linux-kernel - Re: [PATCH 1/1] mfd: rk808: Prepare rk805 for poweroff

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Message-ID: <489e70a8-dbe7-e248-972e-c7de4e0f2c1a@gmail.com>
Date:   Wed, 9 Jan 2019 15:10:34 +0200
From:   Stefan Mavrodiev <stefan.mavrodiev@...il.com>
To:     Heiko Stübner <heiko@...ech.de>,
        Stefan Mavrodiev <stefan@...mex.com>
Cc:     linux-rockchip@...ts.infradead.org,
        Lee Jones <lee.jones@...aro.org>,
        open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/1] mfd: rk808: Prepare rk805 for poweroff


On 1/9/19 3:07 PM, Heiko Stübner wrote:
> Hi Stefan, Lee,
>
> Am Dienstag, 2. Oktober 2018, 09:38:29 CET schrieb Stefan Mavrodiev:
>> RK805 has SLEEP signal, which can put the device into SLEEP or OFF
>> mode. The default is SLEEP mode.
>>
>> However, when the kernel performs power-off (actually the ATF) the
>> device will not go fully off and this will result in higher power
>> consumption and inability to wake the device with RTC alarm.
>>
>> The solution is to enable pm_power_off_prepare function, which will
>> configure SLEEP pin for OFF function.
>>
>> Signed-off-by: Stefan Mavrodiev <stefan@...mex.com>
> just found this while cleaning my inbox and this change looks
> significant and it seems hasn't been applied yet.
>
> I guess this is still relevant, right?

Yes, but I guess it's out-of-sync with the latest kernel.

>
>
> Heiko
>
>> ---
>>   drivers/mfd/rk808.c | 24 ++++++++++++++++++++++++
>>   1 file changed, 24 insertions(+)
>>
>> diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
>> index 216fbf6..50f3f78 100644
>> --- a/drivers/mfd/rk808.c
>> +++ b/drivers/mfd/rk808.c
>> @@ -387,6 +387,25 @@ static void rk805_device_shutdown(void)
>>   		dev_err(&rk808_i2c_client->dev, "power off error!\n");
>>   }
>>
>> +static void rk805_device_shutdown_prepare(void)
>> +{
>> +	int ret;
>> +	struct rk808 *rk808 = i2c_get_clientdata(rk808_i2c_client);
>> +
>> +	if (!rk808) {
>> +		dev_warn(&rk808_i2c_client->dev,
>> +			 "have no rk805, so do nothing here\n");
>> +
>> +		return;
>> +	}
>> +
>> +	ret = regmap_update_bits(rk808->regmap,
>> +				 RK805_GPIO_IO_POL_REG,
>> +				 SLP_SD_MSK, SHUTDOWN_FUN);
>> +	if (ret)
>> +		dev_err(&rk808_i2c_client->dev, "power off error!\n");
>> +}
>> +
>>   static void rk808_device_shutdown(void)
>>   {
>>   	int ret;
>> @@ -549,6 +568,10 @@ static int rk808_probe(struct i2c_client *client,
>>   	if (pm_off && !pm_power_off) {
>>   		rk808_i2c_client = client;
>>   		pm_power_off = pm_pwroff_fn;
>> +	} else if (pm_off && !pm_power_off_prepare &&
>> +		   rk808->variant == RK805_ID) {
>> +		rk808_i2c_client = client;
>> +		pm_power_off_prepare = rk805_device_shutdown_prepare;
>>   	}
>>
>>   	return 0;
>> @@ -564,6 +587,7 @@ static int rk808_remove(struct i2c_client *client)
>>
>>   	regmap_del_irq_chip(client->irq, rk808->irq_data);
>>   	pm_power_off = NULL;
>> +	pm_power_off_prepare = NULL;
>>
>>   	return 0;
>>   }
>
>
>