Re: [Qemu-devel] [PATCH] Extend support of SMBUS(module pm_smbus.c) HST_STS register.

[Maksim Ratnikov <m.o.ratnikov@gmail.com>]

Previous realization doesn't consider flags in the status register.
Add DS and INTR bits of HST_STS register set after transaction execution.
Update bits resetting in HST_STS register. Update error processing: if 
DEV_ERR bit are set
transaction isn't execution.


Signed-off-by: Maksim_Ratnikov <m.o.ratnikov@gmail.com>
---
  hw/i2c/pm_smbus.c |   25 +++++++++++++++++++++++--
  1 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/hw/i2c/pm_smbus.c b/hw/i2c/pm_smbus.c
index 0b5bb89..35f154e 100644
--- a/hw/i2c/pm_smbus.c
+++ b/hw/i2c/pm_smbus.c
@@ -32,6 +32,18 @@
  #define SMBHSTDAT1      0x06
  #define SMBBLKDAT       0x07

+#define STS_HOST_BUSY   (1)
+#define STS_INTR        (1<<1)
+#define STS_DEV_ERR     (1<<2)
+#define STS_BUS_ERR     (1<<3)
+#define STS_FAILED      (1<<4)
+#define STS_SMBALERT    (1<<5)
+#define STS_INUSE_STS   (1<<6)
+#define STS_BYTE_DONE   (1<<7)
+/* Signs of successfully transaction end :
+*  ByteDoneStatus = 1 (STS_BYTE_DONE) and INTR = 1 (STS_INTR )
+*/
+
  //#define DEBUG

  #ifdef DEBUG
@@ -50,9 +62,14 @@ static void smb_transaction(PMSMBus *s)
      i2c_bus *bus = s->smbus;

      SMBUS_DPRINTF("SMBus trans addr=0x%02x prot=0x%02x\n", addr, prot);
+    /* Transaction isn't exec if STS_DEV_ERR bit set */
+    if ((s->smb_stat & STS_DEV_ERR) != 0)  {
+            goto error;
+        }
      switch(prot) {
      case 0x0:
          smbus_quick_command(bus, addr, read);
+        s->smb_stat |= STS_BYTE_DONE | STS_INTR;
          break;
      case 0x1:
          if (read) {
@@ -60,6 +77,7 @@ static void smb_transaction(PMSMBus *s)
          } else {
              smbus_send_byte(bus, addr, cmd);
          }
+        s->smb_stat |= STS_BYTE_DONE | STS_INTR;
          break;
      case 0x2:
          if (read) {
@@ -67,6 +85,7 @@ static void smb_transaction(PMSMBus *s)
          } else {
              smbus_write_byte(bus, addr, cmd, s->smb_data0);
          }
+        s->smb_stat |= STS_BYTE_DONE | STS_INTR;
          break;
      case 0x3:
          if (read) {
@@ -77,6 +96,7 @@ static void smb_transaction(PMSMBus *s)
          } else {
              smbus_write_word(bus, addr, cmd, (s->smb_data1 << 8) | 
s->smb_data0);
          }
+        s->smb_stat |= STS_BYTE_DONE | STS_INTR;
          break;
      case 0x5:
          if (read) {
@@ -84,6 +104,7 @@ static void smb_transaction(PMSMBus *s)
          } else {
              smbus_write_block(bus, addr, cmd, s->smb_data, s->smb_data0);
          }
+        s->smb_stat |= STS_BYTE_DONE | STS_INTR;
          break;
      default:
          goto error;
@@ -91,7 +112,7 @@ static void smb_transaction(PMSMBus *s)
      return;

    error:
-    s->smb_stat |= 0x04;
+    s->smb_stat |= STS_DEV_ERR;
  }

  static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val,
@@ -102,7 +123,7 @@ static void smb_ioport_writeb(void *opaque, hwaddr 
addr, uint64_t val,
      SMBUS_DPRINTF("SMB writeb port=0x%04x val=0x%02x\n", addr, val);
      switch(addr) {
      case SMBHSTSTS:
-        s->smb_stat = 0;
+        s->smb_stat = (~(val & 0xff)) & s->smb_stat;
          s->smb_index = 0;
          break;
      case SMBHSTCNT:
-- 
1.7.3.4