i2c-omap: Set latency requirements only once for several messages
authorSamu Onkalo <samu.p.onkalo@nokia.com>
Thu, 18 Nov 2010 10:04:20 +0000 (12:04 +0200)
committerBen Dooks <ben-linux@fluff.org>
Tue, 4 Jan 2011 01:16:53 +0000 (01:16 +0000)
Ordinary I2C read consist of two messages. First a write operation
to tell register address and then read operation to get data.
CPU wake up latency is set and removed twice in read case.
Set latency requirement before the message processing loop
and remove the requirement after the loop to remove latency
adjustment operations between the messages.

Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
drivers/i2c/busses/i2c-omap.c

index b33c78586bfccf815d9322df1d561b7bec5797b5..3e9323effc7ce3a9a51c53432aa5eb0c477c11c5 100644 (file)
@@ -616,12 +616,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
         * REVISIT: We should abort the transfer on signals, but the bus goes
         * into arbitration and we're currently unable to recover from it.
         */
-       if (dev->set_mpu_wkup_lat != NULL)
-               dev->set_mpu_wkup_lat(dev->dev, dev->latency);
        r = wait_for_completion_timeout(&dev->cmd_complete,
                                        OMAP_I2C_TIMEOUT);
-       if (dev->set_mpu_wkup_lat != NULL)
-               dev->set_mpu_wkup_lat(dev->dev, -1);
        dev->buf_len = 0;
        if (r < 0)
                return r;
@@ -672,12 +668,18 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
        if (r < 0)
                goto out;
 
+       if (dev->set_mpu_wkup_lat != NULL)
+               dev->set_mpu_wkup_lat(dev->dev, dev->latency);
+
        for (i = 0; i < num; i++) {
                r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
                if (r != 0)
                        break;
        }
 
+       if (dev->set_mpu_wkup_lat != NULL)
+               dev->set_mpu_wkup_lat(dev->dev, -1);
+
        if (r == 0)
                r = num;