2015-09-02 10:04:11

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v3 1/4] Bluetooth: hci_intel: Implement LPM suspend/resume

Add LPM PM suspend/resume/host_wake LPM functions.
A LPM transaction is composed with a LPM request and ack/response.
Host can send a LPM suspend/resume request to the controller which
should respond with a LPM ack.
If resume is requested by the controller (irq), host has to send a LPM
ack once resumed.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: Bracket coding style fixes.
Reorder lpm functions to avoid forward declaration.
v3: Add comment about lpm_transaction failure ignoring

drivers/bluetooth/hci_intel.c | 158 ++++++++++++++++++++++++++++++++++++++++++
1 file changed, 158 insertions(+)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 5d53185..2e15ca5 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -46,12 +46,17 @@
#define STATE_BOOTING 4
#define STATE_LPM_ENABLED 5
#define STATE_TX_ACTIVE 6
+#define STATE_SUSPENDED 7
+#define STATE_LPM_TRANSACTION 8

+#define HCI_LPM_WAKE_PKT 0xf0
#define HCI_LPM_PKT 0xf1
#define HCI_LPM_MAX_SIZE 10
#define HCI_LPM_HDR_SIZE HCI_EVENT_HDR_SIZE

#define LPM_OP_TX_NOTIFY 0x00
+#define LPM_OP_SUSPEND_ACK 0x02
+#define LPM_OP_RESUME_ACK 0x03

struct hci_lpm_pkt {
__u8 opcode;
@@ -129,6 +134,143 @@ static int intel_wait_booting(struct hci_uart *hu)
return err;
}

