diff options
Diffstat (limited to 'drivers/usb/gadget/function/f_serial.c')
| -rw-r--r-- | drivers/usb/gadget/function/f_serial.c | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/drivers/usb/gadget/function/f_serial.c b/drivers/usb/gadget/function/f_serial.c new file mode 100644 index 0000000..9ecbcbf --- /dev/null +++ b/drivers/usb/gadget/function/f_serial.c @@ -0,0 +1,385 @@ +/* + * f_serial.c - generic USB serial function driver + * + * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com) + * Copyright (C) 2008 by David Brownell + * Copyright (C) 2008 by Nokia Corporation + * + * This software is distributed under the terms of the GNU General + * Public License ("GPL") as published by the Free Software Foundation, + * either version 2 of that License or (at your option) any later version. + */ + +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/device.h> + +#include "u_serial.h" +#include "gadget_chips.h" + + +/* + * This function packages a simple "generic serial" port with no real + * control mechanisms, just raw data transfer over two bulk endpoints. + * + * Because it's not standardized, this isn't as interoperable as the + * CDC ACM driver. However, for many purposes it's just as functional + * if you can arrange appropriate host side drivers. + */ + +struct f_gser { + struct gserial port; + u8 data_id; + u8 port_num; +}; + +static inline struct f_gser *func_to_gser(struct usb_function *f) +{ + return container_of(f, struct f_gser, port.func); +} + +/*-------------------------------------------------------------------------*/ + +/* interface descriptor: */ + +static struct usb_interface_descriptor gser_interface_desc = { + .bLength = USB_DT_INTERFACE_SIZE, + .bDescriptorType = USB_DT_INTERFACE, + /* .bInterfaceNumber = DYNAMIC */ + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_VENDOR_SPEC, + .bInterfaceSubClass = 0, + .bInterfaceProtocol = 0, + /* .iInterface = DYNAMIC */ +}; + +/* full speed support: */ + +static struct usb_endpoint_descriptor gser_fs_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor gser_fs_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_descriptor_header *gser_fs_function[] = { + (struct usb_descriptor_header *) &gser_interface_desc, + (struct usb_descriptor_header *) &gser_fs_in_desc, + (struct usb_descriptor_header *) &gser_fs_out_desc, + NULL, +}; + +/* high speed support: */ + +static struct usb_endpoint_descriptor gser_hs_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_endpoint_descriptor gser_hs_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_descriptor_header *gser_hs_function[] = { + (struct usb_descriptor_header *) &gser_interface_desc, + (struct usb_descriptor_header *) &gser_hs_in_desc, + (struct usb_descriptor_header *) &gser_hs_out_desc, + NULL, +}; + +static struct usb_endpoint_descriptor gser_ss_in_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_endpoint_descriptor gser_ss_out_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor gser_ss_bulk_comp_desc = { + .bLength = sizeof gser_ss_bulk_comp_desc, + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, +}; + +static struct usb_descriptor_header *gser_ss_function[] = { + (struct usb_descriptor_header *) &gser_interface_desc, + (struct usb_descriptor_header *) &gser_ss_in_desc, + (struct usb_descriptor_header *) &gser_ss_bulk_comp_desc, + (struct usb_descriptor_header *) &gser_ss_out_desc, + (struct usb_descriptor_header *) &gser_ss_bulk_comp_desc, + NULL, +}; + +/* string descriptors: */ + +static struct usb_string gser_string_defs[] = { + [0].s = "Generic Serial", + { } /* end of list */ +}; + +static struct usb_gadget_strings gser_string_table = { + .language = 0x0409, /* en-us */ + .strings = gser_string_defs, +}; + +static struct usb_gadget_strings *gser_strings[] = { + &gser_string_table, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +static int gser_set_alt(struct usb_function *f, unsigned intf, unsigned alt) +{ + struct f_gser *gser = func_to_gser(f); + struct usb_composite_dev *cdev = f->config->cdev; + + /* we know alt == 0, so this is an activation or a reset */ + + if (gser->port.in->driver_data) { + DBG(cdev, "reset generic ttyGS%d\n", gser->port_num); + gserial_disconnect(&gser->port); + } + if (!gser->port.in->desc || !gser->port.out->desc) { + DBG(cdev, "activate generic ttyGS%d\n", gser->port_num); + if (config_ep_by_speed(cdev->gadget, f, gser->port.in) || + config_ep_by_speed(cdev->gadget, f, gser->port.out)) { + gser->port.in->desc = NULL; + gser->port.out->desc = NULL; + return -EINVAL; + } + } + gserial_connect(&gser->port, gser->port_num); + return 0; +} + +static void gser_disable(struct usb_function *f) +{ + struct f_gser *gser = func_to_gser(f); + struct usb_composite_dev *cdev = f->config->cdev; + + DBG(cdev, "generic ttyGS%d deactivated\n", gser->port_num); + gserial_disconnect(&gser->port); +} + +/*-------------------------------------------------------------------------*/ + +/* serial function driver setup/binding */ + +static int gser_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct f_gser *gser = func_to_gser(f); + int