Add qemu 2.4.0
[kvmfornfv.git] / qemu / roms / u-boot / drivers / misc / cros_ec.c
diff --git a/qemu/roms/u-boot/drivers/misc/cros_ec.c b/qemu/roms/u-boot/drivers/misc/cros_ec.c
new file mode 100644 (file)
index 0000000..068373b
--- /dev/null
@@ -0,0 +1,1796 @@
+/*
+ * Chromium OS cros_ec driver
+ *
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+/*
+ * This is the interface to the Chrome OS EC. It provides keyboard functions,
+ * power control and battery management. Quite a few other functions are
+ * provided to enable the EC software to be updated, talk to the EC's I2C bus
+ * and store a small amount of data in a memory which persists while the EC
+ * is not reset.
+ */
+
+#include <common.h>
+#include <command.h>
+#include <i2c.h>
+#include <cros_ec.h>
+#include <fdtdec.h>
+#include <malloc.h>
+#include <spi.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm-generic/gpio.h>
+
+#ifdef DEBUG_TRACE
+#define debug_trace(fmt, b...) debug(fmt, #b)
+#else
+#define debug_trace(fmt, b...)
+#endif
+
+enum {
+       /* Timeout waiting for a flash erase command to complete */
+       CROS_EC_CMD_TIMEOUT_MS  = 5000,
+       /* Timeout waiting for a synchronous hash to be recomputed */
+       CROS_EC_CMD_HASH_TIMEOUT_MS = 2000,
+};
+
+static struct cros_ec_dev static_dev, *last_dev;
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Note: depends on enum ec_current_image */
+static const char * const ec_current_image_name[] = {"unknown", "RO", "RW"};
+
+void cros_ec_dump_data(const char *name, int cmd, const uint8_t *data, int len)
+{
+#ifdef DEBUG
+       int i;
+
+       printf("%s: ", name);
+       if (cmd != -1)
+               printf("cmd=%#x: ", cmd);
+       for (i = 0; i < len; i++)
+               printf("%02x ", data[i]);
+       printf("\n");
+#endif
+}
+
+/*
+ * Calculate a simple 8-bit checksum of a data block
+ *
+ * @param data Data block to checksum
+ * @param size Size of data block in bytes
+ * @return checksum value (0 to 255)
+ */
+int cros_ec_calc_checksum(const uint8_t *data, int size)
+{
+       int csum, i;
+
+       for (i = csum = 0; i < size; i++)
+               csum += data[i];
+       return csum & 0xff;
+}
+
+/**
+ * Create a request packet for protocol version 3.
+ *
+ * The packet is stored in the device's internal output buffer.
+ *
+ * @param dev          CROS-EC device
+ * @param cmd          Command to send (EC_CMD_...)
+ * @param cmd_version  Version of command to send (EC_VER_...)
+ * @param dout          Output data (may be NULL If dout_len=0)
+ * @param dout_len      Size of output data in bytes
+ * @return packet size in bytes, or <0 if error.
+ */
+static int create_proto3_request(struct cros_ec_dev *dev,
+                                int cmd, int cmd_version,
+                                const void *dout, int dout_len)
+{
+       struct ec_host_request *rq = (struct ec_host_request *)dev->dout;
+       int out_bytes = dout_len + sizeof(*rq);
+
+       /* Fail if output size is too big */
+       if (out_bytes > (int)sizeof(dev->dout)) {
+               debug("%s: Cannot send %d bytes\n", __func__, dout_len);
+               return -EC_RES_REQUEST_TRUNCATED;
+       }
+
+       /* Fill in request packet */
+       rq->struct_version = EC_HOST_REQUEST_VERSION;
+       rq->checksum = 0;
+       rq->command = cmd;
+       rq->command_version = cmd_version;
+       rq->reserved = 0;
+       rq->data_len = dout_len;
+
+       /* Copy data after header */
+       memcpy(rq + 1, dout, dout_len);
+
+       /* Write checksum field so the entire packet sums to 0 */
+       rq->checksum = (uint8_t)(-cros_ec_calc_checksum(dev->dout, out_bytes));
+
+       cros_ec_dump_data("out", cmd, dev->dout, out_bytes);
+
+       /* Return size of request packet */
+       return out_bytes;
+}
+
+/**
+ * Prepare the device to receive a protocol version 3 response.
+ *
+ * @param dev          CROS-EC device
+ * @param din_len       Maximum size of response in bytes
+ * @return maximum expected number of bytes in response, or <0 if error.
+ */
+static int prepare_proto3_response_buffer(struct cros_ec_dev *dev, int din_len)
+{
+       int in_bytes = din_len + sizeof(struct ec_host_response);
+
+       /* Fail if input size is too big */
+       if (in_bytes > (int)sizeof(dev->din)) {
+               debug("%s: Cannot receive %d bytes\n", __func__, din_len);
+               return -EC_RES_RESPONSE_TOO_BIG;
+       }
+
+       /* Return expected size of response packet */
+       return in_bytes;
+}
+
+/**
+ * Handle a protocol version 3 response packet.
+ *
+ * The packet must already be stored in the device's internal input buffer.
+ *
+ * @param dev          CROS-EC device
+ * @param dinp          Returns pointer to response data
+ * @param din_len       Maximum size of response in bytes
+ * @return number of bytes of response data, or <0 if error
+ */
+static int handle_proto3_response(struct cros_ec_dev *dev,
+                                 uint8_t **dinp, int din_len)
+{
+       struct ec_host_response *rs = (struct ec_host_response *)dev->din;
+       int in_bytes;
+       int csum;
+
+       cros_ec_dump_data("in-header", -1, dev->din, sizeof(*rs));
+
+       /* Check input data */
+       if (rs->struct_version != EC_HOST_RESPONSE_VERSION) {
+               debug("%s: EC response version mismatch\n", __func__);
+               return -EC_RES_INVALID_RESPONSE;
+       }
+
+       if (rs->reserved) {
+               debug("%s: EC response reserved != 0\n", __func__);
+               return -EC_RES_INVALID_RESPONSE;
+       }
+
+       if (rs->data_len > din_len) {
+               debug("%s: EC returned too much data\n", __func__);
+               return -EC_RES_RESPONSE_TOO_BIG;
+       }
+
+       cros_ec_dump_data("in-data", -1, dev->din + sizeof(*rs), rs->data_len);
+
+       /* Update in_bytes to actual data size */
+       in_bytes = sizeof(*rs) + rs->data_len;
+
+       /* Verify checksum */
+       csum = cros_ec_calc_checksum(dev->din, in_bytes);
+       if (csum) {
+               debug("%s: EC response checksum invalid: 0x%02x\n", __func__,
+                     csum);
+               return -EC_RES_INVALID_CHECKSUM;
+       }
+
+       /* Return error result, if any */
+       if (rs->result)
+               return -(int)rs->result;
+
+       /* If we're still here, set response data pointer and return length */
+       *dinp = (uint8_t *)(rs + 1);
+
+       return rs->data_len;
+}
+
+static int send_command_proto3(struct cros_ec_dev *dev,
+                              int cmd, int cmd_version,
+                              const void *dout, int dout_len,
