[media] em28xx-input: i2c IR decoders: improve i2c_client handling

Instead of using a temporary stack allocated i2c_client in em28xx_i2c_ir_handle_key(),
allocate/free the i2c_client at module init/uninit and hook it into struct em28xx_IR
(if the device has an i2c IR decoder).
This reduces the frame size of function em28xx_i2c_ir_handle_key() and speeds
it up a bit.
Also make sure that all fields of struct i2c_client are initialized properly.

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/usb/em28xx/em28xx-input.c b/drivers/media/usb/em28xx/em28xx-input.c
index e978a2a..581f6da 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-input.c
+++ b/drivers/media/usb/em28xx/em28xx-input.c
@@ -71,8 +71,7 @@ struct em28xx_IR {
        unsigned int last_readcount;
        u64 rc_type;
 
-       /* i2c slave address of external device (if used) */
-       u16 i2c_dev_addr;
+       struct i2c_client *i2c_client;
 
        int  (*get_key_i2c)(struct i2c_client *ir, enum rc_type *protocol, u32 *scancode);
        int  (*get_key)(struct em28xx_IR *, struct em28xx_ir_poll_result *);
@@ -294,16 +293,11 @@ static int em2874_polling_getkey(struct em28xx_IR *ir,
 
 static int em28xx_i2c_ir_handle_key(struct em28xx_IR *ir)
 {
-       struct em28xx *dev = ir->dev;
        static u32 scancode;
        enum rc_type protocol;
        int rc;
-       struct i2c_client client;
-
-       client.adapter = &ir->dev->i2c_adap[dev->def_i2c_bus];
-       client.addr = ir->i2c_dev_addr;
 
-       rc = ir->get_key_i2c(&client, &protocol, &scancode);
+       rc = ir->get_key_i2c(ir->i2c_client, &protocol, &scancode);
        if (rc < 0) {
                dprintk("ir->get_key_i2c() failed: %d\n", rc);
                return rc;
@@ -361,7 +355,7 @@ static void em28xx_ir_work(struct work_struct *work)
 {
        struct em28xx_IR *ir = container_of(work, struct em28xx_IR, work.work);
 
-       if (ir->i2c_dev_addr) /* external i2c device */
+       if (ir->i2c_client) /* external i2c device */
                em28xx_i2c_ir_handle_key(ir);
        else /* internal device */
                em28xx_ir_handle_key(ir);
@@ -756,7 +750,13 @@ static int em28xx_ir_init(struct em28xx *dev)
                        goto error;
                }
 
-               ir->i2c_dev_addr = i2c_rc_dev_addr;
+               ir->i2c_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
+               if (!ir->i2c_client)
+                       goto error;
+               ir->i2c_client->adapter = &ir->dev->i2c_adap[dev->def_i2c_bus];
+               ir->i2c_client->addr = i2c_rc_dev_addr;
+               ir->i2c_client->flags = 0;
+               /* NOTE: all other fields of i2c_client are unused */
        } else {        /* internal device */
                switch (dev->chip_id) {
                case CHIP_ID_EM2860:
@@ -815,6 +815,7 @@ static int em28xx_ir_init(struct em28xx *dev)
        return 0;
 
 error:
+       kfree(ir->i2c_client);
        dev->ir = NULL;
        rc_free_device(rc);
        kfree(ir);
@@ -841,6 +842,8 @@ static int em28xx_ir_fini(struct em28xx *dev)
        if (ir->rc)
                rc_unregister_device(ir->rc);
 
+       kfree(ir->i2c_client);
+
        /* done */
        kfree(ir);
        dev->ir = NULL;