+static int intel_wait_lpm_transaction(struct hci_uart *hu)
+{
+ struct intel_data *intel = hu->priv;
+ int err;
+
+ err = wait_on_bit_timeout(&intel->flags, STATE_LPM_TRANSACTION,
+ TASK_INTERRUPTIBLE,
+ msecs_to_jiffies(1000));
+
+ if (err == 1) {
+ bt_dev_err(hu->hdev, "LPM transaction interrupted");
+ return -EINTR;
+ }
+
+ if (err) {
+ bt_dev_err(hu->hdev, "LPM transaction timeout");
+ return -ETIMEDOUT;
+ }
+
+ return err;
+}
+
+static int intel_lpm_suspend(struct hci_uart *hu)
+{
+ static const u8 suspend[] = { 0x01, 0x01, 0x01 };
+ struct intel_data *intel = hu->priv;
+ struct sk_buff *skb;
+
+ if (!test_bit(STATE_LPM_ENABLED, &intel->flags) ||
+ test_bit(STATE_SUSPENDED, &intel->flags))
+ return 0;
+
+ if (test_bit(STATE_TX_ACTIVE, &intel->flags))
+ return -EAGAIN;
+
+ bt_dev_dbg(hu->hdev, "Suspending");
+
+ skb = bt_skb_alloc(sizeof(suspend), GFP_KERNEL);
+ if (!skb) {
+ bt_dev_err(hu->hdev, "Failed to alloc memory for LPM packet");
+ return -ENOMEM;
+ }
+
+ memcpy(skb_put(skb, sizeof(suspend)), suspend, sizeof(suspend));
+ bt_cb(skb)->pkt_type = HCI_LPM_PKT;
+
+ set_bit(STATE_LPM_TRANSACTION, &intel->flags);
+
+ skb_queue_tail(&intel->txq, skb);
+ hci_uart_tx_wakeup(hu);
+
+ intel_wait_lpm_transaction(hu);
+ /* Even in case of failure, continue and test the suspended flag */
+
+ clear_bit(STATE_LPM_TRANSACTION, &intel->flags);
+
+ if (!test_bit(STATE_SUSPENDED, &intel->flags)) {
+ bt_dev_err(hu->hdev, "Device suspend error");
+ return -EINVAL;
+ }
+
+ bt_dev_dbg(hu->hdev, "Suspended");
+
+ hci_uart_set_flow_control(hu, true);
+
+ return 0;
+}
+
+static int intel_lpm_resume(struct hci_uart *hu)
+{
+ struct intel_data *intel = hu->priv;
+ struct sk_buff *skb;
+
+ if (!test_bit(STATE_LPM_ENABLED, &intel->flags) ||
+ !test_bit(STATE_SUSPENDED, &intel->flags))
+ return 0;
+
+ bt_dev_dbg(hu->hdev, "Resuming");
+
+ hci_uart_set_flow_control(hu, false);
+
+ skb = bt_skb_alloc(0, GFP_KERNEL);
+ if (!skb) {
+ bt_dev_err(hu->hdev, "Failed to alloc memory for LPM packet");
+ return -ENOMEM;
+ }
+
+ bt_cb(skb)->pkt_type = HCI_LPM_WAKE_PKT;
+
+ set_bit(STATE_LPM_TRANSACTION, &intel->flags);
+
+ skb_queue_tail(&intel->txq, skb);
+ hci_uart_tx_wakeup(hu);
+
+ intel_wait_lpm_transaction(hu);
+ /* Even in case of failure, continue and test the suspended flag */
+
+ clear_bit(STATE_LPM_TRANSACTION, &intel->flags);
+
+ if (test_bit(STATE_SUSPENDED, &intel->flags)) {
+ bt_dev_err(hu->hdev, "Device resume error");
+ return -EINVAL;
+ }
+
+ bt_dev_dbg(hu->hdev, "Resumed");
+
+ return 0;
+}
+
+static int intel_lpm_host_wake(struct hci_uart *hu)
+{
+ static const u8 lpm_resume_ack[] = { LPM_OP_RESUME_ACK, 0x00 };
+ struct intel_data *intel = hu->priv;
+ struct sk_buff *skb;
+
+ hci_uart_set_flow_control(hu, false);
+
+ clear_bit(STATE_SUSPENDED, &intel->flags);
+
+ skb = bt_skb_alloc(sizeof(lpm_resume_ack), GFP_KERNEL);
+ if (!skb) {
+ bt_dev_err(hu->hdev, "Failed to alloc memory for LPM packet");
+ return -ENOMEM;
+ }
+
+ memcpy(skb_put(skb, sizeof(lpm_resume_ack)), lpm_resume_ack,
+ sizeof(lpm_resume_ack));
+ bt_cb(skb)->pkt_type = HCI_LPM_PKT;
+
+ skb_queue_tail(&intel->txq, skb);
+ hci_uart_tx_wakeup(hu);
+
+ bt_dev_dbg(hu->hdev, "Resumed by controller");
+
+ return 0;
+}
+
static irqreturn_t intel_irq(int irq, void *dev_id)
{
struct intel_device *idev = dev_id;
@@ -800,12 +942,28 @@ static void intel_recv_lpm_notify(struct hci_dev *hdev, int value)
static int intel_recv_lpm(struct hci_dev *hdev, struct sk_buff *skb)
{
struct hci_lpm_pkt *lpm = (void *)skb->data;
+ struct hci_uart *hu = hci_get_drvdata(hdev);
+ struct intel_data *intel = hu->priv;

switch (lpm->opcode) {
case LPM_OP_TX_NOTIFY:
if (lpm->dlen)
intel_recv_lpm_notify(hdev, lpm->data[0]);
break;
+ case LPM_OP_SUSPEND_ACK:
+ set_bit(STATE_SUSPENDED, &intel->flags);
+ if (test_and_clear_bit(STATE_LPM_TRANSACTION, &intel->flags)) {
+ smp_mb__after_atomic();
+ wake_up_bit(&intel->flags, STATE_LPM_TRANSACTION);
+ }
+ break;
+ case LPM_OP_RESUME_ACK:
+ clear_bit(STATE_SUSPENDED, &intel->flags);
+ if (test_and_clear_bit(STATE_LPM_TRANSACTION, &intel->flags)) {
+ smp_mb__after_atomic();
+ wake_up_bit(&intel->flags, STATE_LPM_TRANSACTION);
+ }
+ break;
default:
bt_dev_err(hdev, "Unknown LPM opcode (%02x)", lpm->opcode);
break;
--
1.9.1


2015-09-02 15:30:46

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v3 3/4] Bluetooth: hci_intel: Add runtime PM support

Hi Loic,

> Implement runtime PM suspend/resume callbacks.
> If LPM supported, controller is put into supsend after a delay of
> inactivity (1s). Inactivity is based on LPM idle notification and
> host TX traffic.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: Add pm_runtime comments.
> Use same suspend/resume callbacks for pm and runtime pm.
> v3: Fix 'list' indentation.
> Move cancel_work before set_power(0)
>
> drivers/bluetooth/hci_intel.c | 72 +++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 69 insertions(+), 3 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel


2015-09-02 15:29:57

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v3 4/4] Bluetooth: hci_intel: Show error in case of invalid LPM packet size

Hi Loic,

> Don't hide this packet size error.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: no patch 4/4
> v3: Add this patch
>
> drivers/bluetooth/hci_intel.c | 7 +++++--
> 1 file changed, 5 insertions(+), 2 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel


2015-09-02 15:29:36

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v3 2/4] Bluetooth: hci_intel: Add PM support

Hi Loic,

> Add PM suspend/resume callbacks which call lpm_suspend/resume.
> Add LPM ack in threaded IRQ handler to notify the controller that
> resume is complete.
> Protect hci_uart against concurrent removing during suspend/resume.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: Rebase on lpm functions reorder.
> Add idev->hu comment.
> v3: no change
>
> drivers/bluetooth/hci_intel.c | 53 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 53 insertions(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel


2015-09-02 15:29:12

by Marcel Holtmann

[permalink] [raw]
Subject: Re: [PATCH v3 1/4] Bluetooth: hci_intel: Implement LPM suspend/resume

Hi Loic,

> Add LPM PM suspend/resume/host_wake LPM functions.
> A LPM transaction is composed with a LPM request and ack/response.
> Host can send a LPM suspend/resume request to the controller which
> should respond with a LPM ack.
> If resume is requested by the controller (irq), host has to send a LPM
> ack once resumed.
>
> Signed-off-by: Loic Poulain <[email protected]>
> ---
> v2: Bracket coding style fixes.
> Reorder lpm functions to avoid forward declaration.
> v3: Add comment about lpm_transaction failure ignoring
>
> drivers/bluetooth/hci_intel.c | 158 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 158 insertions(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel


2015-09-02 10:04:13

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v3 3/4] Bluetooth: hci_intel: Add runtime PM support

Implement runtime PM suspend/resume callbacks.
If LPM supported, controller is put into supsend after a delay of
inactivity (1s). Inactivity is based on LPM idle notification and
host TX traffic.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: Add pm_runtime comments.
Use same suspend/resume callbacks for pm and runtime pm.
v3: Fix 'list' indentation.
Move cancel_work before set_power(0)

drivers/bluetooth/hci_intel.c | 72 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 69 insertions(+), 3 deletions(-)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 3897e75..9fd1143 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -32,6 +32,7 @@
#include <linux/gpio/consumer.h>
#include <linux/acpi.h>
#include <linux/interrupt.h>
+#include <linux/pm_runtime.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
@@ -58,6 +59,8 @@
#define LPM_OP_SUSPEND_ACK 0x02
#define LPM_OP_RESUME_ACK 0x03

+#define LPM_SUSPEND_DELAY_MS 1000
+
struct hci_lpm_pkt {
__u8 opcode;
__u8 dlen;
@@ -79,6 +82,8 @@ static DEFINE_MUTEX(intel_device_list_lock);
struct intel_data {
struct sk_buff *rx_skb;
struct sk_buff_head txq;
+ struct work_struct busy_work;
+ struct hci_uart *hu;
unsigned long flags;
};

@@ -284,6 +289,11 @@ static irqreturn_t intel_irq(int irq, void *dev_id)
intel_lpm_host_wake(idev->hu);
mutex_unlock(&idev->hu_lock);

+ /* Host/Controller are now LPM resumed, trigger a new delayed suspend */
+ pm_runtime_get(&idev->pdev->dev);
+ pm_runtime_mark_last_busy(&idev->pdev->dev);
+ pm_runtime_put_autosuspend(&idev->pdev->dev);
+
return IRQ_HANDLED;
}

@@ -339,9 +349,17 @@ static int intel_set_power(struct hci_uart *hu, bool powered)
}

device_wakeup_enable(&idev->pdev->dev);
+
+ pm_runtime_set_active(&idev->pdev->dev);
+ pm_runtime_use_autosuspend(&idev->pdev->dev);
+ pm_runtime_set_autosuspend_delay(&idev->pdev->dev,
+ LPM_SUSPEND_DELAY_MS);
+ pm_runtime_enable(&idev->pdev->dev);
} else if (!powered && device_may_wakeup(&idev->pdev->dev)) {
devm_free_irq(&idev->pdev->dev, idev->irq, idev);
device_wakeup_disable(&idev->pdev->dev);
+
+ pm_runtime_disable(&idev->pdev->dev);
}
}