+                              uint8_t **dinp, int din_len)
+{
+       int out_bytes, in_bytes;
+       int rv;
+
+       /* Create request packet */
+       out_bytes = create_proto3_request(dev, cmd, cmd_version,
+                                         dout, dout_len);
+       if (out_bytes < 0)
+               return out_bytes;
+
+       /* Prepare response buffer */
+       in_bytes = prepare_proto3_response_buffer(dev, din_len);
+       if (in_bytes < 0)
+               return in_bytes;
+
+       switch (dev->interface) {
+#ifdef CONFIG_CROS_EC_SPI
+       case CROS_EC_IF_SPI:
+               rv = cros_ec_spi_packet(dev, out_bytes, in_bytes);
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_SANDBOX
+       case CROS_EC_IF_SANDBOX:
+               rv = cros_ec_sandbox_packet(dev, out_bytes, in_bytes);
+               break;
+#endif
+       case CROS_EC_IF_NONE:
+       /* TODO: support protocol 3 for LPC, I2C; for now fall through */
+       default:
+               debug("%s: Unsupported interface\n", __func__);
+               rv = -1;
+       }
+       if (rv < 0)
+               return rv;
+
+       /* Process the response */
+       return handle_proto3_response(dev, dinp, din_len);
+}
+
+static int send_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
+                       const void *dout, int dout_len,
+                       uint8_t **dinp, int din_len)
+{
+       int ret = -1;
+
+       /* Handle protocol version 3 support */
+       if (dev->protocol_version == 3) {
+               return send_command_proto3(dev, cmd, cmd_version,
+                                          dout, dout_len, dinp, din_len);
+       }
+
+       switch (dev->interface) {
+#ifdef CONFIG_CROS_EC_SPI
+       case CROS_EC_IF_SPI:
+               ret = cros_ec_spi_command(dev, cmd, cmd_version,
+                                       (const uint8_t *)dout, dout_len,
+                                       dinp, din_len);
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_I2C
+       case CROS_EC_IF_I2C:
+               ret = cros_ec_i2c_command(dev, cmd, cmd_version,
+                                       (const uint8_t *)dout, dout_len,
+                                       dinp, din_len);
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_LPC
+       case CROS_EC_IF_LPC:
+               ret = cros_ec_lpc_command(dev, cmd, cmd_version,
+                                       (const uint8_t *)dout, dout_len,
+                                       dinp, din_len);
+               break;
+#endif
+       case CROS_EC_IF_NONE:
+       default:
+               ret = -1;
+       }
+
+       return ret;
+}
+
+/**
+ * Send a command to the CROS-EC device and return the reply.
+ *
+ * The device's internal input/output buffers are used.
+ *
+ * @param dev          CROS-EC device
+ * @param cmd          Command to send (EC_CMD_...)
+ * @param cmd_version  Version of command to send (EC_VER_...)
+ * @param dout          Output data (may be NULL If dout_len=0)
+ * @param dout_len      Size of output data in bytes
+ * @param dinp          Response data (may be NULL If din_len=0).
+ *                     If not NULL, it will be updated to point to the data
+ *                     and will always be double word aligned (64-bits)
+ * @param din_len       Maximum size of response in bytes
+ * @return number of bytes in response, or -1 on error
+ */
+static int ec_command_inptr(struct cros_ec_dev *dev, uint8_t cmd,
+               int cmd_version, const void *dout, int dout_len, uint8_t **dinp,
+               int din_len)
+{
+       uint8_t *din = NULL;
+       int len;
+
+       len = send_command(dev, cmd, cmd_version, dout, dout_len,
+                               &din, din_len);
+
+       /* If the command doesn't complete, wait a while */
+       if (len == -EC_RES_IN_PROGRESS) {
+               struct ec_response_get_comms_status *resp = NULL;
+               ulong start;
+
+               /* Wait for command to complete */
+               start = get_timer(0);
+               do {
+                       int ret;
+
+                       mdelay(50);     /* Insert some reasonable delay */
+                       ret = send_command(dev, EC_CMD_GET_COMMS_STATUS, 0,
+                                       NULL, 0,
+                                       (uint8_t **)&resp, sizeof(*resp));
+                       if (ret < 0)
+                               return ret;
+
+                       if (get_timer(start) > CROS_EC_CMD_TIMEOUT_MS) {
+                               debug("%s: Command %#02x timeout\n",
+                                     __func__, cmd);
+                               return -EC_RES_TIMEOUT;
+                       }
+               } while (resp->flags & EC_COMMS_STATUS_PROCESSING);
+
+               /* OK it completed, so read the status response */
+               /* not sure why it was 0 for the last argument */
+               len = send_command(dev, EC_CMD_RESEND_RESPONSE, 0,
+                               NULL, 0, &din, din_len);
+       }
+
+       debug("%s: len=%d, dinp=%p, *dinp=%p\n", __func__, len, dinp,
+             dinp ? *dinp : NULL);
+       if (dinp) {
+               /* If we have any data to return, it must be 64bit-aligned */
+               assert(len <= 0 || !((uintptr_t)din & 7));
+               *dinp = din;
+       }
+
+       return len;
+}
+
+/**
+ * Send a command to the CROS-EC device and return the reply.
+ *
+ * The device's internal input/output buffers are used.
+ *
+ * @param dev          CROS-EC device
+ * @param cmd          Command to send (EC_CMD_...)
+ * @param cmd_version  Version of command to send (EC_VER_...)
+ * @param dout          Output data (may be NULL If dout_len=0)
+ * @param dout_len      Size of output data in bytes
+ * @param din           Response data (may be NULL If din_len=0).
+ *                     It not NULL, it is a place for ec_command() to copy the
+ *      data to.
+ * @param din_len       Maximum size of response in bytes
+ * @return number of bytes in response, or -1 on error
+ */
+static int ec_command(struct cros_ec_dev *dev, uint8_t cmd, int cmd_version,
+                     const void *dout, int dout_len,
+                     void *din, int din_len)
+{
+       uint8_t *in_buffer;
+       int len;
+
+       assert((din_len == 0) || din);
+       len = ec_command_inptr(dev, cmd, cmd_version, dout, dout_len,
+                       &in_buffer, din_len);
+       if (len > 0) {
+               /*
+                * If we were asked to put it somewhere, do so, otherwise just
+                * disregard the result.
