[PATCH clk] clk: clkdev: add error messages for name exceeding maximum length

[Duanqiang Wen]

if one device register clkdev with dev_id or con_id
greater than maximum length, clkdev_create functions
will not return err, but clk_find functions will not
match the device, it's difficult to identify issues
for developers.So add error messages for dev_id greater
than 20 characters and con_id greater than 16 characters.

Signed-off-by: Duanqiang Wen <duanqiangwen at net-swift.com>
---
 drivers/clk/clk.c            |  6 ++++++
 drivers/clk/clkdev.c         | 11 +++++++++++
 include/linux/clk-provider.h |  1 +
 3 files changed, 18 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 2253c154a824..10d3e0d93648 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -295,6 +295,12 @@ struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
 }
 EXPORT_SYMBOL_GPL(clk_hw_get_parent);
 
+struct device *clk_hw_get_dev(const struct clk_hw *hw)
+{
+	return hw->core->dev;
+}
+EXPORT_SYMBOL_GPL(clk_hw_get_dev);
+
 static struct clk_core *__clk_lookup_subtree(const char *name,
 					     struct clk_core *core)
 {
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index ee37d0be6877..620dc1e80b48 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -158,6 +158,9 @@ vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
 	va_list ap)
 {
 	struct clk_lookup_alloc *cla;
+	struct device *dev;
+
+	dev = clk_hw_get_dev(hw);
 
 	cla = kzalloc(sizeof(*cla), GFP_KERNEL);
 	if (!cla)
@@ -165,11 +168,19 @@ vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
 
 	cla->cl.clk_hw = hw;
 	if (con_id) {
+		if (strlen(dev_fmt) >= MAX_CON_ID) {
+			pr_err("%s:con_id string cannot be greater than 16 characters\n", dev_fmt);
+			return NULL;
+		}
 		strscpy(cla->con_id, con_id, sizeof(cla->con_id));
 		cla->cl.con_id = cla->con_id;
 	}
 
 	if (dev_fmt) {
+		if (strlen(dev_fmt) >= MAX_DEV_ID) {
+			pr_err("%s:dev_id string cannot be greater than 20 characters\n", dev_fmt);
+			return NULL;
+		}
 		vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
 		cla->cl.dev_id = cla->dev_id;
 	}
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 1293c38ddb7f..88f3e3dde147 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -1318,6 +1318,7 @@ int clk_hw_set_parent(struct clk_hw *hw, struct clk_hw *new_parent);
 unsigned int __clk_get_enable_count(struct clk *clk);
 unsigned long clk_hw_get_rate(const struct clk_hw *hw);
 unsigned long clk_hw_get_flags(const struct clk_hw *hw);
+struct device *clk_hw_get_dev(const struct clk_hw *hw);
 #define clk_hw_can_set_rate_parent(hw) \
 	(clk_hw_get_flags((hw)) & CLK_SET_RATE_PARENT)
 
-- 
2.27.0