[PATCH v2 2/8] Input/joystick/analog: Convert from seq_buf -> printbuf

[Kent Overstreet <kent.overstreet@gmail.com>]

seq_buf is being deprecated, this converts to printbuf which is similar
but heap allocates the string buffer.

This means we have to consider memory allocation context & failure: Here
we're in device initialization so GFP_KERNEL should be fine, and also as
we're in device initialization returning -ENOMEM is fine.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
---
 drivers/input/joystick/analog.c | 37 ++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 14 deletions(-)

diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c
index 3088c5b829..72e1e30d19 100644
--- a/drivers/input/joystick/analog.c
+++ b/drivers/input/joystick/analog.c
@@ -19,7 +19,7 @@
 #include <linux/input.h>
 #include <linux/gameport.h>
 #include <linux/jiffies.h>
-#include <linux/seq_buf.h>
+#include <linux/printbuf.h>
 #include <linux/timex.h>
 #include <linux/timekeeping.h>
 
@@ -337,26 +337,32 @@ static void analog_calibrate_timer(struct analog_port *port)
  * analog_name() constructs a name for an analog joystick.
  */
 
-static void analog_name(struct analog *analog)
+static int analog_name(struct analog *analog)
 {
-	struct seq_buf s;
+	struct printbuf buf = PRINTBUF;
+	int ret = 0;
 
-	seq_buf_init(&s, analog->name, sizeof(analog->name));
-	seq_buf_printf(&s, "Analog %d-axis %d-button",
-		 hweight8(analog->mask & ANALOG_AXES_STD),
-		 hweight8(analog->mask & ANALOG_BTNS_STD) + !!(analog->mask & ANALOG_BTNS_CHF) * 2 +
-		 hweight16(analog->mask & ANALOG_BTNS_GAMEPAD) + !!(analog->mask & ANALOG_HBTN_CHF) * 4);
+	pr_buf(&buf, "Analog %d-axis %d-button",
+	       hweight8(analog->mask & ANALOG_AXES_STD),
+	       hweight8(analog->mask & ANALOG_BTNS_STD) + !!(analog->mask & ANALOG_BTNS_CHF) * 2 +
+	       hweight16(analog->mask & ANALOG_BTNS_GAMEPAD) + !!(analog->mask & ANALOG_HBTN_CHF) * 4);
 
 	if (analog->mask & ANALOG_HATS_ALL)
-		seq_buf_printf(&s, " %d-hat",
-			       hweight16(analog->mask & ANALOG_HATS_ALL));
+		pr_buf(&buf, " %d-hat",
+		       hweight16(analog->mask & ANALOG_HATS_ALL));
 
 	if (analog->mask & ANALOG_HAT_FCS)
-		seq_buf_printf(&s, " FCS");
+		pr_buf(&buf, " FCS");
 	if (analog->mask & ANALOG_ANY_CHF)
-		seq_buf_printf(&s, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF");
+		pr_buf(&buf, (analog->mask & ANALOG_SAITEK) ? " Saitek" : " CHF");
 
-	seq_buf_printf(&s, (analog->mask & ANALOG_GAMEPAD) ? " gamepad" : " joystick");
+	pr_buf(&buf, (analog->mask & ANALOG_GAMEPAD) ? " gamepad" : " joystick");
+
+	ret = buf.allocation_failure ? -ENOMEM : 0;
+	if (!ret)
+		strlcpy(analog->name, buf.buf, sizeof(analog->name));
+	printbuf_exit(&buf);
+	return ret;
 }
 
 /*
@@ -369,7 +375,10 @@ static int analog_init_device(struct analog_port *port, struct analog *analog, i
 	int i, j, t, v, w, x, y, z;
 	int error;
 
-	analog_name(analog);
+	error = analog_name(analog);
+	if (error)
+		return error;
+
 	snprintf(analog->phys, sizeof(analog->phys),
 		 "%s/input%d", port->gameport->phys, index);
 	analog->buttons = (analog->mask & ANALOG_GAMEPAD) ? analog_pad_btn : analog_joy_btn;
-- 
2.35.2