+                */
+               if (din && in_buffer) {
+                       assert(len <= din_len);
+                       memmove(din, in_buffer, len);
+               }
+       }
+       return len;
+}
+
+int cros_ec_scan_keyboard(struct cros_ec_dev *dev, struct mbkp_keyscan *scan)
+{
+       if (ec_command(dev, EC_CMD_MKBP_STATE, 0, NULL, 0, scan,
+                      sizeof(scan->data)) != sizeof(scan->data))
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_read_id(struct cros_ec_dev *dev, char *id, int maxlen)
+{
+       struct ec_response_get_version *r;
+
+       if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
+                       (uint8_t **)&r, sizeof(*r)) != sizeof(*r))
+               return -1;
+
+       if (maxlen > (int)sizeof(r->version_string_ro))
+               maxlen = sizeof(r->version_string_ro);
+
+       switch (r->current_image) {
+       case EC_IMAGE_RO:
+               memcpy(id, r->version_string_ro, maxlen);
+               break;
+       case EC_IMAGE_RW:
+               memcpy(id, r->version_string_rw, maxlen);
+               break;
+       default:
+               return -1;
+       }
+
+       id[maxlen - 1] = '\0';
+       return 0;
+}
+
+int cros_ec_read_version(struct cros_ec_dev *dev,
+                      struct ec_response_get_version **versionp)
+{
+       if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
+                       (uint8_t **)versionp, sizeof(**versionp))
+                       != sizeof(**versionp))
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_read_build_info(struct cros_ec_dev *dev, char **strp)
+{
+       if (ec_command_inptr(dev, EC_CMD_GET_BUILD_INFO, 0, NULL, 0,
+                       (uint8_t **)strp, EC_PROTO2_MAX_PARAM_SIZE) < 0)
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_read_current_image(struct cros_ec_dev *dev,
+               enum ec_current_image *image)
+{
+       struct ec_response_get_version *r;
+
+       if (ec_command_inptr(dev, EC_CMD_GET_VERSION, 0, NULL, 0,
+                       (uint8_t **)&r, sizeof(*r)) != sizeof(*r))
+               return -1;
+
+       *image = r->current_image;
+       return 0;
+}
+
+static int cros_ec_wait_on_hash_done(struct cros_ec_dev *dev,
+                                 struct ec_response_vboot_hash *hash)
+{
+       struct ec_params_vboot_hash p;
+       ulong start;
+
+       start = get_timer(0);
+       while (hash->status == EC_VBOOT_HASH_STATUS_BUSY) {
+               mdelay(50);     /* Insert some reasonable delay */
+
+               p.cmd = EC_VBOOT_HASH_GET;
+               if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
+                      hash, sizeof(*hash)) < 0)
+                       return -1;
+
+               if (get_timer(start) > CROS_EC_CMD_HASH_TIMEOUT_MS) {
+                       debug("%s: EC_VBOOT_HASH_GET timeout\n", __func__);
+                       return -EC_RES_TIMEOUT;
+               }
+       }
+       return 0;
+}
+
+
+int cros_ec_read_hash(struct cros_ec_dev *dev,
+               struct ec_response_vboot_hash *hash)
+{
+       struct ec_params_vboot_hash p;
+       int rv;
+
+       p.cmd = EC_VBOOT_HASH_GET;
+       if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
+                      hash, sizeof(*hash)) < 0)
+               return -1;
+
+       /* If the EC is busy calculating the hash, fidget until it's done. */
+       rv = cros_ec_wait_on_hash_done(dev, hash);
+       if (rv)
+               return rv;
+
+       /* If the hash is valid, we're done. Otherwise, we have to kick it off
+        * again and wait for it to complete. Note that we explicitly assume
+        * that hashing zero bytes is always wrong, even though that would
+        * produce a valid hash value. */
+       if (hash->status == EC_VBOOT_HASH_STATUS_DONE && hash->size)
+               return 0;
+
+       debug("%s: No valid hash (status=%d size=%d). Compute one...\n",
+             __func__, hash->status, hash->size);
+
+       p.cmd = EC_VBOOT_HASH_START;
+       p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
+       p.nonce_size = 0;
+       p.offset = EC_VBOOT_HASH_OFFSET_RW;
+
+       if (ec_command(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
+                      hash, sizeof(*hash)) < 0)
+               return -1;
+
+       rv = cros_ec_wait_on_hash_done(dev, hash);
+       if (rv)
+               return rv;
+
+       debug("%s: hash done\n", __func__);
+
+       return 0;
+}
+
+static int cros_ec_invalidate_hash(struct cros_ec_dev *dev)
+{
+       struct ec_params_vboot_hash p;
+       struct ec_response_vboot_hash *hash;
+
+       /* We don't have an explict command for the EC to discard its current
+        * hash value, so we'll just tell it to calculate one that we know is
+        * wrong (we claim that hashing zero bytes is always invalid).
+        */
+       p.cmd = EC_VBOOT_HASH_RECALC;
+       p.hash_type = EC_VBOOT_HASH_TYPE_SHA256;
+       p.nonce_size = 0;
+       p.offset = 0;
+       p.size = 0;
+
+       debug("%s:\n", __func__);
+
+       if (ec_command_inptr(dev, EC_CMD_VBOOT_HASH, 0, &p, sizeof(p),
+                      (uint8_t **)&hash, sizeof(*hash)) < 0)
+               return -1;
+
+       /* No need to wait for it to finish */
+       return 0;
+}
+
+int cros_ec_reboot(struct cros_ec_dev *dev, enum ec_reboot_cmd cmd,
+               uint8_t flags)
+{
+       struct ec_params_reboot_ec p;
+
+       p.cmd = cmd;
+       p.flags = flags;
+
+       if (ec_command_inptr(dev, EC_CMD_REBOOT_EC, 0, &p, sizeof(p), NULL, 0)
+                       < 0)
+               return -1;
+
+       if (!(flags & EC_REBOOT_FLAG_ON_AP_SHUTDOWN)) {
+               /*
+                * EC reboot will take place immediately so delay to allow it
+                * to complete.  Note that some reboot types (EC_REBOOT_COLD)
+                * will reboot the AP as well, in which case we won't actually
+                * get to this point.
+                */
+               /*
+                * TODO(rspangler@chromium.org): Would be nice if we had a
+                * better way to determine when the reboot is complete.  Could
+                * we poll a memory-mapped LPC value?
+                */
+               udelay(50000);
+       }
+
+       return 0;
+}
+
+int cros_ec_interrupt_pending(struct cros_ec_dev *dev)
+{
+       /* no interrupt support : always poll */
+       if (!fdt_gpio_isvalid(&dev->ec_int))
+               return -ENOENT;
+
+       return !gpio_get_value(dev->ec_int.gpio);
+}
+
+int cros_ec_info(struct cros_ec_dev *dev, struct ec_response_mkbp_info *info)
+{
+       if (ec_command(dev, EC_CMD_MKBP_INFO, 0, NULL, 0, info,
+                      sizeof(*info)) != sizeof(*info))
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_get_host_events(struct cros_ec_dev *dev, uint32_t *events_ptr)
+{
+       struct ec_response_host_event_mask *resp;
+
+       /*
+        * Use the B copy of the event flags, because the main copy is already
+        * used by ACPI/SMI.
+        */
+       if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_GET_B, 0, NULL, 0,
+                      (uint8_t **)&resp, sizeof(*resp)) < (int)sizeof(*resp))
+               return -1;
+
+       if (resp->mask & EC_HOST_EVENT_MASK(EC_HOST_EVENT_INVALID))
+               return -1;
+
+       *events_ptr = resp->mask;
+       return 0;
+}
+
+int cros_ec_clear_host_events(struct cros_ec_dev *dev, uint32_t events)
+{
+       struct ec_params_host_event_mask params;
+
+       params.mask = events;
+
+       /*
+        * Use the B copy of the event flags, so it affects the data returned
+        * by cros_ec_get_host_events().
+        */
+       if (ec_command_inptr(dev, EC_CMD_HOST_EVENT_CLEAR_B, 0,
+                      &params, sizeof(params), NULL, 0) < 0)
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_flash_protect(struct cros_ec_dev *dev,
+                      uint32_t set_mask, uint32_t set_flags,
+                      struct ec_response_flash_protect *resp)
+{
+       struct ec_params_flash_protect params;
+
+       params.mask = set_mask;
+       params.flags = set_flags;
+
+       if (ec_command(dev, EC_CMD_FLASH_PROTECT, EC_VER_FLASH_PROTECT,
+                      &params, sizeof(params),
+                      resp, sizeof(*resp)) != sizeof(*resp))
+               return -1;
+
+       return 0;
+}
+
+static int cros_ec_check_version(struct cros_ec_dev *dev)
+{
+       struct ec_params_hello req;
+       struct ec_response_hello *resp;
+
+#ifdef CONFIG_CROS_EC_LPC
+       /* LPC has its own way of doing this */
+       if (dev->interface == CROS_EC_IF_LPC)
+               return cros_ec_lpc_check_version(dev);
+#endif
+
+       /*
+        * TODO(sjg@chromium.org).
