Adds autosuspend runtime functionality to BCM UART driver.
Autosuspend is enabled at end of bcm_setup.
Add a work queue to be able to perform pm_runtime commands during bcm_recv
which is called by hci_uart_tty_receive() under spinlock.
Signed-off-by: Frederic Danis <frederic.danis@xxxxxxxxxxxxxxx>
---
drivers/bluetooth/hci_bcm.c | 111 ++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 107 insertions(+), 4 deletions(-)
diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 7f63f2b..a226249 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -33,6 +33,7 @@
#include <linux/tty.h>
#include <linux/interrupt.h>
#include <linux/dmi.h>
+#include <linux/pm_runtime.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
@@ -40,6 +41,8 @@
#include "btbcm.h"
#include "hci_uart.h"
+#define BCM_AUTOSUSPEND_DELAY 5000 /* default autosleep delay */
+
struct bcm_device {
struct list_head list;
@@ -67,6 +70,9 @@ struct bcm_data {
struct sk_buff_head txq;
struct bcm_device *dev;
+#ifdef CONFIG_PM
+ struct work_struct pm_work;
+#endif
};
/* List of BCM BT UART devices */
@@ -160,6 +166,10 @@ static irqreturn_t bcm_host_wake(int irq, void *data)
bt_dev_dbg(bdev, "Host wake IRQ");
+ pm_runtime_get(&bdev->pdev->dev);
+ pm_runtime_mark_last_busy(&bdev->pdev->dev);
+ pm_runtime_put_autosuspend(&bdev->pdev->dev);
+
return IRQ_HANDLED;
}
@@ -183,6 +193,12 @@ static int bcm_request_irq(struct bcm_data *bcm)
goto unlock;
device_init_wakeup(&bdev->pdev->dev, true);
+
+ pm_runtime_set_autosuspend_delay(&bdev->pdev->dev,
+ BCM_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(&bdev->pdev->dev);
+ pm_runtime_set_active(&bdev->pdev->dev);
+ pm_runtime_enable(&bdev->pdev->dev);
}
unlock:
@@ -198,7 +214,7 @@ static const struct bcm_set_sleep_mode default_sleep_params = {
.bt_wake_active = 1, /* BT_WAKE active mode: 1 = high, 0 = low */
.host_wake_active = 0, /* HOST_WAKE active mode: 1 = high, 0 = low */
.allow_host_sleep = 1, /* Allow host sleep in SCO flag */
- .combine_modes = 0, /* Combine sleep and LPM flag */
+ .combine_modes = 1, /* Combine sleep and LPM flag */
.tristate_control = 0, /* Allow tri-state control of UART tx flag */
/* Irrelevant USB flags */
.usb_auto_sleep = 0,
@@ -228,9 +244,28 @@ static int bcm_setup_sleep(struct hci_uart *hu)
return 0;
}
+
+static void bcm_pm_runtime_work(struct work_struct *work)
+{
+ struct bcm_data *bcm = container_of(work, struct bcm_data, pm_work);
+
+ mutex_lock(&bcm_device_lock);
+ if (bcm_device_exists(bcm->dev)) {
+ pm_runtime_get(&bcm->dev->pdev->dev);
+ pm_runtime_mark_last_busy(&bcm->dev->pdev->dev);
+ pm_runtime_put_autosuspend(&bcm->dev->pdev->dev);
+ }
+ mutex_unlock(&bcm_device_lock);
+}
+
+static bool bcm_schedule_work(struct bcm_data *bcm)
+{
+ return schedule_work(&bcm->pm_work);
+}
#else
static inline int bcm_request_irq(struct bcm_data *bcm) { return 0; }
static inline int bcm_setup_sleep(struct hci_uart *hu) { return 0; }
+static inline bool bcm_schedule_work(struct bcm_data *bcm) { return false; }
#endif
static int bcm_open(struct hci_uart *hu)
@@ -261,6 +296,7 @@ static int bcm_open(struct hci_uart *hu)
hu->init_speed = dev->init_speed;
#ifdef CONFIG_PM
dev->hu = hu;
+ INIT_WORK(&bcm->pm_work, bcm_pm_runtime_work);
#endif
bcm_gpio_set_power(bcm->dev, true);
break;
@@ -284,6 +320,11 @@ static int bcm_close(struct hci_uart *hu)
if (bcm_device_exists(bdev)) {
bcm_gpio_set_power(bdev, false);
#ifdef CONFIG_PM
+ cancel_work_sync(&bcm->pm_work);
+
+ pm_runtime_disable(&bdev->pdev->dev);
+ pm_runtime_set_suspended(&bdev->pdev->dev);
+
if (device_can_wakeup(&bdev->pdev->dev)) {
devm_free_irq(&bdev->pdev->dev, bdev->irq, bdev);
device_init_wakeup(&bdev->pdev->dev, false);
@@ -393,6 +434,13 @@ static int bcm_recv(struct hci_uart *hu, const void *data, int count)
if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
return -EUNATCH;
+ /* mutex_lock/unlock can not be used here as this function is called
+ * from hci_uart_tty_receive under spinlock.
