mfd: cros_ec: add proto v3 skeleton

Add support in cros_ec.c to handle EC host command protocol v3.
For v3+, probe for maximum shared protocol version and max
request, response, and passthrough sizes. For now, this will
always fall back to v2, since there is no bus-specific code
for handling proto v3 packets.

Signed-off-by: Stephen Barber <[email protected]>
Signed-off-by: Javier Martinez Canillas <[email protected]>
Reviewed-by: Gwendal Grignou <[email protected]>
Tested-by: Gwendal Grignou <[email protected]>
Tested-by: Heiko Stuebner <[email protected]>
Acked-by: Lee Jones <[email protected]>
Acked-by: Olof Johansson <[email protected]>
Signed-off-by: Lee Jones <[email protected]>

Author: Stephen Barber

drivers/mfd/cros_ec.c

@@ -36,19 +36,22 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 	struct device *dev = ec_dev->dev;
 	int err = 0;
 
-	if (ec_dev->din_size) {
-		ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
-		if (!ec_dev->din)
-			return -ENOMEM;
-	}
-	if (ec_dev->dout_size) {
-		ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
-		if (!ec_dev->dout)
-			return -ENOMEM;
-	}
+	ec_dev->max_request = sizeof(struct ec_params_hello);
+	ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
+	ec_dev->max_passthru = 0;
+
+	ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
+	if (!ec_dev->din)
+		return -ENOMEM;
+
+	ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
+	if (!ec_dev->dout)
+		return -ENOMEM;
 
 	mutex_init(&ec_dev->lock);
 
+	cros_ec_query_all(ec_dev);
+
 	err = mfd_add_devices(dev, 0, cros_devs,
 			      ARRAY_SIZE(cros_devs),
 			      NULL, ec_dev->irq, NULL);

drivers/mfd/cros_ec_i2c.c

@@ -143,8 +143,12 @@ static int cros_ec_i2c_probe(struct i2c_client *client,
 	ec_dev->priv = client;
 	ec_dev->irq = client->irq;
 	ec_dev->cmd_xfer = cros_ec_cmd_xfer_i2c;
+	ec_dev->pkt_xfer = NULL;
 	ec_dev->ec_name = client->name;
 	ec_dev->phys_name = client->adapter->name;
+	ec_dev->din_size = sizeof(struct ec_host_response) +
+			   sizeof(struct ec_response_get_protocol_info);
+	ec_dev->dout_size = sizeof(struct ec_host_request);
 
 	err = cros_ec_register(ec_dev);
 	if (err) {

drivers/mfd/cros_ec_spi.c

@@ -361,10 +361,13 @@ static int cros_ec_spi_probe(struct spi_device *spi)
 	ec_dev->priv = ec_spi;
 	ec_dev->irq = spi->irq;
 	ec_dev->cmd_xfer = cros_ec_cmd_xfer_spi;
+	ec_dev->pkt_xfer = NULL;
 	ec_dev->ec_name = ec_spi->spi->modalias;
 	ec_dev->phys_name = dev_name(&ec_spi->spi->dev);
-	ec_dev->din_size = EC_MSG_BYTES + EC_MSG_PREAMBLE_COUNT;
-	ec_dev->dout_size = EC_MSG_BYTES;
+	ec_dev->din_size = EC_MSG_PREAMBLE_COUNT +
+			   sizeof(struct ec_host_response) +
+			   sizeof(struct ec_response_get_protocol_info);
+	ec_dev->dout_size = sizeof(struct ec_host_request);
 
 	err = cros_ec_register(ec_dev);
 	if (err) {

drivers/platform/chrome/cros_ec_lpc.c

@@ -215,7 +215,11 @@ static int cros_ec_lpc_probe(struct platform_device *pdev)
 	ec_dev->ec_name = pdev->name;
 	ec_dev->phys_name = dev_name(dev);
 	ec_dev->cmd_xfer = cros_ec_cmd_xfer_lpc;
+	ec_dev->pkt_xfer = NULL;
 	ec_dev->cmd_readmem = cros_ec_lpc_readmem;
+	ec_dev->din_size = sizeof(struct ec_host_response) +
+			   sizeof(struct ec_response_get_protocol_info);
+	ec_dev->dout_size = sizeof(struct ec_host_request);
 
 	ret = cros_ec_register(ec_dev);
 	if (ret) {