Subject: [PATCH V2 3/3] mfd: palmas: Add support for optional wakeup

From: [email-masked] (Nishanth Menon)
Date: Thu, 18 Sep 2014 08:54:23 -0500

On 09/08/2014 10:41 AM, Nishanth Menon wrote:
> On 23:13-20140905, Thomas Gleixner wrote:
>> On Fri, 5 Sep 2014, Nishanth Menon wrote:
>>> +	if (!palmas->wakeirq)
>>> +		goto no_wake_irq;
>>> +
>>> +	ret = devm_request_irq(palmas->dev, palmas->wakeirq,
>>> +			       palmas_wake_irq,
>>> +			       IRQF_ONESHOT | pdata->irq_flags,
>>
>> Why is this marked IRQF_ONESHOT?
> 
> Uggh.. should have dropped it. my bad.. removed in the revision below.
> Thanks for catching it.
>>
>>> +			       dev_name(palmas->dev),
>>> +			       &palmas);
>>> +	if (ret < 0)
>>> +		goto err_i2c;
>>
>> Why err and not doing the obvious clearing of palmas->wakeirq and
>> keep at least the i2c functional?
> Hmmm.. true.. we can stay alive even though without wakeup capability if
> someone messes up configuration..
> 
> Fixed version below. Let me know if you are ok with the following.

Gentle ping. Would you like me to repost this series over again?

