usb: gadget: f_fs: Add the missing get_alt callback
Commit Message
The Apple CarLife iAP gadget has a descriptor in userspace with two
alternate settings. The host sends the set_alt request to configure
alt_setting 0 or 1, and this is verified by the subsequent get_alt
request.
This patch implements and sets the get_alt callback. Without the
get_alt callback, composite.c abruptly concludes the
USB_REQ_GET/SET_INTERFACE request, assuming only one alt setting
for the endpoint.
unlike the uvc and ncm, f_fs gadget is fully implemented in userspace,
and driver just reset the eps and generate the event. so no additional
adaptaion associated with this change is not required in set_alt callback
Signed-off-by: Hardik Gajjar <hgajjar@de.adit-jv.com>
---
drivers/usb/gadget/function/f_fs.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
@@ -42,6 +42,7 @@
#include "configfs.h"
#define FUNCTIONFS_MAGIC 0xa647361 /* Chosen by a honest dice roll ;) */
+#define MAX_ALT_SETTINGS 2 /* Allow up to 2 alt settings to be set. */
/* Reference counter handling */
static void ffs_data_get(struct ffs_data *ffs);
@@ -75,6 +76,7 @@ struct ffs_function {
short *interfaces_nums;
struct usb_function function;
+ int cur_alt[MAX_CONFIG_INTERFACES];
};
@@ -98,6 +100,7 @@ static int __must_check ffs_func_eps_enable(struct ffs_function *func);
static int ffs_func_bind(struct usb_configuration *,
struct usb_function *);
static int ffs_func_set_alt(struct usb_function *, unsigned, unsigned);
+static int ffs_func_get_alt(struct usb_function *f, unsigned int intf);
static void ffs_func_disable(struct usb_function *);
static int ffs_func_setup(struct usb_function *,
const struct usb_ctrlrequest *);
@@ -3231,6 +3234,15 @@ static void ffs_reset_work(struct work_struct *work)
ffs_data_reset(ffs);
}
+static int ffs_func_get_alt(struct usb_function *f,
+ unsigned int interface)
+{
+ struct ffs_function *func = ffs_func_from_usb(f);
+ int intf = ffs_func_revmap_intf(func, interface);
+
+ return (intf < 0) ? intf : func->cur_alt[interface];
+}
+
static int ffs_func_set_alt(struct usb_function *f,
unsigned interface, unsigned alt)
{
@@ -3238,6 +3250,9 @@ static int ffs_func_set_alt(struct usb_function *f,
struct ffs_data *ffs = func->ffs;
int ret = 0, intf;
+ if (alt > MAX_ALT_SETTINGS)
+ return -EINVAL;
+
if (alt != (unsigned)-1) {
intf = ffs_func_revmap_intf(func, interface);
if (intf < 0)
@@ -3265,8 +3280,10 @@ static int ffs_func_set_alt(struct usb_function *f,
ffs->func = func;
ret = ffs_func_eps_enable(func);
- if (ret >= 0)
+ if (ret >= 0) {
ffs_event_add(ffs, FUNCTIONFS_ENABLE);
+ func->cur_alt[interface] = alt;
+ }
return ret;
}
@@ -3573,6 +3590,7 @@ static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
func->function.bind = ffs_func_bind;
func->function.unbind = ffs_func_unbind;
func->function.set_alt = ffs_func_set_alt;
+ func->function.get_alt = ffs_func_get_alt;
func->function.disable = ffs_func_disable;
func->function.setup = ffs_func_setup;
func->function.req_match = ffs_func_req_match;