+ * Defer pm_runtime_* calls to work queue
+ */
+ if (bcm->dev)
+ bcm_schedule_work(bcm);
+
bcm->rx_skb = h4_recv_buf(hu->hdev, bcm->rx_skb, data, count,
bcm_recv_pkts, ARRAY_SIZE(bcm_recv_pkts));
if (IS_ERR(bcm->rx_skb)) {
@@ -421,8 +469,27 @@ static int bcm_enqueue(struct hci_uart *hu, struct sk_buff *skb)
static struct sk_buff *bcm_dequeue(struct hci_uart *hu)
{
struct bcm_data *bcm = hu->priv;
+ struct sk_buff *skb = NULL;
+ struct bcm_device *bdev = NULL;
+
+ mutex_lock(&bcm_device_lock);
+
+ if (bcm_device_exists(bcm->dev)) {
+ bdev = bcm->dev;
+ pm_runtime_get_sync(&bdev->pdev->dev);
+ /* Shall be resumed here */
+ }
+
+ skb = skb_dequeue(&bcm->txq);
+
+ if (bdev) {
+ pm_runtime_mark_last_busy(&bdev->pdev->dev);
+ pm_runtime_put_autosuspend(&bdev->pdev->dev);
+ }
- return skb_dequeue(&bcm->txq);
+ mutex_unlock(&bcm_device_lock);
+
+ return skb;
}
#ifdef CONFIG_PM
@@ -458,6 +525,34 @@ static void __bcm_resume(struct bcm_device *bdev)
hci_uart_set_flow_control(bdev->hu, false);
}
}
+
+static int bcm_runtime_suspend(struct device *dev)
+{
+ struct bcm_device *bdev = platform_get_drvdata(to_platform_device(dev));
+
+ bt_dev_dbg(bdev, "");
+
+ /* bcm_device_lock held is not required here as bcm_runtime_suspend
+ * is only called when device is attached.
+ */
+ __bcm_suspend(bdev);
+
+ return 0;
+}
+
+static int bcm_runtime_resume(struct device *dev)
+{
+ struct bcm_device *bdev = platform_get_drvdata(to_platform_device(dev));
+
+ bt_dev_dbg(bdev, "");
+
+ /* bcm_device_lock held is not required here as bcm_runtime_resume
+ * is only called when device is attached.
+ */
+ __bcm_resume(bdev);
+
+ return 0;
+}
#endif
#ifdef CONFIG_PM_SLEEP
@@ -474,7 +569,8 @@ static int bcm_suspend(struct device *dev)
if (!bdev->hu)
goto unlock;
- __bcm_suspend(bdev);
+ if (pm_runtime_active(dev))
+ __bcm_suspend(bdev);
if (device_may_wakeup(&bdev->pdev->dev)) {
error = enable_irq_wake(bdev->irq);
@@ -510,6 +606,10 @@ static int bcm_resume(struct device *dev)
unlock:
mutex_unlock(&bcm_device_lock);
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
return 0;
}
#endif
@@ -726,7 +826,10 @@ MODULE_DEVICE_TABLE(acpi, bcm_acpi_match);
#endif
/* Platform suspend and resume callbacks */
-static SIMPLE_DEV_PM_OPS(bcm_pm_ops, bcm_suspend, bcm_resume);
+static const struct dev_pm_ops bcm_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(bcm_suspend, bcm_resume)
+ SET_RUNTIME_PM_OPS(bcm_runtime_suspend, bcm_runtime_resume, NULL)
