superio/common: Support more than one SuperIO in ACPI

The SuperIO ACPI name was hard-coded to "SIO0".  Allow setting the name
in the device tree so more than one SuperIO can be named.

An upcoming board (purism/librem_l1um_v2) has two SuperIOs - one in the
AST2500 BMC, and a Nuvoton NCT6791D used for hardware monitor, POST
display, etc.

Many boards have references to SIO0 already, so the default name is
still the same for a single SuperIO.

Change-Id: Ibfa6ab7622749e6310ee91530bc3722e8e28d9bb
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/75089
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/superio/common/chip.h

@@ -5,6 +5,9 @@
 
 struct superio_common_config {
 	/* FIXME: Add enter conf/exit conf codes here for SSDT generation */
+	/* Rarely, boards may have more than one SuperIO.  Give each SuperIO a
+	 * unique name for ACPI.  The default is 'SIO0'. */
+	char acpi_name[5];
 };
 
 #endif /* __SUPERIO_COMMON_CHIP_H__ */

src/superio/common/generic.c

@@ -4,6 +4,7 @@
 #include <device/pnp.h>
 #include <acpi/acpigen.h>
 #include <console/console.h>
+#include "chip.h"
 
 static void generic_set_resources(struct device *dev)
 {
@@ -292,6 +293,11 @@ static void generic_ssdt(const struct device *dev)
 
 static const char *generic_acpi_name(const struct device *dev)
 {
+	const struct superio_common_config *cfg = dev->chip_info;
+	if (cfg && cfg->acpi_name[sizeof(cfg->acpi_name)-1] == '\0' &&
+		strlen(cfg->acpi_name) == 4) {
+		return cfg->acpi_name;
+	}
 	return "SIO0";
 }
 #endif