\n", index);
+ return res;
+ }
+
+ return devm_request_region(dev, res->start, resource_size(res),
+ dev_name(dev));
+}
+
+static int wilco_ec_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct wilco_ec_device *ec;
+ int ret;
+
+ ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
+ if (!ec)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ec);
+ ec->dev = dev;
+ mutex_init(&ec->mailbox_lock);
+
+ /* Largest data buffer size requirement is extended data response */
+ ec->data_size = sizeof(struct wilco_ec_response) +
+ EC_MAILBOX_DATA_SIZE_EXTENDED;
+ ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL);
+ if (!ec->data_buffer)
+ return -ENOMEM;
+
+ /* Prepare access to IO regions provided by ACPI */
+ ec->io_data = wilco_get_resource(pdev, 0); /* Host Data */
+ ec->io_command = wilco_get_resource(pdev, 1); /* Host Command */
+ ec->io_packet = wilco_get_resource(pdev, 2); /* MEC EMI */
+ if (!ec->io_data || !ec->io_command || !ec->io_packet)
+ return -ENODEV;
+
+ /* Initialize cros_ec register interface for communication */
+ cros_ec_lpc_mec_init(ec->io_packet->start,
+ ec->io_packet->start + EC_MAILBOX_DATA_SIZE);
+
+ /*
+ * Register a child device that will be found by the debugfs driver.
+ * Ignore failure.
+ */
+ ec->debugfs_pdev = platform_device_register_data(dev,
+ "wilco-ec-debugfs",
+ PLATFORM_DEVID_AUTO,
+ NULL, 0);
+
+ /* Register a child device that will be found by the RTC driver. */
+ ec->rtc_pdev = platform_device_register_data(dev, "rtc-wilco-ec",
+ PLATFORM_DEVID_AUTO,
+ NULL, 0);
+ if (IS_ERR(ec->rtc_pdev)) {
+ dev_err(dev, "Failed to create RTC platform device\n");
+ ret = PTR_ERR(ec->rtc_pdev);
+ goto unregister_debugfs;
+ }
+
+ return 0;
+
+unregister_debugfs:
+ if (ec->debugfs_pdev)
+ platform_device_unregister(ec->debugfs_pdev);
+ cros_ec_lpc_mec_destroy();
+ return ret;
+}
+
+static int wilco_ec_remove(struct platform_device *pdev)
+{
+ struct wilco_ec_device *ec = platform_get_drvdata(pdev);
+
+ platform_device_unregister(ec->rtc_pdev);
+ if (ec->debugfs_pdev)
+ platform_device_unregister(ec->debugfs_pdev);
+
+ /* Teardown cros_ec interface */
+ cros_ec_lpc_mec_destroy();
+
+ return 0;
+}
+
+static const struct acpi_device_id wilco_ec_acpi_device_ids[] = {
+ { "GOOG000C", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids);
+
+static struct platform_driver wilco_ec_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .acpi_match_table = wilco_ec_acpi_device_ids,
+ },
+ .probe = wilco_ec_probe,
+ .remove = wilco_ec_remove,
+};
+
+module_platform_driver(wilco_ec_driver);
+
+MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
+MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver");
+MODULE_ALIAS("platform:" DRV_NAME);
diff --git a/drivers/platform/chrome/wilco_ec/debugfs.c b/drivers/platform/chrome/wilco_ec/debugfs.c
new file mode 100644
index 000000000000..c090db2cd5be
--- /dev/null
+++ b/drivers/platform/chrome/wilco_ec/debugfs.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * debugfs attributes for Wilco EC
+ *
+ * Copyright 2019 Google LLC
+ *
+ * There is only one attribute used for debugging, called raw.
+ * You can write a hexadecimal sentence to raw, and that series of bytes
+ * will be sent to the EC. Then, you can read the bytes of response
+ * by reading from raw.
+ *
+ * For writing:
+ * Bytes 0-1 indicate the message type:
+ * 00 F0 = Execute Legacy Command
+ * 00 F2 = Read/Write NVRAM Property
+ * Byte 2 provides the command code
+ * Bytes 3+ consist of the data passed in the request
+ *
+ * When referencing the EC interface spec, byte 2 corresponds to MBOX[0],
+ * byte 3 corresponds to MBOX[1], etc.