+        * There is a strange oddity here with the EC. We could just ignore
+        * the response, i.e. pass the last two parameters as NULL and 0.
+        * In this case we won't read back very many bytes from the EC.
+        * On the I2C bus the EC gets upset about this and will try to send
+        * the bytes anyway. This means that we will have to wait for that
+        * to complete before continuing with a new EC command.
+        *
+        * This problem is probably unique to the I2C bus.
+        *
+        * So for now, just read all the data anyway.
+        */
+
+       /* Try sending a version 3 packet */
+       dev->protocol_version = 3;
+       if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
+                            (uint8_t **)&resp, sizeof(*resp)) > 0) {
+               return 0;
+       }
+
+       /* Try sending a version 2 packet */
+       dev->protocol_version = 2;
+       if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
+                      (uint8_t **)&resp, sizeof(*resp)) > 0) {
+               return 0;
+       }
+
+       /*
+        * Fail if we're still here, since the EC doesn't understand any
+        * protcol version we speak.  Version 1 interface without command
+        * version is no longer supported, and we don't know about any new
+        * protocol versions.
+        */
+       dev->protocol_version = 0;
+       printf("%s: ERROR: old EC interface not supported\n", __func__);
+       return -1;
+}
+
+int cros_ec_test(struct cros_ec_dev *dev)
+{
+       struct ec_params_hello req;
+       struct ec_response_hello *resp;
+
+       req.in_data = 0x12345678;
+       if (ec_command_inptr(dev, EC_CMD_HELLO, 0, &req, sizeof(req),
+                      (uint8_t **)&resp, sizeof(*resp)) < sizeof(*resp)) {
+               printf("ec_command_inptr() returned error\n");
+               return -1;
+       }
+       if (resp->out_data != req.in_data + 0x01020304) {
+               printf("Received invalid handshake %x\n", resp->out_data);
+               return -1;
+       }
+
+       return 0;
+}
+
+int cros_ec_flash_offset(struct cros_ec_dev *dev, enum ec_flash_region region,
+                     uint32_t *offset, uint32_t *size)
+{
+       struct ec_params_flash_region_info p;
+       struct ec_response_flash_region_info *r;
+       int ret;
+
+       p.region = region;
+       ret = ec_command_inptr(dev, EC_CMD_FLASH_REGION_INFO,
+                        EC_VER_FLASH_REGION_INFO,
+                        &p, sizeof(p), (uint8_t **)&r, sizeof(*r));
+       if (ret != sizeof(*r))
+               return -1;
+
+       if (offset)
+               *offset = r->offset;
+       if (size)
+               *size = r->size;
+
+       return 0;
+}
+
+int cros_ec_flash_erase(struct cros_ec_dev *dev, uint32_t offset, uint32_t size)
+{
+       struct ec_params_flash_erase p;
+
+       p.offset = offset;
+       p.size = size;
+       return ec_command_inptr(dev, EC_CMD_FLASH_ERASE, 0, &p, sizeof(p),
+                       NULL, 0);
+}
+
+/**
+ * Write a single block to the flash
+ *
+ * Write a block of data to the EC flash. The size must not exceed the flash
+ * write block size which you can obtain from cros_ec_flash_write_burst_size().
+ *
+ * The offset starts at 0. You can obtain the region information from
+ * cros_ec_flash_offset() to find out where to write for a particular region.
+ *
+ * Attempting to write to the region where the EC is currently running from
+ * will result in an error.
+ *
+ * @param dev          CROS-EC device
+ * @param data         Pointer to data buffer to write
+ * @param offset       Offset within flash to write to.
+ * @param size         Number of bytes to write
+ * @return 0 if ok, -1 on error
+ */
+static int cros_ec_flash_write_block(struct cros_ec_dev *dev,
+               const uint8_t *data, uint32_t offset, uint32_t size)
+{
+       struct ec_params_flash_write p;
+
+       p.offset = offset;
+       p.size = size;
+       assert(data && p.size <= EC_FLASH_WRITE_VER0_SIZE);
+       memcpy(&p + 1, data, p.size);
+
+       return ec_command_inptr(dev, EC_CMD_FLASH_WRITE, 0,
+                         &p, sizeof(p), NULL, 0) >= 0 ? 0 : -1;
+}
+
+/**
+ * Return optimal flash write burst size
+ */
+static int cros_ec_flash_write_burst_size(struct cros_ec_dev *dev)
+{
+       return EC_FLASH_WRITE_VER0_SIZE;
+}
+
+/**
+ * Check if a block of data is erased (all 0xff)
+ *
+ * This function is useful when dealing with flash, for checking whether a
+ * data block is erased and thus does not need to be programmed.
+ *
+ * @param data         Pointer to data to check (must be word-aligned)
+ * @param size         Number of bytes to check (must be word-aligned)
+ * @return 0 if erased, non-zero if any word is not erased
+ */
+static int cros_ec_data_is_erased(const uint32_t *data, int size)
+{
+       assert(!(size & 3));
+       size /= sizeof(uint32_t);
+       for (; size > 0; size -= 4, data++)
+               if (*data != -1U)
+                       return 0;
+
+       return 1;
+}
+
+int cros_ec_flash_write(struct cros_ec_dev *dev, const uint8_t *data,
+                    uint32_t offset, uint32_t size)
+{
+       uint32_t burst = cros_ec_flash_write_burst_size(dev);
+       uint32_t end, off;
+       int ret;
+
+       /*
+        * TODO: round up to the nearest multiple of write size.  Can get away
+        * without that on link right now because its write size is 4 bytes.
+        */
+       end = offset + size;
+       for (off = offset; off < end; off += burst, data += burst) {
+               uint32_t todo;
+
+               /* If the data is empty, there is no point in programming it */
+               todo = min(end - off, burst);
+               if (dev->optimise_flash_write &&
+                               cros_ec_data_is_erased((uint32_t *)data, todo))
+                       continue;
+
+               ret = cros_ec_flash_write_block(dev, data, off, todo);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+}
+
+/**
+ * Read a single block from the flash
+ *
+ * Read a block of data from the EC flash. The size must not exceed the flash
+ * write block size which you can obtain from cros_ec_flash_write_burst_size().
+ *
+ * The offset starts at 0. You can obtain the region information from
+ * cros_ec_flash_offset() to find out where to read for a particular region.
+ *
+ * @param dev          CROS-EC device
+ * @param data         Pointer to data buffer to read into
+ * @param offset       Offset within flash to read from
+ * @param size         Number of bytes to read
+ * @return 0 if ok, -1 on error
+ */
+static int cros_ec_flash_read_block(struct cros_ec_dev *dev, uint8_t *data,
+                                uint32_t offset, uint32_t size)
+{
+       struct ec_params_flash_read p;
+
+       p.offset = offset;
+       p.size = size;
+
+       return ec_command(dev, EC_CMD_FLASH_READ, 0,
+                         &p, sizeof(p), data, size) >= 0 ? 0 : -1;
+}
+
+int cros_ec_flash_read(struct cros_ec_dev *dev, uint8_t *data, uint32_t offset,
+                   uint32_t size)
+{
+       uint32_t burst = cros_ec_flash_write_burst_size(dev);
+       uint32_t end, off;
+       int ret;
+
+       end = offset + size;
+       for (off = offset; off < end; off += burst, data += burst) {
+               ret = cros_ec_flash_read_block(dev, data, off,
+                                           min(end - off, burst));
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+}
+
+int cros_ec_flash_update_rw(struct cros_ec_dev *dev,
+                        const uint8_t *image, int image_size)
+{
+       uint32_t rw_offset, rw_size;
+       int ret;
+
+       if (cros_ec_flash_offset(dev, EC_FLASH_REGION_RW, &rw_offset, &rw_size))
+               return -1;
+       if (image_size > (int)rw_size)
+               return -1;
+
+       /* Invalidate the existing hash, just in case the AP reboots
+        * unexpectedly during the update. If that happened, the EC RW firmware
+        * would be invalid, but the EC would still have the original hash.
