[PATCH v2 2/2] usb: misc: usb5807: Add driver
From: Mike Looijmans
Date: Mon May 15 2023 - 02:25:45 EST
The USB5807 is a 7-port USB 3.1 hub that can be configured by I2C.
This drivers resets the chip, optionally allows D+/D- lines to be
swapped in the devicetree config, and then sends an ATTACH command to
put the device in operational mode.
Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
---
Changes in v2:
Add regulator support for vddXX supplies
drivers/usb/misc/Kconfig | 9 ++
drivers/usb/misc/Makefile | 1 +
drivers/usb/misc/usb5807.c | 184 +++++++++++++++++++++++++++++++++++++
3 files changed, 194 insertions(+)
create mode 100644 drivers/usb/misc/usb5807.c
diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
index 99b15b77dfd5..6659e917ea26 100644
--- a/drivers/usb/misc/Kconfig
+++ b/drivers/usb/misc/Kconfig
@@ -251,6 +251,15 @@ config USB_EZUSB_FX2
Say Y here if you need EZUSB device support.
(Cypress FX/FX2/FX2LP microcontrollers)
+config USB_HUB_USB5807
+ tristate "USB5807 Hub Controller Configuration Driver"
+ depends on I2C
+ help
+ This option enables support for configuration via SMBus of the
+ Microchip USB5807 USB 3.1 Hub Controller. Configuration parameters may
+ be set in devicetree.
+ Say Y or M here if you need to configure such a device via SMBus.
+
config USB_HUB_USB251XB
tristate "USB251XB Hub Controller Configuration Driver"
depends on I2C
diff --git a/drivers/usb/misc/Makefile b/drivers/usb/misc/Makefile
index 1992cc284d8a..e827ed251fa5 100644
--- a/drivers/usb/misc/Makefile
+++ b/drivers/usb/misc/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_USB_USS720) += uss720.o
obj-$(CONFIG_USB_SEVSEG) += usbsevseg.o
obj-$(CONFIG_USB_YUREX) += yurex.o
obj-$(CONFIG_USB_HUB_USB251XB) += usb251xb.o
+obj-$(CONFIG_USB_HUB_USB5807) += usb5807.o
obj-$(CONFIG_USB_HSIC_USB3503) += usb3503.o
obj-$(CONFIG_USB_HSIC_USB4604) += usb4604.o
obj-$(CONFIG_USB_CHAOSKEY) += chaoskey.o
diff --git a/drivers/usb/misc/usb5807.c b/drivers/usb/misc/usb5807.c
new file mode 100644
index 000000000000..c617f3371fa1
--- /dev/null
+++ b/drivers/usb/misc/usb5807.c
@@ -0,0 +1,184 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for Microchip USB5807 USB 3.1 Hub
+ * Configuration via SMBus.
+ *
+ * Copyright (c) 2023 Topic Embedded Products
+ */
+
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regulator/consumer.h>
+
+#define USB5807_CMD_ATTACH 0xAA55
+#define USB5807_CMD_CONFIG 0x9937
+
+#define USB5807_REG_LANE_SWAP 0x30FA
+
+#define USB5807_NUM_PORTS 7
+
+
+static int usb5807_write(struct i2c_client *i2c, void *buf, u8 len)
+{
+ int ret;
+ struct i2c_msg msg = {
+ .addr = i2c->addr,
+ .flags = 0x0,
+ .len = len,
+ .buf = buf,
+ };
+
+ ret = i2c_transfer(i2c->adapter, &msg, 1);
+ return ret < 0 ? ret : 0;
+}
+
+/*
+ * Send a command sequence, which is an I2C write transaction, with the command
+ * word in big endian and a terminating "0" byte.
+ */
+static int usb5807_command(struct i2c_client *i2c, u16 cmd)
+{
+ u8 buf[3] = {cmd >> 8, cmd & 0xff, 0};
+
+ return usb5807_write(i2c, buf, sizeof(buf));
+}
+
+static int usb5807_prepare_reg_u8(struct i2c_client *i2c, u16 reg, u8 value)
+{
+ u8 buf[] = {
+ 0x00,
+ 0x00, /* Memory offset */
+ 1 + 4, /* Transaction size */
+ 0x00, /* 0 = Register write operation */
+ 1, /* Size of register data */
+ (reg >> 8) & 0xff,
+ reg & 0xff, /* Register offset */
+ value, /* Register data */
+ 0 /* Terminating zero */
+ };
+
+ return usb5807_write(i2c, buf, sizeof(buf));
+}
+
+/*
+ * Write an 8-bit register. First we must write the "set register" operation to
+ * the chip's internal memory at offset 0, then issue a command to execute said
+ * operation.