+ *
+ * At least three bytes are required, for the msg type and command,
+ * with additional bytes optional for additional data.
+ *
+ * Example:
+ * // Request EC info type 3 (EC firmware build date)
+ * $ echo 00 f0 38 00 03 00 > raw
+ * // View the result. The decoded ASCII result "12/21/18" is
+ * // included after the raw hex.
+ * $ cat raw
+ * 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 .12/21/18.8...
+ */
+
+#include <linux/ctype.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/module.h>
+#include <linux/platform_data/wilco-ec.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "wilco-ec-debugfs"
+
+/* The 256 raw bytes will take up more space when represented as a hex string */
+#define FORMATTED_BUFFER_SIZE (EC_MAILBOX_DATA_SIZE_EXTENDED * 4)
+
+struct wilco_ec_debugfs {
+ struct wilco_ec_device *ec;
+ struct dentry *dir;
+ size_t response_size;
+ u8 raw_data[EC_MAILBOX_DATA_SIZE_EXTENDED];
+ u8 formatted_data[FORMATTED_BUFFER_SIZE];
+};
+static struct wilco_ec_debugfs *debug_info;
+
+/**
+ * parse_hex_sentence() - Convert a ascii hex representation into byte array.
+ * @in: Input buffer of ascii.
+ * @isize: Length of input buffer.
+ * @out: Output buffer.
+ * @osize: Length of output buffer, e.g. max number of bytes to parse.
+ *
+ * An valid input is a series of ascii hexadecimal numbers, separated by spaces.
+ * An example valid input is
+ * " 00 f2 0 000076 6 0 ff"
+ *
+ * If an individual "word" within the hex sentence is longer than MAX_WORD_SIZE,
+ * then the sentence is illegal, and parsing will fail.
+ *
+ * Return: Number of bytes parsed, or negative error code on failure.
+ */
+static int parse_hex_sentence(const char *in, int isize, u8 *out, int osize)
+{
+ int n_parsed = 0;
+ int word_start = 0;
+ int word_end;
+ int word_len;
+ /* Temp buffer for holding a "word" of chars that represents one byte */
+ #define MAX_WORD_SIZE 16
+ char tmp[MAX_WORD_SIZE + 1];
+ u8 byte;
+
+ while (word_start < isize && n_parsed < osize) {
+ /* Find the start of the next word */
+ while (word_start < isize && isspace(in[word_start]))
+ word_start++;
+ /* reached the end of the input before next word? */
+ if (word_start >= isize)
+ break;
+
+ /* Find the end of this word */
+ word_end = word_start;
+ while (word_end < isize && !isspace(in[word_end]))
+ word_end++;
+
+ /* Copy to a tmp NULL terminated string */
+ word_len = word_end - word_start;
+ if (word_len > MAX_WORD_SIZE)
+ return -EINVAL;
+ memcpy(tmp, in + word_start, word_len);
+ tmp[word_len] = '\0';
+
+ /*
+ * Convert from hex string, place in output. If fails to parse,
+ * just return -EINVAL because specific error code is only
+ * relevant for this one word, returning it would be confusing.
