usb: gadget: uvc: configfs: Fix operation on big endian platforms

USB descriptors are stored in little endian, requiring the use of
conversion macros. Those macros are incorrectly used for values stored
in native endian structures within the driver. Operation on big endian
platforms is thus broken. Fix it by removing the conversion macros where
they're not needed.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Tested-by: Paul Elder <paul.elder@ideasonboard.com>

drivers/usb/gadget/function/uvc_configfs.c

@@ -1105,7 +1105,7 @@ static struct uvcg_frame *to_uvcg_frame(struct config_item *item)
 	return container_of(item, struct uvcg_frame, item);
 }
 
-#define UVCG_FRAME_ATTR(cname, aname, to_cpu_endian, to_little_endian, bits) \
+#define UVCG_FRAME_ATTR(cname, aname, bits) \
 static ssize_t uvcg_frame_##cname##_show(struct config_item *item, char *page)\
 {									\
 	struct uvcg_frame *f = to_uvcg_frame(item);			\
@@ -1120,7 +1120,7 @@ static ssize_t uvcg_frame_##cname##_show(struct config_item *item, char *page)\
 	opts = to_f_uvc_opts(opts_item);				\
 									\
 	mutex_lock(&opts->lock);					\
-	result = sprintf(page, "%d\n", to_cpu_endian(f->frame.cname));	\
+	result = sprintf(page, "%d\n", f->frame.cname);			\
 	mutex_unlock(&opts->lock);					\
 									\
 	mutex_unlock(su_mutex);						\
@@ -1154,7 +1154,7 @@ static ssize_t  uvcg_frame_##cname##_store(struct config_item *item,	\
 		goto end;						\
 	}								\
 									\
-	f->frame.cname = to_little_endian(num);				\
+	f->frame.cname = num;						\
 	ret = len;							\
 end:									\
 	mutex_unlock(&opts->lock);					\
@@ -1199,20 +1199,13 @@ out:
 
 UVC_ATTR_RO(uvcg_frame_, b_frame_index, bFrameIndex);
 
-#define noop_conversion(x) (x)
-
-UVCG_FRAME_ATTR(bm_capabilities, bmCapabilities, noop_conversion,
-		noop_conversion, 8);
-UVCG_FRAME_ATTR(w_width, wWidth, le16_to_cpu, cpu_to_le16, 16);
-UVCG_FRAME_ATTR(w_height, wHeight, le16_to_cpu, cpu_to_le16, 16);
-UVCG_FRAME_ATTR(dw_min_bit_rate, dwMinBitRate, le32_to_cpu, cpu_to_le32, 32);
-UVCG_FRAME_ATTR(dw_max_bit_rate, dwMaxBitRate, le32_to_cpu, cpu_to_le32, 32);
-UVCG_FRAME_ATTR(dw_max_video_frame_buffer_size, dwMaxVideoFrameBufferSize,
-		le32_to_cpu, cpu_to_le32, 32);
-UVCG_FRAME_ATTR(dw_default_frame_interval, dwDefaultFrameInterval,
-		le32_to_cpu, cpu_to_le32, 32);
-
-#undef noop_conversion
+UVCG_FRAME_ATTR(bm_capabilities, bmCapabilities, 8);
+UVCG_FRAME_ATTR(w_width, wWidth, 16);
+UVCG_FRAME_ATTR(w_height, wHeight, 16);
+UVCG_FRAME_ATTR(dw_min_bit_rate, dwMinBitRate, 32);
+UVCG_FRAME_ATTR(dw_max_bit_rate, dwMaxBitRate, 32);
+UVCG_FRAME_ATTR(dw_max_video_frame_buffer_size, dwMaxVideoFrameBufferSize, 32);
+UVCG_FRAME_ATTR(dw_default_frame_interval, dwDefaultFrameInterval, 32);
 
