greybus: kill struct gmod_cport

A UniPro (short header) segment has a 5-bit field to represent a
CPort Id.  In addition, the 7-bit L3 short header holds a UniPro
device id.  There can be no more than 128 devices in a UniPro
network, but these two fields can be combined in ways to allow for
over 2000 CPorts within a single device.  As a result, a device id
is represented with one byte, and a CPort Id within a device is
always representable with a two byte value.

This patch changes integral values that reresent CPort Ids so they
use type u16 consistently.

Separately, the contents of the gmod_cport structure were mostly
fabricated, with the cport_id field being the only one that's
meaningful.  This patch gets rid of that structure, putting a
simple u16 to represent the CPort Id everywhere it had been used
before.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/staging/greybus/core.c

@@ -160,8 +160,6 @@ static void greybus_module_release(struct device *dev)
 
 	for (i = 0; i < gmod->num_strings; ++i)
 		kfree(gmod->string[i]);
-	for (i = 0; i < gmod->num_cports; ++i)
-		kfree(gmod->cport[i]);
 	kfree(gmod);
 }
 
@@ -298,8 +296,6 @@ static int create_cport(struct greybus_module *gmod,
 			struct greybus_descriptor_cport *cport,
 			size_t desc_size)
 {
-	struct gmod_cport *gmod_cport;
-
 	if (gmod->num_cports == MAX_CPORTS_PER_MODULE) {
 		dev_err(gmod->dev.parent, "too many cports for this module!\n");
 		return -EINVAL;
@@ -311,15 +307,7 @@ static int create_cport(struct greybus_module *gmod,
 		return -EINVAL;
 	}
 
-	gmod_cport = kzalloc(sizeof(*gmod_cport), GFP_KERNEL);
-	if (!gmod_cport)
-		return -ENOMEM;
-
-	gmod_cport->id = le16_to_cpu(cport->id);
-	gmod_cport->size = le16_to_cpu(cport->size);
-	gmod_cport->speed = cport->speed;
-
-	gmod->cport[gmod->num_cports] = gmod_cport;
+	gmod->cport_ids[gmod->num_cports] = le16_to_cpu(cport->id);
 	gmod->num_cports++;
 
 	return 0;

drivers/staging/greybus/es1-ap-usb.c

@@ -11,8 +11,10 @@
 #include <linux/errno.h>
 #include <linux/sizes.h>
 #include <linux/usb.h>
+
 #include "greybus.h"
 #include "svc_msg.h"
+#include "kernel_ver.h"
 
 /* Memory sizes for the buffers sent to/from the ES1 controller */
 #define ES1_SVC_MSG_SIZE	(sizeof(struct svc_msg) + SZ_64K)
@@ -114,7 +116,8 @@ static int alloc_gbuf_data(struct gbuf *gbuf, unsigned int size, gfp_t gfp_mask)
 	 * we will encode the cport number in the first byte of the buffer, so
 	 * set the second byte to be the "transfer buffer"
 	 */
-	buffer[0] = gbuf->cport->id;
+	BUG_ON(gbuf->cport_id > (u16)U8_MAX);
+	buffer[0] = gbuf->cport_id;
 	gbuf->transfer_buffer = &buffer[1];
 	gbuf->transfer_buffer_length = size;
 	gbuf->actual_length = size;

drivers/staging/greybus/gbuf.c

@@ -27,7 +27,7 @@ static struct kmem_cache *gbuf_head_cache;
 static struct workqueue_struct *gbuf_workqueue;
 
 static struct gbuf *__alloc_gbuf(struct greybus_module *gmod,
-				struct gmod_cport *cport,
+				u16 cport_id,
 				gbuf_complete_t complete,
 				gfp_t gfp_mask,
 				void *context)
@@ -40,7 +40,7 @@ static struct gbuf *__alloc_gbuf(struct greybus_module *gmod,
 
 	kref_init(&gbuf->kref);
 	gbuf->gmod = gmod;
-	gbuf->cport = cport;
+	gbuf->cport_id = cport_id;
 	INIT_WORK(&gbuf->event, cport_process_event);
 	gbuf->complete = complete;
 	gbuf->context = context;
@@ -64,7 +64,7 @@ static struct gbuf *__alloc_gbuf(struct greybus_module *gmod,
  * hardware designers for this issue...
  */
 struct gbuf *greybus_alloc_gbuf(struct greybus_module *gmod,
-				struct gmod_cport *cport,
+				u16 cport_id,
 				gbuf_complete_t complete,
 				unsigned int size,
 				gfp_t gfp_mask,
@@ -73,7 +73,7 @@ struct gbuf *greybus_alloc_gbuf(struct greybus_module *gmod,
 	struct gbuf *gbuf;
 	int retval;
 
-	gbuf = __alloc_gbuf(gmod, cport, complete, gfp_mask, context);
+	gbuf = __alloc_gbuf(gmod, cport_id, complete, gfp_mask, context);
 	if (!gbuf)
 		return NULL;
 
@@ -146,7 +146,7 @@ static void cport_process_event(struct work_struct *work)
 #define MAX_CPORTS	1024
 struct gb_cport_handler {
 	gbuf_complete_t handler;
-	struct gmod_cport cport;
+	u16 cport_id;
 	struct greybus_module *gmod;
 	void *context;
 };
@@ -156,25 +156,25 @@ static struct gb_cport_handler cport_handler[MAX_CPORTS];
 // need it, we don't have a dynamic system...
 
