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-rw-r--r--Documentation/ABI/testing/debugfs-wilco-ec32
-rw-r--r--drivers/platform/chrome/wilco_ec/debugfs.c42
-rw-r--r--drivers/platform/chrome/wilco_ec/mailbox.c53
-rw-r--r--drivers/rtc/rtc-wilco-ec.c63
-rw-r--r--include/linux/platform_data/wilco-ec.h22
5 files changed, 91 insertions, 121 deletions
diff --git a/Documentation/ABI/testing/debugfs-wilco-ec b/Documentation/ABI/testing/debugfs-wilco-ec
index f814f112e213..7ff6b45be703 100644
--- a/Documentation/ABI/testing/debugfs-wilco-ec
+++ b/Documentation/ABI/testing/debugfs-wilco-ec
@@ -4,20 +4,30 @@ KernelVersion: 5.1
Description:
Write and read raw mailbox commands to the EC.
- For writing:
- Bytes 0-1 indicate the message type:
- 00 F0 = Execute Legacy Command
- 00 F2 = Read/Write NVRAM Property
- Byte 2 provides the command code
- Bytes 3+ consist of the data passed in the request
+ You can write a hexadecimal sentence to raw, and that series of
+ bytes will be sent to the EC. Then, you can read the bytes of
+ response by reading from raw.
- At least three bytes are required, for the msg type and command,
- with additional bytes optional for additional data.
+ For writing, bytes 0-1 indicate the message type, one of enum
+ wilco_ec_msg_type. Byte 2+ consist of the data passed in the
+ request, starting at MBOX[0]
+
+ At least three bytes are required for writing, two for the type
+ and at least a single byte of data. Only the first
+ EC_MAILBOX_DATA_SIZE bytes of MBOX will be used.
Example:
// Request EC info type 3 (EC firmware build date)
- $ echo 00 f0 38 00 03 00 > raw
+ // Corresponds with sending type 0x00f0 with
+ // MBOX = [38, 00, 03, 00]
+ $ echo 00 f0 38 00 03 00 > /sys/kernel/debug/wilco_ec/raw
// View the result. The decoded ASCII result "12/21/18" is
// included after the raw hex.
- $ cat raw
- 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 .12/21/18.8...
+ // Corresponds with MBOX = [00, 00, 31, 32, 2f, 32, 31, 38, ...]
+ $ cat /sys/kernel/debug/wilco_ec/raw
+ 00 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 ..12/21/18.8...
+
+ Note that the first 32 bytes of the received MBOX[] will be
+ printed, even if some of the data is junk. It is up to you to
+ know how many of the first bytes of data are the actual
+ response.
diff --git a/drivers/platform/chrome/wilco_ec/debugfs.c b/drivers/platform/chrome/wilco_ec/debugfs.c
index c090db2cd5be..8d307378c1cb 100644
--- a/drivers/platform/chrome/wilco_ec/debugfs.c
+++ b/drivers/platform/chrome/wilco_ec/debugfs.c
@@ -4,31 +4,7 @@
*
* Copyright 2019 Google LLC
*
- * There is only one attribute used for debugging, called raw.
- * You can write a hexadecimal sentence to raw, and that series of bytes
- * will be sent to the EC. Then, you can read the bytes of response
- * by reading from raw.
- *
- * For writing:
- * Bytes 0-1 indicate the message type:
- * 00 F0 = Execute Legacy Command
- * 00 F2 = Read/Write NVRAM Property
- * Byte 2 provides the command code
- * Bytes 3+ consist of the data passed in the request
- *
- * When referencing the EC interface spec, byte 2 corresponds to MBOX[0],
- * byte 3 corresponds to MBOX[1], etc.
- *
- * At least three bytes are required, for the msg type and command,
- * with additional bytes optional for additional data.
- *
- * Example:
- * // Request EC info type 3 (EC firmware build date)
- * $ echo 00 f0 38 00 03 00 > raw
- * // View the result. The decoded ASCII result "12/21/18" is
- * // included after the raw hex.
- * $ cat raw
- * 00 31 32 2f 32 31 2f 31 38 00 38 00 01 00 2f 00 .12/21/18.8...
+ * See Documentation/ABI/testing/debugfs-wilco-ec for usage.