@@ -350,6 +368,28 @@ static int intel_set_power(struct hci_uart *hu, bool powered)
return err;
}

+static void intel_busy_work(struct work_struct *work)
+{
+ struct list_head *p;
+ struct intel_data *intel = container_of(work, struct intel_data,
+ busy_work);
+
+ /* Link is busy, delay the suspend */
+ mutex_lock(&intel_device_list_lock);
+ list_for_each(p, &intel_device_list) {
+ struct intel_device *idev = list_entry(p, struct intel_device,
+ list);
+
+ if (intel->hu->tty->dev->parent == idev->pdev->dev.parent) {
+ pm_runtime_get(&idev->pdev->dev);
+ pm_runtime_mark_last_busy(&idev->pdev->dev);
+ pm_runtime_put_autosuspend(&idev->pdev->dev);
+ break;
+ }
+ }
+ mutex_unlock(&intel_device_list_lock);
+}
+
static int intel_open(struct hci_uart *hu)
{
struct intel_data *intel;
@@ -361,6 +401,9 @@ static int intel_open(struct hci_uart *hu)
return -ENOMEM;

skb_queue_head_init(&intel->txq);
+ INIT_WORK(&intel->busy_work, intel_busy_work);
+
+ intel->hu = hu;

hu->priv = intel;

@@ -376,6 +419,8 @@ static int intel_close(struct hci_uart *hu)

BT_DBG("hu %p", hu);

+ cancel_work_sync(&intel->busy_work);
+
intel_set_power(hu, false);

skb_queue_purge(&intel->txq);
@@ -949,10 +994,12 @@ static void intel_recv_lpm_notify(struct hci_dev *hdev, int value)

bt_dev_dbg(hdev, "TX idle notification (%d)", value);

- if (value)
+ if (value) {
set_bit(STATE_TX_ACTIVE, &intel->flags);
- else
+ schedule_work(&intel->busy_work);
+ } else {
clear_bit(STATE_TX_ACTIVE, &intel->flags);
+ }
}

static int intel_recv_lpm(struct hci_dev *hdev, struct sk_buff *skb)
@@ -1027,9 +1074,27 @@ static int intel_recv(struct hci_uart *hu, const void *data, int count)
static int intel_enqueue(struct hci_uart *hu, struct sk_buff *skb)
{
struct intel_data *intel = hu->priv;
+ struct list_head *p;

BT_DBG("hu %p skb %p", hu, skb);

+ /* Be sure our controller is resumed and potential LPM transaction
+ * completed before enqueuing any packet.
+ */
+ mutex_lock(&intel_device_list_lock);
+ list_for_each(p, &intel_device_list) {
+ struct intel_device *idev = list_entry(p, struct intel_device,
+ list);
+
+ if (hu->tty->dev->parent == idev->pdev->dev.parent) {
+ pm_runtime_get_sync(&idev->pdev->dev);
+ pm_runtime_mark_last_busy(&idev->pdev->dev);
+ pm_runtime_put_autosuspend(&idev->pdev->dev);
+ break;
+ }
+ }
+ mutex_unlock(&intel_device_list_lock);
+
skb_queue_tail(&intel->txq, skb);

return 0;
@@ -1103,7 +1168,7 @@ static int intel_acpi_probe(struct intel_device *idev)
}
#endif

-#ifdef CONFIG_PM_SLEEP
+#ifdef CONFIG_PM
static int intel_suspend(struct device *dev)
{
struct intel_device *idev = dev_get_drvdata(dev);
@@ -1135,6 +1200,7 @@ static int intel_resume(struct device *dev)

static const struct dev_pm_ops intel_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
+ SET_RUNTIME_PM_OPS(intel_suspend, intel_resume, NULL)
};

static int intel_probe(struct platform_device *pdev)
--
1.9.1

2015-09-02 10:04:14

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v3 4/4] Bluetooth: hci_intel: Show error in case of invalid LPM packet size

