V4L/DVB (12698): em28xx: ir-kbd-i2c init data needs a persistent object

ir-kbd-i2c's ir_probe() function can be called much later (i.e. at
ir-kbd-i2c module load), than the lifetime of a struct IR_i2c_init_data
allocated off of the stack in cx18_i2c_new_ir() at registration time.
Make sure we pass a pointer to a persistent IR_i2c_init_data object at
i2c registration time.

Thanks to Brian Rogers, Dustin Mitchell, Andy Walls and Jean Delvare to
rise this question.

Before this patch, if ir-kbd-i2c were probed after em28xx, trash data
were used. After the patch, no matter what order, it is properly
reported as tested by me:

input: i2c IR (i2c IR (EM2840 Hauppaug as /class/input/input10
ir-kbd-i2c: i2c IR (i2c IR (EM2840 Hauppaug detected at i2c-4/4-0030/ir0 [em28xx #0]

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 19 insertions, 17 deletions

diff --git a/drivers/media/video/em28xx/em28xx-cards.c b/drivers/media/video/em28xx/em28xx-cards.c
index f46b8a5c3a61..c55634a674ba 100644
--- a/drivers/media/video/em28xx/em28xx-cards.c
+++ b/drivers/media/video/em28xx/em28xx-cards.c
@@ -2196,8 +2196,6 @@ static int em28xx_hint_board(struct em28xx *dev)
 /* ----------------------------------------------------------------------- */
 void em28xx_register_i2c_ir(struct em28xx *dev)
 {
-        struct i2c_board_info info;
-        struct IR_i2c_init_data init_data;
         const unsigned short addr_list[] = {
                  0x30, 0x47, I2C_CLIENT_END
         };
@@ -2205,9 +2203,9 @@ void em28xx_register_i2c_ir(struct em28xx *dev)
         if (disable_ir)
                 return;
 
-        memset(&info, 0, sizeof(struct i2c_board_info));
-        memset(&init_data, 0, sizeof(struct IR_i2c_init_data));
-        strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
+        memset(&dev->info, 0, sizeof(&dev->info));
+        memset(&dev->init_data, 0, sizeof(dev->init_data));
+        strlcpy(dev->info.type, "ir_video", I2C_NAME_SIZE);
 
         /* detect & configure */
         switch (dev->model) {
@@ -2217,19 +2215,19 @@ void em28xx_register_i2c_ir(struct em28xx *dev)
                 break;
         case (EM2800_BOARD_TERRATEC_CINERGY_200):
         case (EM2820_BOARD_TERRATEC_CINERGY_250):
-                init_data.ir_codes = &ir_codes_em_terratec_table;
-                init_data.get_key = em28xx_get_key_terratec;
-                init_data.name = "i2c IR (EM28XX Terratec)";
+                dev->init_data.ir_codes = &ir_codes_em_terratec_table;
+                dev->init_data.get_key = em28xx_get_key_terratec;
+                dev->init_data.name = "i2c IR (EM28XX Terratec)";
                 break;
         case (EM2820_BOARD_PINNACLE_USB_2):
-                init_data.ir_codes = &ir_codes_pinnacle_grey_table;
-                init_data.get_key = em28xx_get_key_pinnacle_usb_grey;
-                init_data.name = "i2c IR (EM28XX Pinnacle PCTV)";
+                dev->init_data.ir_codes = &ir_codes_pinnacle_grey_table;
+                dev->init_data.get_key = em28xx_get_key_pinnacle_usb_grey;
+                dev->init_data.name = "i2c IR (EM28XX Pinnacle PCTV)";
                 break;
         case (EM2820_BOARD_HAUPPAUGE_WINTV_USB_2):
-                init_data.ir_codes = &ir_codes_hauppauge_new_table;
-                init_data.get_key = em28xx_get_key_em_haup;
-                init_data.name = "i2c IR (EM2840 Hauppauge)";
+                dev->init_data.ir_codes = &ir_codes_hauppauge_new_table;
+                dev->init_data.get_key = em28xx_get_key_em_haup;
+                dev->init_data.name = "i2c IR (EM2840 Hauppauge)";
                 break;
         case (EM2820_BOARD_MSI_VOX_USB_2):
                 break;
@@ -2241,9 +2239,9 @@ void em28xx_register_i2c_ir(struct em28xx *dev)
                 break;
         }
 
-        if (init_data.name)
-                info.platform_data = &init_data;
-        i2c_new_probed_device(&dev->i2c_adap, &info, addr_list);
+        if (dev->init_data.name)
+                dev->info.platform_data = &dev->init_data;
+        i2c_new_probed_device(&dev->i2c_adap, &dev->info, addr_list);
 }
 
 void em28xx_card_setup(struct em28xx *dev)
diff --git a/drivers/media/video/em28xx/em28xx.h b/drivers/media/video/em28xx/em28xx.h
index 217f948e03d7..bc825bdd65be 100644
--- a/drivers/media/video/em28xx/em28xx.h
+++ b/drivers/media/video/em28xx/em28xx.h
@@ -596,6 +596,10 @@ struct em28xx {
         struct delayed_work sbutton_query_work;
 
         struct em28xx_dvb *dvb;
+
+        /* I2C keyboard data */
+        struct i2c_board_info info;
+        struct IR_i2c_init_data init_data;
 };
 
 struct em28xx_ops {