*/
#include <linux/ctype.h>
@@ -136,18 +112,15 @@ static ssize_t raw_write(struct file *file, const char __user *user_buf,
ret = parse_hex_sentence(buf, kcount, request_data, TYPE_AND_DATA_SIZE);
if (ret < 0)
return ret;
- /* Need at least two bytes for message type and one for command */
+ /* Need at least two bytes for message type and one byte of data */
if (ret < 3)
return -EINVAL;
- /* Clear response data buffer */
- memset(debug_info->raw_data, '\0', EC_MAILBOX_DATA_SIZE_EXTENDED);
-
msg.type = request_data[0] << 8 | request_data[1];
- msg.flags = WILCO_EC_FLAG_RAW;
- msg.command = request_data[2];
- msg.request_data = ret > 3 ? request_data + 3 : 0;
- msg.request_size = ret - 3;
+ msg.flags = 0;
+ msg.request_data = request_data + 2;
+ msg.request_size = ret - 2;
+ memset(debug_info->raw_data, 0, sizeof(debug_info->raw_data));
msg.response_data = debug_info->raw_data;
msg.response_size = EC_MAILBOX_DATA_SIZE;
@@ -174,7 +147,8 @@ static ssize_t raw_read(struct file *file, char __user *user_buf, size_t count,
fmt_len = hex_dump_to_buffer(debug_info->raw_data,
debug_info->response_size,
16, 1, debug_info->formatted_data,
- FORMATTED_BUFFER_SIZE, true);
+ sizeof(debug_info->formatted_data),
+ true);
/* Only return response the first time it is read */
debug_info->response_size = 0;
}
diff --git a/drivers/platform/chrome/wilco_ec/mailbox.c b/drivers/platform/chrome/wilco_ec/mailbox.c
index 14355668ddfa..7fb58b487963 100644
--- a/drivers/platform/chrome/wilco_ec/mailbox.c
+++ b/drivers/platform/chrome/wilco_ec/mailbox.c
@@ -92,21 +92,10 @@ static void wilco_ec_prepare(struct wilco_ec_message *msg,
struct wilco_ec_request *rq)
{
memset(rq, 0, sizeof(*rq));
-
- /* Handle messages without trimming bytes from the request */
- if (msg->request_size && msg->flags & WILCO_EC_FLAG_RAW_REQUEST) {
- rq->reserved_raw = *(u8 *)msg->request_data;
- msg->request_size--;
- memmove(msg->request_data, msg->request_data + 1,
- msg->request_size);
- }
-
- /* Fill in request packet */
rq->struct_version = EC_MAILBOX_PROTO_VERSION;
rq->mailbox_id = msg->type;
rq->mailbox_version = EC_MAILBOX_VERSION;
- rq->data_size = msg->request_size + EC_MAILBOX_DATA_EXTRA;
- rq->command = msg->command;
+ rq->data_size = msg->request_size;
/* Checksum header and data */
rq->checksum = wilco_ec_checksum(rq, sizeof(*rq));
@@ -159,6 +148,12 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec,
return -EIO;
}
+ /*
+ * The EC always returns either EC_MAILBOX_DATA_SIZE or
+ * EC_MAILBOX_DATA_SIZE_EXTENDED bytes of data, so we need to
+ * calculate the checksum on **all** of this data, even if we
+ * won't use all of it.
+ */
if (msg->flags & WILCO_EC_FLAG_EXTENDED_DATA)
size = EC_MAILBOX_DATA_SIZE_EXTENDED;
else
@@ -173,33 +168,26 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec,
return -EBADMSG;
}
- /* Check that the EC reported success */
- msg->result = rs->result;
- if (msg->result) {
- dev_dbg(ec->dev, "bad response: 0x%02x\n", msg->result);
+ if (rs->result) {
+ dev_dbg(ec->dev, "EC reported failure: 0x%02x\n", rs->result);
return -EBADMSG;
}
- /* Check the returned data size, skipping the header */
if (rs->data_size != size) {
dev_dbg(ec->dev, "unexpected packet size (%u != %zu)",
rs->data_size, size);
return -EMSGSIZE;
}
- /* Skip 1 response data byte unless specified */
- size = (msg->flags & WILCO_EC_FLAG_RAW_RESPONSE) ? 0 : 1;
- if ((ssize_t) rs->data_size - size < msg->response_size) {
- dev_dbg(ec->dev, "response data too short (%zd < %zu)",
- (ssize_t) rs->data_size - size, msg->response_size);
+ if (rs->data_size < msg->response_size) {
+ dev_dbg(ec->dev, "EC didn't return enough data (%u < %zu)",
+ rs->data_size, msg->response_size);
return -EMSGSIZE;
}
- /* Ignore response data bytes as requested */
- memcpy(msg->response_data, rs->data + size, msg->response_size);
+ memcpy(msg->response_data, rs->data, msg->response_size);
- /* Return actual amount of data received */
- return msg->response_size;
+ return rs->data_size;
}
/**
@@ -207,10 +195,12 @@ static int wilco_ec_transfer(struct wilco_ec_device *ec,
* @ec: EC device.
* @msg: EC message data for request and response.
