greybus: descriptor type updates

Some more updates to the definition of a manifest descriptor.
    - We get rid of function descriptors.  The type of function is
      easily specified with the CPort it uses.
    - Add a new interface descriptor type.
    - Clean up the CPort descriptor structure, eliminating fields
      that serve no purpose and adding the function id field

The sysfs stuff will be updated a little later to add entries
for the Greybus interfaces associated with modules.

Rearrange the order of a few things in "greybus_manifest.h".
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/staging/greybus/core.c

@@ -232,19 +232,6 @@ static const struct greybus_module_id fake_gb_id = {
 	GREYBUS_DEVICE(0x42, 0x42)
 };
 
-static int create_function(struct greybus_module *gmod,
-			   struct greybus_descriptor_function *function,
-			   size_t desc_size)
-{
-	if (desc_size != sizeof(*function)) {
-		dev_err(gmod->dev.parent, "invalid function header size %zu\n",
-			desc_size);
-		return -EINVAL;
-	}
-	memcpy(&gmod->function, function, desc_size);
-	return 0;
-}
-
 static int create_module(struct greybus_module *gmod,
 			    struct greybus_descriptor_module *module,
 			    size_t desc_size)
@@ -385,9 +372,7 @@ void gb_add_module(struct greybus_host_device *hd, u8 module_id,
 		data_size = (size_t)desc_size - sizeof(desc->header);
 
 		switch (le16_to_cpu(desc->header.type)) {
-		case GREYBUS_TYPE_FUNCTION:
-			retval = create_function(gmod, &desc->function,
-						 data_size);
+		case GREYBUS_TYPE_DEVICE:
 			break;
 
 		case GREYBUS_TYPE_MODULE:

drivers/staging/greybus/greybus.h

@@ -192,7 +192,6 @@ void greybus_gbuf_finished(struct gbuf *gbuf);
 struct greybus_module {
 	struct device dev;
 	u16 module_number;
-	struct greybus_descriptor_function function;
 	struct greybus_descriptor_module module;
 	int num_cports;
 	int num_strings;
@@ -210,12 +209,9 @@ struct greybus_module {
 };
 #define to_greybus_module(d) container_of(d, struct greybus_module, dev)
 
-struct gbuf *greybus_alloc_gbuf(struct greybus_module *gmod,
-				u16 cport_id,
-				gbuf_complete_t complete,
-				unsigned int size,
-				gfp_t gfp_mask,
-				void *context);
+struct gbuf *greybus_alloc_gbuf(struct greybus_module *gmod, u16 cport_id,
+				gbuf_complete_t complete, unsigned int size,
+				gfp_t gfp_mask, void *context);
 void greybus_free_gbuf(struct gbuf *gbuf);
 struct gbuf *greybus_get_gbuf(struct gbuf *gbuf);
 #define greybus_put_gbuf	greybus_free_gbuf

drivers/staging/greybus/greybus_manifest.h

@@ -14,26 +14,15 @@
 
 #pragma pack(push, 1)
 
-struct greybus_manifest_header {
-	__le16	size;
-	__u8	version_major;
-	__u8	version_minor;
-};
-
 enum greybus_descriptor_type {
 	GREYBUS_TYPE_INVALID		= 0x00,
 	GREYBUS_TYPE_MODULE		= 0x01,
-	GREYBUS_TYPE_FUNCTION		= 0x02,
+	GREYBUS_TYPE_DEVICE		= 0x02,
 	GREYBUS_TYPE_CLASS		= 0x03,
 	GREYBUS_TYPE_STRING		= 0x04,
 	GREYBUS_TYPE_CPORT		= 0x05,
 };
 
-struct greybus_descriptor_header {
-	__le16	size;
-	__u8	type;	/* enum greybus_descriptor_type */
-};
-
 enum greybus_function_type {
 	GREYBUS_FUNCTION_CONTROL	= 0x00,
 	GREYBUS_FUNCTION_USB		= 0x01,
@@ -51,11 +40,10 @@ enum greybus_function_type {
 	GREYBUS_FUNCTION_VENDOR		= 0xff,
 };
 