status; + struct usb_ep *ep; + + /* REVISIT might want instance-specific strings to help + * distinguish instances ... + */ + + /* maybe allocate device-global string ID */ + if (gser_string_defs[0].id == 0) { + status = usb_string_id(c->cdev); + if (status < 0) + return status; + gser_string_defs[0].id = status; + } + + /* allocate instance-specific interface IDs */ + status = usb_interface_id(c, f); + if (status < 0) + goto fail; + gser->data_id = status; + gser_interface_desc.bInterfaceNumber = status; + + status = -ENODEV; + + /* allocate instance-specific endpoints */ + ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_in_desc); + if (!ep) + goto fail; + gser->port.in = ep; + ep->driver_data = cdev; /* claim */ + + ep = usb_ep_autoconfig(cdev->gadget, &gser_fs_out_desc); + if (!ep) + goto fail; + gser->port.out = ep; + ep->driver_data = cdev; /* claim */ + + /* support all relevant hardware speeds... we expect that when + * hardware is dual speed, all bulk-capable endpoints work at + * both speeds + */ + gser_hs_in_desc.bEndpointAddress = gser_fs_in_desc.bEndpointAddress; + gser_hs_out_desc.bEndpointAddress = gser_fs_out_desc.bEndpointAddress; + + gser_ss_in_desc.bEndpointAddress = gser_fs_in_desc.bEndpointAddress; + gser_ss_out_desc.bEndpointAddress = gser_fs_out_desc.bEndpointAddress; + + status = usb_assign_descriptors(f, gser_fs_function, gser_hs_function, + gser_ss_function); + if (status) + goto fail; + DBG(cdev, "generic ttyGS%d: %s speed IN/%s OUT/%s\n", + gser->port_num, + gadget_is_superspeed(c->cdev->gadget) ? "super" : + gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full", + gser->port.in->name, gser->port.out->name); + return 0; + +fail: + /* we might as well release our claims on endpoints */ + if (gser->port.out) + gser->port.out->driver_data = NULL; + if (gser->port.in) + gser->port.in->driver_data = NULL; + + ERROR(cdev, "%s: can't bind, err %d\n", f->name, status); + + return status; +} + +static inline struct f_serial_opts *to_f_serial_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_serial_opts, + func_inst.group); +} + +CONFIGFS_ATTR_STRUCT(f_serial_opts); +static ssize_t f_serial_attr_show(struct config_item *item, + struct configfs_attribute *attr, + char *page) +{ + struct f_serial_opts *opts = to_f_serial_opts(item); + struct f_serial_opts_attribute *f_serial_opts_attr = + container_of(attr, struct f_serial_opts_attribute, attr); + ssize_t ret = 0; + + if (f_serial_opts_attr->show) + ret = f_serial_opts_attr->show(opts, page); + + return ret; +} + +static void serial_attr_release(struct config_item *item) +{ + struct f_serial_opts *opts = to_f_serial_opts(item); + + usb_put_function_instance(&opts->func_inst); +} + +static struct configfs_item_operations serial_item_ops = { + .release = serial_attr_release, + .show_attribute = f_serial_attr_show, +}; + +static ssize_t f_serial_port_num_show(struct f_serial_opts *opts, char *page) +{ + return sprintf(page, "%u\n", opts->port_num); +} + +static struct f_serial_opts_attribute f_serial_port_num = + __CONFIGFS_ATTR_RO(port_num, f_serial_port_num_show); + +static struct configfs_attribute *acm_attrs[] = { + &f_serial_port_num.attr, + NULL, +}; + +static struct config_item_type serial_func_type = { + .ct_item_ops = &serial_item_ops, + .ct_attrs = acm_attrs, + .ct_owner = THIS_MODULE, +}; + +static void gser_free_inst(struct usb_function_instance *f) +{ + struct f_serial_opts *opts; + + opts = container_of(f, struct f_serial_opts, func_inst); + gserial_free_line(opts->port_num); + kfree(opts); +} + +static struct usb_function_instance *gser_alloc_inst(void) +{ + struct f_serial_opts *opts; + int ret; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return ERR_PTR(-ENOMEM); + + opts->func_inst.free_func_inst = gser_free_inst; + ret = gserial_alloc_line(&opts->port_num); + if (ret) { + kfree(opts); + return ERR_PTR(ret); + } + config_group_init_type_name(&opts->func_inst.group, "", + &serial_func_type); + + return &opts->func_inst; +} + +static void gser_free(struct usb_function *f) +{ + struct f_gser *serial; + + serial = func_to_gser(f); + kfree(serial); +} + +static void gser_unbind(struct usb_configuration *c, struct usb_function *f) +{ + usb_free_all_descriptors(f); +} + +static struct usb_function *gser_alloc(struct usb_function_instance *fi) +{ + struct f_gser *gser; + struct f_serial_opts *opts; + + /* allocate and initialize one new instance */ + gser = kzalloc(sizeof(*gser), GFP_KERNEL); + if (!gser) + return ERR_PTR(-ENOMEM); + + opts = container_of(fi, struct f_serial_opts, func_inst); + + gser->port_num = opts->port_num; + + gser->port.func.name = "gser"; + gser->port.func.strings = gser_strings; + gser->port.func.bind = gser_bind; + gser->port.func.unbind = gser_unbind; + gser->port.func.set_alt = gser_set_alt; + gser->port.func.disable = gser_disable; + gser->port.func.free_func = gser_free; + + return &gser->port.func; +} + +DECLARE_USB_FUNCTION_INIT(gser, gser_alloc_inst, gser_alloc); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Al Borchers"); +MODULE_AUTHOR("David Brownell"); |
