From a841178445bb72a3d566b4e6ab9d19e9b002eb47 Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Tue, 9 Jun 2015 13:04:42 +0200 Subject: mfd: cros_ec: Use a zero-length array for command data Commit 1b84f2a4cd4a ("mfd: cros_ec: Use fixed size arrays to transfer data with the EC") modified the struct cros_ec_command fields to not use pointers for the input and output buffers and use fixed length arrays instead. This change was made because the cros_ec ioctl API uses that struct cros_ec_command to allow user-space to send commands to the EC and to get data from the EC. So using pointers made the API not 64-bit safe. Unfortunately this approach was not flexible enough for all the use-cases since there may be a need to send larger commands on newer versions of the EC command protocol. So to avoid to choose a constant length that it may be too big for most commands and thus wasting memory and CPU cycles on copy from and to user-space or having a size that is too small for some big commands, use a zero-length array that is both 64-bit safe and flexible. The same buffer is used for both output and input data so the maximum of these values should be used to allocate it. Suggested-by: Gwendal Grignou Signed-off-by: Javier Martinez Canillas Tested-by: Heiko Stuebner Acked-by: Lee Jones Acked-by: Olof Johansson Signed-off-by: Lee Jones --- drivers/mfd/cros_ec_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/mfd/cros_ec_spi.c') diff --git a/drivers/mfd/cros_ec_spi.c b/drivers/mfd/cros_ec_spi.c index 27bd52e5e8b7..573730fec947 100644 --- a/drivers/mfd/cros_ec_spi.c +++ b/drivers/mfd/cros_ec_spi.c @@ -299,7 +299,7 @@ static int cros_ec_cmd_xfer_spi(struct cros_ec_device *ec_dev, for (i = 0; i < len; i++) { sum += ptr[i + 2]; if (ec_msg->insize) - ec_msg->indata[i] = ptr[i + 2]; + ec_msg->data[i] = ptr[i + 2]; } sum &= 0xff; -- cgit v1.2.1