[PATCH v3 09/14] mux: Add Pericom PI3USB30532 Type-C mux driver

[Hans de Goede]

Add a driver for the Pericom PI3USB30532 Type-C cross switch /
mux chip found on some devices with a Type-C port.

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
Changes in v2:
-Adjust for new MUX_TYPEC_foo state defines
-Add MAINTAINERS entry
-Various code-style fixes

Changes in v3:
-Use new init_as_is mux flag
-Adjust for updated MUX_TYPEC_* defines
---
 MAINTAINERS               |  5 +++
 drivers/mux/Kconfig       | 10 ++++++
 drivers/mux/Makefile      |  2 ++
 drivers/mux/pi3usb30532.c | 92 +++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 109 insertions(+)
 create mode 100644 drivers/mux/pi3usb30532.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 6cfa0e5f2d2b..5c844fd3a23c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9181,6 +9181,11 @@ M:	Hans de Goede <hdegoede@xxxxxxxxxx>
 S:	Maintained
 F:	drivers/mux/intel-cht-usb-mux.c
 
+MULTIPLEXER SUBSYSTEM PI3USB30532 DRIVER
+M:	Hans de Goede <hdegoede@xxxxxxxxxx>
+S:	Maintained
+F:	drivers/mux/pi3usb30532.c
+
 MULTISOUND SOUND DRIVER
 M:	Andrew Veliath <andrewtv@xxxxxxx>
 S:	Maintained
diff --git a/drivers/mux/Kconfig b/drivers/mux/Kconfig
index ebc04ae7ff30..f94660229d20 100644
--- a/drivers/mux/Kconfig
+++ b/drivers/mux/Kconfig
@@ -58,4 +58,14 @@ config MUX_MMIO
 	  To compile the driver as a module, choose M here: the module will
 	  be called mux-mmio.
 
+config MUX_PI3USB30532
+	tristate "Pericom PI3USB30532 Type-C cross switch driver"
+	depends on I2C
+	help
+	  This driver adds support for the Pericom PI3USB30532 Type-C cross
+	  switch / mux chip found on some devices with a Type-C port.
+
+	  To compile the driver as a module, choose M here: the module will
+	  be called mux-pi3usb30532.
+
 endmenu
diff --git a/drivers/mux/Makefile b/drivers/mux/Makefile
index 6cf41be2754f..df381c219708 100644
--- a/drivers/mux/Makefile
+++ b/drivers/mux/Makefile
@@ -7,9 +7,11 @@ mux-adg792a-objs		:= adg792a.o
 mux-gpio-objs			:= gpio.o
 mux-intel-cht-usb-mux-objs	:= intel-cht-usb-mux.o
 mux-mmio-objs			:= mmio.o
+mux-pi3usb30532-objs		:= pi3usb30532.o
 
 obj-$(CONFIG_MULTIPLEXER)		+= mux-core.o
 obj-$(CONFIG_MUX_ADG792A)		+= mux-adg792a.o
 obj-$(CONFIG_MUX_GPIO)			+= mux-gpio.o
 obj-$(CONFIG_MUX_INTEL_CHT_USB_MUX)	+= mux-intel-cht-usb-mux.o
 obj-$(CONFIG_MUX_MMIO)			+= mux-mmio.o
+obj-$(CONFIG_MUX_PI3USB30532)		+= mux-pi3usb30532.o
diff --git a/drivers/mux/pi3usb30532.c b/drivers/mux/pi3usb30532.c
new file mode 100644
index 000000000000..13c7c4ec0047
--- /dev/null
+++ b/drivers/mux/pi3usb30532.c
@@ -0,0 +1,92 @@
+/*
+ * Pericom PI3USB30532 Type-C cross switch / mux driver
+ *
+ * Copyright (c) 2017 Hans de Goede <hdegoede@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation, or (at your option)
+ * any later version.
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mux/driver.h>
+#include <linux/mux/usb.h>
+
+#define PI3USB30532_CONF			0x00
+
+#define PI3USB30532_CONF_OPEN			0x00
+#define PI3USB30532_CONF_SWAP			0x01
+#define PI3USB30532_CONF_4LANE_DP		0x02
+#define PI3USB30532_CONF_USB3			0x04
+#define PI3USB30532_CONF_USB3_AND_2LANE_DP	0x06
+
+static int pi3usb30532_set_mux(struct mux_control *mux, int state)
+{
+	struct i2c_client *i2c = to_i2c_client(mux->chip->dev.parent);
+	u8 conf = PI3USB30532_CONF_OPEN;
+
+	if (state == MUX_IDLE_DISCONNECT)
+		return i2c_smbus_write_byte_data(i2c, PI3USB30532_CONF, conf);
+
+	switch (state & ~MUX_TYPEC_POLARITY_INV) {
+	case MUX_TYPEC_USB:
+		conf = PI3USB30532_CONF_USB3;
+		break;
+	case MUX_TYPEC_USB_AND_DP:
+		conf = PI3USB30532_CONF_USB3_AND_2LANE_DP;
+		break;
+	case MUX_TYPEC_DP:
+		conf = PI3USB30532_CONF_4LANE_DP;
+		break;
+	}
+
+	if (state & MUX_TYPEC_POLARITY_INV)
+		conf |= PI3USB30532_CONF_SWAP;
+
+	return i2c_smbus_write_byte_data(i2c, PI3USB30532_CONF, conf);
+}
+
+static const struct mux_control_ops pi3usb30532_ops = {
+	.set = pi3usb30532_set_mux,
+};
+
+static int pi3usb30532_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct mux_chip *mux_chip;
+
+	mux_chip = devm_mux_chip_alloc(dev, 1, 0);
+	if (IS_ERR(mux_chip))
+		return PTR_ERR(mux_chip);
+
+	mux_chip->ops = &pi3usb30532_ops;
+	mux_chip->mux[0].idle_state = MUX_IDLE_DISCONNECT;
+	/* Keep initial state as is, for e.g. booting from an USB disk */
+	mux_chip->mux[0].init_as_is = true;
+	mux_chip->mux[0].states = MUX_TYPEC_STATES;
+
+	return devm_mux_chip_register(dev, mux_chip);
+}
+
+static const struct i2c_device_id pi3usb30532_table[] = {
+	{ "pi3usb30532" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, pi3usb30532_table);
+
+static struct i2c_driver pi3usb30532_driver = {
+	.driver = {
+		.name = "pi3usb30532",
+	},
+	.probe_new = pi3usb30532_probe,
+	.id_table = pi3usb30532_table,
+};
+
+module_i2c_driver(pi3usb30532_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Pericom PI3USB30532 Type-C mux driver");
+MODULE_LICENSE("GPL");
-- 
2.14.1