Send scan code to host when power button is pressed/released.

But only if the system is in S0.

Approved at internal gerrit: 11595.

BUG=none
TEST=tested on bds.

chip/lm4/power_button.c

@@ -7,6 +7,7 @@
 
 #include "console.h"
 #include "gpio.h"
+#include "keyboard.h"
 #include "power_button.h"
 #include "task.h"
 #include "timer.h"
@@ -63,6 +64,11 @@ static void lid_switch_isr(void)
  *   PWRBTN#   ---  ---------           ----
  *    to PCH     |__|       |___________|
  *                t0    t1    held down
+ *
+ *   scan code   |                      |
+ *    to host    v                      v
+ *     @S0   make code             break code
+ *
  */
 static void set_pwrbtn_to_pch(int high)
 {
@@ -124,15 +130,11 @@ static void power_button_isr(void)
 	if (!gpio_get_level(GPIO_POWER_BUTTONn)) {
 		/* pressed */
 		pwrbtn_sm_start();
-		/* TODO: implement after chip/lm4/x86_power.c is completed. */
-		/* if system is in S5, power_on_system()
-		 * elif system is in S3, resume_system()
-		 * else S0 i8042_send_host(make_code); */
+		keyboard_set_power_button(1);
 	} else {
 		/* released */
 		pwrbtn_sm_stop();
-		/* TODO: implement after chip/lm4/x86_power.c is completed. */
-		/* if system in S0, i8042_send_host(break_code); */
+		keyboard_set_power_button(0);
 	}
 }
 

common/keyboard.c

@@ -13,6 +13,8 @@
 #include "timer.h"
 #include "uart.h"
 #include "util.h"
+#include "x86_power.h"
+
 
 #define KEYBOARD_DEBUG 1
 
@@ -36,6 +38,7 @@ static uint8_t controller_ram[0x20] = {
   I8042_XLATE | I8042_AUX_DIS | I8042_KBD_DIS,
   /* 0x01 - 0x1f are controller RAM */
 };
+static int power_button_pressed = 0;
 
 /*
  * Scancode settings
@@ -106,6 +109,17 @@ static uint16_t scancode_set2[CROS_ROW_NUM][CROS_COL_NUM] = {
 };
 
 
+/* change to set 1 if the I8042_XLATE flag is set. */
+static enum scancode_set_list acting_code_set(enum scancode_set_list set) {
+  if (controller_ram[0] & I8042_XLATE) {
+    /* If the keyboard translation is enabled,
+     * then always generates set 1. */
+    return SCANCODE_SET_1;
+  }
+  return set;
+}
+
+
 static enum ec_error_list matrix_callback(
     int8_t row, int8_t col, int8_t pressed,
     enum scancode_set_list code_set, uint8_t *scan_code, int32_t* len) {
@@ -122,11 +136,7 @@ static enum ec_error_list matrix_callback(
 
   *len = 0;
 
-  if (controller_ram[0] & I8042_XLATE) {
-    /* If the keyboard translation is enabled,
-     * then always generates set 1. */
-    code_set = SCANCODE_SET_1;
-  }
+  code_set = acting_code_set(code_set);
 
   switch (code_set) {
   case SCANCODE_SET_1:
@@ -516,6 +526,32 @@ int handle_keyboard_command(uint8_t command, uint8_t *output) {
 }
 
 
+void keyboard_set_power_button(int pressed)
+{
+	enum scancode_set_list code_set;
+	enum ec_error_list ret;
+	uint8_t code[2][2][3] = {
+		{  /* set 1 */
+			{0xe0, 0xde},        /* break */
+			{0xe0, 0x5e},        /* make */
+		}, {  /* set 2 */
+			{0xe0, 0xf0, 0x37},  /* break */
+			{0xe0, 0x37},        /* make */
+		}
+	};
+
+	power_button_pressed = pressed;
+
+	if (x86_power_in_S0()) {
+		code_set = acting_code_set(scancode_set);
+		ret = i8042_send_to_host(
+		    (code_set == SCANCODE_SET_2 && !pressed) ? 3 : 2,
+		    code[code_set - SCANCODE_SET_1][pressed]);
+		ASSERT(ret == EC_SUCCESS);
+	}
+}
+
+
 static int command_codeset(int argc, char **argv)
 {
 	int set;

common/x86_power.c

@@ -205,6 +205,12 @@ int x86_power_init(void)
 	return EC_SUCCESS;
 }
 
+/*****************************************************************************/
+int x86_power_in_S0(void) {
+	return state == X86_S0;
+}
+
+
 /*****************************************************************************/
 /* Task function */
 

include/keyboard.h

@@ -50,6 +50,11 @@ int handle_keyboard_data(uint8_t data, uint8_t *output);
 int handle_keyboard_command(uint8_t command, uint8_t *output);
 
 
+/* Send make/break code of power button to host.
+ */
+void keyboard_set_power_button(int pressed);
+
+
 /* Register the board-specific keyboard matrix translation function.
  * The callback function accepts col/row and returns the scan code.
  *

include/x86_power.h

@@ -17,4 +17,8 @@ int x86_power_init(void);
 /* Interrupt handler for input GPIOs */
 void x86_power_interrupt(enum gpio_signal signal);
 
+/* Returns true if the system is in S0. */
+int x86_power_in_S0(void);
+
+
 #endif  /* __CROS_EC_X86_POWER_H */