> ----8<----
> From 6da58ac66eedea46cf7282c6644c76c8f328f5ee Mon Sep 17 00:00:00 2001
> From: Nishanth Menon <[email-masked]>
> Date: Tue, 12 Aug 2014 12:00:52 -0500
> Subject: [PATCH V3 3/3] mfd: palmas: Add support for optional wakeup
> 
> With the recent pinctrl-single changes, omaps can treat wake-up events
> from deeper power  states as interrupts.
> 
> This is to handle the case where the system needs two interrupt
> sources when SoC is in deep sleep(1 to exit from deep power mode such
> as sleep, and other from the module handling the actual event during
> system active state). This is not the same as threaded interrupts as the
> wakeup interrupt source is used only as part of deeper power saving
> mode.
> 
> Let's add support for the optional second interrupt for wake-up
> events. And then SoC can wakeup and handle the event using it's
> regular handler.
> 
> This is similar in approach to commit 2a0b965cfb6e ("serial: omap: Add
> support for optional wake-up")
> 
> Signed-off-by: Nishanth Menon <[email-masked]>
> ---
>  drivers/mfd/palmas.c       |   62 ++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/palmas.h |    2 ++
>  2 files changed, 64 insertions(+)
> 
> diff --git a/drivers/mfd/palmas.c b/drivers/mfd/palmas.c
> index 28cb048..de7d204 100644
> --- a/drivers/mfd/palmas.c
> +++ b/drivers/mfd/palmas.c
> @@ -24,6 +24,7 @@
>  #include <linux/mfd/core.h>
>  #include <linux/mfd/palmas.h>
>  #include <linux/of_device.h>
> +#include <linux/of_irq.h>
>  
>  static const struct regmap_config palmas_regmap_config[PALMAS_NUM_CLIENTS] = {
>  	{
> @@ -326,6 +327,16 @@ static struct regmap_irq_chip tps65917_irq_chip = {
>  			PALMAS_INT1_MASK),
>  };
>  
> +static irqreturn_t palmas_wake_irq(int irq, void *_palmas)
> +{
> +	/*
> +	 * Return Not handled so that interrupt is disabled.
> +	 * Level event ensures that the event is eventually handled
> +	 * by the appropriate chip handler already registered
> +	 */
> +	return IRQ_NONE;
> +}
> +
>  int palmas_ext_control_req_config(struct palmas *palmas,
>  	enum palmas_external_requestor_id id,  int ext_ctrl, bool enable)
>  {
> @@ -409,6 +420,7 @@ static void palmas_dt_to_pdata(struct i2c_client *i2c,
>  		pdata->mux_from_pdata = 1;
>  		pdata->pad2 = prop;
>  	}
> +	pdata->wakeirq = irq_of_parse_and_map(node, 1);
>  
>  	/* The default for this register is all masked */
>  	ret = of_property_read_u32(node, "ti,power-ctrl", &prop);
> @@ -521,6 +533,7 @@ static int palmas_i2c_probe(struct i2c_client *i2c,
>  	i2c_set_clientdata(i2c, palmas);
>  	palmas->dev = &i2c->dev;
>  	palmas->irq = i2c->irq;
> +	palmas->wakeirq = pdata->wakeirq;
>  
>  	match = of_match_device(of_palmas_match_tbl, &i2c->dev);
>  
> @@ -587,6 +600,25 @@ static int palmas_i2c_probe(struct i2c_client *i2c,
>  	if (ret < 0)
>  		goto err_i2c;
>  
> +	if (!palmas->wakeirq)
> +		goto no_wake_irq;
> +
> +	ret = devm_request_irq(palmas->dev, palmas->wakeirq,
> +			       palmas_wake_irq,
> +			       pdata->irq_flags,
> +			       dev_name(palmas->dev),
> +			       &palmas);
> +	if (ret < 0) {
> +		dev_err(palmas->dev, "Invalid wakeirq(%d) (res: %d), skiping\n",
> +			palmas->wakeirq, ret);
> +		palmas->wakeirq = 0;
> +	} else {
> +		/* We use wakeirq only during suspend-resume path */
> +		device_set_wakeup_capable(palmas->dev, true);
> +		disable_irq_nosync(palmas->wakeirq);
> +	}
> +
> +no_wake_irq:
>  no_irq:
>  	slave = PALMAS_BASE_TO_SLAVE(PALMAS_PU_PD_OD_BASE);
>  	addr = PALMAS_BASE_TO_REG(PALMAS_PU_PD_OD_BASE,
> @@ -706,6 +738,34 @@ static int palmas_i2c_remove(struct i2c_client *i2c)
>  	return 0;
>  }
>  
> +static int palmas_i2c_suspend(struct i2c_client *i2c,  pm_message_t mesg)
> +{
> +	struct palmas *palmas = i2c_get_clientdata(i2c);
> +	struct device *dev = &i2c->dev;
> +
> +	if (!palmas->wakeirq)
> +		return 0;
> +
> +	if (device_may_wakeup(dev))
> +		enable_irq(palmas->wakeirq);
> +
> +	return 0;
> +}
> +
> +static int palmas_i2c_resume(struct i2c_client *i2c)
> +{
> +	struct palmas *palmas = i2c_get_clientdata(i2c);
> +	struct device *dev = &i2c->dev;
> +
> +	if (!palmas->wakeirq)
> +		return 0;
> +
> +	if (device_may_wakeup(dev))
> +		disable_irq_nosync(palmas->wakeirq);
> +
> +	return 0;
> +}
> +
>  static const struct i2c_device_id palmas_i2c_id[] = {
>  	{ "palmas", },
>  	{ "twl6035", },
> @@ -721,6 +781,8 @@ static struct i2c_driver palmas_i2c_driver = {
>  		   .of_match_table = of_palmas_match_tbl,
>  		   .owner = THIS_MODULE,
>  	},
> +	.suspend = palmas_i2c_suspend,
> +	.resume = palmas_i2c_resume,
>  	.probe = palmas_i2c_probe,
>  	.remove = palmas_i2c_remove,
>  	.id_table = palmas_i2c_id,
> diff --git a/include/linux/mfd/palmas.h b/include/linux/mfd/palmas.h
> index fb0390a..e8cf4c2 100644
> --- a/include/linux/mfd/palmas.h
> +++ b/include/linux/mfd/palmas.h
> @@ -75,6 +75,7 @@ struct palmas {
>  	/* IRQ Data */
>  	int irq;
>  	u32 irq_mask;
> +	int wakeirq;
>  	struct mutex irq_lock;
>  	struct regmap_irq_chip_data *irq_data;
>  
> @@ -377,6 +378,7 @@ struct palmas_clk_platform_data {
>  
>  struct palmas_platform_data {
>  	int irq_flags;
> +	int wakeirq;
>  	int gpio_base;
>  
>  	/* bit value to be loaded to the POWER_CTRL register */
> 

-- 
Regards,
Nishanth Menon