accel: clapper: glimmer: Add support for accelerometer interrupt.

Adding in support for accelerometer interrupt for use currently
in clapper and glimmer. This is disabled by default and can
be enabled with CONFIG_ACCEL_INTERRUPTS.

BUG=none
BRANCH=rambi
TEST=Manual test on a glimmer using accelint console command.

On console enter:
accelint 0 32
When you tap the lid, it should fire the interrupt and print msg
to console.

accelint 1 32
Tap the base and it will fire another interrupt.

Change-Id: I0329112fdcae3c8adc0ca07e74fef7a591d4b9a1
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/190099
Reviewed-by: Randall Spangler <rspangler@chromium.org>

11 files changed, 196 insertions, 13 deletions

diff --git a/board/clapper/board.c b/board/clapper/board.c
index 63ad85b2a1..7b73cddbe2 100644
--- a/board/clapper/board.c
+++ b/board/clapper/board.c
@@ -72,6 +72,10 @@ const struct gpio_info gpio_list[] = {
 	 button_interrupt},
 	{"BUTTON_VOLUME_UP_L",   LM4_GPIO_B, (1<<0), GPIO_INT_BOTH,
 	 button_interrupt},
+	{"ACCEL_INT_LID",        LM4_GPIO_F, (1<<2), GPIO_INT_RISING,
+	 accel_int_lid},
+	{"ACCEL_INT_BASE",       LM4_GPIO_N, (1<<5), GPIO_INT_RISING,
+	 accel_int_base},
 
 	/* Other inputs */
 	{"BOARD_VERSION1",       LM4_GPIO_Q, (1<<5), GPIO_INPUT, NULL},
@@ -88,8 +92,6 @@ const struct gpio_info gpio_list[] = {
 	{"PP1000_S0IX_PGOOD",    LM4_GPIO_H, (1<<6), GPIO_INPUT, NULL},
 	{"USB1_OC_L",            LM4_GPIO_E, (1<<7), GPIO_INPUT, NULL},
 	{"USB2_OC_L",            LM4_GPIO_E, (1<<0), GPIO_INPUT, NULL},
-	{"ACCEL_INT0",           LM4_GPIO_F, (1<<2), GPIO_INPUT, NULL},
-	{"ACCEL_INT1",           LM4_GPIO_N, (1<<5), GPIO_INPUT, NULL},
 
 	/* Outputs; all unasserted by default except for reset signals */
 	{"CPU_PROCHOT",          LM4_GPIO_B, (1<<5), GPIO_OUT_LOW, NULL},
diff --git a/board/clapper/board.h b/board/clapper/board.h
index 85de78ed2c..58ea892eb0 100644
--- a/board/clapper/board.h
+++ b/board/clapper/board.h
@@ -89,6 +89,8 @@ enum gpio_signal {
 	GPIO_UART0_RX,             /* UART0 RX input */
 	GPIO_BUTTON_VOLUME_DOWN_L, /* Volume down button */
 	GPIO_BUTTON_VOLUME_UP_L,   /* Volume up button */
+	GPIO_ACCEL_INT_LID,        /* Accelerometer interrupt lid */
+	GPIO_ACCEL_INT_BASE,       /* Accelerometer interrupt base */
 
 	/* Other inputs */
 	GPIO_BOARD_VERSION1,       /* Board version stuffing resistor 1 */
@@ -102,8 +104,6 @@ enum gpio_signal {
 	GPIO_PP1000_S0IX_PGOOD,    /* Power good on 1.00V (S0iX supplies) */
 	GPIO_USB1_OC_L,            /* USB port overcurrent warning */
 	GPIO_USB2_OC_L,            /* USB port overcurrent warning */
-	GPIO_ACCEL_INT0,           /* Accelerometer interrupt 0 */
-	GPIO_ACCEL_INT1,           /* Accelerometer interrupt 1 */
 
 	/* Outputs */
 	GPIO_CPU_PROCHOT,          /* Force CPU to think it's overheated */
diff --git a/board/glimmer/board.c b/board/glimmer/board.c
index 9b7a723a8e..6aa36cb277 100644
--- a/board/glimmer/board.c
+++ b/board/glimmer/board.c
@@ -88,6 +88,10 @@ const struct gpio_info gpio_list[] = {
 	 button_interrupt},
 	{"BUTTON_VOLUME_UP_L",   LM4_GPIO_B, (1<<0), GPIO_INT_BOTH,
 	 button_interrupt},
+	{"ACCEL_INT_LID",        LM4_GPIO_F, (1<<2), GPIO_INT_RISING,
+	 accel_int_lid},
+	{"ACCEL_INT_BASE",       LM4_GPIO_N, (1<<5), GPIO_INT_RISING,
+	 accel_int_base},
 
