GPIO/IOEX/eSPI: Give different IO signals unique values

There are 3 different IO signal types used by the EC.
Ensure they each use a unique range of values so we can tell them apart.
1) Local GPIO => 0 to 0x0FFF
2) IO expander GPIO => 0x1000 to 0x1FFF
3) eSPI virtual wire signals => 0x2000 to 0x2FFF

BUG=b:138600691
BRANCH=none
TEST=IO expander signals still work on Trembyle

Change-Id: I63fadb4bb4573ed3dd121c24e3bd40a00873e29f
Signed-off-by: Edward Hill <ecgh@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1854778
Reviewed-by: Denis Brockus <dbrockus@chromium.org>

3 files changed, 41 insertions, 7 deletions

diff --git a/include/espi.h b/include/espi.h
index 2795f9aacb..6d4de73330 100644
--- a/include/espi.h
+++ b/include/espi.h
@@ -12,8 +12,9 @@
 
 /* Signal through VW */
 enum espi_vw_signal {
-	VW_SIGNAL_BASE = GPIO_COUNT,
-	VW_SLP_S3_L,			/* index 02h (In)  */
+	/* The first valid VW signal is 0x2000 */
+	VW_SIGNAL_START = IOEX_LIMIT + 1,
+	VW_SLP_S3_L = VW_SIGNAL_START,	/* index 02h (In)  */
 	VW_SLP_S4_L,
 	VW_SLP_S5_L,
 	VW_SUS_STAT_L,			/* index 03h (In)  */
@@ -37,10 +38,12 @@ enum espi_vw_signal {
 	VW_SLP_A_L,
 	VW_SLP_LAN,                     /* index 42h (In)  */
 	VW_SLP_WLAN,
-	VW_SIGNAL_BASE_END,
+	VW_SIGNAL_END,
+	VW_LIMIT = 0x2FFF
 };
+BUILD_ASSERT(VW_SIGNAL_END < VW_LIMIT);
 
-#define VW_SIGNAL_COUNT (VW_SIGNAL_BASE_END - VW_SIGNAL_BASE - 1)
+#define VW_SIGNAL_COUNT (VW_SIGNAL_END - VW_SIGNAL_START)
 
 /**
  * Set eSPI Virtual-Wire signal to Host
diff --git a/include/gpio_signal.h b/include/gpio_signal.h
index e863b7c415..478e83dca5 100644
--- a/include/gpio_signal.h
+++ b/include/gpio_signal.h
@@ -6,21 +6,44 @@
 #ifndef __CROS_EC_GPIO_SIGNAL_H
 #define __CROS_EC_GPIO_SIGNAL_H
 
+#include "compile_time_macros.h"
+
+/*
+ * There are 3 different IO signal types used by the EC.
+ * Ensure they each use a unique range of values so we can tell them apart.
+ * 1) Local GPIO => 0 to 0x0FFF
+ * 2) IO expander GPIO => 0x1000 to 0x1FFF
+ * 3) eSPI virtual wire signals (defined in include/espi.h) => 0x2000 to 0x2FFF
+ */
+
 #define GPIO(name, pin, flags) GPIO_##name,
 #define UNIMPLEMENTED(name) GPIO_##name,
 #define GPIO_INT(name, pin, flags, signal) GPIO_##name,
 
+#define GPIO_SIGNAL_START 0 /* The first valid GPIO signal is 0 */
+
 enum gpio_signal {
 	#include "gpio.wrap"
-	GPIO_COUNT
+	GPIO_COUNT,
+	/* Ensure that sizeof gpio_signal is large enough for ioex_signal */
+	GPIO_LIMIT = 0x0FFF
 };
+BUILD_ASSERT(GPIO_COUNT < GPIO_LIMIT);
 
 #define IOEX(name, expin, flags) IOEX_##name,
 #define IOEX_INT(name, expin, flags, signal) IOEX_##name,
 
 enum ioex_signal {
+	/* The first valid IOEX signal is 0x1000 */
+	IOEX_SIGNAL_START = GPIO_LIMIT + 1,
+	/* Used to ensure that the first IOEX signal is same as start */
+	__IOEX_PLACEHOLDER = GPIO_LIMIT,
 	#include "gpio.wrap"
-	IOEX_COUNT
+	IOEX_SIGNAL_END,
+	IOEX_LIMIT = 0x1FFF
 };
+BUILD_ASSERT(IOEX_SIGNAL_END < IOEX_LIMIT);
+
+#define IOEX_COUNT (IOEX_SIGNAL_END - IOEX_SIGNAL_START)
 
 #endif /* __CROS_EC_GPIO_SIGNAL_H */
diff --git a/include/ioexpander.h b/include/ioexpander.h
index 150db65750..206b0a390c 100644
--- a/include/ioexpander.h
+++ b/include/ioexpander.h
@@ -148,5 +148,13 @@ int ioex_init(int ioex);
  * @returns name of the given IOEX signal
  */
 const char *ioex_get_name(enum ioex_signal signal);
-#endif /* __CROS_EC_IOEXPANDER_H */
 
+/*
+ * Check if signal is an IO expander signal or GPIO signal.
+ *
+ * @param signal	GPIO or IOEX signal
+ * @return		1 if signal is IOEX else return 0
+ */
+int signal_is_ioex(int signal);
+
+#endif /* __CROS_EC_IOEXPANDER_H */