*
- * On entry msg->type, msg->flags, msg->command, msg->request_size,
- * msg->response_size, and msg->request_data should all be filled in.
+ * On entry msg->type, msg->request_size, and msg->request_data should all be
+ * filled in. If desired, msg->flags can be set.
*
- * On exit msg->result and msg->response_data will be filled.
+ * If a response is expected, msg->response_size should be set, and
+ * msg->response_data should point to a buffer with enough space. On exit
+ * msg->response_data will be filled.
*
* Return: number of bytes received or negative error code on failure.
*/
@@ -219,9 +209,8 @@ int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg)
struct wilco_ec_request *rq;
int ret;
- dev_dbg(ec->dev, "cmd=%02x type=%04x flags=%02x rslen=%zu rqlen=%zu\n",
- msg->command, msg->type, msg->flags, msg->response_size,
- msg->request_size);
+ dev_dbg(ec->dev, "type=%04x flags=%02x rslen=%zu rqlen=%zu\n",
+ msg->type, msg->flags, msg->response_size, msg->request_size);
mutex_lock(&ec->mailbox_lock);
/* Prepare request packet */
diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c
index e62bda0cb53e..8ad4c4e6d557 100644
--- a/drivers/rtc/rtc-wilco-ec.c
+++ b/drivers/rtc/rtc-wilco-ec.c
@@ -21,8 +21,20 @@
#define EC_CMOS_TOD_WRITE 0x02
#define EC_CMOS_TOD_READ 0x08
+/* Message sent to the EC to request the current time. */
+struct ec_rtc_read_request {
+ u8 command;
+ u8 reserved;
+ u8 param;
+} __packed;
+static struct ec_rtc_read_request read_rq = {
+ .command = EC_COMMAND_CMOS,
+ .param = EC_CMOS_TOD_READ,
+};
+
/**
- * struct ec_rtc_read - Format of RTC returned by EC.
+ * struct ec_rtc_read_response - Format of RTC returned by EC.
+ * @reserved: Unused byte
* @second: Second value (0..59)
* @minute: Minute value (0..59)
* @hour: Hour value (0..23)
@@ -33,7 +45,8 @@
*
* All values are presented in binary (not BCD).
*/
-struct ec_rtc_read {
+struct ec_rtc_read_response {
+ u8 reserved;
u8 second;
u8 minute;
u8 hour;
@@ -44,8 +57,10 @@ struct ec_rtc_read {
} __packed;
/**
- * struct ec_rtc_write - Format of RTC sent to the EC.
- * @param: EC_CMOS_TOD_WRITE
+ * struct ec_rtc_write_request - Format of RTC sent to the EC.
+ * @command: Always EC_COMMAND_CMOS
+ * @reserved: Unused byte
+ * @param: Always EC_CMOS_TOD_WRITE
* @century: Century value (full year / 100)
* @year: Year value (full year % 100)
* @month: Month value (1..12)
@@ -57,7 +72,9 @@ struct ec_rtc_read {
*
* All values are presented in BCD.
*/
-struct ec_rtc_write {
+struct ec_rtc_write_request {
+ u8 command;
+ u8 reserved;
u8 param;
u8 century;
u8 year;
@@ -72,19 +89,17 @@ struct ec_rtc_write {
static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
{
struct wilco_ec_device *ec = dev_get_drvdata(dev->parent);
- u8 param = EC_CMOS_TOD_READ;
- struct ec_rtc_read rtc;
- struct wilco_ec_message msg = {
- .type = WILCO_EC_MSG_LEGACY,
- .flags = WILCO_EC_FLAG_RAW_RESPONSE,
- .command = EC_COMMAND_CMOS,
- .request_data = &param,
- .request_size = sizeof(param),
- .response_data = &rtc,
- .response_size = sizeof(rtc),
- };
+ struct ec_rtc_read_response rtc;
+ struct wilco_ec_message msg;
int ret;
+ memset(&msg, 0, sizeof(msg));
+ msg.type = WILCO_EC_MSG_LEGACY;
+ msg.request_data = &read_rq;
+ msg.request_size = sizeof(read_rq);
+ msg.response_data = &rtc;
+ msg.response_size = sizeof(rtc);
+
ret = wilco_ec_mailbox(ec, &msg);
if (ret < 0)
return ret;
@@ -106,14 +121,8 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm)
static int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm)
{
struct wilco_ec_device *ec = dev_get_drvdata(dev->parent);
- struct ec_rtc_write rtc;
- struct wilco_ec_message msg = {
- .type = WILCO_EC_MSG_LEGACY,
- .flags = WILCO_EC_FLAG_RAW_RESPONSE,
- .command = EC_COMMAND_CMOS,
