Re: [PATCH v2 4/4] pinctrl: bcm2835: Add support for wake-up interrupts

[Florian Fainelli <f.fainelli@gmail.com>]

On 5/30/2020 12:49 AM, Stefan Wahren wrote:
> Hi Florian,
> 
> Am 29.05.20 um 21:15 schrieb Florian Fainelli:
>> Leverage the IRQCHIP_MASK_ON_SUSPEND flag in order to avoid having to
>> specifically treat the GPIO interrupts during suspend and resume, and
>> simply implement an irq_set_wake() callback that is responsible for
>> enabling the parent wake-up interrupt as a wake-up interrupt.
>>
>> To avoid allocating unnecessary resources for other chips, the wake-up
>> interrupts are only initialized if we have a brcm,bcm7211-gpio
>> compatibility string.
>>
>> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
>> ---
>>  drivers/pinctrl/bcm/pinctrl-bcm2835.c | 76 ++++++++++++++++++++++++++-
>>  1 file changed, 75 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/pinctrl/bcm/pinctrl-bcm2835.c b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
>> index 1b00d93aa66e..1fbf067a3eed 100644
>> --- a/drivers/pinctrl/bcm/pinctrl-bcm2835.c
>> +++ b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
>> @@ -19,6 +19,7 @@
>>  #include <linux/irq.h>
>>  #include <linux/irqdesc.h>
>>  #include <linux/init.h>
>> +#include <linux/interrupt.h>
>>  #include <linux/of_address.h>
>>  #include <linux/of.h>
>>  #include <linux/of_irq.h>
>> @@ -76,6 +77,7 @@
>>  struct bcm2835_pinctrl {
>>  	struct device *dev;
>>  	void __iomem *base;
>> +	int *wake_irq;
>>  
>>  	/* note: locking assumes each bank will have its own unsigned long */
>>  	unsigned long enabled_irq_map[BCM2835_NUM_BANKS];
>> @@ -435,6 +437,11 @@ static void bcm2835_gpio_irq_handler(struct irq_desc *desc)
>>  	chained_irq_exit(host_chip, desc);
>>  }
>>  
>> +static irqreturn_t bcm2835_gpio_wake_irq_handler(int irq, void *dev_id)
>> +{
>> +	return IRQ_HANDLED;
>> +}
>> +
>>  static inline void __bcm2835_gpio_irq_config(struct bcm2835_pinctrl *pc,
>>  	unsigned reg, unsigned offset, bool enable)
>>  {
>> @@ -634,6 +641,34 @@ static void bcm2835_gpio_irq_ack(struct irq_data *data)
>>  	bcm2835_gpio_set_bit(pc, GPEDS0, gpio);
>>  }
>>  
>> +static int bcm2835_gpio_irq_set_wake(struct irq_data *data, unsigned int on)
>> +{
>> +	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
>> +	struct bcm2835_pinctrl *pc = gpiochip_get_data(chip);
>> +	unsigned gpio = irqd_to_hwirq(data);
>> +	unsigned int irqgroup;
>> +	int ret = -EINVAL;
>> +
>> +	if (!pc->wake_irq)
>> +		return ret;
>> +
>> +	if (gpio <= 27)
>> +		irqgroup = 0;
>> +	else if (gpio >= 28 && gpio <= 45)
>> +		irqgroup = 1;
>> +	else if (gpio >= 46 && gpio <= 53)
>> +		irqgroup = 2;
> in case the BCM7211 has 58 GPIOs, but the wake up interrupts are only
> available for the first 54 this should deserve a comment.

irqgroup 2 covers GPIOs 46 through 57, thanks for noticing. Do you have
more comments before I spin a v3? Thank you for reviewing.
-- 
Florian