When EC burst mode is activated and multiple bytes are accessed, do not

disable and enable repeatedly, just do it once per call.  It also reduces
code duplication.  Check all parameters early and fail immediately.

1 files changed, 27 insertions, 54 deletions

diff --git a/sys/dev/acpica/acpi_ec.c b/sys/dev/acpica/acpi_ec.c
index 94dca9e..2c18972 100644
--- a/sys/dev/acpica/acpi_ec.c
+++ b/sys/dev/acpica/acpi_ec.c
@@ -720,24 +720,19 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
 	       UINT64 *Value, void *Context, void *RegionContext)
 {
     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
-    ACPI_STATUS			Status;
+    ACPI_PHYSICAL_ADDRESS	EcAddr;
     UINT8			*EcData;
-    UINT8			EcAddr;
-    int				bytes, i;
+    ACPI_STATUS			Status;
 
     ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)Address);
 
+    if (Function != ACPI_READ && Function != ACPI_WRITE)
+	return_ACPI_STATUS (AE_BAD_PARAMETER);
     if (Width % 8 != 0 || Value == NULL || Context == NULL)
 	return_ACPI_STATUS (AE_BAD_PARAMETER);
-    bytes = Width / 8;
-    if (Address + bytes - 1 > 0xFF)
+    if (Address + Width / 8 > 256)
 	return_ACPI_STATUS (AE_BAD_ADDRESS);
 
-    if (Function == ACPI_READ)
-	*Value = 0;
-    EcAddr = Address;
-    EcData = (UINT8 *)Value;
-
     /*
      * If booting, check if we need to run the query handler.  If so, we
      * we call it directly here since our thread taskq is not active yet.
@@ -754,8 +749,21 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
     if (ACPI_FAILURE(Status))
 	return_ACPI_STATUS (Status);
 
+    /* If we can't start burst mode, continue anyway. */
+    Status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
+    if (ACPI_SUCCESS(Status)) {
+	if (EC_GET_DATA(sc) == EC_BURST_ACK) {
+	    CTR0(KTR_ACPI, "ec burst enabled");
+	    sc->ec_burstactive = TRUE;
+	}
+    }
+
     /* Perform the transaction(s), based on Width. */
-    for (i = 0; i < bytes; i++, EcAddr++, EcData++) {
+    EcAddr = Address;
+    EcData = (UINT8 *)Value;
+    if (Function == ACPI_READ)
+	*Value = 0;
+    do {
 	switch (Function) {
 	case ACPI_READ:
 	    Status = EcRead(sc, EcAddr, EcData);
@@ -763,14 +771,17 @@ EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 Width,
 	case ACPI_WRITE:
 	    Status = EcWrite(sc, EcAddr, *EcData);
 	    break;
-	default:
-	    device_printf(sc->ec_dev, "invalid EcSpaceHandler function %d\n",
-			  Function);
-	    Status = AE_BAD_PARAMETER;
-	    break;
 	}
 	if (ACPI_FAILURE(Status))
 	    break;
+	EcAddr++;
+	EcData++;
+    } while (EcAddr < Address + Width / 8);
+
+    if (sc->ec_burstactive) {
+	sc->ec_burstactive = FALSE;
+	if (ACPI_SUCCESS(EcCommand(sc, EC_COMMAND_BURST_DISABLE)))
+	    CTR0(KTR_ACPI, "ec disabled burst ok");
     }
 
     EcUnlock(sc);
@@ -943,22 +954,11 @@ static ACPI_STATUS
 EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
 {
     ACPI_STATUS	status;
-    UINT8 data;
     u_int gen_count;
 
     ACPI_SERIAL_ASSERT(ec);
     CTR1(KTR_ACPI, "ec read from %#x", Address);
 
-    /* If we can't start burst mode, continue anyway. */
-    status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
-    if (status == AE_OK) {
-    	data = EC_GET_DATA(sc);
-	if (data == EC_BURST_ACK) {
-	    CTR0(KTR_ACPI, "ec burst enabled");
-	    sc->ec_burstactive = TRUE;
-	}
-    }
-
     status = EcCommand(sc, EC_COMMAND_READ);
     if (ACPI_FAILURE(status))
 	return (status);
@@ -972,14 +972,6 @@ EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
     }
     *Data = EC_GET_DATA(sc);
 
-    if (sc->ec_burstactive) {
-	sc->ec_burstactive = FALSE;
-	status = EcCommand(sc, EC_COMMAND_BURST_DISABLE);
-	if (ACPI_FAILURE(status))
-	    return (status);
-	CTR0(KTR_ACPI, "ec disabled burst ok");
-    }
-
     return (AE_OK);
 }
 
@@ -987,22 +979,11 @@ static ACPI_STATUS
 EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 Data)
 {
     ACPI_STATUS	status;
-    UINT8 data;
     u_int gen_count;
 
     ACPI_SERIAL_ASSERT(ec);
     CTR2(KTR_ACPI, "ec write to %#x, data %#x", Address, Data);
 
-    /* If we can't start burst mode, continue anyway. */
-    status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
-    if (status == AE_OK) {
-    	data = EC_GET_DATA(sc);
-	if (data == EC_BURST_ACK) {
-	    CTR0(KTR_ACPI, "ec burst enabled");
-	    sc->ec_burstactive = TRUE;
-	}
-    }
-
     status = EcCommand(sc, EC_COMMAND_WRITE);
     if (ACPI_FAILURE(status))
 	return (status);
@@ -1023,13 +1004,5 @@ EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 Data)
 	return (status);
     }
 
-    if (sc->ec_burstactive) {
-	sc->ec_burstactive = FALSE;
-	status = EcCommand(sc, EC_COMMAND_BURST_DISABLE);
-	if (ACPI_FAILURE(status))
-	    return (status);
-	CTR0(KTR_ACPI, "ec disabled burst ok");
-    }
-
     return (AE_OK);
 }