[PATCH 07/13] platform/chrome: cros_ec_proto: separate fill_protocol_info()

From: Tzung-Bi Shih
Date: Mon Jun 06 2022 - 10:12:49 EST


Rename cros_ec_host_command_proto_query() to fill_protocol_info() and
make it responsible for setting `ec_dev` fields according to the
response protocol info.

Also make cros_ec_get_host_event_wake_mask() allocate its own message
buffer. It was lucky that size of `struct ec_response_host_event_mask`
is less than `struct ec_response_get_protocol_info`. Thus, the buffer
wasn't overflow.

Signed-off-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>
---
drivers/platform/chrome/cros_ec_proto.c | 130 +++++++++----------
drivers/platform/chrome/cros_ec_proto_test.c | 28 ++--
2 files changed, 76 insertions(+), 82 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 71ba6a56ad7c..f57b4dba95b7 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -242,47 +242,53 @@ EXPORT_SYMBOL(cros_ec_check_result);
* the caller has ec_dev->lock mutex, or the caller knows there is
* no other command in progress.
*/
-static int cros_ec_get_host_event_wake_mask(struct cros_ec_device *ec_dev,
- struct cros_ec_command *msg,
- uint32_t *mask)
+static int cros_ec_get_host_event_wake_mask(struct cros_ec_device *ec_dev, uint32_t *mask)
{
+ struct cros_ec_command *msg;
struct ec_response_host_event_mask *r;
int ret, mapped;

+ msg = kzalloc(sizeof(*msg) + sizeof(*r), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
msg->command = EC_CMD_HOST_EVENT_GET_WAKE_MASK;
- msg->version = 0;
- msg->outsize = 0;
msg->insize = sizeof(*r);

ret = send_command(ec_dev, msg);
if (ret >= 0) {
mapped = cros_ec_map_error(msg->result);
- if (mapped)
- return mapped;
+ if (mapped) {
+ ret = mapped;
+ goto exit;
+ }
}
if (ret > 0) {
r = (struct ec_response_host_event_mask *)msg->data;
*mask = r->mask;
}

+exit:
+ kfree(msg);
return ret;
}

-static int cros_ec_host_command_proto_query(struct cros_ec_device *ec_dev,
- int devidx,
- struct cros_ec_command *msg)
+static int fill_protocol_info(struct cros_ec_device *ec_dev, int devidx)
{
- /*
- * Try using v3+ to query for supported protocols. If this
- * command fails, fall back to v2. Returns the highest protocol
- * supported by the EC.
- * Also sets the max request/response/passthru size.
- */
+ struct cros_ec_command *msg;
+ struct ec_response_get_protocol_info *info;
int ret;

- memset(msg, 0, sizeof(*msg));
+ ec_dev->proto_version = 3;
+ if (devidx > 0)
+ ec_dev->max_passthru = 0;
+
+ msg = kzalloc(sizeof(*msg) + sizeof(*info), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
msg->command = EC_CMD_PASSTHRU_OFFSET(devidx) | EC_CMD_GET_PROTOCOL_INFO;
- msg->insize = sizeof(struct ec_response_get_protocol_info);
+ msg->insize = sizeof(*info);

ret = send_command(ec_dev, msg);
/*
@@ -299,15 +305,43 @@ static int cros_ec_host_command_proto_query(struct cros_ec_device *ec_dev,
dev_dbg(ec_dev->dev,
"failed to check for EC[%d] protocol version: %d\n",
devidx, ret);
- return ret;
+ goto exit;
}