+        */
+       ret = cros_ec_invalidate_hash(dev);
+       if (ret)
+               return ret;
+
+       /*
+        * Erase the entire RW section, so that the EC doesn't see any garbage
+        * past the new image if it's smaller than the current image.
+        *
+        * TODO: could optimize this to erase just the current image, since
+        * presumably everything past that is 0xff's.  But would still need to
+        * round up to the nearest multiple of erase size.
+        */
+       ret = cros_ec_flash_erase(dev, rw_offset, rw_size);
+       if (ret)
+               return ret;
+
+       /* Write the image */
+       ret = cros_ec_flash_write(dev, image, rw_offset, image_size);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+int cros_ec_read_vbnvcontext(struct cros_ec_dev *dev, uint8_t *block)
+{
+       struct ec_params_vbnvcontext p;
+       int len;
+
+       p.op = EC_VBNV_CONTEXT_OP_READ;
+
+       len = ec_command(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
+                       &p, sizeof(p), block, EC_VBNV_BLOCK_SIZE);
+       if (len < EC_VBNV_BLOCK_SIZE)
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_write_vbnvcontext(struct cros_ec_dev *dev, const uint8_t *block)
+{
+       struct ec_params_vbnvcontext p;
+       int len;
+
+       p.op = EC_VBNV_CONTEXT_OP_WRITE;
+       memcpy(p.block, block, sizeof(p.block));
+
+       len = ec_command_inptr(dev, EC_CMD_VBNV_CONTEXT, EC_VER_VBNV_CONTEXT,
+                       &p, sizeof(p), NULL, 0);
+       if (len < 0)
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_set_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t state)
+{
+       struct ec_params_ldo_set params;
+
+       params.index = index;
+       params.state = state;
+
+       if (ec_command_inptr(dev, EC_CMD_LDO_SET, 0,
+                      &params, sizeof(params),
+                      NULL, 0))
+               return -1;
+
+       return 0;
+}
+
+int cros_ec_get_ldo(struct cros_ec_dev *dev, uint8_t index, uint8_t *state)
+{
+       struct ec_params_ldo_get params;
+       struct ec_response_ldo_get *resp;
+
+       params.index = index;
+
+       if (ec_command_inptr(dev, EC_CMD_LDO_GET, 0,
+                      &params, sizeof(params),
+                      (uint8_t **)&resp, sizeof(*resp)) != sizeof(*resp))
+               return -1;
+
+       *state = resp->state;
+
+       return 0;
+}
+
+/**
+ * Decode EC interface details from the device tree and allocate a suitable
+ * device.
+ *
+ * @param blob         Device tree blob
+ * @param node         Node to decode from
+ * @param devp         Returns a pointer to the new allocated device
+ * @return 0 if ok, -1 on error
+ */
+static int cros_ec_decode_fdt(const void *blob, int node,
+               struct cros_ec_dev **devp)
+{
+       enum fdt_compat_id compat;
+       struct cros_ec_dev *dev;
+       int parent;
+
+       /* See what type of parent we are inside (this is expensive) */
+       parent = fdt_parent_offset(blob, node);
+       if (parent < 0) {
+               debug("%s: Cannot find node parent\n", __func__);
+               return -1;
+       }
+
+       dev = &static_dev;
+       dev->node = node;
+       dev->parent_node = parent;
+
+       compat = fdtdec_lookup(blob, parent);
+       switch (compat) {
+#ifdef CONFIG_CROS_EC_SPI
+       case COMPAT_SAMSUNG_EXYNOS_SPI:
+               dev->interface = CROS_EC_IF_SPI;
+               if (cros_ec_spi_decode_fdt(dev, blob))
+                       return -1;
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_I2C
+       case COMPAT_SAMSUNG_S3C2440_I2C:
+               dev->interface = CROS_EC_IF_I2C;
+               if (cros_ec_i2c_decode_fdt(dev, blob))
+                       return -1;
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_LPC
+       case COMPAT_INTEL_LPC:
+               dev->interface = CROS_EC_IF_LPC;
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_SANDBOX
+       case COMPAT_SANDBOX_HOST_EMULATION:
+               dev->interface = CROS_EC_IF_SANDBOX;
+               break;
+#endif
+       default:
+               debug("%s: Unknown compat id %d\n", __func__, compat);
+               return -1;
+       }
+
+       fdtdec_decode_gpio(blob, node, "ec-interrupt", &dev->ec_int);
+       dev->optimise_flash_write = fdtdec_get_bool(blob, node,
+                                                   "optimise-flash-write");
+       *devp = dev;
+
+       return 0;
+}
+
+int cros_ec_init(const void *blob, struct cros_ec_dev **cros_ecp)
+{
+       char id[MSG_BYTES];
+       struct cros_ec_dev *dev;
+       int node = 0;
+
+       *cros_ecp = NULL;
+       do {
+               node = fdtdec_next_compatible(blob, node,
+                                             COMPAT_GOOGLE_CROS_EC);
+               if (node < 0) {
+                       debug("%s: Node not found\n", __func__);
+                       return 0;
+               }
+       } while (!fdtdec_get_is_enabled(blob, node));
+
+       if (cros_ec_decode_fdt(blob, node, &dev)) {
+               debug("%s: Failed to decode device.\n", __func__);
+               return -CROS_EC_ERR_FDT_DECODE;
+       }
+
+       switch (dev->interface) {
+#ifdef CONFIG_CROS_EC_SPI
+       case CROS_EC_IF_SPI:
+               if (cros_ec_spi_init(dev, blob)) {
+                       debug("%s: Could not setup SPI interface\n", __func__);
+                       return -CROS_EC_ERR_DEV_INIT;
+               }
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_I2C
+       case CROS_EC_IF_I2C:
+               if (cros_ec_i2c_init(dev, blob))
+                       return -CROS_EC_ERR_DEV_INIT;
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_LPC
+       case CROS_EC_IF_LPC:
+               if (cros_ec_lpc_init(dev, blob))
+                       return -CROS_EC_ERR_DEV_INIT;
+               break;
+#endif
+#ifdef CONFIG_CROS_EC_SANDBOX
+       case CROS_EC_IF_SANDBOX:
+               if (cros_ec_sandbox_init(dev, blob))
+                       return -CROS_EC_ERR_DEV_INIT;
+               break;
+#endif
+       case CROS_EC_IF_NONE:
+       default:
+               return 0;
+       }
+
+       /* we will poll the EC interrupt line */
+       fdtdec_setup_gpio(&dev->ec_int);
+       if (fdt_gpio_isvalid(&dev->ec_int))
+               gpio_direction_input(dev->ec_int.gpio);
+
+       if (cros_ec_check_version(dev)) {
+               debug("%s: Could not detect CROS-EC version\n", __func__);
+               return -CROS_EC_ERR_CHECK_VERSION;
+       }
+
+       if (cros_ec_read_id(dev, id, sizeof(id))) {
+               debug("%s: Could not read KBC ID\n", __func__);
+               return -CROS_EC_ERR_READ_ID;
+       }
+
+       /* Remember this device for use by the cros_ec command */
+       last_dev = *cros_ecp = dev;
+       debug("Google Chrome EC CROS-EC driver ready, id '%s'\n", id);
+
+       return 0;
+}
+
+int cros_ec_decode_region(int argc, char * const argv[])
