mei: bus: report also uuid in module alias

In order to automate modules matching add device uuid
which is reported in client enumeration, keep also
the name that is needed in for nfc distinguishing radio vendor

Report mei:name:uuid

Cc: [e-mail]
Cc: Samuel Ortiz <[e-mail]>
Signed-off-by: Tomas Winkler <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/ABI/testing/sysfs-bus-mei

···
 Contact:	Samuel Ortiz <[e-mail]>
 		[e-mail]
 Description:	Stores the same MODALIAS value emitted by uevent
-		Format: mei:<mei device name>
+		Format: mei:<mei device name>:<device uuid>:

drivers/misc/mei/bus.c

···
 #define to_mei_cl_driver(d) container_of(d, struct mei_cl_driver, driver)
 #define to_mei_cl_device(d) container_of(d, struct mei_cl_device, dev)
 
+static inline uuid_le uuid_le_cast(const __u8 uuid[16])
+{
+	return *(uuid_le *)uuid;
+}
+
 static int mei_cl_device_match(struct device *dev, struct device_driver *drv)
 {
 	struct mei_cl_device *device = to_mei_cl_device(dev);
 	struct mei_cl_driver *driver = to_mei_cl_driver(drv);
 	const struct mei_cl_device_id *id;
+	const uuid_le *uuid;
+	const char *name;
 
 	if (!device)
 		return 0;
+
+	uuid = mei_me_cl_uuid(device->me_cl);
+	name = device->name;
 
 	if (!driver || !driver->id_table)
 		return 0;
 
 	id = driver->id_table;
 
-	while (id->name[0]) {
-		if (!strncmp(dev_name(dev), id->name, sizeof(id->name)))
-			return 1;
+	while (uuid_le_cmp(NULL_UUID_LE, uuid_le_cast(id->uuid))) {
+
+		if (!uuid_le_cmp(*uuid, uuid_le_cast(id->uuid))) {
+			if (id->name[0]) {
+				if (!strncmp(name, id->name, sizeof(id->name)))
+					return 1;
+			} else {
+				return 1;
+			}
+		}
 
 		id++;
 	}
···
 
 	dev_dbg(dev, "Device probe\n");
 
-	strlcpy(id.name, dev_name(dev), sizeof(id.name));
+	strlcpy(id.name, device->name, sizeof(id.name));
 
 	return driver->probe(device, &id);
 }
···
 static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
 			     char *buf)
 {
-	int len;
+	struct mei_cl_device *device = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(device->me_cl);
+	size_t len;
 
-	len = snprintf(buf, PAGE_SIZE, "mei:%s\n", dev_name(dev));
+	len = snprintf(buf, PAGE_SIZE, "mei:%s:" MEI_CL_UUID_FMT ":",
+		device->name, MEI_CL_UUID_ARGS(uuid->b));
 
 	return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
 }
···
 
 static int mei_cl_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
-	if (add_uevent_var(env, "MODALIAS=mei:%s", dev_name(dev)))
+	struct mei_cl_device *device = to_mei_cl_device(dev);
+	const uuid_le *uuid = mei_me_cl_uuid(device->me_cl);
+
+	if (add_uevent_var(env, "MODALIAS=mei:%s:" MEI_CL_UUID_FMT ":",
+		device->name, MEI_CL_UUID_ARGS(uuid->b)))
 		return -ENOMEM;
 
 	return 0;
···
 	device->dev.bus = &mei_cl_bus_type;
 	device->dev.type = &mei_cl_device_type;
 
