cros_ec: i2c: Group i2c write / read into single transaction
authorMoritz Fischer <moritz.fischer@ettus.com>
Thu, 12 Jan 2017 17:47:30 +0000 (09:47 -0800)
committerSimon Glass <sjg@chromium.org>
Wed, 8 Feb 2017 13:07:13 +0000 (06:07 -0700)
Replace dm_i2c_write() / dm_i2c_read() with transaction using
struct i2c_msg[2] in order to allow for i2c controller to detect
write/read cycle to emit a repeated start condition.

Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: u-boot@lists.denx.de
Acked-by: Simon Glass <sjg@chromium.org>
Tested on snow:
Tested-by: Simon Glass <sjg@chromium.org>
drivers/misc/cros_ec_i2c.c

index 3de18b2d2ade9e1a18e6e650358fa55747c425f3..f2f6961499bc2ddb0f52cab1ce0cc8d5b3054e1b 100644 (file)
@@ -29,6 +29,8 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd,
                               int dout_len, uint8_t **dinp, int din_len)
 {
        struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
+       struct dm_i2c_chip *chip = dev_get_parent_platdata(udev);
+       struct i2c_msg i2c_msg[2];
        /* version8, cmd8, arglen8, out8[dout_len], csum8 */
        int out_bytes = dout_len + 4;
        /* response8, arglen8, in8[din_len], checksum8 */
@@ -53,6 +55,11 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd,
        assert(dout_len >= 0);
        assert(dinp);
 
+       i2c_msg[0].addr = chip->chip_addr;
+       i2c_msg[0].len = out_bytes;
+       i2c_msg[0].buf = dev->dout;
+       i2c_msg[0].flags = 0;
+
        /*
         * Copy command and data into output buffer so we can do a single I2C
         * burst transaction.
@@ -85,24 +92,21 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd,
        *ptr++ = (uint8_t)
                cros_ec_calc_checksum(dev->dout, dout_len + 3);
 
+       i2c_msg[1].addr = chip->chip_addr;
+       i2c_msg[1].len = in_bytes;
+       i2c_msg[1].buf = in_ptr;
+       i2c_msg[1].flags = I2C_M_RD;
+
        /* Send output data */
        cros_ec_dump_data("out", -1, dev->dout, out_bytes);
-       ret = dm_i2c_write(udev, 0, dev->dout, out_bytes);
+
+       ret = dm_i2c_xfer(udev, &i2c_msg[0], 2);
        if (ret) {
-               debug("%s: Cannot complete I2C write to %s\n", __func__,
+               debug("%s: Could not execute transfer to %s\n", __func__,
                      udev->name);
                ret = -1;
        }
 
-       if (!ret) {
-               ret = dm_i2c_read(udev, 0, in_ptr, in_bytes);
-               if (ret) {
-                       debug("%s: Cannot complete I2C read from %s\n",
-                             __func__, udev->name);
-                       ret = -1;
-               }
-       }
-
        if (*in_ptr != EC_RES_SUCCESS) {
                debug("%s: Received bad result code %d\n", __func__, *in_ptr);
                return -(int)*in_ptr;