mfd: cros_ec: Use fixed size arrays to transfer data with the EC
The struct cros_ec_command will be used as an ioctl() argument for the
API to control the ChromeOS EC from user-space. So the data structure
has to be 64-bit safe to make it compatible between 32 and 64 avoiding
the need for a compat ioctl interface. Since pointers are self-aligned
to different byte boundaries, use fixed size arrays instead of pointers
for transferring ingoing and outgoing data with the Embedded Controller.
Also, re-arrange struct members by decreasing alignment requirements to
reduce the needing padding size.
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
index 875c22a..fa8dedd 100644
--- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c
+++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c
@@ -182,72 +182,41 @@
const u16 bus_num = bus->remote_bus;
int request_len;
int response_len;
- u8 *request = NULL;
- u8 *response = NULL;
int result;
- struct cros_ec_command msg;
+ struct cros_ec_command msg = { };
request_len = ec_i2c_count_message(i2c_msgs, num);
if (request_len < 0) {
dev_warn(dev, "Error constructing message %d\n", request_len);
- result = request_len;
- goto exit;
+ return request_len;
}
+
response_len = ec_i2c_count_response(i2c_msgs, num);
if (response_len < 0) {
/* Unexpected; no errors should come when NULL response */
dev_warn(dev, "Error preparing response %d\n", response_len);
- result = response_len;
- goto exit;
+ return response_len;
}
- if (request_len <= ARRAY_SIZE(bus->request_buf)) {
- request = bus->request_buf;
- } else {
- request = kzalloc(request_len, GFP_KERNEL);
- if (request == NULL) {
- result = -ENOMEM;
- goto exit;
- }
- }
- if (response_len <= ARRAY_SIZE(bus->response_buf)) {
- response = bus->response_buf;
- } else {
- response = kzalloc(response_len, GFP_KERNEL);
- if (response == NULL) {
- result = -ENOMEM;
- goto exit;
- }
- }
-
- result = ec_i2c_construct_message(request, i2c_msgs, num, bus_num);
+ result = ec_i2c_construct_message(msg.outdata, i2c_msgs, num, bus_num);
if (result)
- goto exit;
+ return result;
msg.version = 0;
msg.command = EC_CMD_I2C_PASSTHRU;
- msg.outdata = request;
msg.outsize = request_len;
- msg.indata = response;
msg.insize = response_len;
result = cros_ec_cmd_xfer(bus->ec, &msg);
if (result < 0)
- goto exit;
+ return result;
- result = ec_i2c_parse_response(response, i2c_msgs, &num);
+ result = ec_i2c_parse_response(msg.indata, i2c_msgs, &num);
if (result < 0)
- goto exit;
+ return result;
/* Indicate success by saying how many messages were sent */
- result = num;
-exit:
- if (request != bus->request_buf)
- kfree(request);
- if (response != bus->response_buf)
- kfree(response);
-
- return result;
+ return num;
}
static u32 ec_i2c_functionality(struct i2c_adapter *adap)