ipmi: kcs: aspeed: Adapt to new LPC DTS layout

Add check against LPC device v2 compatible string to
ensure that the fixed device tree layout is adopted.
The LPC register offsets are also fixed accordingly.

Signed-off-by: Chia-Wei Wang <chiawei_wang@aspeedtech.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Haiyue Wang <haiyue.wang@linux.intel.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20210319062752.145730-3-andrew@aj.id.au
Signed-off-by: Joel Stanley <joel@jms.id.au>

drivers/char/ipmi/kcs_bmc_aspeed.c

@@ -27,7 +27,6 @@
 
 #define KCS_CHANNEL_MAX     4
 
-/* mapped to lpc-bmc@0 IO space */
 #define LPC_HICR0            0x000
 #define     LPC_HICR0_LPC3E          BIT(7)
 #define     LPC_HICR0_LPC2E          BIT(6)
@@ -52,15 +51,13 @@
 #define LPC_STR1             0x03C
 #define LPC_STR2             0x040
 #define LPC_STR3             0x044
-
-/* mapped to lpc-host@80 IO space */
-#define LPC_HICRB            0x080
+#define LPC_HICRB            0x100
 #define     LPC_HICRB_IBFIF4         BIT(1)
 #define     LPC_HICRB_LPC4E          BIT(0)
-#define LPC_LADR4            0x090
-#define LPC_IDR4             0x094
-#define LPC_ODR4             0x098
-#define LPC_STR4             0x09C
+#define LPC_LADR4            0x110
+#define LPC_IDR4             0x114
+#define LPC_ODR4             0x118
+#define LPC_STR4             0x11C
 
 struct aspeed_kcs_bmc {
 	struct regmap *map;
@@ -348,12 +345,20 @@ static int aspeed_kcs_probe(struct platform_device *pdev)
 	struct device_node *np;
 	int rc;
 
-	np = pdev->dev.of_node;
+	np = dev->of_node->parent;
+	if (!of_device_is_compatible(np, "aspeed,ast2400-lpc-v2") &&
+	    !of_device_is_compatible(np, "aspeed,ast2500-lpc-v2") &&
+	    !of_device_is_compatible(np, "aspeed,ast2600-lpc-v2")) {
+		dev_err(dev, "unsupported LPC device binding\n");
+		return -ENODEV;
+	}
+
+	np = dev->of_node;
 	if (of_device_is_compatible(np, "aspeed,ast2400-kcs-bmc") ||
-			of_device_is_compatible(np, "aspeed,ast2500-kcs-bmc"))
+	    of_device_is_compatible(np, "aspeed,ast2500-kcs-bmc"))
 		kcs_bmc = aspeed_kcs_probe_of_v1(pdev);
 	else if (of_device_is_compatible(np, "aspeed,ast2400-kcs-bmc-v2") ||
-			of_device_is_compatible(np, "aspeed,ast2500-kcs-bmc-v2"))
+		 of_device_is_compatible(np, "aspeed,ast2500-kcs-bmc-v2"))
 		kcs_bmc = aspeed_kcs_probe_of_v2(pdev);
 	else
 		return -EINVAL;