-	dev_set_name(&device->dev, "%s", name);
+	strlcpy(device->name, name, sizeof(device->name));
+
+	dev_set_name(&device->dev, "mei:%s:%pUl", name, mei_me_cl_uuid(me_cl));
 
 	status = device_register(&device->dev);
 	if (status) {

drivers/misc/mei/mei_dev.h

···
  * @dev: linux driver model device pointer
  * @me_cl: me client
  * @cl: mei client
+ * @name: device name
  * @ops: ME transport ops
  * @event_work: async work to execute event callback
  * @event_cb: Drivers register this callback to get asynchronous ME
···
 
 	struct mei_me_client *me_cl;
 	struct mei_cl *cl;
+	char name[MEI_CL_NAME_SIZE];
 
 	const struct mei_cl_ops *ops;
 

drivers/nfc/mei_phy.h

···
 
 #include <linux/mei_cl_bus.h>
 #include <net/nfc/hci.h>
+#include <linux/uuid.h>
 
+#define MEI_NFC_UUID __UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50, \
+		0x94, 0xd4, 0x50, 0x26, 0x67, 0x23, 0x77, 0x5c)
 #define MEI_NFC_HEADER_SIZE 10
 #define MEI_NFC_MAX_HCI_PAYLOAD 300
 

drivers/nfc/microread/mei.c

···
 }
 
 static struct mei_cl_device_id microread_mei_tbl[] = {
-	{ MICROREAD_DRIVER_NAME },
+	{ MICROREAD_DRIVER_NAME, MEI_NFC_UUID},
 
 	/* required last entry */
 	{ }

drivers/nfc/pn544/mei.c

···
 }
 
 static struct mei_cl_device_id pn544_mei_tbl[] = {
-	{ PN544_DRIVER_NAME },
+	{ PN544_DRIVER_NAME, MEI_NFC_UUID},
 
 	/* required last entry */
 	{ }

include/linux/mod_devicetable.h

···
 
 #define MEI_CL_MODULE_PREFIX "mei:"
 #define MEI_CL_NAME_SIZE 32
+#define MEI_CL_UUID_FMT "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
+#define MEI_CL_UUID_ARGS(_u) \
+	_u[0], _u[1], _u[2], _u[3], _u[4], _u[5], _u[6], _u[7], \
+	_u[8], _u[9], _u[10], _u[11], _u[12], _u[13], _u[14], _u[15]
 
+/**
+ * struct mei_cl_device_id - MEI client device identifier
+ * @name: helper name
+ * @uuid: client uuid
+ * @driver_info: information used by the driver.
+ *
+ * identifies mei client device by uuid and name
+ */
 struct mei_cl_device_id {
 	char name[MEI_CL_NAME_SIZE];
+	__u8 uuid[16];
 	kernel_ulong_t driver_info;
 };
 

scripts/mod/devicetable-offsets.c

···
 
 	DEVID(mei_cl_device_id);
 	DEVID_FIELD(mei_cl_device_id, name);
+	DEVID_FIELD(mei_cl_device_id, uuid);
 
 	DEVID(rio_device_id);
 	DEVID_FIELD(rio_device_id, did);

scripts/mod/file2alias.c

···
 		strcat(str + len, "*");
 }
 
+static inline void add_uuid(char *str, __u8 uuid[16])
+{
+	int len = strlen(str);
+	int i;
+
+	for (i = 0; i < 16; i++)
+		sprintf(str + len + (i << 1), "%02x", uuid[i]);
+}
+
 /**
  * Check that sizeof(device_id type) are consistent with size of section
  * in .o file. If in-consistent then userspace and kernel does not agree
···
 }
 ADD_TO_DEVTABLE("cpu", cpu_feature, do_cpu_entry);
 
-/* Looks like: mei:S */
+/* Looks like: mei:S:uuid */
 static int do_mei_entry(const char *filename, void *symval,
 			char *alias)
 {
 	DEF_FIELD_ADDR(symval, mei_cl_device_id, name);
+	DEF_FIELD_ADDR(symval, mei_cl_device_id, uuid);
 
-	sprintf(alias, MEI_CL_MODULE_PREFIX "%s", *name);
+	sprintf(alias, MEI_CL_MODULE_PREFIX);
+	sprintf(alias + strlen(alias), "%s:",  (*name)[0]  ? *name : "*");
+	add_uuid(alias, *uuid);
+
+	strcat(alias, ":*");
 
 	return 1;
 }