 	/* Other inputs */
 	{"BOARD_VERSION1",       LM4_GPIO_Q, (1<<5), GPIO_INPUT, NULL},
diff --git a/board/glimmer/board.h b/board/glimmer/board.h
index 16bf39b3a0..9e10dfba5c 100644
--- a/board/glimmer/board.h
+++ b/board/glimmer/board.h
@@ -93,6 +93,8 @@ enum gpio_signal {
 	GPIO_UART0_RX,             /* UART0 RX input */
 	GPIO_BUTTON_VOLUME_DOWN_L, /* Volume down button */
 	GPIO_BUTTON_VOLUME_UP_L,   /* Volume up button */
+	GPIO_ACCEL_INT_LID,        /* Accelerometer interrupt lid */
+	GPIO_ACCEL_INT_BASE,       /* Accelerometer interrupt base */
 
 	/* Other inputs */
 	GPIO_BOARD_VERSION1,       /* Board version stuffing resistor 1 */
diff --git a/common/console_output.c b/common/console_output.c
index 4c6dde279c..b9db75c7fd 100644
--- a/common/console_output.c
+++ b/common/console_output.c
@@ -32,6 +32,7 @@ static uint32_t channel_mask_saved = CC_DEFAULT;
  */
 static const char * const channel_names[] = {
 	"command",
+	"accel",
 	"charger",
 	"chipset",
 	"clock",
diff --git a/common/motion_sense.c b/common/motion_sense.c
index 7c7b8a55b5..651215ef34 100644
--- a/common/motion_sense.c
+++ b/common/motion_sense.c
@@ -243,6 +243,24 @@ void motion_sense_task(void)
 	}
 }
 
+void accel_int_lid(enum gpio_signal signal)
+{
+	/*
+	 * Print statement is here for testing with console accelint command.
+	 * Remove print statement when interrupt is used for real.
+	 */
+	CPRINTF("[%T Accelerometer wake-up interrupt occurred on lid]\n");
+}
+
+void accel_int_base(enum gpio_signal signal)
+{
+	/*
+	 * Print statement is here for testing with console accelint command.
+	 * Remove print statement when interrupt is used for real.
+	 */
+	CPRINTF("[%T Accelerometer wake-up interrupt occurred on base]\n");
+}
+
 /*****************************************************************************/
 /* Console commands */
 #ifdef CONFIG_CMD_LID_ANGLE
diff --git a/driver/accel_kxcj9.c b/driver/accel_kxcj9.c
index e6e7864175..a95d2c46b7 100644
--- a/driver/accel_kxcj9.c
+++ b/driver/accel_kxcj9.c
@@ -14,6 +14,9 @@
 #include "timer.h"
 #include "util.h"
 
+#define CPUTS(outstr) cputs(CC_ACCEL, outstr)
+#define CPRINTF(format, args...) cprintf(CC_ACCEL, format, ## args)
+
 /* Range of the accelerometers: 2G, 4G, or 8G. */
 static int sensor_range[ACCEL_COUNT] = {KXCJ9_GSEL_2G, KXCJ9_GSEL_2G};
 
@@ -111,6 +114,77 @@ int accel_write_datarate(const enum accel_id id, const int rate)
 	return ret;
 }
 
