Patchwork [1/3] smbus: fix writes

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Submitter Paolo Bonzini
Date Feb. 4, 2012, 8:03 a.m.
Message ID <1328342612-25826-2-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/139558/
State New
Headers show

Comments

Paolo Bonzini - Feb. 4, 2012, 8:03 a.m.
SMBus protocol sends offset and length before the actual data that
is transferred.  So we need to skip two bytes rather than one.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/smbus.c |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)

Patch

diff --git a/hw/smbus.c b/hw/smbus.c
index 77626f3..4ff2342 100644
--- a/hw/smbus.c
+++ b/hw/smbus.c
@@ -59,9 +59,12 @@  static void smbus_do_write(SMBusDevice *dev)
     } else {
         dev->command = dev->data_buf[0];
         DPRINTF("Command %d len %d\n", dev->command, dev->data_len - 1);
+        if (dev->data_buf[1] > dev->data_len - 2) {
+            fprintf(stderr, "SMBus data transfer overrun!\n");
+        }
         if (sc->write_data) {
-            sc->write_data(dev, dev->command, dev->data_buf + 1,
-                           dev->data_len - 1);
+            sc->write_data(dev, dev->command, dev->data_buf + 2,
+                           MIN(dev->data_buf[1], dev->data_len - 2));
         }
     }
 }