- if (devidx > 0 && msg->result == EC_RES_INVALID_COMMAND)
- return -ENODEV;
- else if (msg->result != EC_RES_SUCCESS)
- return msg->result;
+ ret = cros_ec_map_error(msg->result);
+ if (ret)
+ goto exit;
+
+ info = (struct ec_response_get_protocol_info *)msg->data;
+
+ switch (devidx) {
+ case CROS_EC_DEV_EC_INDEX:
+ ec_dev->max_request = info->max_request_packet_size -
+ sizeof(struct ec_host_request);
+ ec_dev->max_response = info->max_response_packet_size -
+ sizeof(struct ec_host_response);
+ ec_dev->proto_version = min(EC_HOST_REQUEST_VERSION,
+ fls(info->protocol_versions) - 1);
+ ec_dev->din_size = info->max_response_packet_size + EC_MAX_RESPONSE_OVERHEAD;
+ ec_dev->dout_size = info->max_request_packet_size + EC_MAX_REQUEST_OVERHEAD;
+
+ dev_dbg(ec_dev->dev, "using proto v%u\n", ec_dev->proto_version);
+ break;
+ case CROS_EC_DEV_PD_INDEX:
+ ec_dev->max_passthru = info->max_request_packet_size -
+ sizeof(struct ec_host_request);
+
+ dev_dbg(ec_dev->dev, "found PD chip\n");
+ break;
+ default:
+ dev_dbg(ec_dev->dev, "unknwon passthru index: %d\n", devidx);
+ break;
+ }

- return 0;
+ ret = 0;
+exit:
+ kfree(msg);
+ return ret;
}

static int cros_ec_host_command_proto_query_v2(struct cros_ec_device *ec_dev)
@@ -417,51 +451,13 @@ static int cros_ec_get_host_command_version_mask(struct cros_ec_device *ec_dev,
int cros_ec_query_all(struct cros_ec_device *ec_dev)
{
struct device *dev = ec_dev->dev;
- struct cros_ec_command *proto_msg;
- struct ec_response_get_protocol_info *proto_info;
u32 ver_mask = 0;
int ret;

- proto_msg = kzalloc(sizeof(*proto_msg) + sizeof(*proto_info),
- GFP_KERNEL);
- if (!proto_msg)
- return -ENOMEM;
-
/* First try sending with proto v3. */
- ec_dev->proto_version = 3;
- ret = cros_ec_host_command_proto_query(ec_dev, CROS_EC_DEV_EC_INDEX, proto_msg);
-
- if (ret == 0) {
- proto_info = (struct ec_response_get_protocol_info *)
- proto_msg->data;
- ec_dev->max_request = proto_info->max_request_packet_size -
- sizeof(struct ec_host_request);
- ec_dev->max_response = proto_info->max_response_packet_size -
- sizeof(struct ec_host_response);
- ec_dev->proto_version =
- min(EC_HOST_REQUEST_VERSION,
- fls(proto_info->protocol_versions) - 1);
- dev_dbg(ec_dev->dev,
- "using proto v%u\n",
- ec_dev->proto_version);
-
- ec_dev->din_size = proto_info->max_response_packet_size + EC_MAX_RESPONSE_OVERHEAD;
- ec_dev->dout_size = proto_info->max_request_packet_size + EC_MAX_REQUEST_OVERHEAD;
-
- /*
- * Check for PD
- */
- ret = cros_ec_host_command_proto_query(ec_dev, CROS_EC_DEV_PD_INDEX, proto_msg);
-
- if (ret) {
- dev_dbg(ec_dev->dev, "no PD chip found: %d\n", ret);
- ec_dev->max_passthru = 0;
- } else {
- dev_dbg(ec_dev->dev, "found PD chip\n");
- ec_dev->max_passthru =
- proto_info->max_request_packet_size -
- sizeof(struct ec_host_request);
- }
+ if (!fill_protocol_info(ec_dev, CROS_EC_DEV_EC_INDEX)) {
+ /* Check for PD. */
+ fill_protocol_info(ec_dev, CROS_EC_DEV_PD_INDEX);
} else {
/* Try querying with a v2 hello message. */
ec_dev->proto_version = 2;
@@ -524,8 +520,7 @@ int cros_ec_query_all(struct cros_ec_device *ec_dev)
ec_dev->host_sleep_v1 = (ret >= 0 && (ver_mask & EC_VER_MASK(1)));