+#ifdef CONFIG_ACCEL_INTERRUPTS
+int accel_set_interrupt(const enum accel_id id, unsigned int threshold)
+{
+	int ctrl1, tmp, ret;
+
+	/*
+	 * TODO(crosbug.com/p/26884): This driver currently assumes only one
+	 * task can call this function. If this isn't true anymore, need to
+	 * protect with a mutex.
+	 */
+
+	/*
+	 * Read the current status of the control register and disable the
+	 * sensor to allow for changing of critical parameters.
+	 */
+	ret = raw_read8(accel_addr[id], KXCJ9_CTRL1, &ctrl1);
+	if (ret != EC_SUCCESS)
+		return ret;
+	ret = raw_write8(accel_addr[id], KXCJ9_CTRL1, ctrl1 & ~KXCJ9_CTRL1_PC1);
+	if (ret != EC_SUCCESS)
+		return ret;
+
+	/* Set interrupt timer to 1 so it wakes up immediately. */
+	ret = raw_write8(accel_addr[id], KXCJ9_WAKEUP_TIMER, 1);
+	if (ret != EC_SUCCESS)
+		goto error_enable_sensor;
+
+	/*
+	 * Set threshold, note threshold register is in units of 16 counts, so
+	 * first we need to divide by 16 to get the value to send.
+	 */
+	threshold >>= 4;
+	ret = raw_write8(accel_addr[id], KXCJ9_WAKEUP_THRESHOLD, threshold);
+	if (ret != EC_SUCCESS)
+		goto error_enable_sensor;
+
+	/*
+	 * Set interrupt enable register on sensor. Note that once this
+	 * function is called once, the interrupt stays enabled and it is
+	 * only necessary to clear KXCJ9_INT_REL to allow the next interrupt.
+	 */
+	ret = raw_read8(accel_addr[id], KXCJ9_INT_CTRL1, &tmp);
+	if (ret != EC_SUCCESS)
+		goto error_enable_sensor;
+	if (!(tmp & KXCJ9_INT_CTRL1_IEN)) {
+		ret = raw_write8(accel_addr[id], KXCJ9_INT_CTRL1,
+				tmp | KXCJ9_INT_CTRL1_IEN);
+		if (ret != EC_SUCCESS)
+			goto error_enable_sensor;
+	}
+
+	/*
+	 * Clear any pending interrupt on sensor by reading INT_REL register.
+	 * Note: this register latches motion detected above threshold. Once
+	 * latched, no interrupt can occur until this register is cleared.
+	 */
+	ret = raw_read8(accel_addr[id], KXCJ9_INT_REL, &tmp);
+
+error_enable_sensor:
+	/* Re-enable accelerometer. */
+	if (raw_write8(accel_addr[id], KXCJ9_CTRL1, ctrl1 | KXCJ9_CTRL1_PC1) !=
+			EC_SUCCESS) {
+		/* Cannot re-enable accel, print warning and return an error. */
+		CPRINTF("[%T Error trying to enable accelerometer %d]\n", id);
+		return EC_ERROR_UNKNOWN;
+	}
+
+	return ret;
+}
+#endif
+
 int accel_read(enum accel_id id, int *x_acc, int *y_acc, int *z_acc)
 {
 	uint8_t acc[6];
@@ -166,7 +240,7 @@ int accel_read(enum accel_id id, int *x_acc, int *y_acc, int *z_acc)
 int accel_init(enum accel_id id)
 {
 	int ret = EC_SUCCESS;
-	int cnt = 0, ctrl2;
+	int cnt = 0, ctrl1, ctrl2;
 
 	/* Check for valid id. */
 	if (id < 0 || id >= ACCEL_COUNT)
@@ -197,14 +271,37 @@ int accel_init(enum accel_id id)
 		msleep(10);
 	}
 
-	/* Enable accelerometer, 12-bit resolution mode, +/- 2G range.*/
-	ret |= raw_write8(accel_addr[id],  KXCJ9_CTRL1,
-			KXCJ9_CTRL1_PC1 | sensor_resolution[id] |
-			sensor_range[id]);
+#ifdef CONFIG_ACCEL_INTERRUPTS
+	/* Set interrupt polarity to rising edge and keep interrupt disabled. */
+	ret |= raw_write8(accel_addr[id], KXCJ9_INT_CTRL1, KXCJ9_INT_CTRL1_IEA);
+
+	/* Set output data rate for wake-up interrupt function. */
+	ret |= raw_write8(accel_addr[id], KXCJ9_CTRL2, KXCJ9_OWUF_100_0HZ);
+
+	/* Set interrupt to trigger on motion on any axis. */
+	ret |= raw_write8(accel_addr[id], KXCJ9_INT_CTRL2,
+			KXCJ9_INT_SRC2_XNWU | KXCJ9_INT_SRC2_XPWU |
+			KXCJ9_INT_SRC2_YNWU | KXCJ9_INT_SRC2_YPWU |
+			KXCJ9_INT_SRC2_ZNWU | KXCJ9_INT_SRC2_ZPWU);
+
+	/*
+	 * Enable accel interrupts. Note: accels will not initiate an interrupt
+	 * until interrupt enable bit in KXCJ9_INT_CTRL1 is set on the device.
+	 */
+	gpio_enable_interrupt(GPIO_ACCEL_INT_LID);
+	gpio_enable_interrupt(GPIO_ACCEL_INT_BASE);
+#endif
 
 	/* Set output data rate. */
-	ret |= raw_write8(accel_addr[id],  KXCJ9_DATA_CTRL,
-			sensor_datarate[id]);
+	ret |= raw_write8(accel_addr[id], KXCJ9_DATA_CTRL, sensor_datarate[id]);
+
+	/* Set resolution and range and enable sensor. */
+	ctrl1 = sensor_resolution[id] | sensor_range[id]  | KXCJ9_CTRL1_PC1;
+#ifdef CONFIG_ACCEL_INTERRUPTS
+	/* Enable wake up (motion detect) functionality. */
+	ctrl1 |= KXCJ9_CTRL1_WUFE;
+#endif
+	ret = raw_write8(accel_addr[id], KXCJ9_CTRL1, ctrl1);
 
 	return ret;
 }
@@ -213,7 +310,6 @@ int accel_init(enum accel_id id)
 
