From 1b84f2a4cd4a6f517a313261f6f7c8caae5696c6 Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Mon, 2 Feb 2015 12:26:22 +0100 Subject: [PATCH] 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 Acked-by: Lee Jones Tested-by: Gwendal Grignou Reviewed-by: Gwendal Grignou Signed-off-by: Olof Johansson --- drivers/i2c/busses/i2c-cros-ec-tunnel.c | 51 +++++-------------------- drivers/input/keyboard/cros_ec_keyb.c | 13 ++++--- drivers/mfd/cros_ec.c | 15 ++++---- include/linux/mfd/cros_ec.h | 8 ++-- 4 files changed, 29 insertions(+), 58 deletions(-) diff --git a/drivers/i2c/busses/i2c-cros-ec-tunnel.c b/drivers/i2c/busses/i2c-cros-ec-tunnel.c index 875c22ae5400..fa8dedd8c3a2 100644 --- a/drivers/i2c/busses/i2c-cros-ec-tunnel.c +++ b/drivers/i2c/busses/i2c-cros-ec-tunnel.c @@ -182,72 +182,41 @@ static int ec_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg i2c_msgs[], 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; - } - - 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; - } + return response_len; } - 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) diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c index ffa989f2c785..769f8f7f62b7 100644 --- a/drivers/input/keyboard/cros_ec_keyb.c +++ b/drivers/input/keyboard/cros_ec_keyb.c @@ -148,16 +148,19 @@ static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev, static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state) { + int ret; struct cros_ec_command msg = { - .version = 0, .command = EC_CMD_MKBP_STATE, - .outdata = NULL, - .outsize = 0, - .indata = kb_state, .insize = ckdev->cols, }; - return cros_ec_cmd_xfer(ckdev->ec, &msg); + ret = cros_ec_cmd_xfer(ckdev->ec, &msg); + if (ret < 0) + return ret; + + memcpy(kb_state, msg.indata, ckdev->cols); + + return 0; } static irqreturn_t cros_ec_keyb_irq(int irq, void *data) diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c index fc0c81ef04ff..c872e1b0eaf8 100644 --- a/drivers/mfd/cros_ec.c +++ b/drivers/mfd/cros_ec.c @@ -74,15 +74,11 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, ret = ec_dev->cmd_xfer(ec_dev, msg); if (msg->result == EC_RES_IN_PROGRESS) { int i; - struct cros_ec_command status_msg; - struct ec_response_get_comms_status status; + struct cros_ec_command status_msg = { }; + struct ec_response_get_comms_status *status; - status_msg.version = 0; status_msg.command = EC_CMD_GET_COMMS_STATUS; - status_msg.outdata = NULL; - status_msg.outsize = 0; - status_msg.indata = (uint8_t *)&status; - status_msg.insize = sizeof(status); + status_msg.insize = sizeof(*status); /* * Query the EC's status until it's no longer busy or @@ -98,7 +94,10 @@ int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev, msg->result = status_msg.result; if (status_msg.result != EC_RES_SUCCESS) break; - if (!(status.flags & EC_COMMS_STATUS_PROCESSING)) + + status = (struct ec_response_get_comms_status *) + status_msg.indata; + if (!(status->flags & EC_COMMS_STATUS_PROCESSING)) break; } } diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h index 0e166b92f5b4..71675b14b5ca 100644 --- a/include/linux/mfd/cros_ec.h +++ b/include/linux/mfd/cros_ec.h @@ -38,20 +38,20 @@ enum { /* * @version: Command version number (often 0) * @command: Command to send (EC_CMD_...) - * @outdata: Outgoing data to EC * @outsize: Outgoing length in bytes - * @indata: Where to put the incoming data from EC * @insize: Max number of bytes to accept from EC * @result: EC's response to the command (separate from communication failure) + * @outdata: Outgoing data to EC + * @indata: Where to put the incoming data from EC */ struct cros_ec_command { uint32_t version; uint32_t command; - uint8_t *outdata; uint32_t outsize; - uint8_t *indata; uint32_t insize; uint32_t result; + uint8_t outdata[EC_PROTO2_MAX_PARAM_SIZE]; + uint8_t indata[EC_PROTO2_MAX_PARAM_SIZE]; }; /** -- 2.20.1