| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Driver for SMSC USB3503 USB 2.0 hub controller driver |
| * |
| * Copyright (c) 2012-2013 Dongjin Kim (tobetter@gmail.com) |
| */ |
| |
| #include <linux/clk.h> |
| #include <linux/i2c.h> |
| #include <linux/gpio.h> |
| #include <linux/delay.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/of_gpio.h> |
| #include <linux/platform_device.h> |
| #include <linux/platform_data/usb3503.h> |
| #include <linux/regmap.h> |
| |
| #define USB3503_VIDL 0x00 |
| #define USB3503_VIDM 0x01 |
| #define USB3503_PIDL 0x02 |
| #define USB3503_PIDM 0x03 |
| #define USB3503_DIDL 0x04 |
| #define USB3503_DIDM 0x05 |
| |
| #define USB3503_CFG1 0x06 |
| #define USB3503_SELF_BUS_PWR (1 << 7) |
| |
| #define USB3503_CFG2 0x07 |
| #define USB3503_CFG3 0x08 |
| #define USB3503_NRD 0x09 |
| |
| #define USB3503_PDS 0x0a |
| |
| #define USB3503_SP_ILOCK 0xe7 |
| #define USB3503_SPILOCK_CONNECT (1 << 1) |
| #define USB3503_SPILOCK_CONFIG (1 << 0) |
| |
| #define USB3503_CFGP 0xee |
| #define USB3503_CLKSUSP (1 << 7) |
| |
| #define USB3503_RESET 0xff |
| |
| struct usb3503 { |
| enum usb3503_mode mode; |
| struct regmap *regmap; |
| struct device *dev; |
| struct clk *clk; |
| u8 port_off_mask; |
| int gpio_intn; |
| int gpio_reset; |
| int gpio_connect; |
| bool secondary_ref_clk; |
| }; |
| |
| static int usb3503_reset(struct usb3503 *hub, int state) |
| { |
| if (!state && gpio_is_valid(hub->gpio_connect)) |
| gpio_set_value_cansleep(hub->gpio_connect, 0); |
| |
| if (gpio_is_valid(hub->gpio_reset)) |
| gpio_set_value_cansleep(hub->gpio_reset, state); |
| |
| /* Wait T_HUBINIT == 4ms for hub logic to stabilize */ |
| if (state) |
| usleep_range(4000, 10000); |
| |
| return 0; |
| } |
| |
| static int usb3503_connect(struct usb3503 *hub) |
| { |
| struct device *dev = hub->dev; |
| int err; |
| |
| usb3503_reset(hub, 1); |
| |
| if (hub->regmap) { |
| /* SP_ILOCK: set connect_n, config_n for config */ |
| err = regmap_write(hub->regmap, USB3503_SP_ILOCK, |
| (USB3503_SPILOCK_CONNECT |
| | USB3503_SPILOCK_CONFIG)); |
| if (err < 0) { |
| dev_err(dev, "SP_ILOCK failed (%d)\n", err); |
| return err; |
| } |
| |
| /* PDS : Set the ports which are disabled in self-powered mode. */ |
| if (hub->port_off_mask) { |
| err = regmap_update_bits(hub->regmap, USB3503_PDS, |
| hub->port_off_mask, |
| hub->port_off_mask); |
| if (err < 0) { |
| dev_err(dev, "PDS failed (%d)\n", err); |
| return err; |
| } |
| } |
| |
| /* CFG1 : Set SELF_BUS_PWR, this enables self-powered operation. */ |
| err = regmap_update_bits(hub->regmap, USB3503_CFG1, |
| USB3503_SELF_BUS_PWR, |
| USB3503_SELF_BUS_PWR); |
| if (err < 0) { |
| dev_err(dev, "CFG1 failed (%d)\n", err); |
| return err; |
| } |
| |
| /* SP_LOCK: clear connect_n, config_n for hub connect */ |
| err = regmap_update_bits(hub->regmap, USB3503_SP_ILOCK, |
| (USB3503_SPILOCK_CONNECT |
| | USB3503_SPILOCK_CONFIG), 0); |
| if (err < 0) { |
| dev_err(dev, "SP_ILOCK failed (%d)\n", err); |
| return err; |
| } |
| } |
| |
| if (gpio_is_valid(hub->gpio_connect)) |
| gpio_set_value_cansleep(hub->gpio_connect, 1); |
| |
| hub->mode = USB3503_MODE_HUB; |
| dev_info(dev, "switched to HUB mode\n"); |
| |
| return 0; |
| } |
| |
| static int usb3503_switch_mode(struct usb3503 *hub, enum usb3503_mode mode) |
| { |
| struct device *dev = hub->dev; |
| int err = 0; |
| |
| switch (mode) { |
| case USB3503_MODE_HUB: |
| err = usb3503_connect(hub); |
| break; |
| |
| case USB3503_MODE_STANDBY: |
| usb3503_reset(hub, 0); |
| dev_info(dev, "switched to STANDBY mode\n"); |
| break; |
| |
| default: |
| dev_err(dev, "unknown mode is requested\n"); |
| err = -EINVAL; |
| break; |
| } |
| |
| return err; |
| } |
| |
| static const struct regmap_config usb3503_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| |
