i2c: omap: use core to detect 'no zero length' quirk

And don't reimplement in the driver.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

drivers/i2c/busses/i2c-omap.c

@@ -661,9 +661,6 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
 		msg->addr, msg->len, msg->flags, stop);
 
-	if (msg->len == 0)
-		return -EINVAL;
-
 	omap->receiver = !!(msg->flags & I2C_M_RD);
 	omap_i2c_resize_fifo(omap, msg->len, omap->receiver);
 
@@ -1179,6 +1176,10 @@ static const struct i2c_algorithm omap_i2c_algo = {
 	.functionality	= omap_i2c_func,
 };
 
+static const struct i2c_adapter_quirks omap_i2c_quirks = {
+	.flags = I2C_AQ_NO_ZERO_LEN,
+};
+
 #ifdef CONFIG_OF
 static struct omap_i2c_bus_platform_data omap2420_pdata = {
 	.rev = OMAP_I2C_IP_VERSION_1,
@@ -1453,6 +1454,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	adap->class = I2C_CLASS_DEPRECATED;
 	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
 	adap->algo = &omap_i2c_algo;
+	adap->quirks = &omap_i2c_quirks;
 	adap->dev.parent = &pdev->dev;
 	adap->dev.of_node = pdev->dev.of_node;
 	adap->bus_recovery_info = &omap_i2c_bus_recovery_info;