This cleans up the locking logic so that the spinlock is consistently used for
access to a small handful of struct variables, and the mutex is exclusively and
consistently used for ensuring that mutliple threads aren't trying to
send/receive reports at the same time. Previously, only some report
transactions were guarded by this mutex, potentially breaking atomicity. The
mutex has been renamed to reflect this usage.
Signed-off-by: Vicki Pfau <vi@xxxxxxxxxxx>
---
drivers/hid/hid-steam.c | 122 +++++++++++++++++++++++-----------------
1 file changed, 69 insertions(+), 53 deletions(-)
diff --git a/drivers/hid/hid-steam.c b/drivers/hid/hid-steam.c
index efd297e0ea8c..57cb58941c9f 100644
--- a/drivers/hid/hid-steam.c
+++ b/drivers/hid/hid-steam.c
@@ -124,7 +124,7 @@ struct steam_device {
struct list_head list;
spinlock_t lock;
struct hid_device *hdev, *client_hdev;
- struct mutex mutex;
+ struct mutex report_mutex;
bool client_opened;
struct input_dev __rcu *input;
unsigned long quirks;
@@ -267,21 +267,26 @@ static int steam_get_serial(struct steam_device *steam)
* Send: 0xae 0x15 0x01
* Recv: 0xae 0x15 0x01 serialnumber (10 chars)
*/
- int ret;
+ int ret = 0;
u8 cmd[] = {STEAM_CMD_GET_SERIAL, 0x15, 0x01};
u8 reply[3 + STEAM_SERIAL_LEN + 1];
+ mutex_lock(&steam->report_mutex);
ret = steam_send_report(steam, cmd, sizeof(cmd));
if (ret < 0)
- return ret;
+ goto out;
ret = steam_recv_report(steam, reply, sizeof(reply));
if (ret < 0)
- return ret;
- if (reply[0] != 0xae || reply[1] != 0x15 || reply[2] != 0x01)
- return -EIO;
+ goto out;
+ if (reply[0] != 0xae || reply[1] != 0x15 || reply[2] != 0x01) {
+ ret = -EIO;
+ goto out;
+ }
reply[3 + STEAM_SERIAL_LEN] = 0;
strscpy(steam->serial_no, reply + 3, sizeof(steam->serial_no));
- return 0;
+out:
+ mutex_unlock(&steam->report_mutex);
+ return ret;
}
/*
@@ -291,13 +296,18 @@ static int steam_get_serial(struct steam_device *steam)
*/
static inline int steam_request_conn_status(struct steam_device *steam)
{
- return steam_send_report_byte(steam, STEAM_CMD_REQUEST_COMM_STATUS);
+ int ret;
+ mutex_lock(&steam->report_mutex);
+ ret = steam_send_report_byte(steam, STEAM_CMD_REQUEST_COMM_STATUS);
+ mutex_unlock(&steam->report_mutex);
+ return ret;
}
static inline int steam_haptic_rumble(struct steam_device *steam,
u16 intensity, u16 left_speed, u16 right_speed,
u8 left_gain, u8 right_gain)
{
+ int ret;
u8 report[11] = {STEAM_CMD_HAPTIC_RUMBLE, 9};
report[3] = intensity & 0xFF;
@@ -309,7 +319,10 @@ static inline int steam_haptic_rumble(struct steam_device *steam,
report[9] = left_gain;
report[10] = right_gain;
- return steam_send_report(steam, report, sizeof(report));
+ mutex_lock(&steam->report_mutex);
+ ret = steam_send_report(steam, report, sizeof(report));
+ mutex_unlock(&steam->report_mutex);
+ return ret;
}
static void steam_haptic_rumble_cb(struct work_struct *work)
@@ -336,11 +349,14 @@ static int steam_play_effect(struct input_dev *dev, void *data,
static void steam_set_lizard_mode(struct steam_device *steam, bool enable)
{
if (enable) {
+ mutex_lock(&steam->report_mutex);
/* enable esc, enter, cursors */
steam_send_report_byte(steam, STEAM_CMD_DEFAULT_MAPPINGS);
/* enable mouse */
