X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fbase%2Fregmap%2Fregmap-debugfs.c;h=4a4737887ccec28ca2ee562ba73469a0e6e828df;hb=9ae3109d1d9ff367e0d0efa7073cc078edb9a372;hp=5799a0b9e6cc4168168bef46d864fbbe0db4020e;hpb=9b5186b4be26d1fb8d63a3001b2e6ff0b2e2f82f;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 5799a0b9e6cc..4a4737887cce 100644
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -30,10 +30,9 @@ static LIST_HEAD(regmap_debugfs_early_list);
 static DEFINE_MUTEX(regmap_debugfs_early_lock);
 
 /* Calculate the length of a fixed format  */
-static size_t regmap_calc_reg_len(int max_val, char *buf, size_t buf_size)
+static size_t regmap_calc_reg_len(int max_val)
 {
-	snprintf(buf, buf_size, "%x", max_val);
-	return strlen(buf);
+	return snprintf(NULL, 0, "%x", max_val);
 }
 
 static ssize_t regmap_name_read_file(struct file *file,
@@ -174,8 +173,7 @@ static inline void regmap_calc_tot_len(struct regmap *map,
 {
 	/* Calculate the length of a fixed format  */
 	if (!map->debugfs_tot_len) {
-		map->debugfs_reg_len = regmap_calc_reg_len(map->max_register,
-							   buf, count);
+		map->debugfs_reg_len = regmap_calc_reg_len(map->max_register),
 		map->debugfs_val_len = 2 * map->format.val_bytes;
 		map->debugfs_tot_len = map->debugfs_reg_len +
 			map->debugfs_val_len + 3;      /* : \n */
@@ -421,7 +419,7 @@ static ssize_t regmap_access_read_file(struct file *file,
 		return -ENOMEM;
 
 	/* Calculate the length of a fixed format  */
-	reg_len = regmap_calc_reg_len(map->max_register, buf, count);
+	reg_len = regmap_calc_reg_len(map->max_register);
 	tot_len = reg_len + 10; /* ': R W V P\n' */
 
 	for (i = 0; i <= map->max_register; i += map->reg_stride) {
@@ -432,7 +430,7 @@ static ssize_t regmap_access_read_file(struct file *file,
 		/* If we're in the region the user is trying to read */
 		if (p >= *ppos) {
 			/* ...but not beyond it */
-			if (buf_pos >= count - 1 - tot_len)
+			if (buf_pos + tot_len + 1 >= count)
 				break;
 
 			/* Format the register */
@@ -469,6 +467,87 @@ static const struct file_operations regmap_access_fops = {
 	.llseek = default_llseek,
 };
 
+static ssize_t regmap_cache_only_write_file(struct file *file,
+					    const char __user *user_buf,
+					    size_t count, loff_t *ppos)
+{
+	struct regmap *map = container_of(file->private_data,
+					  struct regmap, cache_only);
+	ssize_t result;
+	bool was_enabled, require_sync = false;
+	int err;
+
+	map->lock(map->lock_arg);
+
+	was_enabled = map->cache_only;
+
+	result = debugfs_write_file_bool(file, user_buf, count, ppos);
+	if (result < 0) {
+		map->unlock(map->lock_arg);
+		return result;
+	}
+
+	if (map->cache_only && !was_enabled) {
+		dev_warn(map->dev, "debugfs cache_only=Y forced\n");
+		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+	} else if (!map->cache_only && was_enabled) {
+		dev_warn(map->dev, "debugfs cache_only=N forced: syncing cache\n");
+		require_sync = true;
+	}
+
+	map->unlock(map->lock_arg);
+
+	if (require_sync) {
+		err = regcache_sync(map);
+		if (err)
+			dev_err(map->dev, "Failed to sync cache %d\n", err);
+	}
+
+	return result;
+}
+
+static const struct file_operations regmap_cache_only_fops = {
+	.open = simple_open,
+	.read = debugfs_read_file_bool,
+	.write = regmap_cache_only_write_file,
+};
+
+static ssize_t regmap_cache_bypass_write_file(struct file *file,
+					      const char __user *user_buf,
+					      size_t count, loff_t *ppos)
+{
+	struct regmap *map = container_of(file->private_data,
+					  struct regmap, cache_bypass);
+	ssize_t result;
+	bool was_enabled;
+
+	map->lock(map->lock_arg);
+
+	was_enabled = map->cache_bypass;
+
+	result = debugfs_write_file_bool(file, user_buf, count, ppos);
+	if (result < 0)
+		goto out;
+
+	if (map->cache_bypass && !was_enabled) {
+		dev_warn(map->dev, "debugfs cache_bypass=Y forced\n");
+		add_taint(TAINT_USER, LOCKDEP_STILL_OK);
+	} else if (!map->cache_bypass && was_enabled) {
+		dev_warn(map->dev, "debugfs cache_bypass=N forced\n");
+	}
+
+out:
+	map->unlock(map->lock_arg);
+
+	return result;
+}
+
+static const struct file_operations regmap_cache_bypass_fops = {
+	.open = simple_open,
+	.read = debugfs_read_file_bool,
+	.write = regmap_cache_bypass_write_file,
+};
+
 void regmap_debugfs_init(struct regmap *map, const char *name)
 {
 	struct rb_node *next;
@@ -518,10 +597,11 @@ void regmap_debugfs_init(struct regmap *map, const char *name)
 	if (map->max_register || regmap_readable(map, 0)) {
 		umode_t registers_mode;
 
-		if (IS_ENABLED(REGMAP_ALLOW_WRITE_DEBUGFS))
-			registers_mode = 0600;
-		else
-			registers_mode = 0400;
+#if defined(REGMAP_ALLOW_WRITE_DEBUGFS)
+		registers_mode = 0600;
+#else
+		registers_mode = 0400;
+#endif
 
 		debugfs_create_file("registers", registers_mode, map->debugfs,
 				    map, &regmap_map_fops);
@@ -530,12 +610,13 @@ void regmap_debugfs_init(struct regmap *map, const char *name)
 	}
 
 	if (map->cache_type) {
-		debugfs_create_bool("cache_only", 0400, map->debugfs,
-				    &map->cache_only);
+		debugfs_create_file("cache_only", 0600, map->debugfs,
+				    &map->cache_only, &regmap_cache_only_fops);
 		debugfs_create_bool("cache_dirty", 0400, map->debugfs,
 				    &map->cache_dirty);
-		debugfs_create_bool("cache_bypass", 0400, map->debugfs,
-				    &map->cache_bypass);
+		debugfs_create_file("cache_bypass", 0600, map->debugfs,
+				    &map->cache_bypass,
+				    &regmap_cache_bypass_fops);
 	}
 
 	next = rb_first(&map->range_tree);