i2c:pm_smbus: Fix pm_smbus handling of I2C block read

The I2C block read function of pm_smbus was completely broken.  It
required doing some direct I2C handling because it didn't have a
defined size, the OS code just reads bytes until it marks the
transaction finished.

This also required adjusting how the AMIBIOS workaround code worked,
the I2C block mode was setting STS_HOST_BUSY during a transaction,
so that bit could no longer be used to inform the host status read
code to start the transaction.  Create a explicit bool for that
operation.

Also, don't read the next byte from the device in byte-by-byte
mode unless the OS is actually clearing the byte done bit.  Just
assuming that's what the OS is doing is a bad idea.

Signed-off-by: Corey Minyard <cminyard@mvista.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/hw/i2c/pm_smbus.h b/include/hw/i2c/pm_smbus.h
index 6dd5b7040b..7bcca97672 100644
--- a/include/hw/i2c/pm_smbus.h
+++ b/include/hw/i2c/pm_smbus.h
@@ -33,6 +33,12 @@ typedef struct PMSMBus {
     /* Set on block transfers after the last byte has been read, so the
        INTR bit can be set at the right time. */
     bool op_done;
+
+    /* Set during an I2C block read, so we know how to handle data. */
+    bool in_i2c_block_read;
+
+    /* Used to work around a bug in AMIBIOS, see smb_transaction_start() */
+    bool start_transaction_on_status_read;
 } PMSMBus;
 
 void pm_smbus_init(DeviceState *parent, PMSMBus *smb, bool force_aux_blk);