Merge pull request #490 from FrameworkComputer/hx20.i2c_port_workaround

Fixed touchpad cannot work due to i2c bus error

Author: kiram9

board/hx20/ps2mouse.c

@@ -305,7 +305,7 @@ void setup_touchpad(void)
 	/* These are touchpad firmware dependent
 	 * They set the touchpad into the mouse device mode, instead of PTP mode
 	 * And are based on the HID descriptor for our unique device */
-	const static uint16_t cmd[5] = {0x0336, 0x0023, 0x0004, 0x0006};
+	const static uint16_t cmd[4] = {0x0336, 0x0023, 0x0004, 0x0006};
 
 	rv = i2c_write_offset16_block(I2C_PORT_TOUCHPAD,
 									TOUCHPAD_I2C_HID_EP | I2C_FLAG_ADDR16_LITTLE_ENDIAN,
@@ -326,6 +326,7 @@ static int inreport_retries;
 void read_touchpad_in_report(void)
 {
 	int rv = EC_SUCCESS;
+	int need_reset = 0;
 	uint8_t data[128];
 	int xfer_len = 0;
 	int16_t x, y;
@@ -340,6 +341,8 @@ void read_touchpad_in_report(void)
 
 	/*dont trigger disable state during our own transactions*/
 	gpio_disable_interrupt(GPIO_EC_I2C_3_SDA);
+	/* need to disable SOC_TP_INT_L if we need to setup touchpad */
+	gpio_disable_interrupt(GPIO_SOC_TP_INT_L);
 	i2c_set_timeout(I2C_PORT_TOUCHPAD, 25*MSEC);
 	i2c_lock(I2C_PORT_TOUCHPAD, 1);
 	rv = i2c_xfer_unlocked(I2C_PORT_TOUCHPAD,
@@ -349,9 +352,14 @@ void read_touchpad_in_report(void)
 		goto read_failed;
 	xfer_len = (data[1]<<8) + data[0];
 	if (xfer_len == 0) {
-		/* touchpad has reset per i2c-hid-protocol 7.3 */
-		CPRINTS("PS2M Touchpad Reset");
-		goto read_failed;
+		/**
+		 * touchpad has reset per i2c-hid-protocol 7.3
+		 * We need to complete the read protocol to make sure i2c state machine
+		 * is correct.
+		 */
+		CPRINTS("PS2M Touchpad need to reset");
+		xfer_len = 6;
+		need_reset = 1;
 	}
 	xfer_len = MIN(126, xfer_len-2);
 	rv = i2c_xfer_unlocked(I2C_PORT_TOUCHPAD,
@@ -385,7 +393,7 @@ void read_touchpad_in_report(void)
 	}
 	i2c_lock(I2C_PORT_TOUCHPAD, 0);
 	gpio_enable_interrupt(GPIO_EC_I2C_3_SDA);
-
+	gpio_enable_interrupt(GPIO_SOC_TP_INT_L);
 	 if (mouse_state == PS2MSTATE_RESET) {
 		 return;
 	 }
@@ -416,13 +424,13 @@ void read_touchpad_in_report(void)
 		current_pos[1] = x;
 		current_pos[2] = y;
 		send_movement_packet();
-	} else {
-		if (rv == EC_SUCCESS) {
-			CPRINTS("PS2M Unexpected Report ID %d reconfiguring", data[2]);
-			setup_touchpad();
-		}
 	}
 
+	if (need_reset) {
+		CPRINTS("PS2M Unexpected Report ID %d reconfiguring", data[2]);
+		setup_touchpad();
+		need_reset = 0;
+	}
 }
 /*
  * Looking at timing it takes the SOC about 2ms to grab a tp packet from start of

