Commit 0df28607 authored by Daniel Scally's avatar Daniel Scally Committed by Greg Kroah-Hartman
Browse files

usb: gadget: uvc: Generalise helper functions for reuse 



The __uvcg_*frm_intrv() helper functions can be helpful when adding
support for similar attributes. Generalise the functions and
move them higher in the file for better coverage.

Signed-off-by: default avatarDaniel Scally <dan.scally@ideasonboard.com>
Link: https://lore.kernel.org/r/20230206161802.892954-3-dan.scally@ideasonboard.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent b3c839bd

drivers/usb/gadget/function/uvc_configfs.c

+67 −53
Original line number Diff line number Diff line
@@ -47,6 +47,71 @@ static int uvcg_config_compare_u32(const void *l, const void *r) 
	return li < ri ? -1 : li == ri ? 0 : 1;

}



static inline int __uvcg_count_item_entries(char *buf, void *priv, unsigned int size)

{

	++*((int *)priv);

	return 0;

}



static inline int __uvcg_fill_item_entries(char *buf, void *priv, unsigned int size)

{

	unsigned int num;

	u8 **values;

	int ret;



	ret = kstrtouint(buf, 0, &num);

	if (ret)

		return ret;



	if (num != (num & GENMASK((size * 8) - 1, 0)))

		return -ERANGE;



	values = priv;

	memcpy(*values, &num, size);

	*values += size;



	return 0;

}



static int __uvcg_iter_item_entries(const char *page, size_t len,

				    int (*fun)(char *, void *, unsigned int),

				    void *priv, unsigned int size)

{

	/* sign, base 2 representation, newline, terminator */

	unsigned int bufsize = 1 + size * 8 + 1 + 1;

	const char *pg = page;

	int i, ret = 0;

	char *buf;



	if (!fun)

		return -EINVAL;



	buf = kzalloc(bufsize, GFP_KERNEL);

	if (!buf)

		return -ENOMEM;



	while (pg - page < len) {

		i = 0;

		while (i < sizeof(buf) && (pg - page < len) &&

		       *pg != '\0' && *pg != '\n')

			buf[i++] = *pg++;

		if (i == sizeof(buf)) {

			ret = -EINVAL;

			goto out_free_buf;

		}

		while ((pg - page < len) && (*pg == '\0' || *pg == '\n'))

			++pg;

		buf[i] = '\0';

		ret = fun(buf, priv, size);

		if (ret)

			goto out_free_buf;

	}



out_free_buf:

	kfree(buf);

	return ret;

}



struct uvcg_config_group_type {

	struct config_item_type type;

	const char *name;
@@ -1336,57 +1401,6 @@ static ssize_t uvcg_frame_dw_frame_interval_show(struct config_item *item, 
	return result;

}



static inline int __uvcg_count_frm_intrv(char *buf, void *priv)

{

	++*((int *)priv);

	return 0;

}



static inline int __uvcg_fill_frm_intrv(char *buf, void *priv)

{

	u32 num, **interv;

	int ret;



	ret = kstrtou32(buf, 0, &num);

	if (ret)

		return ret;



	interv = priv;

	**interv = num;

	++*interv;



	return 0;

}



static int __uvcg_iter_frm_intrv(const char *page, size_t len,

				 int (*fun)(char *, void *), void *priv)

{

	/* sign, base 2 representation, newline, terminator */

	char buf[1 + sizeof(u32) * 8 + 1 + 1];

	const char *pg = page;

	int i, ret;



	if (!fun)

		return -EINVAL;



	while (pg - page < len) {

		i = 0;

		while (i < sizeof(buf) && (pg - page < len) &&

				*pg != '\0' && *pg != '\n')

			buf[i++] = *pg++;

		if (i == sizeof(buf))

			return -EINVAL;

		while ((pg - page < len) && (*pg == '\0' || *pg == '\n'))

			++pg;

		buf[i] = '\0';

		ret = fun(buf, priv);

		if (ret)

			return ret;

	}



	return 0;

}



static ssize_t uvcg_frame_dw_frame_interval_store(struct config_item *item,

						  const char *page, size_t len)

{
@@ -1410,7 +1424,7 @@ static ssize_t uvcg_frame_dw_frame_interval_store(struct config_item *item, 
		goto end;

	}



	ret = __uvcg_iter_frm_intrv(page, len, __uvcg_count_frm_intrv, &n);

	ret = __uvcg_iter_item_entries(page, len, __uvcg_count_item_entries, &n, sizeof(u32));

	if (ret)

		goto end;
@@ -1420,7 +1434,7 @@ static ssize_t uvcg_frame_dw_frame_interval_store(struct config_item *item, 
		goto end;

	}



	ret = __uvcg_iter_frm_intrv(page, len, __uvcg_fill_frm_intrv, &tmp);

	ret = __uvcg_iter_item_entries(page, len, __uvcg_fill_item_entries, &tmp, sizeof(u32));

	if (ret) {

		kfree(frm_intrv);

		goto end;