PS874x: Split PS8740 and PS8743

Split ps874x.[ch] into ps8740.[ch] and ps8743.[ch]
since we need to support both at runtime for Dalboz.

I left PS8742 in ps8740.[ch] since it is not very different.

BUG=b:153454399
BRANCH=none
TEST=make -j buildall

Signed-off-by: Edward Hill <ecgh@chromium.org>
Change-Id: I92b02e08f377d1781c130a0bbe1482a936ad7a4d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2151647
Reviewed-by: Denis Brockus <dbrockus@chromium.org>
Commit-Queue: Denis Brockus <dbrockus@chromium.org>

1 files changed, 124 insertions, 0 deletions

diff --git a/driver/usb_mux/ps8740.c b/driver/usb_mux/ps8740.c
new file mode 100644
index 0000000000..b99c107610
--- /dev/null
+++ b/driver/usb_mux/ps8740.c
@@ -0,0 +1,124 @@
+/* Copyright 2020 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.
+ *
+ * Parade PS8740 (and PS8742)
+ * USB Type-C Redriving Switch for USB Host / DisplayPort.
+ */
+
+#include "common.h"
+#include "i2c.h"
+#include "ps8740.h"
+#include "usb_mux.h"
+#include "util.h"
+
+int ps8740_read(const struct usb_mux *me, uint8_t reg, int *val)
+{
+	return i2c_read8(me->i2c_port, me->i2c_addr_flags,
+			 reg, val);
+}
+
+int ps8740_write(const struct usb_mux *me, uint8_t reg, uint8_t val)
+{
+	return i2c_write8(me->i2c_port, me->i2c_addr_flags,
+			  reg, val);
+}
+
+static int ps8740_init(const struct usb_mux *me)
+{
+	int id1;
+	int id2;
+	int res;
+
+	/* Reset chip back to power-on state */
+	res = ps8740_write(me, PS8740_REG_MODE, PS8740_MODE_POWER_DOWN);
+	if (res)
+		return res;
+
+	/*
+	 * Verify chip ID registers.
+	 */
+	res = ps8740_read(me, PS8740_REG_CHIP_ID1, &id1);
+	if (res)
+		return res;
+
+	res  = ps8740_read(me, PS8740_REG_CHIP_ID2, &id2);
+	if (res)
+		return res;
+
+	if (id1 != PS8740_CHIP_ID1 || id2 != PS8740_CHIP_ID2)
+		return EC_ERROR_UNKNOWN;
+
+	/*
+	 * Verify revision ID registers.
+	 */
+	res = ps8740_read(me, PS8740_REG_REVISION_ID1, &id1);
+	if (res)
+		return res;
+
+	res = ps8740_read(me, PS8740_REG_REVISION_ID2, &id2);
+	if (res)
+		return res;
+
+	if (id1 != PS8740_REVISION_ID1)
+		return EC_ERROR_UNKNOWN;
+	/* PS8740 may have REVISION_ID2 as 0xa or 0xb */
+	if (id2 != PS8740_REVISION_ID2_0 && id2 != PS8740_REVISION_ID2_1)
+		return EC_ERROR_UNKNOWN;
+
+	return EC_SUCCESS;
+}
+
+/* Writes control register to set switch mode */
+static int ps8740_set_mux(const struct usb_mux *me, mux_state_t mux_state)
+{
+	uint8_t reg = 0;
+
+	if (mux_state & USB_PD_MUX_USB_ENABLED)
+		reg |= PS8740_MODE_USB_ENABLED;
+	if (mux_state & USB_PD_MUX_DP_ENABLED)
+		reg |= PS8740_MODE_DP_ENABLED;
+	if (mux_state & USB_PD_MUX_POLARITY_INVERTED)
+		reg |= PS8740_MODE_POLARITY_INVERTED;
+
+	return ps8740_write(me, PS8740_REG_MODE, reg);
+}
+
+/* Reads control register and updates mux_state accordingly */
+static int ps8740_get_mux(const struct usb_mux *me, mux_state_t *mux_state)
+{
+	int reg;
+	int res;
+
+	res = ps8740_read(me, PS8740_REG_STATUS, &reg);
+	if (res)
+		return res;
+
+	*mux_state = 0;
+	if (reg & PS8740_STATUS_USB_ENABLED)
+		*mux_state |= USB_PD_MUX_USB_ENABLED;
+	if (reg & PS8740_STATUS_DP_ENABLED)
+		*mux_state |= USB_PD_MUX_DP_ENABLED;
+	if (reg & PS8740_STATUS_POLARITY_INVERTED)
+		*mux_state |= USB_PD_MUX_POLARITY_INVERTED;
+
+	return EC_SUCCESS;
+}
+
+/* Tune USB Tx/Rx Equalization */
+int ps8740_tune_usb_eq(int port, uint8_t tx, uint8_t rx)
+{
+	int ret;
+	const struct usb_mux *me = &usb_muxes[port];
+
+	ret = ps8740_write(me, PS8740_REG_USB_EQ_TX, tx);
+	ret |= ps8740_write(me, PS8740_REG_USB_EQ_RX, rx);
+
+	return ret;
+}
+
+const struct usb_mux_driver ps8740_usb_mux_driver = {
+	.init = ps8740_init,
+	.set = ps8740_set_mux,
+	.get = ps8740_get_mux,
+};