| .max_register = USB3503_RESET, |
| }; |
| |
| static int usb3503_probe(struct usb3503 *hub) |
| { |
| struct device *dev = hub->dev; |
| struct usb3503_platform_data *pdata = dev_get_platdata(dev); |
| struct device_node *np = dev->of_node; |
| int err; |
| u32 mode = USB3503_MODE_HUB; |
| const u32 *property; |
| int len; |
| |
| if (pdata) { |
| hub->port_off_mask = pdata->port_off_mask; |
| hub->gpio_intn = pdata->gpio_intn; |
| hub->gpio_connect = pdata->gpio_connect; |
| hub->gpio_reset = pdata->gpio_reset; |
| hub->mode = pdata->initial_mode; |
| } else if (np) { |
| struct clk *clk; |
| u32 rate = 0; |
| hub->port_off_mask = 0; |
| |
| if (!of_property_read_u32(np, "refclk-frequency", &rate)) { |
| switch (rate) { |
| case 38400000: |
| case 26000000: |
| case 19200000: |
| case 12000000: |
| hub->secondary_ref_clk = 0; |
| break; |
| case 24000000: |
| case 27000000: |
| case 25000000: |
| case 50000000: |
| hub->secondary_ref_clk = 1; |
| break; |
| default: |
| dev_err(dev, |
| "unsupported reference clock rate (%d)\n", |
| (int) rate); |
| return -EINVAL; |
| } |
| } |
| |
| clk = devm_clk_get(dev, "refclk"); |
| if (IS_ERR(clk) && PTR_ERR(clk) != -ENOENT) { |
| dev_err(dev, "unable to request refclk (%ld)\n", |
| PTR_ERR(clk)); |
| return PTR_ERR(clk); |
| } |
| |
| if (!IS_ERR(clk)) { |
| hub->clk = clk; |
| |
| if (rate != 0) { |
| err = clk_set_rate(hub->clk, rate); |
| if (err) { |
| dev_err(dev, |
| "unable to set reference clock rate to %d\n", |
| (int) rate); |
| return err; |
| } |
| } |
| |
| err = clk_prepare_enable(hub->clk); |
| if (err) { |
| dev_err(dev, |
| "unable to enable reference clock\n"); |
| return err; |
| } |
| } |
| |
| property = of_get_property(np, "disabled-ports", &len); |
| if (property && (len / sizeof(u32)) > 0) { |
| int i; |
| for (i = 0; i < len / sizeof(u32); i++) { |
| u32 port = be32_to_cpu(property[i]); |
| if ((1 <= port) && (port <= 3)) |
| hub->port_off_mask |= (1 << port); |
| } |
| } |
| |
| hub->gpio_intn = of_get_named_gpio(np, "intn-gpios", 0); |
| if (hub->gpio_intn == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| hub->gpio_connect = of_get_named_gpio(np, "connect-gpios", 0); |
| if (hub->gpio_connect == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| hub->gpio_reset = of_get_named_gpio(np, "reset-gpios", 0); |
| if (hub->gpio_reset == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| of_property_read_u32(np, "initial-mode", &mode); |
| hub->mode = mode; |
| } |
| |
| if (hub->port_off_mask && !hub->regmap) |
| dev_err(dev, "Ports disabled with no control interface\n"); |
| |
| if (gpio_is_valid(hub->gpio_intn)) { |
| int val = hub->secondary_ref_clk ? GPIOF_OUT_INIT_LOW : |
| GPIOF_OUT_INIT_HIGH; |
| err = devm_gpio_request_one(dev, hub->gpio_intn, val, |
| "usb3503 intn"); |
| if (err) { |
| dev_err(dev, |
| "unable to request GPIO %d as interrupt pin (%d)\n", |
| hub->gpio_intn, err); |
| return err; |
| } |
| } |
| |
| if (gpio_is_valid(hub->gpio_connect)) { |
| err = devm_gpio_request_one(dev, hub->gpio_connect, |
| GPIOF_OUT_INIT_LOW, "usb3503 connect"); |
| if (err) { |
| dev_err(dev, |
| "unable to request GPIO %d as connect pin (%d)\n", |
| hub->gpio_connect, err); |
| return err; |
| } |
| } |
| |
| if (gpio_is_valid(hub->gpio_reset)) { |
| err = devm_gpio_request_one(dev, hub->gpio_reset, |
| GPIOF_OUT_INIT_LOW, "usb3503 reset"); |
| /* Datasheet defines a hardware reset to be at least 100us */ |
| usleep_range(100, 10000); |
| if (err) { |
| dev_err(dev, |
| "unable to request GPIO %d as reset pin (%d)\n", |
| hub->gpio_reset, err); |
| return err; |
| } |
| } |
| |
| usb3503_switch_mode(hub, hub->mode); |
| |
| dev_info(dev, "%s: probed in %s mode\n", __func__, |
