+int cros_ec_i2c_tunnel(struct udevice *dev, struct i2c_msg *in, int nmsgs)
+{
+ struct cros_ec_dev *cdev = dev_get_uclass_priv(dev);
+ union {
+ struct ec_params_i2c_passthru p;
+ uint8_t outbuf[EC_PROTO2_MAX_PARAM_SIZE];
+ } params;
+ union {
+ struct ec_response_i2c_passthru r;
+ uint8_t inbuf[EC_PROTO2_MAX_PARAM_SIZE];
+ } response;
+ struct ec_params_i2c_passthru *p = ¶ms.p;
+ struct ec_response_i2c_passthru *r = &response.r;
+ struct ec_params_i2c_passthru_msg *msg;
+ uint8_t *pdata, *read_ptr = NULL;
+ int read_len;
+ int size;
+ int rv;
+ int i;
+
+ p->port = 0;
+
+ p->num_msgs = nmsgs;
+ size = sizeof(*p) + p->num_msgs * sizeof(*msg);
+
+ /* Create a message to write the register address and optional data */
+ pdata = (uint8_t *)p + size;
+
+ read_len = 0;
+ for (i = 0, msg = p->msg; i < nmsgs; i++, msg++, in++) {
+ bool is_read = in->flags & I2C_M_RD;
+
+ msg->addr_flags = in->addr;
+ msg->len = in->len;
+ if (is_read) {
+ msg->addr_flags |= EC_I2C_FLAG_READ;
+ read_len += in->len;
+ read_ptr = in->buf;
+ if (sizeof(*r) + read_len > sizeof(response)) {
+ puts("Read length too big for buffer\n");
+ return -1;
+ }
+ } else {
+ if (pdata - (uint8_t *)p + in->len > sizeof(params)) {
+ puts("Params too large for buffer\n");
+ return -1;
+ }
+ memcpy(pdata, in->buf, in->len);
+ pdata += in->len;
+ }
+ }
+
+ rv = ec_command(cdev, EC_CMD_I2C_PASSTHRU, 0, p, pdata - (uint8_t *)p,
+ r, sizeof(*r) + read_len);
+ if (rv < 0)
+ return rv;
+
+ /* Parse response */
+ if (r->i2c_status & EC_I2C_STATUS_ERROR) {
+ printf("Transfer failed with status=0x%x\n", r->i2c_status);
+ return -1;
+ }
+
+ if (rv < sizeof(*r) + read_len) {
+ puts("Truncated read response\n");
+ return -1;
+ }
+
+ /* We only support a single read message for each transfer */
+ if (read_len)
+ memcpy(read_ptr, r->data, read_len);
+
+ return 0;
+}
+