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 000000000000..9ecbcbf36a45 --- /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 ([email protected]) + * 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");  |