+ */
+ if (kstrtou8(tmp, 16, &byte))
+ return -EINVAL;
+ out[n_parsed++] = byte;
+
+ word_start = word_end;
+ }
+ return n_parsed;
+}
+
+/* The message type takes up two bytes*/
+#define TYPE_AND_DATA_SIZE ((EC_MAILBOX_DATA_SIZE) + 2)
+
+static ssize_t raw_write(struct file *file, const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ char *buf = debug_info->formatted_data;
+ struct wilco_ec_message msg;
+ u8 request_data[TYPE_AND_DATA_SIZE];
+ ssize_t kcount;
+ int ret;
+
+ if (count > FORMATTED_BUFFER_SIZE)
+ return -EINVAL;
+
+ kcount = simple_write_to_buffer(buf, FORMATTED_BUFFER_SIZE, ppos,
+ user_buf, count);
+ if (kcount < 0)
+ return kcount;
+
+ ret = parse_hex_sentence(buf, kcount, request_data, TYPE_AND_DATA_SIZE);
+ if (ret < 0)
+ return ret;
+ /* Need at least two bytes for message type and one for command */
+ if (ret < 3)
+ return -EINVAL;
+
+ /* Clear response data buffer */
+ memset(debug_info->raw_data, '\0', EC_MAILBOX_DATA_SIZE_EXTENDED);
+
+ msg.type = request_data[0] << 8 | request_data[1];
+ msg.flags = WILCO_EC_FLAG_RAW;
+ msg.command = request_data[2];
+ msg.request_data = ret > 3 ? request_data + 3 : 0;
+ msg.request_size = ret - 3;
+ msg.response_data = debug_info->raw_data;
+ msg.response_size = EC_MAILBOX_DATA_SIZE;
+
+ /* Telemetry commands use extended response data */
+ if (msg.type == WILCO_EC_MSG_TELEMETRY_LONG) {
+ msg.flags |= WILCO_EC_FLAG_EXTENDED_DATA;
+ msg.response_size = EC_MAILBOX_DATA_SIZE_EXTENDED;
+ }
+
+ ret = wilco_ec_mailbox(debug_info->ec, &msg);
+ if (ret < 0)
+ return ret;
+ debug_info->response_size = ret;
+
+ return count;
+}
+
+static ssize_t raw_read(struct file *file, char __user *user_buf, size_t count,
+ loff_t *ppos)
+{
+ int fmt_len = 0;
+
+ if (debug_info->response_size) {
+ fmt_len = hex_dump_to_buffer(debug_info->raw_data,
+ debug_info->response_size,
+ 16, 1, debug_info->formatted_data,
+ FORMATTED_BUFFER_SIZE, true);
+ /* Only return response the first time it is read */
+ debug_info->response_size = 0;
+ }
+
+ return simple_read_from_buffer(user_buf, count, ppos,
+ debug_info->formatted_data, fmt_len);
+}
+
+static const struct file_operations fops_raw = {
+ .owner = THIS_MODULE,
+ .read = raw_read,
+ .write = raw_write,
+ .llseek = no_llseek,
+};
+
+/**
+ * wilco_ec_debugfs_probe() - Create the debugfs node
+ * @pdev: The platform device, probably created in core.c
+ *
+ * Try to create a debugfs node. If it fails, then we don't want to change
+ * behavior at all, this is for debugging after all. Just fail silently.
+ *
+ * Return: 0 always.
+ */
+static int wilco_ec_debugfs_probe(struct platform_device *pdev)
+{
+ struct wilco_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
+
+ debug_info = devm_kzalloc(&pdev->dev, sizeof(*debug_info), GFP_KERNEL);
+ if (!debug_info)
+ return 0;
+ debug_info->ec = ec;
+ debug_info->dir = debugfs_create_dir("wilco_ec", NULL);
+ if (!debug_info->dir)
+ return 0;
+ debugfs_create_file("raw", 0644, debug_info->dir, NULL, &fops_raw);
+
+ return 0;
+}
+
+static int wilco_ec_debugfs_remove(struct platform_device *pdev)
+{
+ debugfs_remove_recursive(debug_info->dir);
+
+ return 0;
+}
+
+static struct platform_driver wilco_ec_debugfs_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ },
+ .probe = wilco_ec_debugfs_probe,
+ .remove = wilco_ec_debugfs_remove,
+};
+
+module_platform_driver(wilco_ec_debugfs_driver);
+
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Wilco EC debugfs driver");
diff --git a/drivers/platform/chrome/wilco_ec/mailbox.c b/drivers/platform/chrome/wilco_ec/mailbox.c
new file mode 100644
index 000000000000..f6ff29a11f1a
--- /dev/null
+++ b/drivers/platform/chrome/wilco_ec/mailbox.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Mailbox interface for Wilco Embedded Controller
+ *
+ * Copyright 2018 Google LLC
+ *
+ * The Wilco EC is similar to a typical ChromeOS embedded controller.
+ * It uses the same MEC based low-level communication and a similar
+ * protocol, but with some important differences. The EC firmware does
+ * not support the same mailbox commands so it is not registered as a
+ * cros_ec device type.
