Attach any arbitrary strings that are defined to the composite dev.
We handle the old-style manufacturer, product and serialnumbers
strings in the same function for simplicity.
Signed-off-by: Daniel Scally <dan.scally@xxxxxxxxxxxxxxxx>
---
Changes in v3:
- Was 7/9 in version 2, moved the same functionality from the UVC
function to usb gadget core.
Changes in v2:
- New patch
drivers/usb/gadget/configfs.c | 95 ++++++++++++++++++++++++++++-------
include/linux/usb/composite.h | 1 +
2 files changed, 79 insertions(+), 17 deletions(-)
diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index 7c8b8ab5dfa3..c2f23a63ab10 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -1441,6 +1441,80 @@ static void purge_configs_funcs(struct gadget_info *gi)
}
}
+static struct usb_string *
+configfs_attach_gadget_strings(struct gadget_info *gi)
+{
+ struct usb_gadget_strings **gadget_strings;
+ struct gadget_language *language;
+ struct gadget_string *string;
+ unsigned int nlangs = 0;
+ struct list_head *iter;
+ struct usb_string *us;
+ unsigned int i = 0;
+ int nstrings = -1;
+ unsigned int j;
+
+ list_for_each(iter, &gi->string_list)
+ nlangs++;
+
+ /* Bail out early if no languages are configured */
+ if (!nlangs)
+ return NULL;
+
+ gadget_strings = kcalloc(nlangs + 1, /* including NULL terminator */
+ sizeof(struct usb_gadget_strings *), GFP_KERNEL);
+ if (!gadget_strings)
+ return ERR_PTR(-ENOMEM);
+
+ list_for_each_entry(language, &gi->string_list, list) {
+ struct usb_string *stringtab;
+
+ if (nstrings == -1) {
+ nstrings = language->nstrings;
+ } else if (nstrings != language->nstrings) {
+ pr_err("languages must contain the same number of strings\n");
+ us = ERR_PTR(-EINVAL);
+ goto cleanup;
+ }
+
+ stringtab = kcalloc(language->nstrings + 1, sizeof(struct usb_string),
+ GFP_KERNEL);
+ if (!stringtab) {
+ us = ERR_PTR(-ENOMEM);
+ goto cleanup;
+ }
+
+ stringtab[USB_GADGET_MANUFACTURER_IDX].id = USB_GADGET_MANUFACTURER_IDX;
+ stringtab[USB_GADGET_MANUFACTURER_IDX].s = language->manufacturer;
+ stringtab[USB_GADGET_PRODUCT_IDX].id = USB_GADGET_PRODUCT_IDX;
+ stringtab[USB_GADGET_PRODUCT_IDX].s = language->product;
+ stringtab[USB_GADGET_SERIAL_IDX].id = USB_GADGET_SERIAL_IDX;
+ stringtab[USB_GADGET_SERIAL_IDX].s = language->serialnumber;
+
+ j = USB_GADGET_FIRST_AVAIL_IDX;
+ list_for_each_entry(string, &language->gadget_strings, list) {
+ memcpy(&stringtab[j], &string->usb_string, sizeof(struct usb_string));
+ j++;
+ }
+
+ language->stringtab_dev.strings = stringtab;
+ gadget_strings[i] = &language->stringtab_dev;
+ i++;
+ }
+
+ us = usb_gstrings_attach(&gi->cdev, gadget_strings, nstrings);
+
+cleanup:
+ list_for_each_entry(language, &gi->string_list, list) {
+ kfree(language->stringtab_dev.strings);
+ language->stringtab_dev.strings = NULL;
+ }
+
+ kfree(gadget_strings);
+
+ return us;
+}
+
static int configfs_composite_bind(struct usb_gadget *gadget,
struct usb_gadget_driver *gdriver)
{
@@ -1484,23 +1558,8 @@ static int configfs_composite_bind(struct usb_gadget *gadget,
/* init all strings */
if (!list_empty(&gi->string_list)) {
- struct gadget_language *gs;
-
- i = 0;
- list_for_each_entry(gs, &gi->string_list, list) {
-
- gi->gstrings[i] = &gs->stringtab_dev;
- gs->stringtab_dev.strings = gs->strings;
- gs->strings[USB_GADGET_MANUFACTURER_IDX].s =
- gs->manufacturer;
- gs->strings[USB_GADGET_PRODUCT_IDX].s = gs->product;
- gs->strings[USB_GADGET_SERIAL_IDX].s = gs->serialnumber;
- i++;
- }
- gi->gstrings[i] = NULL;
- s = usb_gstrings_attach(&gi->cdev, gi->gstrings,
- USB_GADGET_FIRST_AVAIL_IDX);
- if (IS_ERR(s)) {
+ s = configfs_attach_gadget_strings(gi);
+ if (IS_ERR_OR_NULL(s)) {
ret = PTR_ERR(s);
goto err_comp_cleanup;
}
@@ -1508,6 +1567,8 @@ static int configfs_composite_bind(struct usb_gadget *gadget,
gi->cdev.desc.iManufacturer = s[USB_GADGET_MANUFACTURER_IDX].id;
gi->cdev.desc.iProduct = s[USB_GADGET_PRODUCT_IDX].id;
gi->cdev.desc.iSerialNumber = s[USB_GADGET_SERIAL_IDX].id;
+
+ gi->cdev.usb_strings = s;
}
if (gi->use_os_desc) {
diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h
index 43ac3fa760db..85c7f6036933 100644
--- a/include/linux/usb/composite.h
+++ b/include/linux/usb/composite.h
@@ -483,6 +483,7 @@ struct usb_composite_dev {
struct usb_composite_driver *driver;
u8 next_string_id;
char *def_manufacturer;
+ struct usb_string *usb_strings;
/* the gadget driver won't enable the data pullup
* while the deactivation count is nonzero.
--
2.34.1