| (hub->mode == USB3503_MODE_HUB) ? "hub" : "standby"); |
| |
| return 0; |
| } |
| |
| static int usb3503_i2c_probe(struct i2c_client *i2c, |
| const struct i2c_device_id *id) |
| { |
| struct usb3503 *hub; |
| int err; |
| |
| hub = devm_kzalloc(&i2c->dev, sizeof(struct usb3503), GFP_KERNEL); |
| if (!hub) |
| return -ENOMEM; |
| |
| i2c_set_clientdata(i2c, hub); |
| hub->regmap = devm_regmap_init_i2c(i2c, &usb3503_regmap_config); |
| if (IS_ERR(hub->regmap)) { |
| err = PTR_ERR(hub->regmap); |
| dev_err(&i2c->dev, "Failed to initialise regmap: %d\n", err); |
| return err; |
| } |
| hub->dev = &i2c->dev; |
| |
| return usb3503_probe(hub); |
| } |
| |
| static int usb3503_i2c_remove(struct i2c_client *i2c) |
| { |
| struct usb3503 *hub; |
| |
| hub = i2c_get_clientdata(i2c); |
| if (hub->clk) |
| clk_disable_unprepare(hub->clk); |
| |
| return 0; |
| } |
| |
| static int usb3503_platform_probe(struct platform_device *pdev) |
| { |
| struct usb3503 *hub; |
| |
| hub = devm_kzalloc(&pdev->dev, sizeof(struct usb3503), GFP_KERNEL); |
| if (!hub) |
| return -ENOMEM; |
| hub->dev = &pdev->dev; |
| platform_set_drvdata(pdev, hub); |
| |
| return usb3503_probe(hub); |
| } |
| |
| static int usb3503_platform_remove(struct platform_device *pdev) |
| { |
| struct usb3503 *hub; |
| |
| hub = platform_get_drvdata(pdev); |
| if (hub->clk) |
| clk_disable_unprepare(hub->clk); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int usb3503_i2c_suspend(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct usb3503 *hub = i2c_get_clientdata(client); |
| |
| usb3503_switch_mode(hub, USB3503_MODE_STANDBY); |
| |
| if (hub->clk) |
| clk_disable_unprepare(hub->clk); |
| |
| return 0; |
| } |
| |
| static int usb3503_i2c_resume(struct device *dev) |
| { |
| struct i2c_client *client = to_i2c_client(dev); |
| struct usb3503 *hub = i2c_get_clientdata(client); |
| |
| if (hub->clk) |
| clk_prepare_enable(hub->clk); |
| |
| usb3503_switch_mode(hub, hub->mode); |
| |
| return 0; |
| } |
| #endif |
| |
| static SIMPLE_DEV_PM_OPS(usb3503_i2c_pm_ops, usb3503_i2c_suspend, |
| usb3503_i2c_resume); |
| |
| static const struct i2c_device_id usb3503_id[] = { |
| { USB3503_I2C_NAME, 0 }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, usb3503_id); |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id usb3503_of_match[] = { |
| { .compatible = "smsc,usb3503", }, |
| { .compatible = "smsc,usb3503a", }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, usb3503_of_match); |
| #endif |
| |
| static struct i2c_driver usb3503_i2c_driver = { |
| .driver = { |
| .name = USB3503_I2C_NAME, |
| .pm = &usb3503_i2c_pm_ops, |
| .of_match_table = of_match_ptr(usb3503_of_match), |
| }, |
| .probe = usb3503_i2c_probe, |
| .remove = usb3503_i2c_remove, |
| .id_table = usb3503_id, |
| }; |
| |
| static struct platform_driver usb3503_platform_driver = { |
| .driver = { |
| .name = USB3503_I2C_NAME, |
| .of_match_table = of_match_ptr(usb3503_of_match), |
| }, |
| .probe = usb3503_platform_probe, |
| .remove = usb3503_platform_remove, |
| }; |
| |
| static int __init usb3503_init(void) |
| { |
| int err; |
| |
| err = i2c_add_driver(&usb3503_i2c_driver); |
| if (err != 0) |
| pr_err("usb3503: Failed to register I2C driver: %d\n", err); |
| |
| err = platform_driver_register(&usb3503_platform_driver); |
| if (err != 0) |
| pr_err("usb3503: Failed to register platform driver: %d\n", |
| err); |
| |
| return 0; |
| } |
| module_init(usb3503_init); |
| |
| static void __exit usb3503_exit(void) |
| { |
| platform_driver_unregister(&usb3503_platform_driver); |
| i2c_del_driver(&usb3503_i2c_driver); |
| } |
| module_exit(usb3503_exit); |
| |
| MODULE_AUTHOR("Dongjin Kim <tobetter@gmail.com>"); |
| MODULE_DESCRIPTION("USB3503 USB HUB driver"); |
| MODULE_LICENSE("GPL"); |