// SPDX-License-Identifier: GPL-2.0+ /* * Driver for Microchip USB251xB USB 2.0 Hi-Speed Hub Controller * Configuration via SMBus. * * Copyright (c) 2017 SKIDATA AG * * This work is based on the USB3503 driver by Dongjin Kim and * a not-accepted patch by Fabien Lahoudere, see: * https://patchwork.kernel.org/patch/9257715/ */ #include #include #include #include #include #include #include #include #include /* Internal Register Set Addresses & Default Values acc. to DS00001692C */ #define USB251XB_ADDR_VENDOR_ID_LSB 0x00 #define USB251XB_ADDR_VENDOR_ID_MSB 0x01 #define USB251XB_DEF_VENDOR_ID 0x0424 #define USB251XB_ADDR_PRODUCT_ID_LSB 0x02 #define USB251XB_ADDR_PRODUCT_ID_MSB 0x03 #define USB251XB_ADDR_DEVICE_ID_LSB 0x04 #define USB251XB_ADDR_DEVICE_ID_MSB 0x05 #define USB251XB_DEF_DEVICE_ID 0x0BB3 #define USB251XB_ADDR_CONFIG_DATA_1 0x06 #define USB251XB_DEF_CONFIG_DATA_1 0x9B #define USB251XB_ADDR_CONFIG_DATA_2 0x07 #define USB251XB_DEF_CONFIG_DATA_2 0x20 #define USB251XB_ADDR_CONFIG_DATA_3 0x08 #define USB251XB_DEF_CONFIG_DATA_3 0x02 #define USB251XB_ADDR_NON_REMOVABLE_DEVICES 0x09 #define USB251XB_DEF_NON_REMOVABLE_DEVICES 0x00 #define USB251XB_ADDR_PORT_DISABLE_SELF 0x0A #define USB251XB_DEF_PORT_DISABLE_SELF 0x00 #define USB251XB_ADDR_PORT_DISABLE_BUS 0x0B #define USB251XB_DEF_PORT_DISABLE_BUS 0x00 #define USB251XB_ADDR_MAX_POWER_SELF 0x0C #define USB251XB_DEF_MAX_POWER_SELF 0x01 #define USB251XB_ADDR_MAX_POWER_BUS 0x0D #define USB251XB_DEF_MAX_POWER_BUS 0x32 #define USB251XB_ADDR_MAX_CURRENT_SELF 0x0E #define USB251XB_DEF_MAX_CURRENT_SELF 0x01 #define USB251XB_ADDR_MAX_CURRENT_BUS 0x0F #define USB251XB_DEF_MAX_CURRENT_BUS 0x32 #define USB251XB_ADDR_POWER_ON_TIME 0x10 #define USB251XB_DEF_POWER_ON_TIME 0x32 #define USB251XB_ADDR_LANGUAGE_ID_HIGH 0x11 #define USB251XB_ADDR_LANGUAGE_ID_LOW 0x12 #define USB251XB_DEF_LANGUAGE_ID 0x0000 #define USB251XB_STRING_BUFSIZE 62 #define USB251XB_ADDR_MANUFACTURER_STRING_LEN 0x13 #define USB251XB_ADDR_MANUFACTURER_STRING 0x16 #define USB251XB_DEF_MANUFACTURER_STRING "Microchip" #define USB251XB_ADDR_PRODUCT_STRING_LEN 0x14 #define USB251XB_ADDR_PRODUCT_STRING 0x54 #define USB251XB_ADDR_SERIAL_STRING_LEN 0x15 #define USB251XB_ADDR_SERIAL_STRING 0x92 #define USB251XB_DEF_SERIAL_STRING "" #define USB251XB_ADDR_BATTERY_CHARGING_ENABLE 0xD0 #define USB251XB_DEF_BATTERY_CHARGING_ENABLE 0x00 #define USB251XB_ADDR_BOOST_UP 0xF6 #define USB251XB_DEF_BOOST_UP 0x00 #define USB251XB_ADDR_BOOST_57 0xF7 #define USB251XB_DEF_BOOST_57 0x00 #define USB251XB_ADDR_BOOST_14 0xF8 #define USB251XB_DEF_BOOST_14 0x00 #define USB251XB_ADDR_PORT_SWAP 0xFA #define USB251XB_DEF_PORT_SWAP 0x00 #define USB251XB_ADDR_PORT_MAP_12 0xFB #define USB251XB_DEF_PORT_MAP_12 0x00 #define USB251XB_ADDR_PORT_MAP_34 0xFC #define USB251XB_DEF_PORT_MAP_34 0x00 /* USB251{3B/i,4B/i,7/i} only */ #define USB251XB_ADDR_PORT_MAP_56 0xFD #define USB251XB_DEF_PORT_MAP_56 0x00 /* USB2517/i only */ #define USB251XB_ADDR_PORT_MAP_7 0xFE #define USB251XB_DEF_PORT_MAP_7 0x00 /* USB2517/i only */ #define USB251XB_ADDR_STATUS_COMMAND 0xFF #define USB251XB_STATUS_COMMAND_SMBUS_DOWN 0x04 #define USB251XB_STATUS_COMMAND_RESET 0x02 #define USB251XB_STATUS_COMMAND_ATTACH 0x01 #define USB251XB_I2C_REG_SZ 0x100 #define USB251XB_I2C_WRITE_SZ 0x10 #define DRIVER_NAME "usb251xb" #define DRIVER_DESC "Microchip USB 2.0 Hi-Speed Hub Controller" struct usb251xb { struct device *dev; struct i2c_client *i2c; struct regulator *vdd; u8 skip_config; struct gpio_desc *gpio_reset; u16 vendor_id; u16 product_id; u16 device_id; u8 conf_data1; u8 conf_data2; u8 conf_data3; u8 non_rem_dev; u8 port_disable_sp; u8 port_disable_bp; u8 max_power_sp; u8 max_power_bp; u8 max_current_sp; u8 max_current_bp; u8 power_on_time; u16 lang_id; u8 manufacturer_len; u8 product_len; u8 serial_len; char manufacturer[USB251XB_STRING_BUFSIZE]; char product[USB251XB_STRING_BUFSIZE]; char serial[USB251XB_STRING_BUFSIZE]; u8 bat_charge_en; u8 boost_up; u8 boost_57; u8 boost_14; u8 port_swap; u8 port_map12; u8 port_map34; u8 port_map56; u8 port_map7; u8 status; }; struct usb251xb_data { u16 product_id; u8 port_cnt; bool led_support; bool bat_support; char product_str[USB251XB_STRING_BUFSIZE / 2]; /* ASCII string */ }; static const struct usb251xb_data usb2422_data = { .product_id = 0x2422, .port_cnt = 2, .led_support = false, .bat_support = true, .product_str = "USB2422", }; static const struct usb251xb_data usb2512b_data = { .product_id = 0x2512, .port_cnt = 2, .led_support = false, .bat_support = true, .product_str = "USB2512B", }; static const struct usb251xb_data usb2512bi_data = { .product_id = 0x2512, .port_cnt = 2, .led_support = false, .bat_support = true, .product_str = "USB2512Bi", }; static const struct usb251xb_data usb2513b_data = { .product_id = 0x2513, .port_cnt = 3, .led_support = false, .bat_support = true, .product_str = "USB2513B", }; static const struct usb251xb_data usb2513bi_data = { .product_id = 0x2513, .port_cnt = 3, .led_support = false, .bat_support = true, .product_str = "USB2513Bi", }; static const struct usb251xb_data usb2514b_data = { .product_id = 0x2514, .port_cnt = 4, .led_support = false, .bat_support = true, .product_str = "USB2514B", }; static const struct usb251xb_data usb2514bi_data = { .product_id = 0x2514, .port_cnt = 4, .led_support = false, .bat_support = true, .product_str = "USB2514Bi", }; static const struct usb251xb_data usb2517_data = { .product_id = 0x2517, .port_cnt = 7, .led_support = true, .bat_support = false, .product_str = "USB2517", }; static const struct usb251xb_data usb2517i_data = { .product_id = 0x2517, .port_cnt = 7, .led_support = true, .bat_support = false, .product_str = "USB2517i", }; #ifdef CONFIG_GPIOLIB static int usb251xb_check_dev_children(struct device *dev, void *child) { if (dev->type == &i2c_adapter_type) { return device_for_each_child(dev, child, usb251xb_check_dev_children); } return (dev == child); } static int usb251x_check_gpio_chip(struct