summaryrefslogtreecommitdiff
path: root/drivers/mfd/cros_ec_i2c.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mfd/cros_ec_i2c.c')
-rw-r--r--drivers/mfd/cros_ec_i2c.c170
1 files changed, 165 insertions, 5 deletions
diff --git a/drivers/mfd/cros_ec_i2c.c b/drivers/mfd/cros_ec_i2c.c
index c0c30f4f946f..b9a0963ca5c3 100644
--- a/drivers/mfd/cros_ec_i2c.c
+++ b/drivers/mfd/cros_ec_i2c.c
@@ -13,6 +13,7 @@
* GNU General Public License for more details.
*/
+#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
@@ -22,6 +23,32 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
+/**
+ * Request format for protocol v3
+ * byte 0 0xda (EC_COMMAND_PROTOCOL_3)
+ * byte 1-8 struct ec_host_request
+ * byte 10- response data
+ */
+struct ec_host_request_i2c {
+ /* Always 0xda to backward compatible with v2 struct */
+ uint8_t command_protocol;
+ struct ec_host_request ec_request;
+} __packed;
+
+
+/*
+ * Response format for protocol v3
+ * byte 0 result code
+ * byte 1 packet_length
+ * byte 2-9 struct ec_host_response
+ * byte 10- response data
+ */
+struct ec_host_response_i2c {
+ uint8_t result;
+ uint8_t packet_length;
+ struct ec_host_response ec_response;
+} __packed;
+
static inline struct cros_ec_device *to_ec_dev(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
@@ -29,6 +56,134 @@ static inline struct cros_ec_device *to_ec_dev(struct device *dev)
return i2c_get_clientdata(client);
}
+static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *msg)
+{
+ struct i2c_client *client = ec_dev->priv;
+ int ret = -ENOMEM;
+ int i;
+ int packet_len;
+ u8 *out_buf = NULL;
+ u8 *in_buf = NULL;
+ u8 sum;
+ struct i2c_msg i2c_msg[2];
+ struct ec_host_response *ec_response;
+ struct ec_host_request_i2c *ec_request_i2c;
+ struct ec_host_response_i2c *ec_response_i2c;
+ int request_header_size = sizeof(struct ec_host_request_i2c);
+ int response_header_size = sizeof(struct ec_host_response_i2c);
+
+ i2c_msg[0].addr = client->addr;
+ i2c_msg[0].flags = 0;
+ i2c_msg[1].addr = client->addr;
+ i2c_msg[1].flags = I2C_M_RD;
+
+ packet_len = msg->insize + response_header_size;
+ BUG_ON(packet_len > ec_dev->din_size);
+ in_buf = ec_dev->din;
+ i2c_msg[1].len = packet_len;
+ i2c_msg[1].buf = (char *) in_buf;
+
+ packet_len = msg->outsize + request_header_size;
+ BUG_ON(packet_len > ec_dev->dout_size);
+ out_buf = ec_dev->dout;
+ i2c_msg[0].len = packet_len;
+ i2c_msg[0].buf = (char *) out_buf;
+
+ /* create request data */
+ ec_request_i2c = (struct ec_host_request_i2c *) out_buf;
+ ec_request_i2c->command_protocol = EC_COMMAND_PROTOCOL_3;
+
+ ec_dev->dout++;
+ ret = cros_ec_prepare_tx(ec_dev, msg);
+ ec_dev->dout--;
+
+ /* send command to EC and read answer */
+ ret = i2c_transfer(client->adapter, i2c_msg, 2);
+ if (ret < 0) {
+ dev_dbg(ec_dev->dev, "i2c transfer failed: %d\n", ret);
+ goto done;
+ } else if (ret != 2) {
+ dev_err(ec_dev->dev, "failed to get response: %d\n", ret);
+ ret = -EIO;
+ goto done;
+ }
+
+ ec_response_i2c = (struct ec_host_response_i2c *) in_buf;
+ msg->result = ec_response_i2c->result;
+ ec_response = &ec_response_i2c->ec_response;
+
+ switch (msg->result) {
+ case EC_RES_SUCCESS:
+ break;
+ case EC_RES_IN_PROGRESS:
+ ret = -EAGAIN;
+ dev_dbg(ec_dev->dev, "command 0x%02x in progress\n",
+ msg->command);
+ goto done;
+
+ default:
+ dev_dbg(ec_dev->dev, "command 0x%02x returned %d\n",
+ msg->command, msg->result);
+ /*
+ * When we send v3 request to v2 ec, ec won't recognize the
+ * 0xda (EC_COMMAND_PROTOCOL_3) and will return with status
+ * EC_RES_INVALID_COMMAND with zero data length.
