common: lightbar: put multiple commands under i2c_lock

If other i2c traffic happens around the time the light bar is
initialized, the i2c bus is wedged.

Instead of waiting 500ms in the motion task loop for the tap sequence to
complete, set under i2c lock the lp power and init sequence.

BRANCH=smaug, samus
BUG=chrome-os-partner:45223
TEST=With msleep(500) removed and With lb_power + lb_init + 100ms, I don't see the wedge at TAP
sequence.

Change-Id: I931eb25bcc5e3237b6c569f2330f72f9fc415964
Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/299543
Reviewed-by: Bill Richardson <wfrichar@google.com>

1 files changed, 37 insertions, 16 deletions

diff --git a/common/lb_common.c b/common/lb_common.c
index 9a8c4a666e..da6ea95739 100644
--- a/common/lb_common.c
+++ b/common/lb_common.c
@@ -101,6 +101,7 @@
 
 /* Console output macros */
 #define CPUTS(outstr) cputs(CC_LIGHTBAR, outstr)
+#define CPRINTF(format, args...) cprintf(CC_LIGHTBAR, format, ## args)
 #define CPRINTS(format, args...) cprints(CC_LIGHTBAR, format, ## args)
 
 /******************************************************************************/
@@ -114,16 +115,24 @@ static const uint8_t i2c_addr[] = { 0x54, 0x56 };
 
 static inline void controller_write(int ctrl_num, uint8_t reg, uint8_t val)
 {
+	uint8_t buf[2];
+
+	buf[0] = reg;
+	buf[1] = val;
 	ctrl_num = ctrl_num % ARRAY_SIZE(i2c_addr);
-	i2c_write8(I2C_PORT_LIGHTBAR, i2c_addr[ctrl_num], reg, val);
+	i2c_xfer(I2C_PORT_LIGHTBAR, i2c_addr[ctrl_num], buf, 2, 0, 0,
+		 I2C_XFER_SINGLE);
 }
 
 static inline uint8_t controller_read(int ctrl_num, uint8_t reg)
 {
-	int val = 0;
+	uint8_t buf[1];
+	int rv;
+
 	ctrl_num = ctrl_num % ARRAY_SIZE(i2c_addr);
-	i2c_read8(I2C_PORT_LIGHTBAR, i2c_addr[ctrl_num], reg, &val);
-	return val;
+	rv = i2c_xfer(I2C_PORT_LIGHTBAR, i2c_addr[ctrl_num], &reg, 1, buf, 1,
+		      I2C_XFER_SINGLE);
+	return rv ? 0 : buf[0];
 }
 
 /******************************************************************************/
@@ -189,15 +198,6 @@ static const struct initdata_s init_vals[] = {
 	{0x1a, 0x00},				/* current for LED 1 (green) */
 };
 
-static void set_from_array(const struct initdata_s *data, int count)
-{
-	int i;
-	for (i = 0; i < count; i++) {
-		controller_write(0, data[i].reg, data[i].val);
-		controller_write(1, data[i].reg, data[i].val);
-	}
-}
-
 /* Controller register lookup tables. */
 static const uint8_t led_to_ctrl[] = { 1, 1, 0, 0 };
 #ifdef BOARD_BDS
@@ -242,9 +242,11 @@ static void setrgb(int led, int red, int green, int blue)
 	current[led][2] = blue;
 	ctrl = led_to_ctrl[led];
 	bank = led_to_isc[led];
+	i2c_lock(I2C_PORT_LIGHTBAR, 1);
 	controller_write(ctrl, bank, scale(blue, MAX_BLUE));
 	controller_write(ctrl, bank+1, scale(red, MAX_RED));
 	controller_write(ctrl, bank+2, scale(green, MAX_GREEN));
+	i2c_lock(I2C_PORT_LIGHTBAR, 0);
 }
 
 /* LEDs are numbered 0-3, RGB values should be in 0-255.
@@ -289,10 +291,21 @@ uint8_t lb_get_brightness(void)
 }
 
 /* Initialize the controller ICs after reset */
-void lb_init(void)
+void lb_init(int use_lock)
 {
-	CPRINTS("LB_init_vals");
-	set_from_array(init_vals, ARRAY_SIZE(init_vals));
+	int i;
+
+	CPRINTF("[%T LB_init_vals ");
+	for (i = 0; i < ARRAY_SIZE(init_vals); i++) {
+		CPRINTF("%c", '0' + i % 10);
+		if (use_lock)
+			i2c_lock(I2C_PORT_LIGHTBAR, 1);
+		controller_write(0, init_vals[i].reg, init_vals[i].val);
+		controller_write(1, init_vals[i].reg, init_vals[i].val);
+		if (use_lock)
+			i2c_lock(I2C_PORT_LIGHTBAR, 0);
+	}
+	CPRINTF("]\n");
 	memset(current, 0, sizeof(current));
 }
 
@@ -300,16 +313,20 @@ void lb_init(void)
 void lb_off(void)
 {
 	CPRINTS("LB_off");
+	i2c_lock(I2C_PORT_LIGHTBAR, 1);
 	controller_write(0, 0x01, 0x00);
 	controller_write(1, 0x01, 0x00);
+	i2c_lock(I2C_PORT_LIGHTBAR, 0);
 }
 
 /* Come out of standby mode. */
 void lb_on(void)
 {
 	CPRINTS("LB_on");
+	i2c_lock(I2C_PORT_LIGHTBAR, 1);
 	controller_write(0, 0x01, 0x20);
 	controller_write(1, 0x01, 0x20);
+	i2c_lock(I2C_PORT_LIGHTBAR, 0);
 }
 
 static const uint8_t dump_reglist[] = {
@@ -331,13 +348,17 @@ void lb_hc_cmd_dump(struct ec_response_lightbar *out)
 	for (i = 0; i < ARRAY_SIZE(dump_reglist); i++) {
 		reg = dump_reglist[i];
 		out->dump.vals[i].reg = reg;
+		i2c_lock(I2C_PORT_LIGHTBAR, 1);
 		out->dump.vals[i].ic0 = controller_read(0, reg);
 		out->dump.vals[i].ic1 = controller_read(1, reg);
+		i2c_lock(I2C_PORT_LIGHTBAR, 0);
 	}
 }
 
 /* Helper for host command to write controller registers directly */
 void lb_hc_cmd_reg(const struct ec_params_lightbar *in)
 {
+	i2c_lock(I2C_PORT_LIGHTBAR, 1);
 	controller_write(in->reg.ctrl, in->reg.reg, in->reg.value);
+	i2c_lock(I2C_PORT_LIGHTBAR, 0);
 }