usb251xb *hub) { struct gpio_chip *gc = gpiod_to_chip(hub->gpio_reset); struct i2c_adapter *adap = hub->i2c->adapter; int ret; if (!hub->gpio_reset) return 0; if (!gc) return -EINVAL; ret = usb251xb_check_dev_children(&adap->dev, gc->parent); if (ret) { dev_err(hub->dev, "Reset GPIO chip is at the same i2c-bus\n"); return -EINVAL; } return 0; } #else static int usb251x_check_gpio_chip(struct usb251xb *hub) { return 0; } #endif static void usb251xb_reset(struct usb251xb *hub) { if (!hub->gpio_reset) return; i2c_lock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT); gpiod_set_value_cansleep(hub->gpio_reset, 1); usleep_range(1, 10); /* >=1us RESET_N asserted */ gpiod_set_value_cansleep(hub->gpio_reset, 0); /* wait for hub recovery/stabilization */ usleep_range(500, 750); /* >=500us after RESET_N deasserted */ i2c_unlock_bus(hub->i2c->adapter, I2C_LOCK_SEGMENT); } static int usb251xb_connect(struct usb251xb *hub) { struct device *dev = hub->dev; int err, i; char i2c_wb[USB251XB_I2C_REG_SZ]; memset(i2c_wb, 0, USB251XB_I2C_REG_SZ); if (hub->skip_config) { dev_info(dev, "Skip hub configuration, only attach.\n"); i2c_wb[0] = 0x01; i2c_wb[1] = USB251XB_STATUS_COMMAND_ATTACH; usb251xb_reset(hub); err = i2c_smbus_write_i2c_block_data(hub->i2c, USB251XB_ADDR_STATUS_COMMAND, 2, i2c_wb); if (err) { dev_err(dev, "attaching hub failed: %d\n", err); return err; } return 0; } i2c_wb[USB251XB_ADDR_VENDOR_ID_MSB] = (hub->vendor_id >> 8) & 0xFF; i2c_wb[USB251XB_ADDR_VENDOR_ID_LSB] = hub->vendor_id & 0xFF; i2c_wb[USB251XB_ADDR_PRODUCT_ID_MSB] = (hub->product_id >> 8) & 0xFF; i2c_wb[USB251XB_ADDR_PRODUCT_ID_LSB] = hub->product_id & 0xFF; i2c_wb[USB251XB_ADDR_DEVICE_ID_MSB] = (hub->device_id >> 8) & 0xFF; i2c_wb[USB251XB_ADDR_DEVICE_ID_LSB] = hub->device_id & 0xFF; i2c_wb[USB251XB_ADDR_CONFIG_DATA_1] = hub->conf_data1; i2c_wb[USB251XB_ADDR_CONFIG_DATA_2] = hub->conf_data2; i2c_wb[USB251XB_ADDR_CONFIG_DATA_3] = hub->conf_data3; i2c_wb[USB251XB_ADDR_NON_REMOVABLE_DEVICES] = hub->non_rem_dev; i2c_wb[USB251XB_ADDR_PORT_DISABLE_SELF] = hub->port_disable_sp; i2c_wb[USB251XB_ADDR_PORT_DISABLE_BUS] = hub->port_disable_bp; i2c_wb[USB251XB_ADDR_MAX_POWER_SELF] = hub->max_power_sp; i2c_wb[USB251XB_ADDR_MAX_POWER_BUS] = hub->max_power_bp; i2c_wb[USB251XB_ADDR_MAX_CURRENT_SELF] = hub->max_current_sp; i2c_wb[USB251XB_ADDR_MAX_CURRENT_BUS] = hub->max_current_bp; i2c_wb[USB251XB_ADDR_POWER_ON_TIME] = hub->power_on_time; i2c_wb[USB251XB_ADDR_LANGUAGE_ID_HIGH] = (hub->lang_id >> 8) & 0xFF; i2c_wb[USB251XB_ADDR_LANGUAGE_ID_LOW] = hub->lang_id & 