Commit 48767a4e authored by Tatyana Brokhman's avatar Tatyana Brokhman Committed by Greg Kroah-Hartman

usb: gadget: configure endpoint according to gadget speed

Add config_ep_by_speed() to configure the endpoint
according to the gadget speed.

Using this function will spare the FDs from handling
the endpoint chosen descriptor.
Signed-off-by: default avatarTatyana Brokhman <tlinder@codeaurora.org>
Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 72c973dd
......@@ -74,6 +74,91 @@ MODULE_PARM_DESC(iSerialNumber, "SerialNumber string");
static char composite_manufacturer[50];
/*-------------------------------------------------------------------------*/
/**
* next_ep_desc() - advance to the next EP descriptor
* @t: currect pointer within descriptor array
*
* Return: next EP descriptor or NULL
*
* Iterate over @t until either EP descriptor found or
* NULL (that indicates end of list) encountered
*/
static struct usb_descriptor_header**
next_ep_desc(struct usb_descriptor_header **t)
{
for (; *t; t++) {
if ((*t)->bDescriptorType == USB_DT_ENDPOINT)
return t;
}
return NULL;
}
/*
* for_each_ep_desc()- iterate over endpoint descriptors in the
* descriptors list
* @start: pointer within descriptor array.
* @ep_desc: endpoint descriptor to use as the loop cursor
*/
#define for_each_ep_desc(start, ep_desc) \
for (ep_desc = next_ep_desc(start); \
ep_desc; ep_desc = next_ep_desc(ep_desc+1))
/**
* config_ep_by_speed() - configures the given endpoint
* according to gadget speed.
* @g: pointer to the gadget
* @f: usb function
* @_ep: the endpoint to configure
*
* Return: error code, 0 on success
*
* This function chooses the right descriptors for a given
* endpoint according to gadget speed and saves it in the
* endpoint desc field. If the endpoint already has a descriptor
* assigned to it - overwrites it with currently corresponding
* descriptor. The endpoint maxpacket field is updated according
* to the chosen descriptor.
* Note: the supplied function should hold all the descriptors
* for supported speeds
*/
int config_ep_by_speed(struct usb_gadget *g,
struct usb_function *f,
struct usb_ep *_ep)
{
struct usb_endpoint_descriptor *chosen_desc = NULL;
struct usb_descriptor_header **speed_desc = NULL;
struct usb_descriptor_header **d_spd; /* cursor for speed desc */
if (!g || !f || !_ep)
return -EIO;
/* select desired speed */
switch (g->speed) {
case USB_SPEED_HIGH:
if (gadget_is_dualspeed(g)) {
speed_desc = f->hs_descriptors;
break;
}
/* else: fall through */
default:
speed_desc = f->descriptors;
}
/* find descriptors */
for_each_ep_desc(speed_desc, d_spd) {
chosen_desc = (struct usb_endpoint_descriptor *)*d_spd;
if (chosen_desc->bEndpointAddress == _ep->address)
goto ep_found;
}
return -EIO;
ep_found:
/* commit results */
_ep->maxpacket = le16_to_cpu(chosen_desc->wMaxPacketSize);
_ep->desc = chosen_desc;
return 0;
}
/**
* usb_add_function() - add a function to a configuration
......
......@@ -191,6 +191,7 @@ ep_matches (
size = 64;
desc->wMaxPacketSize = cpu_to_le16(size);
}
ep->address = desc->bEndpointAddress;
return 1;
}
......
......@@ -145,6 +145,9 @@ int usb_function_activate(struct usb_function *);
int usb_interface_id(struct usb_configuration *, struct usb_function *);
int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f,
struct usb_ep *_ep);
/**
* ep_choose - select descriptor endpoint at current device speed
* @g: gadget, connected and running at some speed
......
......@@ -133,6 +133,8 @@ struct usb_ep_ops {
* value can sometimes be reduced (hardware allowing), according to
* the endpoint descriptor used to configure the endpoint.
* @driver_data:for use by the gadget driver.
* @address: used to identify the endpoint when finding descriptor that
* matches connection speed
* @desc: endpoint descriptor. This pointer is set before the endpoint is
* enabled and remains valid until the endpoint is disabled.
*
......@@ -147,6 +149,7 @@ struct usb_ep {
const struct usb_ep_ops *ops;
struct list_head ep_list;
unsigned maxpacket:16;
u8 address;
const struct usb_endpoint_descriptor *desc;
};
......
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