/* Get host event wake mask. */
- ret = cros_ec_get_host_event_wake_mask(ec_dev, proto_msg,
- &ec_dev->host_event_wake_mask);
+ ret = cros_ec_get_host_event_wake_mask(ec_dev, &ec_dev->host_event_wake_mask);
if (ret < 0) {
/*
* If the EC doesn't support EC_CMD_HOST_EVENT_GET_WAKE_MASK,
@@ -556,7 +551,6 @@ int cros_ec_query_all(struct cros_ec_device *ec_dev)
ret = 0;

exit:
- kfree(proto_msg);
return ret;
}
EXPORT_SYMBOL(cros_ec_query_all);
diff --git a/drivers/platform/chrome/cros_ec_proto_test.c b/drivers/platform/chrome/cros_ec_proto_test.c
index 5169bf33360b..cdedbdfc1885 100644
--- a/drivers/platform/chrome/cros_ec_proto_test.c
+++ b/drivers/platform/chrome/cros_ec_proto_test.c
@@ -194,7 +194,7 @@ static void cros_ec_proto_test_query_all_normal(struct kunit *test)
struct ec_xfer_mock *mock;
int ret;

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
struct ec_response_get_protocol_info *data;

@@ -207,7 +207,7 @@ static void cros_ec_proto_test_query_all_normal(struct kunit *test)
data->max_response_packet_size = 0xef;
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
struct ec_response_get_protocol_info *data;

@@ -255,7 +255,7 @@ static void cros_ec_proto_test_query_all_normal(struct kunit *test)
ret = cros_ec_query_all(ec_dev);
KUNIT_EXPECT_EQ(test, ret, 0);

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -273,7 +273,7 @@ static void cros_ec_proto_test_query_all_normal(struct kunit *test)
KUNIT_EXPECT_EQ(test, ec_dev->dout_size, 0xbe + EC_MAX_REQUEST_OVERHEAD);
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -348,7 +348,7 @@ static void cros_ec_proto_test_query_all_no_pd(struct kunit *test)
struct ec_xfer_mock *mock;
int ret;

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
struct ec_response_get_protocol_info *data;

@@ -364,7 +364,7 @@ static void cros_ec_proto_test_query_all_no_pd(struct kunit *test)
data->max_response_packet_size = 0xef;
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_INVALID_COMMAND,
sizeof(struct ec_response_get_protocol_info));
@@ -375,7 +375,7 @@ static void cros_ec_proto_test_query_all_no_pd(struct kunit *test)
ret = cros_ec_query_all(ec_dev);
KUNIT_EXPECT_EQ(test, ret, 0);

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -387,7 +387,7 @@ static void cros_ec_proto_test_query_all_no_pd(struct kunit *test)
KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0);
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -411,7 +411,7 @@ static void cros_ec_proto_test_query_all_legacy_normal(struct kunit *test)
struct ec_xfer_mock *mock;
int ret;

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_INVALID_COMMAND,
sizeof(struct ec_response_get_protocol_info));
@@ -433,7 +433,7 @@ static void cros_ec_proto_test_query_all_legacy_normal(struct kunit *test)
ret = cros_ec_query_all(ec_dev);
KUNIT_EXPECT_EQ(test, ret, 0);

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -771,7 +771,7 @@ static void cros_ec_proto_test_query_all_default_wake_mask(struct kunit *test)
/* Set some garbage bytes. */
ec_dev->host_event_wake_mask = U32_MAX;

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
struct ec_response_get_protocol_info *data;

@@ -787,7 +787,7 @@ static void cros_ec_proto_test_query_all_default_wake_mask(struct kunit *test)
data->max_response_packet_size = 0xef;
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
mock = cros_kunit_ec_xfer_mock_addx(test, 0, EC_RES_INVALID_COMMAND,
sizeof(struct ec_response_get_protocol_info));
@@ -819,7 +819,7 @@ static void cros_ec_proto_test_query_all_default_wake_mask(struct kunit *test)
ret = cros_ec_query_all(ec_dev);
KUNIT_EXPECT_EQ(test, ret, 0);

- /* For cros_ec_host_command_proto_query() without passthru. */
+ /* For fill_protocol_info() without passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
@@ -831,7 +831,7 @@ static void cros_ec_proto_test_query_all_default_wake_mask(struct kunit *test)
KUNIT_EXPECT_EQ(test, mock->msg.outsize, 0);
}

- /* For cros_ec_host_command_proto_query() with passthru. */
+ /* For fill_protocol_info() with passthru. */
{
mock = cros_kunit_ec_xfer_mock_next();
KUNIT_EXPECT_PTR_NE(test, mock, NULL);
--
2.36.1.255.ge46751e96f-goog