0xFF; i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING_LEN] = hub->manufacturer_len; i2c_wb[USB251XB_ADDR_PRODUCT_STRING_LEN] = hub->product_len; i2c_wb[USB251XB_ADDR_SERIAL_STRING_LEN] = hub->serial_len; memcpy(&i2c_wb[USB251XB_ADDR_MANUFACTURER_STRING], hub->manufacturer, USB251XB_STRING_BUFSIZE); memcpy(&i2c_wb[USB251XB_ADDR_SERIAL_STRING], hub->serial, USB251XB_STRING_BUFSIZE); memcpy(&i2c_wb[USB251XB_ADDR_PRODUCT_STRING], hub->product, USB251XB_STRING_BUFSIZE); i2c_wb[USB251XB_ADDR_BATTERY_CHARGING_ENABLE] = hub->bat_charge_en; i2c_wb[USB251XB_ADDR_BOOST_UP] = hub->boost_up; i2c_wb[USB251XB_ADDR_BOOST_57] = hub->boost_57; i2c_wb[USB251XB_ADDR_BOOST_14] = hub->boost_14; i2c_wb[USB251XB_ADDR_PORT_SWAP] = hub->port_swap; i2c_wb[USB251XB_ADDR_PORT_MAP_12] = hub->port_map12; i2c_wb[USB251XB_ADDR_PORT_MAP_34] = hub->port_map34; i2c_wb[USB251XB_ADDR_PORT_MAP_56] = hub->port_map56; i2c_wb[USB251XB_ADDR_PORT_MAP_7] = hub->port_map7; i2c_wb[USB251XB_ADDR_STATUS_COMMAND] = USB251XB_STATUS_COMMAND_ATTACH; usb251xb_reset(hub); /* write registers */ for (i = 0; i < (USB251XB_I2C_REG_SZ / USB251XB_I2C_WRITE_SZ); i++) { int offset = i * USB251XB_I2C_WRITE_SZ; char wbuf[USB251XB_I2C_WRITE_SZ + 1]; /* The first data byte transferred tells the hub how many data * bytes will follow (byte count). */ wbuf[0] = USB251XB_I2C_WRITE_SZ; memcpy(&wbuf[1], &i2c_wb[offset], USB251XB_I2C_WRITE_SZ); dev_dbg(dev, "writing %d byte block %d to 0x%02X\n", USB251XB_I2C_WRITE_SZ, i, offset); err = i2c_smbus_write_i2c_block_data(hub->i2c, offset, USB251XB_I2C_WRITE_SZ + 1, wbuf); if (err) goto out_err; } dev_info(dev, "Hub configuration was successful.\n"); return 0; out_err: dev_err(dev, "configuring block %d failed: %d\n", i, err); return err; } static void usb251xb_get_ports_field(struct usb251xb *hub, const char *prop_name, u8 port_cnt, bool ds_only, u8 *fld) { struct device *dev = hub->dev; struct property *prop; const __be32 *p; u32 port; of_property_for_each_u32(dev->of_node, prop_name, prop, p, port) { if ((port >= ds_only ? 1 : 0) && (port <= port_cnt)) *fld |= BIT(port); else dev_warn(dev, "port %u doesn't exist\n", port); } } static int usb251xb_get_ofdata(struct usb251xb *hub, const struct usb251xb_data *data) { struct device *dev = hub->dev; struct device_node *np = dev->of_node; int len; u32 property_u32 = 0; const char *cproperty_char; char str[USB251XB_STRING_BUFSIZE / 2]; if (!np) { dev_err(dev, "failed to get ofdata\n"); return -ENODEV; } hub->skip_config = of_property_read_bool(np, "skip-config"); hub->gpio_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(hub->gpio_reset)) return dev_err_probe(dev, PTR_ERR(hub->gpio_reset), "unable to request GPIO reset pin\n"); if (of_property_read_u16(np, "vendor-id", &hub->vendor_id)) hub->vendor_id = USB251XB_DEF_VENDOR_ID; if (of_property_read_u16(np, "product-id", &hub->product_id)) hub->product_id = data->product_id; if (of_property_read_u16(np, "device-id", &hub->device_id)) hub->device_id = USB251XB_DEF_DEVICE_ID; hub->conf_data1 = USB251XB_DEF_CONFIG_DATA_1; if (of_property_read_bool(np, "self-powered")) { hub->conf_data1 |= BIT(7); /* Configure Over-Current sens when self-powered */ hub->conf_data1 &= ~BIT(2); if (of_property_read_bool(np, "ganged-sensing")) hub->conf_data1 &= ~BIT(1); else if (of_property_read_bool(np, "individual-sensing")) hub->conf_data1 |= BIT(1); } else if (of_property_read_bool(np, "bus-powered")) { hub->conf_data1 &= ~BIT(7); /* Disable Over-Current sense when bus-powered */ hub->conf_data1 |= BIT(2); } if (of_property_read_bool(np, "disable-hi-speed")) hub->conf_data1 |= BIT(5); if (of_property_read_bool(np, "multi-tt")) hub->conf_data1 |= BIT(4); else if (of_property_read_bool(np, "single-tt")) hub->conf_data1 &= ~BIT(4); if (of_property_read_bool(np, "disable-eop")) hub->conf_data1 |= BIT(3); if (of_property_read_bool(np, "individual-port-switching")) hub->conf_data1 |= BIT(0); else if (of_property_read_bool(np, "ganged-port-switching")) hub->conf_data1 &= ~BIT(0); hub->conf_data2 = USB251XB_DEF_CONFIG_DATA_2; if (of_property_read_bool(np, "dynamic-power-switching")) hub->conf_data2 |= BIT(7); if (!of_property_read_u32(np, "oc-delay-us", &property_u32)) { if (property_u32 == 100) { /* 100 us*/ hub->conf_data2 &= ~BIT(5); hub->conf_data2 &= ~BIT(4); } else if (property_u32 == 4000) { /* 4 ms */ hub->conf_data2 &= ~BIT(5); hub->conf_data2 |= BIT(4); } else if (property_u32 == 16000) { /* 16 ms */ hub->conf_data2 |= BIT(5); hub->conf_data2 |= BIT(4); } else { /* 8 ms (DEFAULT) */ hub->conf_data2 |= BIT(5); hub->conf_data2 &= ~BIT(4); } } if (of_property_read_bool(np, "compound-device")) hub->conf_data2 |= BIT(3); hub->conf_data3 = USB251XB_DEF_CONFIG_DATA_3; if (of_property_read_bool(np, "port-mapping-mode")) hub->conf_data3 |= BIT(3); if (data->led_support && of_get_property(np, "led-usb-mode", NULL)) hub->conf_data3 &= ~BIT(1); if (of_property_read_bool(np, "string-support")) hub->conf_data3 |= BIT(0); hub->non_rem_dev = USB251XB_DEF_NON_REMOVABLE_DEVICES; usb251xb_get_ports_field(hub, "non-removable-ports", data->port_cnt, true, &hub->non_rem_dev); hub->port_disable_sp = USB251XB_DEF_PORT_DISABLE_SELF; usb251xb_get_ports_field(hub, "sp-disabled-ports", data->port_cnt, true, &hub->port_disable_sp); hub->port_disable_bp = USB251XB_DEF_PORT_DISABLE_BUS; usb251xb_get_ports_field(hub, "bp-disabled-ports", data->port_cnt, true, &hub->port_disable_bp); hub->max_power_sp = USB251XB_DEF_MAX_POWER_SELF; if (!of_property_read_u32(np, "sp-max-total-current-microamp", &property_u32)) hub->max_power_sp = min_t(u8, property_u32 / 2000, 50); hub->max_power_bp = USB251XB_DEF_MAX_POWER_BUS; if (!of_property_read_u32(np, "bp-max-total-current-microamp", &property_u32)) hub->max_power_bp = min_t(u8, property_u32 / 2000, 255); hub->max_current_sp = USB251XB_DEF_MAX_CURRENT_SELF; if (!of_property_read_u32(np, "sp-max-removable-current-microamp", &property_u32)) hub->max_current_sp = min_t(u8, property_u32 / 2000, 50); hub->max_current_bp = USB251XB_DEF_MAX_CURRENT_BUS; if (!of_property_read_u32(np, "bp-max-removable-current-microamp", &property_u32)) hub->max_current_bp = min_t(u8, property_u32 / 2000, 255); hub->power_on_time = USB251XB_DEF_POWER_ON_TIME; if (!of_property_read_u32(np, "power-on-time-ms", &property_u32)) hub->power_on_time = min_t(u8, property_u32 / 2, 255); if (of_property_read_u16(np, "language-id", &hub->lang_id)) hub->lang_id = USB251XB_DEF_LANGUAGE_ID; if (of_property_read_u8(np, "boost-up", &hub->boost_up)) hub->boost_up = USB251XB_DEF_BOOST_UP; cproperty_char = of_get_property(np, "manufacturer", NULL); strscpy(str, cproperty_char ? : USB251XB_DEF_MANUFACTURER_STRING, sizeof(str)); hub->manufacturer_len = strlen(str) & 0xFF; memset(hub->manufacturer, 0, USB251XB_STRING_BUFSIZE); len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str)); len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN, (wchar_t *)hub->manufacturer, USB251XB_STRING_BUFSIZE); cproperty_char = of_get_property(np, "product", NULL); strscpy(str, cproperty_char ? : data->product_str, sizeof(str)); hub->product_len = strlen(str) & 0xFF; memset(hub->product, 0, USB251XB_STRING_BUFSIZE); len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str)); len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN, (wchar_t *)hub->product, USB251XB_STRING_BUFSIZE); cproperty_char = of_get_property(np, "serial", NULL); strscpy(str, cproperty_char ? : USB251XB_DEF_SERIAL_STRING, sizeof(str)); hub->serial_len = strlen(str) & 0xFF; memset(hub->serial, 0, USB251XB_STRING_BUFSIZE); len = min_t(size_t, USB251XB_STRING_BUFSIZE / 2, strlen(str)); len = utf8s_to_utf16s(str, len, UTF16_LITTLE_ENDIAN, (wchar_t *)hub->serial, USB251XB_STRING_BUFSIZE); /* * The datasheet documents the register as 'Port Swap' but in real the * register controls the USB DP/DM signal swapping for each port. */ hub->port_swap = USB251XB_DEF_PORT_SWAP; usb251xb_get_ports_field(hub, "swap-dx-lanes", data->port_cnt, false, &hub->port_swap); /* The following parameters are currently not exposed to devicetree, but * may be as soon as needed. */ hub->bat_charge_en = USB251XB_DEF_BATTERY_CHARGING_ENABLE; hub->boost_57 = USB251XB_DEF_BOOST_57; hub->boost_14 = USB251XB_DEF_BOOST_14; hub->port_map12 = USB251XB_DEF_PORT_MAP_12; hub->port_map34 = USB251XB_DEF_PORT_MAP_34; hub->port_map56 = USB251XB_DEF_PORT_MAP_56; hub->port_map7 = USB251XB_DEF_PORT_MAP_7; return 0; } static const struct of_device_id usb251xb_of_match[] = { { .compatible = "microchip,usb2422", .data = &usb2422_data, }, { .compatible = "microchip,usb2512b", .data = &usb2512b_data, }, { .compatible = "microchip,usb2512bi", .data = &usb2512bi_data, }, { .compatible = "microchip,usb2513b", .data = &usb2513b_data, }, { .compatible = "microchip,usb2513bi", .data = &usb2513bi_data, }, { .compatible = "microchip,usb2514b", .data = &usb2514b_data, }, { .compatible = "microchip,usb2514bi", .data = &usb2514bi_data, }, { .compatible = "microchip,usb2517", .data = &usb2517_data, }, { .compatible = "microchip,usb2517i", .data = &usb2517i_data, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, usb251xb_of_match); static void usb251xb_regulator_disable_action(void *data) { struct usb251xb *hub = data; regulator_disable(hub->vdd); } static int usb251xb_probe(struct usb251xb *hub) { struct device *dev = hub->dev; struct device_node *np = dev->of_node; const struct usb251xb_data *usb_data = of_device_get_match_data(dev); int err; if (np && usb_data) { err = usb251xb_get_ofdata(hub, usb_data); if (err) { dev_err(dev, "failed to get ofdata: %d\n", err); return err; } } /* * usb251x SMBus-slave SCL lane is muxed with CFG_SEL0 pin. So if anyone * tries to work with the bus at the moment the hub reset is released, * it may cause an invalid config being latched by usb251x. Particularly * one of the config modes makes the hub loading a default registers * value without SMBus-slave interface activation. If the hub * accidentally gets this mode, this will cause the driver SMBus- * functions failure. Normally we could just lock the SMBus-segment the * hub i2c-interface resides for the device-specific reset timing. But * the GPIO controller, which is used to handle the hub reset, might be * placed at the same i2c-bus segment. In this case an error should be * returned since we can't safely use the GPIO controller to clear the * reset state (it may affect the hub configuration) and we can't lock * the i2c-bus segment (it will cause a deadlock). */ err = usb251x_check_gpio_chip(hub); if (err) return err; hub->vdd = devm_regulator_get(dev, "vdd"); if (IS_ERR(hub->vdd)) return PTR_ERR(hub->vdd); err = regulator_enable(hub->vdd); if (err) return err; err = devm_add_action_or_reset(dev, usb251xb_regulator_disable_action, hub); if (err) return err; err = usb251xb_connect(hub); if (err) { dev_err(dev, "Failed to connect hub (%d)\n", err); return err; } dev_info(dev, "Hub probed successfully\n"); return 0; } static int usb251xb_i2c_probe(struct i2c_client *i2c) { struct usb251xb *hub; hub = devm_kzalloc(&i2c->dev, sizeof(struct usb251xb), GFP_KERNEL); if (!hub) return -ENOMEM; i2c_set_clientdata(i2c, hub); hub->dev = &i2c->dev; hub->i2c = i2c; return usb251xb_probe(hub); } static int __maybe_unused usb251xb_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct usb251xb *hub = i2c_get_clientdata(client); return regulator_disable(hub->vdd); } static int __maybe_unused usb251xb_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct usb251xb *hub = i2c_get_clientdata(client); int err; err = regulator_enable(hub->vdd); if (err) return err; return usb251xb_connect(hub); } static SIMPLE_DEV_PM_OPS(usb251xb_pm_ops, usb251xb_suspend, usb251xb_resume); static const struct i2c_device_id usb251xb_id[] = { { "usb2422" }, { "usb2512b" }, { "usb2512bi" }, { "usb2513b" }, { "usb2513bi" }, { "usb2514b" }, { "usb2514bi" }, { "usb2517" }, { "usb2517i" }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(i2c, usb251xb_id); static struct i2c_driver usb251xb_i2c_driver = { .driver = { .name = DRIVER_NAME, .of_match_table = usb251xb_of_match, .pm = &usb251xb_pm_ops, }, .probe = usb251xb_i2c_probe, .id_table = usb251xb_id, }; module_i2c_driver(usb251xb_i2c_driver); MODULE_AUTHOR("Richard Leitner "); MODULE_DESCRIPTION("USB251x/xBi USB 2.0 Hub Controller Driver"); MODULE_LICENSE("GPL");