 /*****************************************************************************/
 /* Console commands */
-
 #ifdef CONFIG_CMD_ACCELS
 static int command_read_accelerometer(int argc, char **argv)
 {
@@ -273,4 +369,33 @@ static int command_write_accelerometer(int argc, char **argv)
 DECLARE_CONSOLE_COMMAND(accelwrite, command_write_accelerometer,
 	"addr reg data",
 	"Write to accelerometer at slave address addr", NULL);
+
+#ifdef CONFIG_ACCEL_INTERRUPTS
+static int command_accelerometer_interrupt(int argc, char **argv)
+{
+	char *e;
+	int id, thresh;
+
+	if (argc != 3)
+		return EC_ERROR_PARAM_COUNT;
+
+	/* First argument is id. */
+	id = strtoi(argv[1], &e, 0);
+	if (*e || id < 0 || id >= ACCEL_COUNT)
+		return EC_ERROR_PARAM1;
+
+	/* Second argument is interrupt threshold. */
+	thresh = strtoi(argv[2], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM2;
+
+	accel_set_interrupt(id, thresh);
+
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(accelint, command_accelerometer_interrupt,
+	"id threshold",
+	"Write interrupt threshold", NULL);
+#endif /* CONFIG_ACCEL_INTERRUPTS */
+
 #endif /* CONFIG_CMD_ACCELS */
diff --git a/driver/accel_kxcj9.h b/driver/accel_kxcj9.h
index 9451421be5..e35386d330 100644
--- a/driver/accel_kxcj9.h
+++ b/driver/accel_kxcj9.h
@@ -129,4 +129,16 @@ int accel_write_resolution(const enum accel_id id, const int res);
  */
 int accel_write_datarate(const enum accel_id id, const int rate);
 
+#ifdef CONFIG_ACCEL_INTERRUPTS
+/**
+ * Setup a one-time accel interrupt. If the threshold is low enough, the
+ * interrupt may trigger due simply to noise and not any real motion. If the
+ * threshold is 0, the interrupt will fire immediately.
+ *
+ * @param id Target accelerometer
+ * @param threshold Threshold for interrupt in units of counts.
+ */
+int accel_set_interrupt(const enum accel_id id, unsigned int threshold);
+#endif
+
 #endif /* __CROS_EC_ACCEL_KXCJ9_H */
diff --git a/include/config.h b/include/config.h
index 224910cce2..aed9085202 100644
--- a/include/config.h
+++ b/include/config.h
@@ -36,9 +36,12 @@
  * BOARD_*, CHIP_*, and CHIP_FAMILY_*.
  */
 
-/* Use to enable EC console functions for calibrating accelerometers. */
+/* Enable EC console functions for calibrating accelerometers. */
 #undef CONFIG_ACCEL_CALIBRATE
 
+/* Enable accelerometer interrupts. */
+#undef CONFIG_ACCEL_INTERRUPTS
+
 /* Specify type of accelerometers attached. */
 #undef CONFIG_ACCEL_KXCJ9
 
diff --git a/include/console.h b/include/console.h
index 41bc9decbd..8106e54f56 100644
--- a/include/console.h
+++ b/include/console.h
@@ -28,6 +28,7 @@ struct console_command {
 enum console_channel {
 	CC_COMMAND = 0,  /* Console command (interactive I/O).  Use this only
 			  * inside a console command routine. */
+	CC_ACCEL,
 	CC_CHARGER,
 	CC_CHIPSET,
 	CC_CLOCK,
diff --git a/include/motion_sense.h b/include/motion_sense.h
index dda02f19f9..08aefbcc0b 100644
--- a/include/motion_sense.h
+++ b/include/motion_sense.h
@@ -8,6 +8,7 @@
 #ifndef __CROS_EC_MOTION_SENSE_H
 #define __CROS_EC_MOTION_SENSE_H
 
+#include "gpio.h"
 #include "math_util.h"
 
 /**
@@ -73,5 +74,19 @@ void motion_get_accel_lid(vector_3_t *v, int adjusted);
 void motion_get_accel_base(vector_3_t *v);
 #endif
 
+/**
+ * Interrupt function for lid accelerometer.
+ *
+ * @param signal GPIO signal that caused interrupt
+ */
+void accel_int_lid(enum gpio_signal signal);
+
+/**
+ * Interrupt function for base accelerometer.
+ *
+ * @param signal GPIO signal that caused interrupt
+ */
+void accel_int_base(enum gpio_signal signal);
+
 
 #endif /* __CROS_EC_MOTION_SENSE_H */