usbc: retimer pi3dpx1207

BUG=b:139428185
BRANCH=none
TEST=verify mode is set correctly when switching devices

Change-Id: Ic9d460a94bb8007f17168ac5237a4dcbc24cfb2b
Signed-off-by: Denis Brockus <dbrockus@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/1900123
Reviewed-by: Edward Hill <ecgh@chromium.org>

1 files changed, 115 insertions, 0 deletions

diff --git a/driver/retimer/pi3dpx1207.c b/driver/retimer/pi3dpx1207.c
new file mode 100644
index 0000000000..f1f1e19b54
--- /dev/null
+++ b/driver/retimer/pi3dpx1207.c
@@ -0,0 +1,115 @@
+/* Copyright 2019 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * PI3DPX1207 retimer.
+ */
+
+#include "pi3dpx1207.h"
+#include "common.h"
+#include "console.h"
+#include "gpio.h"
+#include "i2c.h"
+#include "ioexpander.h"
+#include "usb_mux.h"
+
+#define I2C_MAX_RETRIES 2
+
+/* Stack space is limited, so put the buffer somewhere else */
+static uint8_t buf[PI3DPX1207_NUM_REGISTERS];
+
+static int pi3dpx1207_i2c_write(int i2c_port,
+				uint16_t addr_flags,
+				uint8_t offset,
+				uint8_t val)
+{
+	int rv = EC_SUCCESS;
+	int attempt;
+
+	if (offset >= PI3DPX1207_NUM_REGISTERS)
+		return EC_ERROR_INVAL;
+
+	/*
+	 * PI3DPX1207 does not support device register offset in
+	 * the typical I2C sense. Have to read the values starting
+	 * from 0, modify the byte and then write the block.
+	 *
+	 * NOTE: The device may not respond correctly if it was
+	 * just powered or has gone to sleep.  Allow for retries
+	 * in case this happens.
+	 */
+	if (offset > 0) {
+		attempt = 0;
+		do {
+			attempt++;
+			rv = i2c_xfer(i2c_port, addr_flags,
+				      NULL, 0, buf, offset);
+		} while ((rv != EC_SUCCESS) && (attempt < I2C_MAX_RETRIES));
+	}
+
+	if (rv == EC_SUCCESS) {
+		buf[offset] = val;
+
+		attempt = 0;
+		do {
+			attempt++;
+			rv = i2c_xfer(i2c_port, addr_flags,
+				      buf, offset + 1, NULL, 0);
+		} while ((rv != EC_SUCCESS) && (attempt < I2C_MAX_RETRIES));
+	}
+	return rv;
+}
+
+static int pi3dpx1207_set_mux(int port, mux_state_t mux_state)
+{
+	int rv = EC_SUCCESS;
+	uint8_t mode_val		= PI3DPX1207_MODE_WATCHDOG_EN;
+
+	const int i2c_port		= usb_retimers[port].i2c_port;
+	const uint16_t i2c_addr_flags	= usb_retimers[port].i2c_addr_flags;
+	const int gpio_enable		= usb_retimers[port].gpio_enable;
+	const int gpio_dp_enable	= usb_retimers[port].gpio_dp_enable;
+
+	/* USB */
+	if (mux_state & MUX_USB_ENABLED) {
+		gpio_or_ioex_set_level(gpio_enable, 1);
+		/* USB with DP */
+		if (mux_state & MUX_DP_ENABLED) {
+			gpio_or_ioex_set_level(gpio_dp_enable, 1);
+			mode_val |= (mux_state & MUX_POLARITY_INVERTED)
+					? PI3DPX1207_MODE_CONF_USB_DP_FLIP
+					: PI3DPX1207_MODE_CONF_USB_DP;
+		}
+		/* USB without DP */
+		else {
+			gpio_or_ioex_set_level(gpio_dp_enable, 0);
+			mode_val |= (mux_state & MUX_POLARITY_INVERTED)
+					? PI3DPX1207_MODE_CONF_USB_FLIP
+					: PI3DPX1207_MODE_CONF_USB;
+		}
+	}
+	/* DP without USB */
+	else if (mux_state & MUX_DP_ENABLED) {
+		gpio_or_ioex_set_level(gpio_enable, 1);
+		gpio_or_ioex_set_level(gpio_dp_enable, 1);
+		mode_val |= (mux_state & MUX_POLARITY_INVERTED)
+				? PI3DPX1207_MODE_CONF_DP_FLIP
+				: PI3DPX1207_MODE_CONF_DP;
+	}
+	/* Nothing enabled, power down the retimer */
+	else {
+		gpio_or_ioex_set_level(gpio_enable, 0);
+		gpio_or_ioex_set_level(gpio_dp_enable, 0);
+		return EC_SUCCESS;
+	}
+
+	/* Write the retimer config byte */
+	rv = pi3dpx1207_i2c_write(i2c_port, i2c_addr_flags,
+				  PI3DPX1207_MODE_OFFSET,
+				  mode_val);
+	return rv;
+}
+
+const struct usb_retimer_driver pi3dpx1207_usb_retimer = {
+	.set = pi3dpx1207_set_mux,
+};