+ *
+ * In case of invalid command for v3 protocol the data length
+ * will be at least sizeof(struct ec_host_response)
+ */
+ if (ec_response_i2c->result == EC_RES_INVALID_COMMAND &&
+ ec_response_i2c->packet_length == 0) {
+ ret = -EPROTONOSUPPORT;
+ goto done;
+ }
+ }
+
+ if (ec_response_i2c->packet_length < sizeof(struct ec_host_response)) {
+ dev_err(ec_dev->dev,
+ "response of %u bytes too short; not a full header\n",
+ ec_response_i2c->packet_length);
+ ret = -EBADMSG;
+ goto done;
+ }
+
+ if (msg->insize < ec_response->data_len) {
+ dev_err(ec_dev->dev,
+ "response data size is too large: expected %u, got %u\n",
+ msg->insize,
+ ec_response->data_len);
+ ret = -EMSGSIZE;
+ goto done;
+ }
+
+ /* copy response packet payload and compute checksum */
+ sum = 0;
+ for (i = 0; i < sizeof(struct ec_host_response); i++)
+ sum += ((u8 *)ec_response)[i];
+
+ memcpy(msg->data,
+ in_buf + response_header_size,
+ ec_response->data_len);
+ for (i = 0; i < ec_response->data_len; i++)
+ sum += msg->data[i];
+
+ /* All bytes should sum to zero */
+ if (sum) {
+ dev_err(ec_dev->dev, "bad packet checksum\n");
+ ret = -EBADMSG;
+ goto done;
+ }
+
+ ret = ec_response->data_len;
+
+done:
+ if (msg->command == EC_CMD_REBOOT_EC)
+ msleep(EC_REBOOT_DELAY_MS);
+
+ return ret;
+}
+
static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg)
{
@@ -76,7 +231,7 @@ static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
/* copy message payload and compute checksum */
sum = out_buf[0] + out_buf[1] + out_buf[2];
for (i = 0; i < msg->outsize; i++) {
- out_buf[3 + i] = msg->outdata[i];
+ out_buf[3 + i] = msg->data[i];
sum += out_buf[3 + i];
}
out_buf[3 + msg->outsize] = sum;
@@ -109,7 +264,7 @@ static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
/* copy response packet payload and compute checksum */
sum = in_buf[0] + in_buf[1];
for (i = 0; i < len; i++) {
- msg->indata[i] = in_buf[2 + i];
+ msg->data[i] = in_buf[2 + i];
sum += in_buf[2 + i];
}
dev_dbg(ec_dev->dev, "packet: %*ph, sum = %02x\n",
@@ -121,9 +276,12 @@ static int cros_ec_cmd_xfer_i2c(struct cros_ec_device *ec_dev,
}
ret = len;
- done:
+done:
kfree(in_buf);
kfree(out_buf);
+ if (msg->command == EC_CMD_REBOOT_EC)
+ msleep(EC_REBOOT_DELAY_MS);
+
return ret;
}
@@ -143,9 +301,11 @@ 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->ec_name = client->name;
+ ec_dev->pkt_xfer = cros_ec_pkt_xfer_i2c;
ec_dev->phys_name = client->adapter->name;
- ec_dev->parent = &client->dev;
+ ec_dev->din_size = sizeof(struct ec_host_response_i2c) +
+ sizeof(struct ec_response_get_protocol_info);
+ ec_dev->dout_size = sizeof(struct ec_host_request_i2c);
err = cros_ec_register(ec_dev);
if (err) {
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-14 10:21:36 +0000