[PATCH] gpio: omap: be more aggressive with pm_runtime

Felipe Balbi balbi at ti.com
Wed Feb 8 08:53:30 EST 2012


Hi,

On Wed, Feb 08, 2012 at 03:26:54PM +0200, Felipe Balbi wrote:
> try to keep gpio block suspended as much as possible.
> 
> Tested with pandaboard and a sysfs exported gpio.
> 
> Signed-off-by: Felipe Balbi <balbi at ti.com>
> ---
> 
> I couldn't see any issues with this patch. I managed to export
> a gpio and change the direction with a while true loop with
> no issues whatsoever.

btw, I also played with gpios 7 and 8 because they have LEDs on them on
pandaboard and everything seems to be fine.

I just want to be sure I can still go to OFF mode and wakeup, but on
vanilla 3.3-rc2 after echo mem > /sys/power/state the systems freezes on
panda, so I can't go any further.

> Any chance someone tells me how to reproduce the original
> wakeup problem we had ?
> 
> I wrote a simple script to dump gpio states while I had:
> 
> while true; do echo in > /sys/class/gpio/gpio2/direction; \
> 	echo out > /sys/class/gpio/gpio2/direction; done &
> 
> running. Here's the ouput:
> 
> ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 11945
> runtime_suspended_time 1214578
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1226468
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1226562
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1226578
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1226593
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 12234
> runtime_suspended_time 1215257
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1227437
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1227531
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1227546
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1227562
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 12460
> runtime_suspended_time 1215882
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1228289
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1228382
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1228398
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1228414
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 12734
> runtime_suspended_time 1216453
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1229132
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1229226
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1229242
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1229257
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status active
> runtime_active_time 13007
> runtime_suspended_time 1216960
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1229914
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230007
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230023
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230039
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 13234
> runtime_suspended_time 1217492
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1230671
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230765
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230781
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1230796
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 13453
> runtime_suspended_time 1218023
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1231421
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1231515
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1231531
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1231546
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 13703
> runtime_suspended_time 1218539
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1232187
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1232281
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1232296
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1232312
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status active
> runtime_active_time 13890
> runtime_suspended_time 1219125
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1232960
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233054
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233070
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233085
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 14109
> runtime_suspended_time 1219601
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1233656
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233750
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233765
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1233781
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 14367
> runtime_suspended_time 1220109
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1234421
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1234515
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1234531
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1234546
> 
> root at legolas:~# ./show_gpios.sh 
> omap_gpio.0
> control auto
> runtime_status suspended
> runtime_active_time 14531
> runtime_suspended_time 1220648
> 
> omap_gpio.1
> control auto
> runtime_status suspended
> runtime_active_time 78
> runtime_suspended_time 1235125
> 
> omap_gpio.2
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1235218
> 
> omap_gpio.3
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1235234
> 
> omap_gpio.4
> control auto
> runtime_status suspended
> runtime_active_time 0
> runtime_suspended_time 1235250
> 
> see that the active time changes for omap_gpio.0 (first gpio bank)
> because I'm constantly changing direction of the exported gpio2, but
> the other banks are kept in suspend state. I even managed to catch
> the gpio bank while it was still in active state. Before suspending
> again.
> 
>  drivers/gpio/gpio-omap.c |   61 +++++++++++++++++++++++++++++++++-------------
>  1 files changed, 44 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index 4273401..2dd9ced 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -537,12 +537,7 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
