diff options
Diffstat (limited to 'drivers/usb/gadget/legacy/serial.c')
-rw-r--r-- | drivers/usb/gadget/legacy/serial.c | 324 |
1 files changed, 324 insertions, 0 deletions
diff --git a/drivers/usb/gadget/legacy/serial.c b/drivers/usb/gadget/legacy/serial.c new file mode 100644 index 000000000..dcd3a6603 --- /dev/null +++ b/drivers/usb/gadget/legacy/serial.c @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * serial.c -- USB gadget serial driver + * + * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com) + * Copyright (C) 2008 by David Brownell + * Copyright (C) 2008 by Nokia Corporation + */ + +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> + +#include "u_serial.h" + + +/* Defines */ + +#define GS_VERSION_STR "v2.4" +#define GS_VERSION_NUM 0x2400 + +#define GS_LONG_NAME "Gadget Serial" +#define GS_VERSION_NAME GS_LONG_NAME " " GS_VERSION_STR + +/*-------------------------------------------------------------------------*/ +USB_GADGET_COMPOSITE_OPTIONS(); + +/* Thanks to NetChip Technologies for donating this product ID. +* +* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!! +* Instead: allocate your own, using normal USB-IF procedures. +*/ +#define GS_VENDOR_ID 0x0525 /* NetChip */ +#define GS_PRODUCT_ID 0xa4a6 /* Linux-USB Serial Gadget */ +#define GS_CDC_PRODUCT_ID 0xa4a7 /* ... as CDC-ACM */ +#define GS_CDC_OBEX_PRODUCT_ID 0xa4a9 /* ... as CDC-OBEX */ + +/* string IDs are assigned dynamically */ + +#define STRING_DESCRIPTION_IDX USB_GADGET_FIRST_AVAIL_IDX + +static struct usb_string strings_dev[] = { + [USB_GADGET_MANUFACTURER_IDX].s = "", + [USB_GADGET_PRODUCT_IDX].s = GS_VERSION_NAME, + [USB_GADGET_SERIAL_IDX].s = "", + [STRING_DESCRIPTION_IDX].s = NULL /* updated; f(use_acm) */, + { } /* end of list */ +}; + +static struct usb_gadget_strings stringtab_dev = { + .language = 0x0409, /* en-us */ + .strings = strings_dev, +}; + +static struct usb_gadget_strings *dev_strings[] = { + &stringtab_dev, + NULL, +}; + +static struct usb_device_descriptor device_desc = { + .bLength = USB_DT_DEVICE_SIZE, + .bDescriptorType = USB_DT_DEVICE, + /* .bcdUSB = DYNAMIC */ + /* .bDeviceClass = f(use_acm) */ + .bDeviceSubClass = 0, + .bDeviceProtocol = 0, + /* .bMaxPacketSize0 = f(hardware) */ + .idVendor = cpu_to_le16(GS_VENDOR_ID), + /* .idProduct = f(use_acm) */ + .bcdDevice = cpu_to_le16(GS_VERSION_NUM), + /* .iManufacturer = DYNAMIC */ + /* .iProduct = DYNAMIC */ + .bNumConfigurations = 1, +}; + +static const struct usb_descriptor_header *otg_desc[2]; + +/*-------------------------------------------------------------------------*/ + +/* Module */ +MODULE_DESCRIPTION(GS_VERSION_NAME); +MODULE_AUTHOR("Al Borchers"); +MODULE_AUTHOR("David Brownell"); +MODULE_LICENSE("GPL"); + +static bool use_acm = true; +module_param(use_acm, bool, 0); +MODULE_PARM_DESC(use_acm, "Use CDC ACM, default=yes"); + +static bool use_obex = false; +module_param(use_obex, bool, 0); +MODULE_PARM_DESC(use_obex, "Use CDC OBEX, default=no"); + +static unsigned n_ports = 1; +module_param(n_ports, uint, 0); +MODULE_PARM_DESC(n_ports, "number of ports to create, default=1"); + +static bool enable = true; + +static int switch_gserial_enable(bool do_enable); + +static int enable_set(const char *s, const struct kernel_param *kp) +{ + bool do_enable; + int ret; + + if (!s) /* called for no-arg enable == default */ + return 0; + + ret = strtobool(s, &do_enable); + if (ret || enable == do_enable) + return ret; + + ret = switch_gserial_enable(do_enable); + if (!ret) + enable = do_enable; + + return ret; +} + +static const struct kernel_param_ops enable_ops = { + .set = enable_set, + .get = param_get_bool, +}; + +module_param_cb(enable, &enable_ops, &enable, 0644); + +/*-------------------------------------------------------------------------*/ + +static struct usb_configuration serial_config_driver = { + /* .label = f(use_acm) */ + /* .bConfigurationValue = f(use_acm) */ + /* .iConfiguration = DYNAMIC */ + .bmAttributes = USB_CONFIG_ATT_SELFPOWER, +}; + +static struct usb_function_instance *fi_serial[MAX_U_SERIAL_PORTS]; +static struct usb_function *f_serial[MAX_U_SERIAL_PORTS]; + +static int serial_register_ports(struct usb_composite_dev *cdev, + struct usb_configuration *c, const char *f_name) +{ + int i; + int ret; + + ret = usb_add_config_only(cdev, c); + if (ret) + goto out; + + for (i = 0; i < n_ports; i++) { + + fi_serial[i] = usb_get_function_instance(f_name); + if (IS_ERR(fi_serial[i])) { + ret = PTR_ERR(fi_serial[i]); + goto fail; + } + + f_serial[i] = usb_get_function(fi_serial[i]); + if (IS_ERR(f_serial[i])) { + ret = PTR_ERR(f_serial[i]); + goto err_get_func; + } + + ret = usb_add_function(c, f_serial[i]); + if (ret) + goto err_add_func; + } + + return 0; + +err_add_func: + usb_put_function(f_serial[i]); +err_get_func: + usb_put_function_instance(fi_serial[i]); + +fail: + i--; + while (i >= 0) { + usb_remove_function(c, f_serial[i]); + usb_put_function(f_serial[i]); + usb_put_function_instance(fi_serial[i]); + i--; + } +out: + return ret; +} + +static int gs_bind(struct usb_composite_dev *cdev) +{ + int status; + + /* Allocate string descriptor numbers ... note that string + * contents can be overridden by the composite_dev glue. + */ + + status = usb_string_ids_tab(cdev, strings_dev); + if (status < 0) + goto fail; + device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id; + device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id; + status = strings_dev[STRING_DESCRIPTION_IDX].id; + serial_config_driver.iConfiguration = status; + + if (gadget_is_otg(cdev->gadget)) { + if (!otg_desc[0]) { + struct usb_descriptor_header *usb_desc; + + usb_desc = usb_otg_descriptor_alloc(cdev->gadget); + if (!usb_desc) { + status = -ENOMEM; + goto fail; + } + usb_otg_descriptor_init(cdev->gadget, usb_desc); + otg_desc[0] = usb_desc; + otg_desc[1] = NULL; + } + serial_config_driver.descriptors = otg_desc; + serial_config_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP; + } + + /* register our configuration */ + if (use_acm) { + status = serial_register_ports(cdev, &serial_config_driver, + "acm"); + usb_ep_autoconfig_reset(cdev->gadget); + } else if (use_obex) + status = serial_register_ports(cdev, &serial_config_driver, + "obex"); + else { + status = serial_register_ports(cdev, &serial_config_driver, + "gser"); + } + if (status < 0) + goto fail1; + + usb_composite_overwrite_options(cdev, &coverwrite); + INFO(cdev, "%s\n", GS_VERSION_NAME); + + return 0; +fail1: + kfree(otg_desc[0]); + otg_desc[0] = NULL; +fail: + return status; +} + +static int gs_unbind(struct usb_composite_dev *cdev) +{ + int i; + + for (i = 0; i < n_ports; i++) { + usb_put_function(f_serial[i]); + usb_put_function_instance(fi_serial[i]); + } + + kfree(otg_desc[0]); + otg_desc[0] = NULL; + + return 0; +} + +static struct usb_composite_driver gserial_driver = { + .name = "g_serial", + .dev = &device_desc, + .strings = dev_strings, + .max_speed = USB_SPEED_SUPER, + .bind = gs_bind, + .unbind = gs_unbind, +}; + +static int switch_gserial_enable(bool do_enable) +{ + if (!serial_config_driver.label) + /* gserial_init() was not called, yet */ + return 0; + + if (do_enable) + return usb_composite_probe(&gserial_driver); + + usb_composite_unregister(&gserial_driver); + return 0; +} + +static int __init gserial_init(void) +{ + /* We *could* export two configs; that'd be much cleaner... + * but neither of these product IDs was defined that way. + */ + if (use_acm) { + serial_config_driver.label = "CDC ACM config"; + serial_config_driver.bConfigurationValue = 2; + device_desc.bDeviceClass = USB_CLASS_COMM; + device_desc.idProduct = + cpu_to_le16(GS_CDC_PRODUCT_ID); + } else if (use_obex) { + serial_config_driver.label = "CDC OBEX config"; + serial_config_driver.bConfigurationValue = 3; + device_desc.bDeviceClass = USB_CLASS_COMM; + device_desc.idProduct = + cpu_to_le16(GS_CDC_OBEX_PRODUCT_ID); + } else { + serial_config_driver.label = "Generic Serial config"; + serial_config_driver.bConfigurationValue = 1; + device_desc.bDeviceClass = USB_CLASS_VENDOR_SPEC; + device_desc.idProduct = + cpu_to_le16(GS_PRODUCT_ID); + } + strings_dev[STRING_DESCRIPTION_IDX].s = serial_config_driver.label; + + if (!enable) + return 0; + + return usb_composite_probe(&gserial_driver); +} +module_init(gserial_init); + +static void __exit gserial_cleanup(void) +{ + if (enable) + usb_composite_unregister(&gserial_driver); +} +module_exit(gserial_cleanup); |