astlpc: Use enums instead of hardcoded numbers

This makes it slightly easier to read the code.

Change-Id: Iab8df93fc330fda4b89d2a77922ca73f7a7ad1a1
Signed-off-by: Rashmica Gupta <rashmica@linux.ibm.com>
diff --git a/astlpc.c b/astlpc.c
index 0281099..6842ae1 100644
--- a/astlpc.c
+++ b/astlpc.c
@@ -41,6 +41,13 @@
 
 #endif
 
+enum mctp_astlpc_cmd {
+	cmd_initialise = 0x00,
+	cmd_tx_begin = 0x01,
+	cmd_rx_complete = 0x02,
+	cmd_dummy_value = 0xff,
+};
+
 enum mctp_astlpc_buffer_state {
 	/*
 	 * Prior to "Channel Ready" we mark the buffers as "idle" to catch illegal accesses. In this
@@ -353,7 +360,7 @@
 	 * So, write a dummy value of 0xff to ODR, which will ensure that an
 	 * interrupt is triggered, and can be ignored by the host.
 	 */
-	data = 0xff;
+	data = cmd_dummy_value;
 
 	rc = mctp_astlpc_kcs_write(astlpc, MCTP_ASTLPC_KCS_REG_STATUS, status);
 	if (rc) {
@@ -784,7 +791,7 @@
 }
 
 static int mctp_astlpc_kcs_send(struct mctp_binding_astlpc *astlpc,
-				uint8_t data)
+				enum mctp_astlpc_cmd data)
 {
 	uint8_t status;
 	int rc;
@@ -842,7 +849,7 @@
 
 	astlpc->layout.tx.state = buffer_state_prepared;
 
-	rc = mctp_astlpc_kcs_send(astlpc, 0x1);
+	rc = mctp_astlpc_kcs_send(astlpc, cmd_tx_begin);
 	if (!rc)
 		astlpc->layout.tx.state = buffer_state_released;
 
@@ -1016,7 +1023,7 @@
 	/* Inform the other side of the MCTP interface that we have read
 	 * the packet off the bus before handling the contents of the packet.
 	 */
-	if (!mctp_astlpc_kcs_send(astlpc, 0x2))
+	if (!mctp_astlpc_kcs_send(astlpc, cmd_rx_complete))
 		astlpc->layout.rx.state = buffer_state_released;
 
 	hdr = mctp_pktbuf_hdr(pkt);
@@ -1141,11 +1148,11 @@
 	int rc;
 
 	if (astlpc->layout.rx.state == buffer_state_prepared)
-		if (!mctp_astlpc_kcs_send(astlpc, 0x2))
+		if (!mctp_astlpc_kcs_send(astlpc, cmd_rx_complete))
 			astlpc->layout.rx.state = buffer_state_released;
 
 	if (astlpc->layout.tx.state == buffer_state_prepared)
-		if (!mctp_astlpc_kcs_send(astlpc, 0x1))
+		if (!mctp_astlpc_kcs_send(astlpc, cmd_tx_begin))
 			astlpc->layout.tx.state = buffer_state_released;
 
 	rc = mctp_astlpc_kcs_read(astlpc, MCTP_ASTLPC_KCS_REG_STATUS, &status);
@@ -1167,17 +1174,18 @@
 
 	astlpc_prdebug(astlpc, "%s: data: 0x%hhx", __func__, data);
 
-	if (!astlpc->proto->version && !(data == 0x0 || data == 0xff)) {
+	if (!astlpc->proto->version &&
+	    !(data == cmd_initialise || data == cmd_dummy_value)) {
 		astlpc_prwarn(astlpc, "Invalid message for binding state: 0x%x",
 			      data);
 		return 0;
 	}
 
 	switch (data) {
-	case 0x0:
+	case cmd_initialise:
 		mctp_astlpc_init_channel(astlpc);
 		break;
-	case 0x1:
+	case cmd_tx_begin:
 		if (astlpc->layout.rx.state != buffer_state_released) {
 			astlpc_prerr(
 				astlpc,
@@ -1187,7 +1195,7 @@
 		}
 		mctp_astlpc_rx_start(astlpc);
 		break;
-	case 0x2:
+	case cmd_rx_complete:
 		if (astlpc->layout.tx.state != buffer_state_released) {
 			astlpc_prerr(
 				astlpc,
@@ -1197,7 +1205,7 @@
 		}
 		mctp_astlpc_tx_complete(astlpc);
 		break;
-	case 0xff:
+	case cmd_dummy_value:
 		/* No responsibilities for the BMC on 0xff */
 		if (astlpc->mode == MCTP_BINDING_ASTLPC_MODE_HOST) {
 			rc = mctp_astlpc_update_channel(astlpc, status);
@@ -1211,7 +1219,7 @@
 
 	/* Handle silent loss of bmc-ready */
 	if (astlpc->mode == MCTP_BINDING_ASTLPC_MODE_HOST) {
-		if (!(status & KCS_STATUS_BMC_READY && data == 0xff))
+		if (!(status & KCS_STATUS_BMC_READY && data == cmd_dummy_value))
 			return mctp_astlpc_update_channel(astlpc, status);
 	}