>  	struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip);
>  	unsigned long flags;
>  
> -	/*
> -	 * If this is the first gpio_request for the bank,
> -	 * enable the bank module.
> -	 */
> -	if (!bank->mod_usage)
> -		pm_runtime_get_sync(bank->dev);
> +	pm_runtime_get_sync(bank->dev);
>  
>  	spin_lock_irqsave(&bank->lock, flags);
>  	/* Set trigger to none. You need to enable the desired trigger with
> @@ -572,6 +567,8 @@ static int omap_gpio_request(struct gpio_chip *chip, unsigned offset)
>  
>  	spin_unlock_irqrestore(&bank->lock, flags);
>  
> +	pm_runtime_put(bank->dev);
> +
>  	return 0;
>  }
>  
> @@ -581,6 +578,8 @@ static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
>  	void __iomem *base = bank->base;
>  	unsigned long flags;
>  
> +	pm_runtime_get_sync(bank->dev);
> +
>  	spin_lock_irqsave(&bank->lock, flags);
>  
>  	if (bank->regs->wkup_en) {
> @@ -606,12 +605,7 @@ static void omap_gpio_free(struct gpio_chip *chip, unsigned offset)
>  	_reset_gpio(bank, bank->chip.base + offset);
>  	spin_unlock_irqrestore(&bank->lock, flags);
>  
> -	/*
> -	 * If this is the last gpio to be freed in the bank,
> -	 * disable the bank module.
> -	 */
> -	if (!bank->mod_usage)
> -		pm_runtime_put(bank->dev);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  /*
> @@ -707,9 +701,11 @@ static void gpio_irq_shutdown(struct irq_data *d)
>  	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
>  	unsigned long flags;
>  
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	_reset_gpio(bank, gpio);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  static void gpio_ack_irq(struct irq_data *d)
> @@ -717,7 +713,9 @@ static void gpio_ack_irq(struct irq_data *d)
>  	unsigned int gpio = d->irq - IH_GPIO_BASE;
>  	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
>  
> +	pm_runtime_get_sync(bank->dev);
>  	_clear_gpio_irqstatus(bank, gpio);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  static void gpio_mask_irq(struct irq_data *d)
> @@ -726,10 +724,12 @@ static void gpio_mask_irq(struct irq_data *d)
>  	struct gpio_bank *bank = irq_data_get_irq_chip_data(d);
>  	unsigned long flags;
>  
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	_set_gpio_irqenable(bank, gpio, 0);
>  	_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  static void gpio_unmask_irq(struct irq_data *d)
> @@ -740,6 +740,7 @@ static void gpio_unmask_irq(struct irq_data *d)
>  	u32 trigger = irqd_get_trigger_type(d);
>  	unsigned long flags;
>  
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	if (trigger)
>  		_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger);
> @@ -753,6 +754,7 @@ static void gpio_unmask_irq(struct irq_data *d)
>  
>  	_set_gpio_irqenable(bank, gpio, 1);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  static struct irq_chip gpio_irq_chip = {
> @@ -836,17 +838,26 @@ static int gpio_input(struct gpio_chip *chip, unsigned offset)
>  	unsigned long flags;
>  
>  	bank = container_of(chip, struct gpio_bank, chip);
> +	pm_runtime_get_sync(bank->dev);
> +
>  	spin_lock_irqsave(&bank->lock, flags);
>  	_set_gpio_direction(bank, offset, 1);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
> +
>  	return 0;
>  }
>  
>  static int gpio_is_input(struct gpio_bank *bank, int mask)
>  {
>  	void __iomem *reg = bank->base + bank->regs->direction;
> +	u32 val;
>  
> -	return __raw_readl(reg) & mask;
> +	pm_runtime_get_sync(bank->dev);
> +	val = __raw_readl(reg) & mask;
> +	pm_runtime_put(bank->dev);
> +
> +	return val;
>  }
>  
>  static int gpio_get(struct gpio_chip *chip, unsigned offset)
> @@ -856,15 +867,20 @@ static int gpio_get(struct gpio_chip *chip, unsigned offset)
>  	int gpio;
>  	u32 mask;
>  
> +	int val;
>  	gpio = chip->base + offset;
>  	bank = container_of(chip, struct gpio_bank, chip);
>  	reg = bank->base;
>  	mask = GPIO_BIT(bank, gpio);
>  
> +	pm_runtime_get_sync(bank->dev);
>  	if (gpio_is_input(bank, mask))
> -		return _get_gpio_datain(bank, gpio);
> +		val = _get_gpio_datain(bank, gpio);
>  	else
> -		return _get_gpio_dataout(bank, gpio);
> +		val = _get_gpio_dataout(bank, gpio);
> +	pm_runtime_put(bank->dev);
> +
> +	return val;
>  }
>  
>  static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
> @@ -873,10 +889,14 @@ static int gpio_output(struct gpio_chip *chip, unsigned offset, int value)
>  	unsigned long flags;
>  
>  	bank = container_of(chip, struct gpio_bank, chip);
> +
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	bank->set_dataout(bank, offset, value);
>  	_set_gpio_direction(bank, offset, 0);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
> +
>  	return 0;
>  }
>  
> @@ -894,9 +914,11 @@ static int gpio_debounce(struct gpio_chip *chip, unsigned offset,
>  			dev_err(bank->dev, "Could not get gpio dbck\n");
>  	}
>  
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	_set_gpio_debounce(bank, offset, debounce);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
>  
>  	return 0;
>  }
> @@ -907,9 +929,12 @@ static void gpio_set(struct gpio_chip *chip, unsigned offset, int value)
>  	unsigned long flags;
>  
>  	bank = container_of(chip, struct gpio_bank, chip);
> +
> +	pm_runtime_get_sync(bank->dev);
>  	spin_lock_irqsave(&bank->lock, flags);
>  	bank->set_dataout(bank, offset, value);
>  	spin_unlock_irqrestore(&bank->lock, flags);
> +	pm_runtime_put(bank->dev);
>  }
>  
>  static int gpio_2irq(struct gpio_chip *chip, unsigned offset)
> @@ -1330,7 +1355,8 @@ void omap2_gpio_prepare_for_idle(int pwr_mode)
>  
>  		bank->power_mode = pwr_mode;
>  
> -		pm_runtime_put_sync_suspend(bank->dev);
> +		if (!pm_runtime_suspended(bank->dev))
> +			pm_runtime_suspend(bank->dev);
>  	}
>  }
>  
> @@ -1342,7 +1368,8 @@ void omap2_gpio_resume_after_idle(void)
>  		if (!bank->mod_usage || !bank->loses_context)
>  			continue;
>  
> -		pm_runtime_get_sync(bank->dev);
> +		if (pm_runtime_suspended(bank->dev))
> +			pm_runtime_resume(bank->dev);
>  	}
>  }
>  
> -- 
> 1.7.9
> 

-- 
balbi
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