+ */
+static int usb5807_write_reg_u8(struct i2c_client *i2c, u16 reg, u8 value)
+{
+ int ret;
+
+ ret = usb5807_prepare_reg_u8(i2c, reg, value);
+ if (ret)
+ return ret;
+
+ return usb5807_command(i2c, USB5807_CMD_CONFIG);
+}
+
+/* Decode array of port numbers property into bit mask */
+static u8 usb5807_get_ports_field(struct device *dev, const char *prop_name)
+{
+ struct property *prop;
+ const __be32 *p;
+ u32 port;
+ u8 result = 0;
+
+ of_property_for_each_u32(dev->of_node, prop_name, prop, p, port) {
+ if (port < USB5807_NUM_PORTS)
+ result |= BIT(port);
+ else
+ dev_warn(dev, "%s: port %u doesn't exist\n", prop_name,
+ port);
+ }
+ return result;
+}
+
+static int usb5807_i2c_probe(struct i2c_client *i2c)
+{
+ struct gpio_desc *reset_gpio;
+ int ret;
+ u8 val;
+
+ /* Reset the chip to bring it into configuration mode */
+ reset_gpio = devm_gpiod_get_optional(&i2c->dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(reset_gpio)) {
+ return dev_err_probe(&i2c->dev, PTR_ERR(reset_gpio),
+ "Failed to request reset GPIO\n");
+ }
+
+ /* Enable power supplies while chip is held in reset */
+ ret = devm_regulator_get_enable(&i2c->dev, "vdd12");
+ if (ret)
+ return ret;
+
+ ret = devm_regulator_get_enable(&i2c->dev, "vdd33");
+ if (ret)
+ return ret;
+
+ /* Reset timing: Assert for >= 5 us */
+ usleep_range(5, 10);
+
+ /* Lock the bus for >= 1ms while the hub reads the I2C strapping */
+ i2c_lock_bus(i2c->adapter, I2C_LOCK_SEGMENT);
+
+ gpiod_set_value_cansleep(reset_gpio, 0);
+ usleep_range(1000, 2000);
+
+ i2c_unlock_bus(i2c->adapter, I2C_LOCK_SEGMENT);
+
+ /* The hub device needs additional time to boot up */
+ msleep(20);
+
+ val = usb5807_get_ports_field(&i2c->dev, "swap-dx-lanes");
+ if (val) {
+ ret = usb5807_write_reg_u8(i2c, USB5807_REG_LANE_SWAP, val);
+ if (ret < 0)
+ dev_err(&i2c->dev, "Failed writing config: %d\n", ret);
+ }
+
+ /*
+ * Send the "Attach" command which makes the device disappear from the
+ * I2C bus and starts USB enumeration.
+ */
+ ret = usb5807_command(i2c, USB5807_CMD_ATTACH);
+ if (ret) {
+ dev_err(&i2c->dev, "Failed sending ATTACH command: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id usb5807_of_match[] = {
+ { .compatible = "microchip,usb5807" },
+ { } /* sentinel */
+};
+MODULE_DEVICE_TABLE(of, usb5807_of_match);
+
+static const struct i2c_device_id usb5807_id[] = {
+ { "usb5807", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, usb5807_id);
+
+static struct i2c_driver usb5807_i2c_driver = {
+ .driver = {
+ .name = "usb5807",
+ .of_match_table = of_match_ptr(usb5807_of_match),
+ },
+ .probe_new = usb5807_i2c_probe,
+ .id_table = usb5807_id,
+};
+
+module_i2c_driver(usb5807_i2c_driver);
+
+MODULE_AUTHOR("Mike Looijmans <mike.looijmans@xxxxxxxx>");
+MODULE_DESCRIPTION("USB5807 USB 3.1 Hub Controller Driver");
+MODULE_LICENSE("GPL");
--
2.17.1
Met vriendelijke groet / kind regards,
Mike Looijmans
System Expert
TOPIC Embedded Products B.V.
Materiaalweg 4, 5681 RJ Best
The Netherlands
T: +31 (0) 499 33 69 69
E: mike.looijmans@xxxxxxxxxxxxxxxxx
W: www.topic.nl
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