2 files changed, 36 insertions, 1 deletions

diff --git a/hw/i2c/pmbus_device.c b/hw/i2c/pmbus_device.c
index cef51663d0..ea15490720 100644
--- a/hw/i2c/pmbus_device.c
+++ b/hw/i2c/pmbus_device.c
@@ -102,7 +102,6 @@ void pmbus_send_string(PMBusDevice *pmdev, const char *data)
     }
 
     size_t len = strlen(data);
-    g_assert(len > 0);
     g_assert(len + pmdev->out_buf_len < SMBUS_DATA_MAX_LEN);
     pmdev->out_buf[len + pmdev->out_buf_len] = len;
 
@@ -112,6 +111,35 @@ void pmbus_send_string(PMBusDevice *pmdev, const char *data)
     pmdev->out_buf_len += len + 1;
 }
 
+uint8_t pmbus_receive_block(PMBusDevice *pmdev, uint8_t *dest, size_t len)
+{
+    /* dest may contain data from previous writes */
+    memset(dest, 0, len);
+
+    /* Exclude command code from return value */
+    pmdev->in_buf++;
+    pmdev->in_buf_len--;
+
+    /* The byte after the command code denotes the length */
+    uint8_t sent_len = pmdev->in_buf[0];
+
+    if (sent_len != pmdev->in_buf_len - 1) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: length mismatch. Expected %d bytes, got %d bytes\n",
+                      __func__, sent_len, pmdev->in_buf_len - 1);
+    }
+
+    /* exclude length byte */
+    pmdev->in_buf++;
+    pmdev->in_buf_len--;
+
+    if (pmdev->in_buf_len < len) {
+        len = pmdev->in_buf_len;
+    }
+    memcpy(dest, pmdev->in_buf, len);
+    return len;
+}
+
 
 static uint64_t pmbus_receive_uint(PMBusDevice *pmdev)
 {
diff --git a/include/hw/i2c/pmbus_device.h b/include/hw/i2c/pmbus_device.h
index 93f5d57c9d..7dc00cc4d9 100644
--- a/include/hw/i2c/pmbus_device.h
+++ b/include/hw/i2c/pmbus_device.h
@@ -502,6 +502,13 @@ void pmbus_send64(PMBusDevice *state, uint64_t data);
 void pmbus_send_string(PMBusDevice *state, const char *data);
 
 /**
+ * @brief Receive data sent with Block Write.
+ * @param dest - memory with enough capacity to receive the write
+ * @param len - the capacity of dest
+ */
+uint8_t pmbus_receive_block(PMBusDevice *pmdev, uint8_t *dest, size_t len);
+
+/**
  * @brief Receive data over PMBus
  * These methods help track how much data is being received over PMBus
  * Log to GUEST_ERROR if too much or too little is sent.