steam_send_report_byte(steam, STEAM_CMD_DEFAULT_MOUSE);
+ mutex_unlock(&steam->report_mutex);
} else {
+ mutex_lock(&steam->report_mutex);
/* disable esc, enter, cursor */
steam_send_report_byte(steam, STEAM_CMD_CLEAR_MAPPINGS);
@@ -352,11 +368,13 @@ static void steam_set_lizard_mode(struct steam_device *steam, bool enable)
STEAM_REG_RPAD_CLICK_PRESSURE, 0xFFFF, /* disable clicky pad */
STEAM_REG_WATCHDOG_ENABLE, 0, /* disable watchdog that tests if Steam is active */
0);
+ mutex_unlock(&steam->report_mutex);
} else {
steam_write_registers(steam,
STEAM_REG_LPAD_MODE, 0x07, /* disable mouse */
STEAM_REG_RPAD_MODE, 0x07, /* disable mouse */
0);
+ mutex_unlock(&steam->report_mutex);
}
}
}
@@ -364,22 +382,29 @@ static void steam_set_lizard_mode(struct steam_device *steam, bool enable)
static int steam_input_open(struct input_dev *dev)
{
struct steam_device *steam = input_get_drvdata(dev);
+ unsigned long flags;
+ bool set_lizard_mode;
- mutex_lock(&steam->mutex);
- if (!steam->client_opened && lizard_mode)
+ spin_lock_irqsave(&steam->lock, flags);
+ set_lizard_mode = !steam->client_opened && lizard_mode;
+ spin_unlock_irqrestore(&steam->lock, flags);
+ if (set_lizard_mode)
steam_set_lizard_mode(steam, false);
- mutex_unlock(&steam->mutex);
+
return 0;
}
static void steam_input_close(struct input_dev *dev)
{
struct steam_device *steam = input_get_drvdata(dev);
+ unsigned long flags;
+ bool set_lizard_mode;
- mutex_lock(&steam->mutex);
- if (!steam->client_opened && lizard_mode)
+ spin_lock_irqsave(&steam->lock, flags);
+ set_lizard_mode = !steam->client_opened && lizard_mode;
+ spin_unlock_irqrestore(&steam->lock, flags);
+ if (set_lizard_mode)
steam_set_lizard_mode(steam, true);
- mutex_unlock(&steam->mutex);
}
static enum power_supply_property steam_battery_props[] = {
@@ -624,6 +649,7 @@ static int steam_register(struct steam_device *steam)
{
int ret;
bool client_opened;
+ unsigned long flags;
/*
* This function can be called several times in a row with the
@@ -636,11 +662,9 @@ static int steam_register(struct steam_device *steam)
* Unlikely, but getting the serial could fail, and it is not so
* important, so make up a serial number and go on.
*/
- mutex_lock(&steam->mutex);
if (steam_get_serial(steam) < 0)
strscpy(steam->serial_no, "XXXXXXXXXX",
sizeof(steam->serial_no));
- mutex_unlock(&steam->mutex);
hid_info(steam->hdev, "Steam Controller '%s' connected",
steam->serial_no);
@@ -655,15 +679,13 @@ static int steam_register(struct steam_device *steam)
mutex_unlock(&steam_devices_lock);
}
- mutex_lock(&steam->mutex);
+ spin_lock_irqsave(&steam->lock, flags);
client_opened = steam->client_opened;
- if (!client_opened)
+ spin_unlock_irqrestore(&steam->lock, flags);
+ if (!client_opened) {
steam_set_lizard_mode(steam, lizard_mode);
- mutex_unlock(&steam->mutex);
-
- if (!client_opened)
ret = steam_input_register(steam);
- else
+ } else
ret = 0;
return ret;
@@ -746,10 +768,11 @@ static void steam_client_ll_stop(struct hid_device *hdev)
static int steam_client_ll_open(struct hid_device *hdev)
{
struct steam_device *steam = hdev->driver_data;
+ unsigned long flags;
- mutex_lock(&steam->mutex);
+ spin_lock_irqsave(&steam->lock, flags);