 #undef UVCG_FRAME_ATTR
 
@@ -1233,8 +1226,7 @@ static ssize_t uvcg_frame_dw_frame_interval_show(struct config_item *item,
 
 	mutex_lock(&opts->lock);
 	for (result = 0, i = 0; i < frm->frame.b_frame_interval_type; ++i) {
-		result += sprintf(pg, "%d\n",
-				  le32_to_cpu(frm->dw_frame_interval[i]));
+		result += sprintf(pg, "%d\n", frm->dw_frame_interval[i]);
 		pg = page + result;
 	}
 	mutex_unlock(&opts->lock);
@@ -1259,7 +1251,7 @@ static inline int __uvcg_fill_frm_intrv(char *buf, void *priv)
 		return ret;
 
 	interv = priv;
-	**interv = cpu_to_le32(num);
+	**interv = num;
 	++*interv;
 
 	return 0;
@@ -1381,12 +1373,12 @@ static struct config_item *uvcg_frame_make(struct config_group *group,
 
 	h->frame.b_descriptor_type		= USB_DT_CS_INTERFACE;
 	h->frame.b_frame_index			= 1;
-	h->frame.w_width			= cpu_to_le16(640);
-	h->frame.w_height			= cpu_to_le16(360);
-	h->frame.dw_min_bit_rate		= cpu_to_le32(18432000);
-	h->frame.dw_max_bit_rate		= cpu_to_le32(55296000);
-	h->frame.dw_max_video_frame_buffer_size	= cpu_to_le32(460800);
-	h->frame.dw_default_frame_interval	= cpu_to_le32(666666);
+	h->frame.w_width			= 640;
+	h->frame.w_height			= 360;
+	h->frame.dw_min_bit_rate		= 18432000;
+	h->frame.dw_max_bit_rate		= 55296000;
+	h->frame.dw_max_video_frame_buffer_size	= 460800;
+	h->frame.dw_default_frame_interval	= 666666;
 
 	opts_item = group->cg_item.ci_parent->ci_parent->ci_parent;
 	opts = to_f_uvc_opts(opts_item);
@@ -2427,7 +2419,7 @@ static struct configfs_item_operations uvc_func_item_ops = {
 	.release	= uvc_func_item_release,
 };
 
-#define UVCG_OPTS_ATTR(cname, aname, conv, str2u, uxx, vnoc, limit)	\
+#define UVCG_OPTS_ATTR(cname, aname, str2u, uxx, limit)			\
 static ssize_t f_uvc_opts_##cname##_show(				\
 	struct config_item *item, char *page)				\
 {									\
@@ -2435,7 +2427,7 @@ static ssize_t f_uvc_opts_##cname##_show(				\
 	int result;							\
 									\
 	mutex_lock(&opts->lock);					\
-	result = sprintf(page, "%d\n", conv(opts->cname));		\
+	result = sprintf(page, "%d\n", opts->cname);			\
 	mutex_unlock(&opts->lock);					\
 									\
 	return result;							\
@@ -2463,7 +2455,7 @@ f_uvc_opts_##cname##_store(struct config_item *item,			\
 		ret = -EINVAL;						\
 		goto end;						\
 	}								\
-	opts->cname = vnoc(num);					\
+	opts->cname = num;						\
 	ret = len;							\
 end:									\
 	mutex_unlock(&opts->lock);					\
@@ -2474,12 +2466,9 @@ UVC_ATTR(f_uvc_opts_, cname, cname)
 
 #define identity_conv(x) (x)
 
-UVCG_OPTS_ATTR(streaming_interval, streaming_interval, identity_conv,
-	       kstrtou8, u8, identity_conv, 16);
-UVCG_OPTS_ATTR(streaming_maxpacket, streaming_maxpacket, le16_to_cpu,
-	       kstrtou16, u16, le16_to_cpu, 3072);
-UVCG_OPTS_ATTR(streaming_maxburst, streaming_maxburst, identity_conv,
-	       kstrtou8, u8, identity_conv, 15);
+UVCG_OPTS_ATTR(streaming_interval, streaming_interval, kstrtou8, u8, 16);
+UVCG_OPTS_ATTR(streaming_maxpacket, streaming_maxpacket, kstrtou16, u16, 3072);
+UVCG_OPTS_ATTR(streaming_maxburst, streaming_maxburst, kstrtou8, u8, 15);
 
 #undef identity_conv