chip/mchp/i2c.c

@@ -80,6 +80,10 @@
 #define CFG_ENABLE	BIT(10) /* enable controller */
 #define CFG_GC_DIS	BIT(14) /* disable general call address */
 #define CFG_PROM_EN BIT(15) /* enable Promiscuous mode */
+#define CFG_FLUSH_SXBUF (16) /* clear slave Tx buffer */
+#define CFG_FLUSH_SRBUF (17) /* clear slave Rx buffer */
+#define CFG_FLUSH_MXBUF (18) /* clear master Tx buffer */
+#define CFG_FLUSH_MRBUF (19) /* clear master Rx buffer */
 #define CFG_ENIDI	BIT(29) /* Enable I2C idle interrupt */
 /* Enable network layer master done interrupt */
 #define CFG_ENMI	BIT(30)
@@ -617,6 +621,21 @@ static int i2c_mtx(int ctrl)
 		cdata[ctrl].transaction_state = I2C_TRANSACTION_OPEN;
 	}
 
+	/* Workaround to revocer the LAB flag error */
+	while (MCHP_I2C_STATUS(ctrl) & STS_LAB) {
+		CPRINTS("I2C%d wSTS LAB error, doing reset!", ctrl);
+		MCHP_I2C_CONFIG(ctrl) |= CFG_FLUSH_MRBUF | CFG_FLUSH_MXBUF |
+					CFG_FLUSH_SRBUF | CFG_FLUSH_SXBUF;
+		reset_controller(ctrl);
+		usleep(1000);
+
+		MCHP_I2C_DATA(ctrl) = cdata[ctrl].slv_addr_8bit;
+		/* Clock out the slave address, sending START bit */
+		MCHP_I2C_CTRL(ctrl) = CTRL_PIN | CTRL_ESO | CTRL_ENI |
+			CTRL_ACK | CTRL_STA;
+		cdata[ctrl].transaction_state = I2C_TRANSACTION_OPEN;
+	}
+
 	for (i = 0; i < cdata[ctrl].out_size; ++i) {
 		rv = wait_byte_done(ctrl, 0xff, 0x00);
 		if (rv) {
@@ -700,6 +719,29 @@ static int i2c_mrx_start(int ctrl)
 		/* address then START */
 		MCHP_I2C_CTRL(ctrl) = u8 | CTRL_PIN;
 	}
+
+	/* Workaround to revocer the LAB flag error */
+	while (MCHP_I2C_STATUS(ctrl) & STS_LAB) {
+		CPRINTS("I2C%d rSTS LAB error, doing reset!", ctrl);
+		MCHP_I2C_CONFIG(ctrl) |= CFG_FLUSH_MRBUF | CFG_FLUSH_MXBUF |
+					CFG_FLUSH_SRBUF | CFG_FLUSH_SXBUF;
+		reset_controller(ctrl);
+		usleep(1000);
+
+		if (cdata[ctrl].transaction_state == I2C_TRANSACTION_OPEN) {
+			cdata[ctrl].flags |= (1ul << 5);
+			/* Repeated-START then address */
+			MCHP_I2C_CTRL(ctrl) = u8;
+		}
+
+		MCHP_I2C_DATA(ctrl) = cdata[ctrl].slv_addr_8bit | 0x01;
+		if (cdata[ctrl].transaction_state == I2C_TRANSACTION_STOPPED) {
+			cdata[ctrl].flags |= (1ul << 6);
+			/* address then START */
+			MCHP_I2C_CTRL(ctrl) = u8 | CTRL_PIN;
+		}
+	}
+
 	cdata[ctrl].transaction_state = I2C_TRANSACTION_OPEN;
 	/* Controller generates START, transmits data(address) capturing
 	 * 9-bits from SDA (8-bit address + (N)Ack bit).
@@ -841,8 +883,10 @@ int chip_i2c_xfer(int port, uint16_t slave_addr_flags,
 
 	cdata[ctrl].flags |= (1ul << 15);
 	/* MCHP wait for STOP to complete */
-	if (cdata[ctrl].xflags & I2C_XFER_STOP)
+	if (cdata[ctrl].xflags & I2C_XFER_STOP) {
+		cdata[ctrl].transaction_state = I2C_TRANSACTION_STOPPED;
 		wait_idle(ctrl);
+	}
 
 	/* Check for error conditions */
 	if (MCHP_I2C_STATUS(ctrl) & (STS_LAB | STS_BER)) {