Don't hide this packet size error.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: no patch 4/4
v3: Add this patch

drivers/bluetooth/hci_intel.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 9fd1143..b4dc3c5 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -1010,8 +1010,11 @@ static int intel_recv_lpm(struct hci_dev *hdev, struct sk_buff *skb)

switch (lpm->opcode) {
case LPM_OP_TX_NOTIFY:
- if (lpm->dlen)
- intel_recv_lpm_notify(hdev, lpm->data[0]);
+ if (lpm->dlen < 1) {
+ bt_dev_err(hu->hdev, "Invalid LPM notification packet");
+ break;
+ }
+ intel_recv_lpm_notify(hdev, lpm->data[0]);
break;
case LPM_OP_SUSPEND_ACK:
set_bit(STATE_SUSPENDED, &intel->flags);
--
1.9.1

2015-09-02 10:04:12

by Loic Poulain

[permalink] [raw]
Subject: [PATCH v3 2/4] Bluetooth: hci_intel: Add PM support

Add PM suspend/resume callbacks which call lpm_suspend/resume.
Add LPM ack in threaded IRQ handler to notify the controller that
resume is complete.
Protect hci_uart against concurrent removing during suspend/resume.

Signed-off-by: Loic Poulain <[email protected]>
---
v2: Rebase on lpm functions reorder.
Add idev->hu comment.
v3: no change

drivers/bluetooth/hci_intel.c | 53 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)

diff --git a/drivers/bluetooth/hci_intel.c b/drivers/bluetooth/hci_intel.c
index 2e15ca5..3897e75 100644
--- a/drivers/bluetooth/hci_intel.c
+++ b/drivers/bluetooth/hci_intel.c
@@ -68,6 +68,8 @@ struct intel_device {
struct list_head list;
struct platform_device *pdev;
struct gpio_desc *reset;
+ struct hci_uart *hu;
+ struct mutex hu_lock;
int irq;
};

@@ -277,6 +279,11 @@ static irqreturn_t intel_irq(int irq, void *dev_id)

dev_info(&idev->pdev->dev, "hci_intel irq\n");

+ mutex_lock(&idev->hu_lock);
+ if (idev->hu)
+ intel_lpm_host_wake(idev->hu);
+ mutex_unlock(&idev->hu_lock);
+
return IRQ_HANDLED;
}

@@ -307,6 +314,15 @@ static int intel_set_power(struct hci_uart *hu, bool powered)

gpiod_set_value(idev->reset, powered);

+ /* Provide to idev a hu reference which is used to run LPM
+ * transactions (lpm suspend/resume) from PM callbacks.
+ * hu needs to be protected against concurrent removing during
+ * these PM ops.
+ */
+ mutex_lock(&idev->hu_lock);
+ idev->hu = powered ? hu : NULL;
+ mutex_unlock(&idev->hu_lock);
+
if (idev->irq < 0)
break;

@@ -1087,6 +1103,40 @@ static int intel_acpi_probe(struct intel_device *idev)
}
#endif

+#ifdef CONFIG_PM_SLEEP
+static int intel_suspend(struct device *dev)
+{
+ struct intel_device *idev = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "intel_suspend");
+
+ mutex_lock(&idev->hu_lock);
+ if (idev->hu)
+ intel_lpm_suspend(idev->hu);
+ mutex_unlock(&idev->hu_lock);
+
+ return 0;
+}
+
+static int intel_resume(struct device *dev)
+{
+ struct intel_device *idev = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "intel_resume");
+
+ mutex_lock(&idev->hu_lock);
+ if (idev->hu)
+ intel_lpm_resume(idev->hu);
+ mutex_unlock(&idev->hu_lock);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops intel_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
+};
+
static int intel_probe(struct platform_device *pdev)
{
struct intel_device *idev;
@@ -1095,6 +1145,8 @@ static int intel_probe(struct platform_device *pdev)
if (!idev)
return -ENOMEM;

+ mutex_init(&idev->hu_lock);
+
idev->pdev = pdev;

if (ACPI_HANDLE(&pdev->dev)) {
@@ -1171,6 +1223,7 @@ static struct platform_driver intel_driver = {
.driver = {
.name = "hci_intel",
.acpi_match_table = ACPI_PTR(intel_acpi_match),
+ .pm = &intel_pm_ops,
},
};

--
1.9.1