Input: iqs626a - prohibit inlining of channel parsing functions

Some automated builds report a stack frame size in excess of 2 kB for
iqs626_probe(); the culprit appears to be the call to iqs626_parse_prop().

To solve this problem, specify noinline_for_stack for all of the
iqs626_parse_*() helper functions which are called inside a for loop
within iqs626_parse_prop().

As a result, a build with '-Wframe-larger-than' as low as 512 is free of
any such warnings.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/20211129004104.453930-1-jeff@labundy.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/misc/iqs626a.c

@@ -456,9 +456,10 @@ struct iqs626_private {
 	unsigned int suspend_mode;
 };
 
-static int iqs626_parse_events(struct iqs626_private *iqs626,
-			       const struct fwnode_handle *ch_node,
-			       enum iqs626_ch_id ch_id)
+static noinline_for_stack int
+iqs626_parse_events(struct iqs626_private *iqs626,
+		    const struct fwnode_handle *ch_node,
+		    enum iqs626_ch_id ch_id)
 {
 	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
 	struct i2c_client *client = iqs626->client;
@@ -604,9 +605,10 @@ static int iqs626_parse_events(struct iqs626_private *iqs626,
 	return 0;
 }
 
-static int iqs626_parse_ati_target(struct iqs626_private *iqs626,
-				   const struct fwnode_handle *ch_node,
-				   enum iqs626_ch_id ch_id)
+static noinline_for_stack int
+iqs626_parse_ati_target(struct iqs626_private *iqs626,
+			const struct fwnode_handle *ch_node,
+			enum iqs626_ch_id ch_id)
 {
 	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
 	struct i2c_client *client = iqs626->client;
@@ -885,9 +887,10 @@ static int iqs626_parse_trackpad(struct iqs626_private *iqs626,
 	return 0;
 }
 
-static int iqs626_parse_channel(struct iqs626_private *iqs626,
-				const struct fwnode_handle *ch_node,
-				enum iqs626_ch_id ch_id)
+static noinline_for_stack int
+iqs626_parse_channel(struct iqs626_private *iqs626,
+		     const struct fwnode_handle *ch_node,
+		     enum iqs626_ch_id ch_id)
 {
 	struct iqs626_sys_reg *sys_reg = &iqs626->sys_reg;
 	struct i2c_client *client = iqs626->client;