+{
+       if (argc > 0) {
+               if (0 == strcmp(*argv, "rw"))
+                       return EC_FLASH_REGION_RW;
+               else if (0 == strcmp(*argv, "ro"))
+                       return EC_FLASH_REGION_RO;
+
+               debug("%s: Invalid region '%s'\n", __func__, *argv);
+       } else {
+               debug("%s: Missing region parameter\n", __func__);
+       }
+
+       return -1;
+}
+
+int cros_ec_decode_ec_flash(const void *blob, struct fdt_cros_ec *config)
+{
+       int flash_node, node;
+
+       node = fdtdec_next_compatible(blob, 0, COMPAT_GOOGLE_CROS_EC);
+       if (node < 0) {
+               debug("Failed to find chrome-ec node'\n");
+               return -1;
+       }
+
+       flash_node = fdt_subnode_offset(blob, node, "flash");
+       if (flash_node < 0) {
+               debug("Failed to find flash node\n");
+               return -1;
+       }
+
+       if (fdtdec_read_fmap_entry(blob, flash_node, "flash",
+                                  &config->flash)) {
+               debug("Failed to decode flash node in chrome-ec'\n");
+               return -1;
+       }
+
+       config->flash_erase_value = fdtdec_get_int(blob, flash_node,
+                                                   "erase-value", -1);
+       for (node = fdt_first_subnode(blob, flash_node); node >= 0;
+            node = fdt_next_subnode(blob, node)) {
+               const char *name = fdt_get_name(blob, node, NULL);
+               enum ec_flash_region region;
+
+               if (0 == strcmp(name, "ro")) {
+                       region = EC_FLASH_REGION_RO;
+               } else if (0 == strcmp(name, "rw")) {
+                       region = EC_FLASH_REGION_RW;
+               } else if (0 == strcmp(name, "wp-ro")) {
+                       region = EC_FLASH_REGION_WP_RO;
+               } else {
+                       debug("Unknown EC flash region name '%s'\n", name);
+                       return -1;
+               }
+
+               if (fdtdec_read_fmap_entry(blob, node, "reg",
+                                          &config->region[region])) {
+                       debug("Failed to decode flash region in chrome-ec'\n");
+                       return -1;
+               }
+       }
+
+       return 0;
+}
+
+int cros_ec_i2c_xfer(struct cros_ec_dev *dev, uchar chip, uint addr,
+                    int alen, uchar *buffer, int len, int is_read)
+{
+       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 = &params.p;
+       struct ec_response_i2c_passthru *r = &response.r;
+       struct ec_params_i2c_passthru_msg *msg = p->msg;
+       uint8_t *pdata;
+       int read_len, write_len;
+       int size;
+       int rv;
+
+       p->port = 0;
+
+       if (alen != 1) {
+               printf("Unsupported address length %d\n", alen);
+               return -1;
+       }
+       if (is_read) {
+               read_len = len;
+               write_len = alen;
+               p->num_msgs = 2;
+       } else {
+               read_len = 0;
+               write_len = alen + len;
+               p->num_msgs = 1;
+       }
+
+       size = sizeof(*p) + p->num_msgs * sizeof(*msg);
+       if (size + write_len > sizeof(params)) {
+               puts("Params too large for buffer\n");
+               return -1;
+       }
+       if (sizeof(*r) + read_len > sizeof(response)) {
+               puts("Read length too big for buffer\n");
+               return -1;
+       }
+
+       /* Create a message to write the register address and optional data */
+       pdata = (uint8_t *)p + size;
+       msg->addr_flags = chip;
+       msg->len = write_len;
+       pdata[0] = addr;
+       if (!is_read)
+               memcpy(pdata + 1, buffer, len);
+       msg++;
+
+       if (read_len) {
+               msg->addr_flags = chip | EC_I2C_FLAG_READ;
+               msg->len = read_len;
+       }
+
+       rv = ec_command(dev, EC_CMD_I2C_PASSTHRU, 0, p, size + write_len,
+                       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;
+       }
+
+       if (read_len)
+               memcpy(buffer, r->data, read_len);
+
+       return 0;
+}
+
+#ifdef CONFIG_CMD_CROS_EC
+
+/**
+ * Perform a flash read or write command
+ *
+ * @param dev          CROS-EC device to read/write
+ * @param is_write     1 do to a write, 0 to do a read
+ * @param argc         Number of arguments
+ * @param argv         Arguments (2 is region, 3 is address)
+ * @return 0 for ok, 1 for a usage error or -ve for ec command error
+ *     (negative EC_RES_...)
+ */
+static int do_read_write(struct cros_ec_dev *dev, int is_write, int argc,
+                        char * const argv[])
+{
+       uint32_t offset, size = -1U, region_size;
+       unsigned long addr;
+       char *endp;
+       int region;
+       int ret;
+
+       region = cros_ec_decode_region(argc - 2, argv + 2);
+       if (region == -1)
+               return 1;
+       if (argc < 4)
+               return 1;
+       addr = simple_strtoul(argv[3], &endp, 16);
+       if (*argv[3] == 0 || *endp != 0)
+               return 1;
+       if (argc > 4) {
+               size = simple_strtoul(argv[4], &endp, 16);
+               if (*argv[4] == 0 || *endp != 0)
+                       return 1;
+       }
+
+       ret = cros_ec_flash_offset(dev, region, &offset, &region_size);
+       if (ret) {
+               debug("%s: Could not read region info\n", __func__);
+               return ret;
+       }
+       if (size == -1U)
+               size = region_size;
+
+       ret = is_write ?
+               cros_ec_flash_write(dev, (uint8_t *)addr, offset, size) :
+               cros_ec_flash_read(dev, (uint8_t *)addr, offset, size);
+       if (ret) {
+               debug("%s: Could not %s region\n", __func__,
+                     is_write ? "write" : "read");
+               return ret;
+       }
+
+       return 0;
+}
+
+/**
+ * get_alen() - Small parser helper function to get address length
+ *
+ * Returns the address length.
+ */
+static uint get_alen(char *arg)
+{
+       int     j;
+       int     alen;
+
+       alen = 1;
+       for (j = 0; j < 8; j++) {
+               if (arg[j] == '.') {
+                       alen = arg[j+1] - '0';
+                       break;
+               } else if (arg[j] == '\0') {
+                       break;
+               }
+       }
+       return alen;
+}
+
+#define DISP_LINE_LEN  16
+
+/*
+ * TODO(sjg@chromium.org): This code copied almost verbatim from cmd_i2c.c
+ * so we can remove it later.
+ */
+static int cros_ec_i2c_md(struct cros_ec_dev *dev, int flag, int argc,
+                         char * const argv[])
+{
+       u_char  chip;
+       uint    addr, alen, length = 0x10;
+       int     j, nbytes, linebytes;
+
+       if (argc < 2)
+               return CMD_RET_USAGE;
+
+       if (1 || (flag & CMD_FLAG_REPEAT) == 0) {
+               /*
+                * New command specified.
