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authorWesley Cheng2021-07-10 02:13:10 -0700
committerGreg Kroah-Hartman2021-07-12 09:37:25 +0200
commitce7d0008c2356626f69f37ef1afce8fbc83fe142 (patch)
tree303d36dde760b4e0f5a982b319e27391a937bc49
parente73f0f0ee7541171d89f2e2491130c7771ba58d3 (diff)
usb: gadget: udc: core: Introduce check_config to verify USB configuration
Some UDCs may have constraints on how many high bandwidth endpoints it can support in a certain configuration. This API allows for the composite driver to pass down the total number of endpoints to the UDC so it can verify it has the required resources to support the configuration. Signed-off-by: Wesley Cheng <wcheng@codeaurora.org> Link: https://lore.kernel.org/r/1625908395-5498-2-git-send-email-wcheng@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/gadget/udc/core.c19
-rw-r--r--include/linux/usb/gadget.h4
2 files changed, 23 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index b7f0b1ebaaa8..14fdf918ecfe 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -1003,6 +1003,25 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
}
EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
+/**
+ * usb_gadget_check_config - checks if the UDC can support the binded
+ * configuration
+ * @gadget: controller to check the USB configuration
+ *
+ * Ensure that a UDC is able to support the requested resources by a
+ * configuration, and that there are no resource limitations, such as
+ * internal memory allocated to all requested endpoints.
+ *
+ * Returns zero on success, else a negative errno.
+ */
+int usb_gadget_check_config(struct usb_gadget *gadget)
+{
+ if (gadget->ops->check_config)
+ return gadget->ops->check_config(gadget);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_check_config);
+
/* ------------------------------------------------------------------------- */
static void usb_gadget_state_work(struct work_struct *work)
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 75c7538e350a..776851e57741 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -329,6 +329,7 @@ struct usb_gadget_ops {
struct usb_ep *(*match_ep)(struct usb_gadget *,
struct usb_endpoint_descriptor *,
struct usb_ss_ep_comp_descriptor *);
+ int (*check_config)(struct usb_gadget *gadget);
};
/**
@@ -608,6 +609,7 @@ int usb_gadget_connect(struct usb_gadget *gadget);
int usb_gadget_disconnect(struct usb_gadget *gadget);
int usb_gadget_deactivate(struct usb_gadget *gadget);
int usb_gadget_activate(struct usb_gadget *gadget);
+int usb_gadget_check_config(struct usb_gadget *gadget);
#else
static inline int usb_gadget_frame_number(struct usb_gadget *gadget)
{ return 0; }
@@ -631,6 +633,8 @@ static inline int usb_gadget_deactivate(struct usb_gadget *gadget)
{ return 0; }
static inline int usb_gadget_activate(struct usb_gadget *gadget)
{ return 0; }
+static inline int usb_gadget_check_config(struct usb_gadget *gadget)
+{ return 0; }
#endif /* CONFIG_USB_GADGET */
/*-------------------------------------------------------------------------*/