- .request_data = &rtc,
- .request_size = sizeof(rtc),
- };
+ struct ec_rtc_write_request rtc;
+ struct wilco_ec_message msg;
int year = tm->tm_year + 1900;
/*
* Convert from 0=Sunday to 0=Saturday for the EC
@@ -123,6 +132,7 @@ static int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm)
int wday = tm->tm_wday == 6 ? 0 : tm->tm_wday + 1;
int ret;
+ rtc.command = EC_COMMAND_CMOS;
rtc.param = EC_CMOS_TOD_WRITE;
rtc.century = bin2bcd(year / 100);
rtc.year = bin2bcd(year % 100);
@@ -133,6 +143,11 @@ static int wilco_ec_rtc_write(struct device *dev, struct rtc_time *tm)
rtc.second = bin2bcd(tm->tm_sec);
rtc.weekday = bin2bcd(wday);
+ memset(&msg, 0, sizeof(msg));
+ msg.type = WILCO_EC_MSG_LEGACY;
+ msg.request_data = &rtc;
+ msg.request_size = sizeof(rtc);
+
ret = wilco_ec_mailbox(ec, &msg);
if (ret < 0)
return ret;
diff --git a/include/linux/platform_data/wilco-ec.h b/include/linux/platform_data/wilco-ec.h
index 446473a46b88..1ff224793c99 100644
--- a/include/linux/platform_data/wilco-ec.h
+++ b/include/linux/platform_data/wilco-ec.h
@@ -14,10 +14,6 @@
/* Message flags for using the mailbox() interface */
#define WILCO_EC_FLAG_NO_RESPONSE BIT(0) /* EC does not respond */
#define WILCO_EC_FLAG_EXTENDED_DATA BIT(1) /* EC returns 256 data bytes */
-#define WILCO_EC_FLAG_RAW_REQUEST BIT(2) /* Do not trim request data */
-#define WILCO_EC_FLAG_RAW_RESPONSE BIT(3) /* Do not trim response data */
-#define WILCO_EC_FLAG_RAW (WILCO_EC_FLAG_RAW_REQUEST | \
- WILCO_EC_FLAG_RAW_RESPONSE)
/* Normal commands have a maximum 32 bytes of data */
#define EC_MAILBOX_DATA_SIZE 32
@@ -56,10 +52,7 @@ struct wilco_ec_device {
* @mailbox_id: Mailbox identifier, specifies the command set.
* @mailbox_version: Mailbox interface version %EC_MAILBOX_VERSION
* @reserved: Set to zero.
- * @data_size: Length of request, data + last 2 bytes of the header.
- * @command: Mailbox command code, unique for each mailbox_id set.
- * @reserved_raw: Set to zero for most commands, but is used by
- * some command types and for raw commands.
+ * @data_size: Length of following data.
*/
struct wilco_ec_request {
u8 struct_version;
@@ -68,8 +61,6 @@ struct wilco_ec_request {
u8 mailbox_version;
u8 reserved;
u16 data_size;
- u8 command;
- u8 reserved_raw;
} __packed;
/**
@@ -79,8 +70,6 @@ struct wilco_ec_request {
* @result: Result code from the EC. Non-zero indicates an error.
* @data_size: Length of the response data buffer.
* @reserved: Set to zero.
- * @mbox0: EC returned data at offset 0 is unused (always 0) so this byte
- * is treated as part of the header instead of the data.
* @data: Response data buffer. Max size is %EC_MAILBOX_DATA_SIZE_EXTENDED.
*/
struct wilco_ec_response {
@@ -89,7 +78,6 @@ struct wilco_ec_response {
u16 result;
u16 data_size;
u8 reserved[2];
- u8 mbox0;
u8 data[0];
} __packed;
@@ -111,21 +99,15 @@ enum wilco_ec_msg_type {
* struct wilco_ec_message - Request and response message.
* @type: Mailbox message type.
* @flags: Message flags, e.g. %WILCO_EC_FLAG_NO_RESPONSE.
- * @command: Mailbox command code.
- * @result: Result code from the EC. Non-zero indicates an error.
* @request_size: Number of bytes to send to the EC.
* @request_data: Buffer containing the request data.
- * @response_size: Number of bytes expected from the EC.
- * This is 32 by default and 256 if the flag
- * is set for %WILCO_EC_FLAG_EXTENDED_DATA
+ * @response_size: Number of bytes to read from EC.
* @response_data: Buffer containing the response data, should be
* response_size bytes and allocated by caller.
*/
struct wilco_ec_message {
enum wilco_ec_msg_type type;
u8 flags;
- u8 command;
- u8 result;
size_t request_size;
void *request_data;
size_t response_size;
generated by cgit (git 2.34.1) at 2024-05-04 10:35:14 +0000