Input: db9 - store object at correct index

The variable i is used to check the port to attach to and we are
supposed to save the reference of struct db9 in the location given by
db9_base[i]. But after finding out the index, i is getting modified again
so we saved in a wrong index.
While at it mark db9_base[i] as NULL after it is freed.

Fixes: 2260c419b52b ("Input: db9 - use parallel port device model")
Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/drivers/input/joystick/db9.c b/drivers/input/joystick/db9.c
index cf1f602e0f0a46abf8266e53a20081a39c567ed0..932d07307454bd47441da61ff06e3ef03ea93cd4 100644 (file)
--- a/drivers/input/joystick/db9.c
+++ b/drivers/input/joystick/db9.c
@@ -560,25 +560,25 @@ static void db9_attach(struct parport *pp)
        const struct db9_mode_data *db9_mode;
        struct pardevice *pd;
        struct input_dev *input_dev;
-       int i, j;
+       int i, j, port_idx;
        int mode;
        struct pardev_cb db9_parport_cb;
 
-       for (i = 0; i < DB9_MAX_PORTS; i++) {
-               if (db9_cfg[i].nargs == 0 ||
-                   db9_cfg[i].args[DB9_ARG_PARPORT] < 0)
+       for (port_idx = 0; port_idx < DB9_MAX_PORTS; port_idx++) {
+               if (db9_cfg[port_idx].nargs == 0 ||
+                   db9_cfg[port_idx].args[DB9_ARG_PARPORT] < 0)
                        continue;
 
-               if (db9_cfg[i].args[DB9_ARG_PARPORT] == pp->number)
+               if (db9_cfg[port_idx].args[DB9_ARG_PARPORT] == pp->number)
                        break;
        }
 
-       if (i == DB9_MAX_PORTS) {
+       if (port_idx == DB9_MAX_PORTS) {
                pr_debug("Not using parport%d.\n", pp->number);
                return;
        }
 
-       mode = db9_cfg[i].args[DB9_ARG_MODE];
+       mode = db9_cfg[port_idx].args[DB9_ARG_MODE];
 
        if (mode < 1 || mode >= DB9_MAX_PAD || !db9_modes[mode].n_buttons) {
                printk(KERN_ERR "db9.c: Bad device type %d\n", mode);
@@ -594,7 +594,7 @@ static void db9_attach(struct parport *pp)
 
        db9_parport_cb.flags = PARPORT_FLAG_EXCL;
 
-       pd = parport_register_dev_model(pp, "db9", &db9_parport_cb, i);
+       pd = parport_register_dev_model(pp, "db9", &db9_parport_cb, port_idx);
        if (!pd) {
                printk(KERN_ERR "db9.c: parport busy already - lp.o loaded?\n");
                return;
@@ -649,7 +649,7 @@ static void db9_attach(struct parport *pp)
                        goto err_free_dev;
        }
 
-       db9_base[i] = db9;
+       db9_base[port_idx] = db9;
        return;
 
  err_free_dev:
@@ -676,6 +676,7 @@ static void db9_detach(struct parport *port)
                return;
 
        db9 = db9_base[i];
+       db9_base[i] = NULL;
 
        for (i = 0; i < min(db9_modes[db9->mode].n_pads, DB9_MAX_DEVICES); i++)
                input_unregister_device(db9->dev[i]);