Re: [PATCH v2 3/4] Bluetooth: hci_bcm: Prepare PM runtime support

[Frederic Danis <frederic.danis@linux.intel.com>]

Hello Marcel,

On 04/09/2015 20:51, Marcel Holtmann wrote:
> Hi Fred,
>
>> Change some CONFIG_PM_SLEEP to CONFIG_PM as hu and is_suspended parameters
>> will be used during PM runtime callbacks.
>>
>> Add __bcm_suspend() and __bcm_resume() which performs link management for
>> PM callbacks.
>>
>> Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com>
>> ---
>> drivers/bluetooth/hci_bcm.c | 70 ++++++++++++++++++++++++++-------------------
>> 1 file changed, 41 insertions(+), 29 deletions(-)
>>
>> diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
>> index efb9566..7f63f2b 100644
>> --- a/drivers/bluetooth/hci_bcm.c
>> +++ b/drivers/bluetooth/hci_bcm.c
>> @@ -56,7 +56,7 @@ struct bcm_device {
>> 	int			irq;
>> 	u8			irq_polarity;
>>
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_PM
>> 	struct hci_uart		*hu;
>> 	bool			is_suspended; /* suspend/resume flag */
>> #endif
>> @@ -153,7 +153,7 @@ static int bcm_gpio_set_power(struct bcm_device *dev, bool powered)
>> 	return 0;
>> }
>>
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_PM
>> static irqreturn_t bcm_host_wake(int irq, void *data)
>> {
>> 	struct bcm_device *bdev = data;
>> @@ -259,7 +259,7 @@ static int bcm_open(struct hci_uart *hu)
>> 		if (hu->tty->dev->parent == dev->pdev->dev.parent) {
>> 			bcm->dev = dev;
>> 			hu->init_speed = dev->init_speed;
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_PM
>> 			dev->hu = hu;
>> #endif
>> 			bcm_gpio_set_power(bcm->dev, true);
>> @@ -283,7 +283,7 @@ static int bcm_close(struct hci_uart *hu)
>> 	mutex_lock(&bcm_device_lock);
>> 	if (bcm_device_exists(bdev)) {
>> 		bcm_gpio_set_power(bdev, false);
>> -#ifdef CONFIG_PM_SLEEP
>> +#ifdef CONFIG_PM
>> 		if (device_can_wakeup(&bdev->pdev->dev)) {
>> 			devm_free_irq(&bdev->pdev->dev, bdev->irq, bdev);
>> 			device_init_wakeup(&bdev->pdev->dev, false);
>> @@ -425,6 +425,41 @@ static struct sk_buff *bcm_dequeue(struct hci_uart *hu)
>> 	return skb_dequeue(&bcm->txq);
>> }
>>
>> +#ifdef CONFIG_PM
>> +static void __bcm_suspend(struct bcm_device *bdev)
>> +{
>> +	if (!bdev->is_suspended && bdev->hu) {
>> +		hci_uart_set_flow_control(bdev->hu, true);
>> +
>> +		/* Once this returns, driver suspends BT via GPIO */
>> +		bdev->is_suspended = true;
>> +	}
>> +
>> +	/* Suspend the device */
>> +	if (bdev->device_wakeup) {
>> +		gpiod_set_value(bdev->device_wakeup, false);
>> +		bt_dev_dbg(bdev, "suspend, delaying 15 ms");
>> +		mdelay(15);
>> +	}
>> +}
>> +
>> +static void __bcm_resume(struct bcm_device *bdev)
>> +{
>> +	if (bdev->device_wakeup) {
>> +		gpiod_set_value(bdev->device_wakeup, true);
>> +		bt_dev_dbg(bdev, "resume, delaying 15 ms");
>> +		mdelay(15);
>> +	}
>> +
>> +	/* When this executes, the device has woken up already */
>> +	if (bdev->is_suspended && bdev->hu) {
>> +		bdev->is_suspended = false;
>> +
>> +		hci_uart_set_flow_control(bdev->hu, false);
>> +	}
>> +}
>> +#endif
>> +
>> #ifdef CONFIG_PM_SLEEP
>> /* Platform suspend callback */
>> static int bcm_suspend(struct device *dev)
>> @@ -439,19 +474,7 @@ static int bcm_suspend(struct device *dev)
>> 	if (!bdev->hu)
>> 		goto unlock;
>>
>> -	if (!bdev->is_suspended) {
>> -		hci_uart_set_flow_control(bdev->hu, true);
>> -
>> -		/* Once this callback returns, driver suspends BT via GPIO */
>> -		bdev->is_suspended = true;
>> -	}
>> -
>> -	/* Suspend the device */
>> -	if (bdev->device_wakeup) {
>> -		gpiod_set_value(bdev->device_wakeup, false);
>> -		bt_dev_dbg(bdev, "suspend, delaying 15 ms");
>> -		mdelay(15);
>> -	}
>> +	__bcm_suspend(bdev);
>
> I do not see a reason for this change and this will also cause compile time warnings since the code is now behind different config options.

I checked this and do not get any warning as CONFIG_PM_SLEEP selects 
CONFIG_PM.

> You have to give me a bit of better description on what this change is actually for.

This is the common part of runtime suspend and system sleep functions.
Please, see my reply to your comments on patch 4/4.

Regards

Fred