W dniu 10.02.2014 14:16, Amit Virdi pisze:
Interrupt endpoints behave quite similar to the bulk endpoints with the
difference that the endpoints expect data sending/reception request at
particular intervals till the whole data has not been transmitted.
The interrupt EP support is added to gadget zero. A new alternate setting (=2)
has been added. It has 6 endpoints (2-BULK, 2-ISOC, 2-INTERRUPT). The default
parameters are set as:
bInterval: 4
wMaxPacketSize: 1024
However, the same can be overridden through the module parameter interface.
The module parameter interface is available only in legacy mode,
that is using g_zero.ko. Both sourcesink and loopback now support
configfs.
The code is tested for HS and SS on a platform having DWC3 controller.
Signed-off-by: Amit Virdi <[email protected]>
<snip>
+static unsigned int_interval;
+static unsigned int_maxpacket;
+static unsigned int_mult;
+static unsigned int_maxburst;
For these you need appropriate configfs attributes (files).
Below there is a typical way to create the attributes.
/*
* "show" means to copy data from kernel to user;
* you get the opts pointer and copy the relevant data to the page
*/
static ssize_t f_ss_opts_pattern_show(struct f_ss_opts *opts, char *page)
{
int result;
mutex_lock(&opts->lock);
result = sprintf(page, "%d", opts->pattern);
mutex_unlock(&opts->lock);
return result;
}
/*
* "store" means to copy data from user to the kernel;
* you take data from the page and interpret it;
* if it is ok, you store it in the opts
*/
static ssize_t f_ss_opts_pattern_store(struct f_ss_opts *opts,
const char *page, size_t len)
{
int ret;
u8 num;
mutex_lock(&opts->lock);
if (opts->refcnt) {
ret = -EBUSY;
goto end;
}
ret = kstrtou8(page, 0, &num);
if (ret)
goto end;
if (num != 0 && num != 1 && num != 2) {
ret = -EINVAL;
goto end;
}
opts->pattern = num;
ret = len;
end:
mutex_unlock(&opts->lock);
return ret;
}
static struct f_ss_opts_attribute f_ss_opts_pattern =
__CONFIGFS_ATTR(pattern, S_IRUGO | S_IWUSR,
f_ss_opts_pattern_show,
f_ss_opts_pattern_store);
/*
* definitions of f_ss_opts_isoc_interval & co follow
*/
...
/*
* hereyou should create your implementations of
* f_ss_opts_int_interval_show/store & co
*/
/*
*and then attach the attributes to the config item;
* which translates to making new files appear in their
* directory
*/
static struct configfs_attribute *ss_attrs[] = {
&f_ss_opts_pattern.attr,
&f_ss_opts_isoc_interval.attr,
&f_ss_opts_isoc_maxpacket.attr,
&f_ss_opts_isoc_mult.attr,
&f_ss_opts_isoc_maxburst.attr,
&f_ss_opts_bulk_buflen.attr,
/* HERE */
&f_ss_opts_isoc_interval.attr,
NULL,
};
AP
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