+ *
+ * Most messages follow a standard format, but there are some exceptions
+ * and an interface is provided to do direct/raw transactions that do not
+ * make assumptions about byte placement.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/platform_data/wilco-ec.h>
+#include <linux/platform_device.h>
+
+#include "../cros_ec_lpc_mec.h"
+
+/* Version of mailbox interface */
+#define EC_MAILBOX_VERSION 0
+
+/* Command to start mailbox transaction */
+#define EC_MAILBOX_START_COMMAND 0xda
+
+/* Version of EC protocol */
+#define EC_MAILBOX_PROTO_VERSION 3
+
+/* Number of header bytes to be counted as data bytes */
+#define EC_MAILBOX_DATA_EXTRA 2
+
+/* Maximum timeout */
+#define EC_MAILBOX_TIMEOUT HZ
+
+/* EC response flags */
+#define EC_CMDR_DATA BIT(0) /* Data ready for host to read */
+#define EC_CMDR_PENDING BIT(1) /* Write pending to EC */
+#define EC_CMDR_BUSY BIT(2) /* EC is busy processing a command */
+#define EC_CMDR_CMD BIT(3) /* Last host write was a command */
+
+/**
+ * wilco_ec_response_timed_out() - Wait for EC response.
+ * @ec: EC device.
+ *
+ * Return: true if EC timed out, false if EC did not time out.
+ */
+static bool wilco_ec_response_timed_out(struct wilco_ec_device *ec)
+{
+ unsigned long timeout = jiffies + EC_MAILBOX_TIMEOUT;
+
+ do {
+ if (!(inb(ec->io_command->start) &
+ (EC_CMDR_PENDING | EC_CMDR_BUSY)))
+ return false;
+ usleep_range(100, 200);
+ } while (time_before(jiffies, timeout));
+
+ return true;
+}
+
+/**
+ * wilco_ec_checksum() - Compute 8-bit checksum over data range.
+ * @data: Data to checksum.
+ * @size: Number of bytes to checksum.
+ *
+ * Return: 8-bit checksum of provided data.
+ */
+static u8 wilco_ec_checksum(const void *data, size_t size)
+{
+ u8 *data_bytes = (u8 *)data;
+ u8 checksum = 0;
+ size_t i;
+
+ for (i = 0; i < size; i++)
+ checksum += data_bytes[i];
+
+ return checksum;
+}
+
+/**
+ * wilco_ec_prepare() - Prepare the request structure for the EC.
+ * @msg: EC message with request information.
+ * @rq: EC request structure to fill.
+ */
+static void wilco_ec_prepare(struct wilco_ec_message *msg,
+ struct wilco_ec_request *rq)
+{
+ memset(rq, 0, sizeof(*rq));
+
+ /* Handle messages without trimming bytes from the request */
+ if (msg->request_size && msg->flags & WILCO_EC_FLAG_RAW_REQUEST) {
+ rq->reserved_raw = *(u8 *)msg->request_data;
+ msg->request_size--;
+ memmove(msg->request_data, msg->request_data + 1,
+ msg->request_size);
+ }
+
+ /* Fill in request packet */
+ rq->struct_version = EC_MAILBOX_PROTO_VERSION;
+ rq->mailbox_id = msg->type;
+ rq->mailbox_version = EC_MAILBOX_VERSION;
+ rq->data_size = msg->request_size + EC_MAILBOX_DATA_EXTRA;
+ rq->command = msg->command;
+
+ /* Checksum header and data */
+ rq->checksum = wilco_ec_checksum(rq, sizeof(*rq));
+ rq->checksum += wilco_ec_checksum(msg->request_data, msg->request_size);
+ rq->checksum = -rq->checksum;
+}
+
+/**
+ * wilco_ec_transfer() - Perform actual data transfer.
+ * @ec: EC device.
+ * @msg: EC message data for request and response.
+ * @rq: Filled in request structure
+ *
+ * Context: ec->mailbox_lock should be held while using this function.
+ * Return: number of bytes received or negative error code on failure.
