staging: unisys: move chipsetready to sysfs

Move the chipsetready proc entry to sysfs under a new directory guest. This
entry is used by Unisys application software on the guest to acknowledge
completion of specific events for integration purposes, but these
acknowledgements are not required for the guest to operate correctly.

The store function is simplified as well, to use scanf() instead of copying
the buffer and using strsep().
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/visorchipset/visorchipset_main.c

@@ -129,9 +129,6 @@ static MYPROCTYPE *PartitionType;
 #define VISORCHIPSET_DIAG_PROC_ENTRY_FN "diagdump"
 static struct proc_dir_entry *diag_proc_dir;
 
-#define VISORCHIPSET_CHIPSET_PROC_ENTRY_FN "chipsetready"
-static struct proc_dir_entry *chipset_proc_dir;
-
 #define VISORCHIPSET_PARAHOTPLUG_PROC_ENTRY_FN "parahotplug"
 static struct proc_dir_entry *parahotplug_proc_dir;
 
@@ -323,6 +320,10 @@ static ssize_t remaining_steps_store(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count);
 static DEVICE_ATTR_RW(remaining_steps);
 
+static ssize_t chipsetready_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count);
+static DEVICE_ATTR_WO(chipsetready);
+
 static struct attribute *visorchipset_install_attrs[] = {
 	&dev_attr_toolaction.attr,
 	&dev_attr_boottotool.attr,
@@ -337,8 +338,19 @@ static struct attribute_group visorchipset_install_group = {
 	.attrs = visorchipset_install_attrs
 };
 
+static struct attribute *visorchipset_guest_attrs[] = {
+	&dev_attr_chipsetready.attr,
+	NULL
+};
+
+static struct attribute_group visorchipset_guest_group = {
+	.name = "guest",
+	.attrs = visorchipset_guest_attrs
+};
+
 static const struct attribute_group *visorchipset_dev_groups[] = {
 	&visorchipset_install_group,
+	&visorchipset_guest_group,
 	NULL
 };
 
@@ -2369,49 +2381,21 @@ visorchipset_cache_free(struct kmem_cache *pool, void *p, char *fn, int ln)
 	kmem_cache_free(pool, p);
 }
 
-#define gettoken(bufp) strsep(bufp, " -\t\n")
-
-static ssize_t
-chipset_proc_write(struct file *file, const char __user *buffer,
-		   size_t count, loff_t *ppos)
+static ssize_t chipsetready_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t count)
 {
-	char buf[512];
-	char *token, *p;
+	char msgtype[64];
 
-	if (count > sizeof(buf) - 1) {
-		LOGERR("chipset_proc_write: count (%d) exceeds size of buffer (%d)",
-		     (int) count, (int) sizeof(buffer));
-		return -EINVAL;
-	}
-	if (copy_from_user(buf, buffer, count)) {
-		LOGERR("chipset_proc_write: copy_from_user failed");
-		return -EFAULT;
-	}
-	buf[count] = '\0';
-
-	p = buf;
-	token = gettoken(&p);
-
-	if (strcmp(token, "CALLHOMEDISK_MOUNTED") == 0) {
-		token = gettoken(&p);
-		/* The Call Home Disk has been mounted */
-		if (strcmp(token, "0") == 0)
+	if (sscanf(buf, "%63s", msgtype) == 1) {
+		if (strcmp(msgtype, "CALLHOMEDISK_MOUNTED") == 0)
 			chipset_events[0] = 1;
-	} else if (strcmp(token, "MODULES_LOADED") == 0) {
-		token = gettoken(&p);
-		/* All modules for the partition have been loaded */
-		if (strcmp(token, "0") == 0)
+		else if (strcmp(msgtype, "MODULES_LOADED") == 0)
 			chipset_events[1] = 1;
-	} else if (token == NULL) {
-		/* No event specified */
-		LOGERR("No event was specified to send CHIPSET_READY response");
-		return -1;
+		else
+			return -EINVAL;
 	} else {
-		/* Unsupported event specified */
-		LOGERR("%s is an invalid event for sending CHIPSET_READY response",		     token);
-		return -1;
+		return -EINVAL;
 	}
-
 	return count;
 }
 
@@ -2422,12 +2406,6 @@ visorchipset_proc_read_writeonly(struct file *file, char __user *buf,
 	return 0;
 }
 
-static const struct file_operations chipset_proc_fops = {
-	.owner = THIS_MODULE,
-	.read = visorchipset_proc_read_writeonly,
-	.write = chipset_proc_write,
-};
-
 static int __init
 visorchipset_init(void)
 {
@@ -2508,8 +2486,6 @@ visorchipset_init(void)
 
 	memset(&g_DiagMsgHdr, 0, sizeof(CONTROLVM_MESSAGE_HEADER));
 
-	chipset_proc_dir = proc_create(VISORCHIPSET_CHIPSET_PROC_ENTRY_FN,
-				       0644, ProcDir, &chipset_proc_fops);
 	memset(&g_ChipSetMsgHdr, 0, sizeof(CONTROLVM_MESSAGE_HEADER));
 
 	parahotplug_proc_dir =
@@ -2613,10 +2589,6 @@ visorchipset_exit(void)
 	}
 	memset(&g_DiagMsgHdr, 0, sizeof(CONTROLVM_MESSAGE_HEADER));
 
-	if (chipset_proc_dir) {
-		remove_proc_entry(VISORCHIPSET_CHIPSET_PROC_ENTRY_FN, ProcDir);
-		chipset_proc_dir = NULL;
-	}
 	memset(&g_ChipSetMsgHdr, 0, sizeof(CONTROLVM_MESSAGE_HEADER));
 
 	if (parahotplug_proc_dir) {