-struct greybus_descriptor_function {
-	__le16	cport;
-	__u8	function_type;	/* enum greybus_function_type */
-};
-
+/*
+ * A module descriptor describes information about a module as a
+ * whole, *not* the functions within it.
+ */
 struct greybus_descriptor_module {
 	__le16	vendor;
 	__le16	product;
@@ -65,26 +53,61 @@ struct greybus_descriptor_module {
 	__u8	product_stringid;
 };
 
+/*
+ * A UniPro device normally supports a range of 32 CPorts (0..31).
+ * It is possible to support more than this by having a UniPro
+ * switch treat one device as if it were more than one.  E.g.,
+ * allocate 3 device ids (rather than the normal--1) to physical
+ * device 5, and configure the switch to route all packets destined
+ * for "encoded" device ids 5, 6, and 7 to physical device 5.
+ * Device 5 uses the encoded device id in incoming UniPro packets to
+ * determine which bank of 32 CPorts should receive the UniPro
+ * segment.
+ *
+ * The "scale" field in this structure is used to define the number
+ * of encoded device ids should be allocated for this physical
+ * device.  Scale is normally 1, to represent 32 available CPorts.
+ * A scale value 2 represents up to 64 CPorts; scale value 3
+ * represents up to 96 CPorts, and so on.
+ */
+struct greybus_descriptor_interface {
+	__u8	id;	/* module-relative id (0..) */
+	__u8	scale;	/* indicates range of of CPorts supported */
+	/* UniPro gear, number of in/out lanes */
+};
+
+struct greybus_descriptor_cport {
+	__le16	id;
+	__u8	function_type;	/* enum greybus_function_type */
+};
+
 struct greybus_descriptor_string {
 	__u8	length;
 	__u8	id;
 	__u8	string[0];
 };
 
-struct greybus_descriptor_cport {
-	__le16	id;
+struct greybus_descriptor_header {
+	__le16	size;
+	__u8	type;	/* enum greybus_descriptor_type */
 };
 
 struct greybus_descriptor {
 	struct greybus_descriptor_header	header;
 	union {
-		struct greybus_descriptor_function	function;
 		struct greybus_descriptor_module	module;
 		struct greybus_descriptor_string	string;
+		struct greybus_descriptor_interface	interface;
 		struct greybus_descriptor_cport		cport;
 	};
 };
 
+struct greybus_manifest_header {
+	__le16	size;
+	__u8	version_major;
+	__u8	version_minor;
+};
+
 struct greybus_manifest {
 	struct greybus_manifest_header		header;
 	struct greybus_descriptor		descriptors[0];

drivers/staging/greybus/sysfs.c

@@ -20,44 +20,6 @@
 
 #include "kernel_ver.h"
 
-/* Function fields */
-#define greybus_function_attr(field)					\
-static ssize_t function_##field##_show(struct device *dev,		\
-				       struct device_attribute *attr,	\
-				       char *buf)			\
-{									\
-	struct greybus_module *gmod = to_greybus_module(dev);		\
-	return sprintf(buf, "%d\n", gmod->function.field);		\
-}									\
-static DEVICE_ATTR_RO(function_##field)
-
-greybus_function_attr(cport);
-greybus_function_attr(function_type);
-
-static struct attribute *function_attrs[] = {
-	&dev_attr_function_cport.attr,
-	&dev_attr_function_function_type.attr,
-	NULL,
-};
-
-static umode_t function_attrs_are_visible(struct kobject *kobj,
-					  struct attribute *a, int n)
-{
-	struct greybus_module *gmod = to_greybus_module(kobj_to_dev(kobj));
-
-	// FIXME - make this a dynamic structure to "know" if it really is here
-	// or not easier?
-	if (gmod->function.cport ||
-	    gmod->function.function_type)
-		return a->mode;
-	return 0;
-}
-
-static struct attribute_group function_attr_grp = {
-	.attrs =	function_attrs,
-	.is_visible =	function_attrs_are_visible,
-};
-
 /* Module fields */
 #define greybus_module_attr(field)					\
 static ssize_t module_##field##_show(struct device *dev,		\
@@ -147,7 +109,6 @@ static struct attribute_group module_attr_grp = {
 
 
 const struct attribute_group *greybus_module_groups[] = {
-	&function_attr_grp,
 	&module_attr_grp,
 	NULL,
 };