steam->client_opened = true;
- mutex_unlock(&steam->mutex);
+ spin_unlock_irqrestore(&steam->lock, flags);
steam_input_unregister(steam);
@@ -764,17 +787,14 @@ static void steam_client_ll_close(struct hid_device *hdev)
bool connected;
spin_lock_irqsave(&steam->lock, flags);
- connected = steam->connected;
+ steam->client_opened = false;
+ connected = steam->connected && !steam->client_opened;
spin_unlock_irqrestore(&steam->lock, flags);
- mutex_lock(&steam->mutex);
- steam->client_opened = false;
- if (connected)
+ if (connected) {
steam_set_lizard_mode(steam, lizard_mode);
- mutex_unlock(&steam->mutex);
-
- if (connected)
steam_input_register(steam);
+ }
}
static int steam_client_ll_raw_request(struct hid_device *hdev,
@@ -860,19 +880,12 @@ static int steam_probe(struct hid_device *hdev,
steam->hdev = hdev;
hid_set_drvdata(hdev, steam);
spin_lock_init(&steam->lock);
- mutex_init(&steam->mutex);
+ mutex_init(&steam->report_mutex);
steam->quirks = id->driver_data;
INIT_WORK(&steam->work_connect, steam_work_connect_cb);
INIT_LIST_HEAD(&steam->list);
INIT_WORK(&steam->rumble_work, steam_haptic_rumble_cb);
- steam->client_hdev = steam_create_client_hid(hdev);
- if (IS_ERR(steam->client_hdev)) {
- ret = PTR_ERR(steam->client_hdev);
- goto client_hdev_fail;
- }
- steam->client_hdev->driver_data = steam;
-
/*
* With the real steam controller interface, do not connect hidraw.
* Instead, create the client_hid and connect that.
@@ -881,10 +894,6 @@ static int steam_probe(struct hid_device *hdev,
if (ret)
goto hid_hw_start_fail;
- ret = hid_add_device(steam->client_hdev);
- if (ret)
- goto client_hdev_add_fail;
-
ret = hid_hw_open(hdev);
if (ret) {
hid_err(hdev,
@@ -910,15 +919,26 @@ static int steam_probe(struct hid_device *hdev,
}
}
+ steam->client_hdev = steam_create_client_hid(hdev);
+ if (IS_ERR(steam->client_hdev)) {
+ ret = PTR_ERR(steam->client_hdev);
+ goto client_hdev_fail;
+ }
+ steam->client_hdev->driver_data = steam;
+
+ ret = hid_add_device(steam->client_hdev);
+ if (ret)
+ goto client_hdev_add_fail;
+
return 0;
-input_register_fail:
-hid_hw_open_fail:
client_hdev_add_fail:
hid_hw_stop(hdev);
-hid_hw_start_fail:
- hid_destroy_device(steam->client_hdev);
client_hdev_fail:
+ hid_destroy_device(steam->client_hdev);
+input_register_fail:
+hid_hw_open_fail:
+hid_hw_start_fail:
cancel_work_sync(&steam->work_connect);
cancel_work_sync(&steam->rumble_work);
steam_alloc_fail:
@@ -936,12 +956,10 @@ static void steam_remove(struct hid_device *hdev)
return;
}
+ cancel_work_sync(&steam->work_connect);
hid_destroy_device(steam->client_hdev);
- mutex_lock(&steam->mutex);
steam->client_hdev = NULL;
steam->client_opened = false;
- mutex_unlock(&steam->mutex);
- cancel_work_sync(&steam->work_connect);
if (steam->quirks & STEAM_QUIRK_WIRELESS) {
hid_info(hdev, "Steam wireless receiver disconnected");
}
@@ -1408,10 +1426,8 @@ static int steam_param_set_lizard_mode(const char *val,
mutex_lock(&steam_devices_lock);
list_for_each_entry(steam, &steam_devices, list) {
- mutex_lock(&steam->mutex);
if (!steam->client_opened)
steam_set_lizard_mode(steam, lizard_mode);
- mutex_unlock(&steam->mutex);
}
mutex_unlock(&steam_devices_lock);
return 0;
--
2.42.0