+ */
+static int wilco_ec_transfer(struct wilco_ec_device *ec,
+ struct wilco_ec_message *msg,
+ struct wilco_ec_request *rq)
+{
+ struct wilco_ec_response *rs;
+ u8 checksum;
+ u8 flag;
+ size_t size;
+
+ /* Write request header, then data */
+ cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, 0, sizeof(*rq), (u8 *)rq);
+ cros_ec_lpc_io_bytes_mec(MEC_IO_WRITE, sizeof(*rq), msg->request_size,
+ msg->request_data);
+
+ /* Start the command */
+ outb(EC_MAILBOX_START_COMMAND, ec->io_command->start);
+
+ /* For some commands (eg shutdown) the EC will not respond, that's OK */
+ if (msg->flags & WILCO_EC_FLAG_NO_RESPONSE) {
+ dev_dbg(ec->dev, "EC does not respond to this command\n");
+ return 0;
+ }
+
+ /* Wait for it to complete */
+ if (wilco_ec_response_timed_out(ec)) {
+ dev_dbg(ec->dev, "response timed out\n");
+ return -ETIMEDOUT;
+ }
+
+ /* Check result */
+ flag = inb(ec->io_data->start);
+ if (flag) {
+ dev_dbg(ec->dev, "bad response: 0x%02x\n", flag);
+ return -EIO;
+ }
+
+ if (msg->flags & WILCO_EC_FLAG_EXTENDED_DATA)
+ size = EC_MAILBOX_DATA_SIZE_EXTENDED;
+ else
+ size = EC_MAILBOX_DATA_SIZE;
+
+ /* Read back response */
+ rs = ec->data_buffer;
+ checksum = cros_ec_lpc_io_bytes_mec(MEC_IO_READ, 0,
+ sizeof(*rs) + size, (u8 *)rs);
+ if (checksum) {
+ dev_dbg(ec->dev, "bad packet checksum 0x%02x\n", rs->checksum);
+ return -EBADMSG;
+ }
+
+ /* Check that the EC reported success */
+ msg->result = rs->result;
+ if (msg->result) {
+ dev_dbg(ec->dev, "bad response: 0x%02x\n", msg->result);
+ return -EBADMSG;
+ }
+
+ /* Check the returned data size, skipping the header */
+ if (rs->data_size != size) {
+ dev_dbg(ec->dev, "unexpected packet size (%u != %zu)",
+ rs->data_size, size);
+ return -EMSGSIZE;
+ }
+
+ /* Skip 1 response data byte unless specified */
+ size = (msg->flags & WILCO_EC_FLAG_RAW_RESPONSE) ? 0 : 1;
+ if ((ssize_t) rs->data_size - size < msg->response_size) {
+ dev_dbg(ec->dev, "response data too short (%zd < %zu)",
+ (ssize_t) rs->data_size - size, msg->response_size);
+ return -EMSGSIZE;
+ }
+
+ /* Ignore response data bytes as requested */
+ memcpy(msg->response_data, rs->data + size, msg->response_size);
+
+ /* Return actual amount of data received */
+ return msg->response_size;
+}
+
+/**
+ * wilco_ec_mailbox() - Send EC request and receive EC response.
+ * @ec: EC device.
+ * @msg: EC message data for request and response.
+ *
+ * On entry msg->type, msg->flags, msg->command, msg->request_size,
+ * msg->response_size, and msg->request_data should all be filled in.
+ *
+ * On exit msg->result and msg->response_data will be filled.
+ *
+ * Return: number of bytes received or negative error code on failure.
+ */
+int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg)
+{
+ struct wilco_ec_request *rq;
+ int ret;
+
+ dev_dbg(ec->dev, "cmd=%02x type=%04x flags=%02x rslen=%zu rqlen=%zu\n",
+ msg->command, msg->type, msg->flags, msg->response_size,
+ msg->request_size);
+
+ /* Prepare request packet */
+ rq = ec->data_buffer;
+ wilco_ec_prepare(msg, rq);
+
+ mutex_lock(&ec->mailbox_lock);
+ ret = wilco_ec_transfer(ec, msg, rq);
+ mutex_unlock(&ec->mailbox_lock);
+
+ return ret;
+
+}
+EXPORT_SYMBOL_GPL(wilco_ec_mailbox);