+                */
+
+               /*
+                * I2C chip address
+                */
+               chip = simple_strtoul(argv[0], NULL, 16);
+
+               /*
+                * I2C data address within the chip.  This can be 1 or
+                * 2 bytes long.  Some day it might be 3 bytes long :-).
+                */
+               addr = simple_strtoul(argv[1], NULL, 16);
+               alen = get_alen(argv[1]);
+               if (alen > 3)
+                       return CMD_RET_USAGE;
+
+               /*
+                * If another parameter, it is the length to display.
+                * Length is the number of objects, not number of bytes.
+                */
+               if (argc > 2)
+                       length = simple_strtoul(argv[2], NULL, 16);
+       }
+
+       /*
+        * Print the lines.
+        *
+        * We buffer all read data, so we can make sure data is read only
+        * once.
+        */
+       nbytes = length;
+       do {
+               unsigned char   linebuf[DISP_LINE_LEN];
+               unsigned char   *cp;
+
+               linebytes = (nbytes > DISP_LINE_LEN) ? DISP_LINE_LEN : nbytes;
+
+               if (cros_ec_i2c_xfer(dev, chip, addr, alen, linebuf, linebytes,
+                                    1))
+                       puts("Error reading the chip.\n");
+               else {
+                       printf("%04x:", addr);
+                       cp = linebuf;
+                       for (j = 0; j < linebytes; j++) {
+                               printf(" %02x", *cp++);
+                               addr++;
+                       }
+                       puts("    ");
+                       cp = linebuf;
+                       for (j = 0; j < linebytes; j++) {
+                               if ((*cp < 0x20) || (*cp > 0x7e))
+                                       puts(".");
+                               else
+                                       printf("%c", *cp);
+                               cp++;
+                       }
+                       putc('\n');
+               }
+               nbytes -= linebytes;
+       } while (nbytes > 0);
+
+       return 0;
+}
+
+static int cros_ec_i2c_mw(struct cros_ec_dev *dev, int flag, int argc,
+                         char * const argv[])
+{
+       uchar   chip;
+       ulong   addr;
+       uint    alen;
+       uchar   byte;
+       int     count;
+
+       if ((argc < 3) || (argc > 4))
+               return CMD_RET_USAGE;
+
+       /*
+        * Chip is always specified.
+        */
+       chip = simple_strtoul(argv[0], NULL, 16);
+
+       /*
+        * Address is always specified.
+        */
+       addr = simple_strtoul(argv[1], NULL, 16);
+       alen = get_alen(argv[1]);
+       if (alen > 3)
+               return CMD_RET_USAGE;
+
+       /*
+        * Value to write is always specified.
+        */
+       byte = simple_strtoul(argv[2], NULL, 16);
+
+       /*
+        * Optional count
+        */
+       if (argc == 4)
+               count = simple_strtoul(argv[3], NULL, 16);
+       else
+               count = 1;
+
+       while (count-- > 0) {
+               if (cros_ec_i2c_xfer(dev, chip, addr++, alen, &byte, 1, 0))
+                       puts("Error writing the chip.\n");
+               /*
+                * Wait for the write to complete.  The write can take
+                * up to 10mSec (we allow a little more time).
+                */
+/*
+ * No write delay with FRAM devices.
+ */
+#if !defined(CONFIG_SYS_I2C_FRAM)
+               udelay(11000);
+#endif
+       }
+
+       return 0;
+}
+
+/* Temporary code until we have driver model and can use the i2c command */
+static int cros_ec_i2c_passthrough(struct cros_ec_dev *dev, int flag,
+                                  int argc, char * const argv[])
+{
+       const char *cmd;
+
+       if (argc < 1)
+               return CMD_RET_USAGE;
+       cmd = *argv++;
+       argc--;
+       if (0 == strcmp("md", cmd))
+               cros_ec_i2c_md(dev, flag, argc, argv);
+       else if (0 == strcmp("mw", cmd))
+               cros_ec_i2c_mw(dev, flag, argc, argv);
+       else
+               return CMD_RET_USAGE;
+
+       return 0;
+}
+
+static int do_cros_ec(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+       struct cros_ec_dev *dev = last_dev;
+       const char *cmd;
+       int ret = 0;
+
+       if (argc < 2)
+               return CMD_RET_USAGE;
+
+       cmd = argv[1];
+       if (0 == strcmp("init", cmd)) {
+               ret = cros_ec_init(gd->fdt_blob, &dev);
+               if (ret) {
+                       printf("Could not init cros_ec device (err %d)\n", ret);
+                       return 1;
+               }
+               return 0;
+       }
+
+       /* Just use the last allocated device; there should be only one */
+       if (!last_dev) {
+               printf("No CROS-EC device available\n");
+               return 1;
+       }
+       if (0 == strcmp("id", cmd)) {
+               char id[MSG_BYTES];
+
+               if (cros_ec_read_id(dev, id, sizeof(id))) {
+                       debug("%s: Could not read KBC ID\n", __func__);
+                       return 1;
+               }
+               printf("%s\n", id);
+       } else if (0 == strcmp("info", cmd)) {
+               struct ec_response_mkbp_info info;
+
+               if (cros_ec_info(dev, &info)) {
+                       debug("%s: Could not read KBC info\n", __func__);
+                       return 1;
+               }
+               printf("rows     = %u\n", info.rows);
+               printf("cols     = %u\n", info.cols);
+               printf("switches = %#x\n", info.switches);
+       } else if (0 == strcmp("curimage", cmd)) {
+               enum ec_current_image image;
+
+               if (cros_ec_read_current_image(dev, &image)) {
+                       debug("%s: Could not read KBC image\n", __func__);
+                       return 1;
+               }
+               printf("%d\n", image);
+       } else if (0 == strcmp("hash", cmd)) {
+               struct ec_response_vboot_hash hash;
+               int i;
+
+               if (cros_ec_read_hash(dev, &hash)) {
+                       debug("%s: Could not read KBC hash\n", __func__);
+                       return 1;
+               }
+
+               if (hash.hash_type == EC_VBOOT_HASH_TYPE_SHA256)
+                       printf("type:    SHA-256\n");
+               else
+                       printf("type:    %d\n", hash.hash_type);
+
+               printf("offset:  0x%08x\n", hash.offset);
+               printf("size:    0x%08x\n", hash.size);
+
+               printf("digest:  ");
+               for (i = 0; i < hash.digest_size; i++)
+                       printf("%02x", hash.hash_digest[i]);
+               printf("\n");
+       } else if (0 == strcmp("reboot", cmd)) {
+               int region;
+               enum ec_reboot_cmd cmd;
+
+               if (argc >= 3 && !strcmp(argv[2], "cold"))
+                       cmd = EC_REBOOT_COLD;
+               else {
+                       region = cros_ec_decode_region(argc - 2, argv + 2);
+                       if (region == EC_FLASH_REGION_RO)
+                               cmd = EC_REBOOT_JUMP_RO;
+                       else if (region == EC_FLASH_REGION_RW)
+                               cmd = EC_REBOOT_JUMP_RW;
+                       else
+                               return CMD_RET_USAGE;
+               }
+
+               if (cros_ec_reboot(dev, cmd, 0)) {
+                       debug("%s: Could not reboot KBC\n", __func__);
+                       return 1;
+               }
+       } else if (0 == strcmp("events", cmd)) {
+               uint32_t events;
+
+               if (cros_ec_get_host_events(dev, &events)) {
+                       debug("%s: Could not read host events\n", __func__);
+                       return 1;
+               }
+               printf("0x%08x\n", events);
+       } else if (0 == strcmp("clrevents", cmd)) {
+               uint32_t events = 0x7fffffff;
+
+               if (argc >= 3)
+                       events = simple_strtol(argv[2], NULL, 0);
+
+               if (cros_ec_clear_host_events(dev, events)) {
+                       debug("%s: Could not clear host events\n", __func__);
+                       return 1;
+               }
+       } else if (0 == strcmp("read", cmd)) {
+               ret = do_read_write(dev, 0, argc, argv);
+               if (ret > 0)
+                       return CMD_RET_USAGE;
+       } else if (0 == strcmp("write", cmd)) {
+               ret = do_read_write(dev, 1, argc, argv);
+               if (ret > 0)
+                       return CMD_RET_USAGE;
+       } else if (0 == strcmp("erase", cmd)) {
+               int region = cros_ec_decode_region(argc - 2, argv + 2);
+               uint32_t offset, size;
+
+               if (region == -1)
+                       return CMD_RET_USAGE;
+               if (cros_ec_flash_offset(dev, region, &offset, &size)) {
+                       debug("%s: Could not read region info\n", __func__);
+                       ret = -1;
+               } else {
+                       ret = cros_ec_flash_erase(dev, offset, size);
+                       if (ret) {
+                               debug("%s: Could not erase region\n",
+                                     __func__);
+                       }
+               }
+       } else if (0 == strcmp("regioninfo", cmd)) {
+               int region = cros_ec_decode_region(argc - 2, argv + 2);
+               uint32_t offset, size;
+
+               if (region == -1)
+                       return CMD_RET_USAGE;
+               ret = cros_ec_flash_offset(dev, region, &offset, &size);
+               if (ret) {
+                       debug("%s: Could not read region info\n", __func__);
+               } else {
+                       printf("Region: %s\n", region == EC_FLASH_REGION_RO ?
