Commit c0335632 authored by Daniel Scally's avatar Daniel Scally Committed by Greg Kroah-Hartman
Browse files

usb: gadget: configfs: Attach arbitrary strings to cdev 



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: default avatarDaniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20230206161802.892954-8-dan.scally@ideasonboard.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 15a7cf8c

drivers/usb/gadget/configfs.c

+77 −16
Original line number Diff line number Diff line
@@ -1597,6 +1597,80 @@ 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)

{
@@ -1640,22 +1714,7 @@ 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);

		s = configfs_attach_gadget_strings(gi);

		if (IS_ERR(s)) {

			ret = PTR_ERR(s);

			goto err_comp_cleanup;
@@ -1664,6 +1723,8 @@ 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_webusb) {

include/linux/usb/composite.h

+1 −0
Original line number Diff line number Diff line
@@ -494,6 +494,7 @@ 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.