 int gb_register_cport_complete(struct greybus_module *gmod,
-			       gbuf_complete_t handler, int cport_id,
+			       gbuf_complete_t handler, u16 cport_id,
 			       void *context)
 {
 	if (cport_handler[cport_id].handler)
 		return -EINVAL;
 	cport_handler[cport_id].context = context;
 	cport_handler[cport_id].gmod = gmod;
-	cport_handler[cport_id].cport.id = cport_id;
+	cport_handler[cport_id].cport_id = cport_id;
 	cport_handler[cport_id].handler = handler;
 	return 0;
 }
 
-void gb_deregister_cport_complete(int cport_id)
+void gb_deregister_cport_complete(u16 cport_id)
 {
 	cport_handler[cport_id].handler = NULL;
 }
 
-void greybus_cport_in(struct greybus_host_device *hd, int cport_id, u8 *data,
-			   size_t length)
+void greybus_cport_in(struct greybus_host_device *hd, u16 cport_id,
+			u8 *data, size_t length)
 {
 	struct gb_cport_handler *ch;
 	struct gbuf *gbuf;
@@ -189,7 +189,7 @@ void greybus_cport_in(struct greybus_host_device *hd, int cport_id, u8 *data,
 		return;
 	}
 
-	gbuf = __alloc_gbuf(ch->gmod, &ch->cport, ch->handler, GFP_ATOMIC,
+	gbuf = __alloc_gbuf(ch->gmod, ch->cport_id, ch->handler, GFP_ATOMIC,
 			ch->context);
 	if (!gbuf) {
 		/* Again, something bad went wrong, log it... */

drivers/staging/greybus/greybus.h

@@ -101,13 +101,6 @@
 
 struct gbuf;
 
-struct gmod_cport {
-	u16	id;
-	u16	size;
-	u8	speed;	// valid???
-	// FIXME, what else?
-};
-
 struct gmod_string {
 	u16	length;
 	u8	id;
@@ -121,7 +114,7 @@ struct gbuf {
 	void *hdpriv;
 
 	struct greybus_module *gmod;
-	struct gmod_cport *cport;
+	u16 cport_id;
 	int status;
 	void *transfer_buffer;
 	u32 transfer_flags;		/* flags for the transfer buffer */
@@ -187,8 +180,8 @@ struct greybus_host_device {
 struct greybus_host_device *greybus_create_hd(struct greybus_host_driver *host_driver,
 					      struct device *parent);
 void greybus_remove_hd(struct greybus_host_device *hd);
-void greybus_cport_in(struct greybus_host_device *hd, int cport_id, u8 *data,
-			   size_t length);
+void greybus_cport_in(struct greybus_host_device *hd, u16 cport_id,
+			u8 *data, size_t length);
 void greybus_gbuf_finished(struct gbuf *gbuf);
 
 
@@ -203,7 +196,7 @@ struct greybus_module {
 	struct greybus_descriptor_module module;
 	int num_cports;
 	int num_strings;
-	struct gmod_cport *cport[MAX_CPORTS_PER_MODULE];
+	u16 cport_ids[MAX_CPORTS_PER_MODULE];
 	struct gmod_string *string[MAX_STRINGS_PER_MODULE];
 
 	struct greybus_host_device *hd;
@@ -218,7 +211,7 @@ struct greybus_module {
 #define to_greybus_module(d) container_of(d, struct greybus_module, dev)
 
 struct gbuf *greybus_alloc_gbuf(struct greybus_module *gmod,
-				struct gmod_cport *cport,
+				u16 cport_id,
 				gbuf_complete_t complete,
 				unsigned int size,
 				gfp_t gfp_mask,
@@ -298,9 +291,9 @@ int gb_gbuf_init(void);
 void gb_gbuf_exit(void);
 
 int gb_register_cport_complete(struct greybus_module *gmod,
-			       gbuf_complete_t handler, int cport_id,
+			       gbuf_complete_t handler, u16 cport_id,
 			       void *context);
-void gb_deregister_cport_complete(int cport_id);
+void gb_deregister_cport_complete(u16 cport_id);
 
 extern const struct attribute_group *greybus_module_groups[];
 

drivers/staging/greybus/kernel_ver.h

@@ -18,5 +18,8 @@
 	struct device_attribute dev_attr_##_name = __ATTR_RO(_name)
 #endif
 
+#ifndef U8_MAX
+#define U8_MAX	((u8)~0U)
+#endif /* ! U8_MAX */
 
 #endif	/* __GREYBUS_KERNEL_VER_H */

drivers/staging/greybus/svc_msg.h

@@ -49,9 +49,9 @@ struct svc_function_handshake {
 
 struct svc_function_unipro_set_route {
 	__u8	source_module_id;
-	__u8	source_cport_id;
+	__u8	source_cport_id;	/* bottom 8 bits */
 	__u8	destination_module_id;
-	__u8	destination_cport_id;
+	__u8	destination_cport_id;	/* bottom 8 bits */
 };
 
 struct svc_function_unipro_link_up {

drivers/staging/greybus/test_sink.c

@@ -16,9 +16,9 @@ struct test_device {
 };
 
 int gb_register_cport_complete(struct greybus_module *gmod,
-			       gbuf_complete_t handler, int cport_id,
+			       gbuf_complete_t handler, u16 cport_id,
 			       void *context);
-void gb_deregister_cport_complete(int cport_id);
+void gb_deregister_cport_complete(u16 cport_id);
 
 
 

drivers/staging/greybus/uart-gb.c

@@ -34,7 +34,7 @@
 struct gb_tty {
 	struct tty_port port;
 	struct greybus_module *gmod;
-	int cport_id;
+	u16 cport_id;
 	unsigned int minor;
 	unsigned char clocal;
 	unsigned int throttled:1;