+                                       "RO" : "RW");
+                       printf("Offset: %x\n", offset);
+                       printf("Size:   %x\n", size);
+               }
+       } else if (0 == strcmp("vbnvcontext", cmd)) {
+               uint8_t block[EC_VBNV_BLOCK_SIZE];
+               char buf[3];
+               int i, len;
+               unsigned long result;
+
+               if (argc <= 2) {
+                       ret = cros_ec_read_vbnvcontext(dev, block);
+                       if (!ret) {
+                               printf("vbnv_block: ");
+                               for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++)
+                                       printf("%02x", block[i]);
+                               putc('\n');
+                       }
+               } else {
+                       /*
+                        * TODO(clchiou): Move this to a utility function as
+                        * cmd_spi might want to call it.
+                        */
+                       memset(block, 0, EC_VBNV_BLOCK_SIZE);
+                       len = strlen(argv[2]);
+                       buf[2] = '\0';
+                       for (i = 0; i < EC_VBNV_BLOCK_SIZE; i++) {
+                               if (i * 2 >= len)
+                                       break;
+                               buf[0] = argv[2][i * 2];
+                               if (i * 2 + 1 >= len)
+                                       buf[1] = '0';
+                               else
+                                       buf[1] = argv[2][i * 2 + 1];
+                               strict_strtoul(buf, 16, &result);
+                               block[i] = result;
+                       }
+                       ret = cros_ec_write_vbnvcontext(dev, block);
+               }
+               if (ret) {
+                       debug("%s: Could not %s VbNvContext\n", __func__,
+                                       argc <= 2 ?  "read" : "write");
+               }
+       } else if (0 == strcmp("test", cmd)) {
+               int result = cros_ec_test(dev);
+
+               if (result)
+                       printf("Test failed with error %d\n", result);
+               else
+                       puts("Test passed\n");
+       } else if (0 == strcmp("version", cmd)) {
+               struct ec_response_get_version *p;
+               char *build_string;
+
+               ret = cros_ec_read_version(dev, &p);
+               if (!ret) {
+                       /* Print versions */
+                       printf("RO version:    %1.*s\n",
+                              (int)sizeof(p->version_string_ro),
+                              p->version_string_ro);
+                       printf("RW version:    %1.*s\n",
+                              (int)sizeof(p->version_string_rw),
+                              p->version_string_rw);
+                       printf("Firmware copy: %s\n",
+                               (p->current_image <
+                                       ARRAY_SIZE(ec_current_image_name) ?
+                               ec_current_image_name[p->current_image] :
+                               "?"));
+                       ret = cros_ec_read_build_info(dev, &build_string);
+                       if (!ret)
+                               printf("Build info:    %s\n", build_string);
+               }
+       } else if (0 == strcmp("ldo", cmd)) {
+               uint8_t index, state;
+               char *endp;
+
+               if (argc < 3)
+                       return CMD_RET_USAGE;
+               index = simple_strtoul(argv[2], &endp, 10);
+               if (*argv[2] == 0 || *endp != 0)
+                       return CMD_RET_USAGE;
+               if (argc > 3) {
+                       state = simple_strtoul(argv[3], &endp, 10);
+                       if (*argv[3] == 0 || *endp != 0)
+                               return CMD_RET_USAGE;
+                       ret = cros_ec_set_ldo(dev, index, state);
+               } else {
+                       ret = cros_ec_get_ldo(dev, index, &state);
+                       if (!ret) {
+                               printf("LDO%d: %s\n", index,
+                                       state == EC_LDO_STATE_ON ?
+                                       "on" : "off");
+                       }
+               }
+
+               if (ret) {
+                       debug("%s: Could not access LDO%d\n", __func__, index);
+                       return ret;
+               }
+       } else if (0 == strcmp("i2c", cmd)) {
+               ret = cros_ec_i2c_passthrough(dev, flag, argc - 2, argv + 2);
+       } else {
+               return CMD_RET_USAGE;
+       }
+
+       if (ret < 0) {
+               printf("Error: CROS-EC command failed (error %d)\n", ret);
+               ret = 1;
+       }
+
+       return ret;
+}
+
+U_BOOT_CMD(
+       crosec, 6,      1,      do_cros_ec,
+       "CROS-EC utility command",
+       "init                Re-init CROS-EC (done on startup automatically)\n"
+       "crosec id                  Read CROS-EC ID\n"
+       "crosec info                Read CROS-EC info\n"
+       "crosec curimage            Read CROS-EC current image\n"
+       "crosec hash                Read CROS-EC hash\n"
+       "crosec reboot [rw | ro | cold]  Reboot CROS-EC\n"
+       "crosec events              Read CROS-EC host events\n"
+       "crosec clrevents [mask]    Clear CROS-EC host events\n"
+       "crosec regioninfo <ro|rw>  Read image info\n"
+       "crosec erase <ro|rw>       Erase EC image\n"
+       "crosec read <ro|rw> <addr> [<size>]   Read EC image\n"
+       "crosec write <ro|rw> <addr> [<size>]  Write EC image\n"
+       "crosec vbnvcontext [hexstring]        Read [write] VbNvContext from EC\n"
+       "crosec ldo <idx> [<state>] Switch/Read LDO state\n"
+       "crosec test                run tests on cros_ec\n"
+       "crosec version             Read CROS-EC version\n"
+       "crosec i2c md chip address[.0, .1, .2] [# of objects] - read from I2C passthru\n"
+       "crosec i2c mw chip address[.0, .1, .2] value [count] - write to I2C passthru (fill)"
+);
+#endif