On Tue, 21 May 2019, Stefan Mavrodiev wrote:
> 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 <ste...@olimex.com>
> ---
> Changes for v2:
> - Move pm_pwroff_prep_fn to header
> - Check pm_power_off_prepare before make it NULL
>
> drivers/mfd/rk808.c | 29 +++++++++++++++++++++++++++++
> include/linux/mfd/rk808.h | 1 +
> 2 files changed, 30 insertions(+)
>
> diff --git a/drivers/mfd/rk808.c b/drivers/mfd/rk808.c
> index c0b179792bbf..fb6cdf900899 100644
> --- a/drivers/mfd/rk808.c
> +++ b/drivers/mfd/rk808.c
> @@ -387,6 +387,24 @@ 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");
No need for this message I think.
If it's not available, just return.
> + 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");
> +}
"Failed to shutdown device"
> static void rk808_device_shutdown(void)
> {
> int ret;
> @@ -475,6 +493,7 @@ static int rk808_probe(struct i2c_client *client,
> cells = rk805s;
> nr_cells = ARRAY_SIZE(rk805s);
> rk808->pm_pwroff_fn = rk805_device_shutdown;
> + rk808->pm_pwroff_prep_fn = rk805_device_shutdown_prepare;
> break;
> case RK808_ID:
> rk808->regmap_cfg = &rk808_regmap_config;
> @@ -550,6 +569,12 @@ static int rk808_probe(struct i2c_client *client,
> pm_power_off = rk808->pm_pwroff_fn;
> }
>
> + if (pm_off && !pm_power_off_prepare) {
> + if (!rk808_i2c_client)
> + rk808_i2c_client = client;
> + pm_power_off_prepare = rk808->pm_pwroff_prep_fn;
> + }
> +
> return 0;
>
> err_irq:
> @@ -566,6 +591,10 @@ static int rk808_remove(struct i2c_client *client)
> if (rk808->pm_pwroff_fn && pm_power_off == rk808->pm_pwroff_fn)
> pm_power_off = NULL;
>
> + if (rk808->pm_pwroff_prep_fn &&
> + pm_power_off_prepare == rk808->pm_pwroff_prep_fn)
> + pm_power_off_prepare = NULL;
I think this block would benefit from a comment.
> return 0;
> }
>
> diff --git a/include/linux/mfd/rk808.h b/include/linux/mfd/rk808.h
> index 8b5d68a7bb9c..ec928173e507 100644
> --- a/include/linux/mfd/rk808.h
> +++ b/include/linux/mfd/rk808.h
> @@ -454,5 +454,6 @@ struct rk808 {
> const struct regmap_config *regmap_cfg;
> const struct regmap_irq_chip *regmap_irq_chip;
> void (*pm_pwroff_fn)(void);
> + void (*pm_pwroff_prep_fn)(void);
> };
> #endif /* __LINUX_REGULATOR_RK808_H */
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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