[PATCH 1/2] mfd: s2mps11: Add manual shutdown method for Odroid XU3

[Anand Moon]

Hi Krzysztof,

On 3 August 2015 at 18:07, Krzysztof Kozlowski <k.kozlowski.k at gmail.com> wrote:
> On Odroid XU3 board (with S2MPS11 PMIC) the PWRHOLD bit in CTRL1
> register must be manually set to 0 before initiating power off sequence.
>
> One of usual power down methods for Exynos based devices looks like:
> 1. PWRHOLD pin of PMIC is connected to PSHOLD of Exynos.
> 2. Exynos holds up this pin during system operation.
> 3. ACOKB pin of PMIC is pulled up to VBATT and optionally to pin in
>    other device.
> 4. When PWRHOLD/PSHOLD goes low, the PMIC will turn off the power if
>    ACOKB goes high.
>
> On Odroid XU3 family the difference is in (3) - the ACOKB is grounded.
> This means that PMIC must manually set PWRHOLD field to low and then
> wait for signal from Application Processor (the usual change in
> PWRHOLD/PSHOLD pin will actually cut off the power).
>
> The patch adds respective binding allowing Odroid XU3 device to be
> powered off.
>
> Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k at gmail.com>
> Reported-by: Anand Moon <linux.amoon at gmail.com>
>
> ---
>
> Patch is losely based on patch in Hardkernel repository [0] and previous
> work of Anand Moon [1].
>
> [0] https://github.com/hardkernel/linux/commit/6897e62ba328bd1c8c095d918101863250cd73e7
> [1] http://www.spinics.net/lists/linux-samsung-soc/msg45959.html
> ---
>  Documentation/devicetree/bindings/mfd/s2mps11.txt |  4 +++
>  drivers/mfd/sec-core.c                            | 31 +++++++++++++++++++++++
>  include/linux/mfd/samsung/core.h                  |  2 ++
>  include/linux/mfd/samsung/s2mps11.h               |  1 +
>  4 files changed, 38 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mfd/s2mps11.txt b/Documentation/devicetree/bindings/mfd/s2mps11.txt
> index 57a045016fca..90eaef393325 100644
> --- a/Documentation/devicetree/bindings/mfd/s2mps11.txt
> +++ b/Documentation/devicetree/bindings/mfd/s2mps11.txt
> @@ -15,6 +15,10 @@ Optional properties:
>  - interrupt-parent: Specifies the phandle of the interrupt controller to which
>    the interrupts from s2mps11 are delivered to.
>  - interrupts: Interrupt specifiers for interrupt sources.
> +- samsung,s2mps11-acokb-ground: Indicates that ACOKB pin of S2MPS11 PMIC is
> +  connected to the ground so the PMIC must manually set PWRHOLD bit in CTRL1
> +  register to turn off the power. Usually the ACOKB is pulled up to VBATT so
> +  when PWRHOLD pin goes low, the rising ACOKB will trigger power off.
>
>  Optional nodes:
>  - clocks: s2mps11, s2mps13 and s5m8767 provide three(AP/CP/BT) buffered 32.768
> diff --git a/drivers/mfd/sec-core.c b/drivers/mfd/sec-core.c
> index d206a3e8fe87..a56ab2102a32 100644
> --- a/drivers/mfd/sec-core.c
> +++ b/drivers/mfd/sec-core.c
> @@ -278,6 +278,8 @@ static struct sec_platform_data *sec_pmic_i2c_parse_dt_pdata(
>          * not parsed here.
>          */
>
> +       pd->manual_poweroff = of_property_read_bool(dev->of_node,
> +                                               "samsung,s2mps11-acokb-ground");
>         return pd;
>  }
>  #else
> @@ -440,6 +442,34 @@ static int sec_pmic_remove(struct i2c_client *i2c)
>         return 0;
>  }
>
> +static void sec_pmic_shutdown(struct i2c_client *i2c)
> +{
> +       struct sec_pmic_dev *sec_pmic = i2c_get_clientdata(i2c);
> +       unsigned int reg, mask;
> +
> +       if (!sec_pmic->pdata->manual_poweroff)
> +               return;
> +
> +       switch (sec_pmic->device_type) {
> +       case S2MPS11X:
> +               reg = S2MPS11_REG_CTRL1;
> +               mask = S2MPS11_CTRL1_PWRHOLD_MASK;
> +               break;
> +       default:
> +               /*
> +                * Currently only one board with S2MPS11 needs this, so just
> +                * ignore the rest.
> +                */
> +               dev_warn(sec_pmic->dev,
> +                       "Unsupported device %lu for manual power off\n",
> +                       sec_pmic->device_type);
> +               return;
> +       }
> +
> +       regmap_update_bits(sec_pmic->regmap_pmic, reg, mask, 0);
> +}
> +
> +
>  #ifdef CONFIG_PM_SLEEP
>  static int sec_pmic_suspend(struct device *dev)
>  {
> @@ -491,6 +521,7 @@ static struct i2c_driver sec_pmic_driver = {
>         },
>         .probe = sec_pmic_probe,
>         .remove = sec_pmic_remove,
> +       .shutdown = sec_pmic_shutdown,
>         .id_table = sec_pmic_id,
>  };
>
> diff --git a/include/linux/mfd/samsung/core.h b/include/linux/mfd/samsung/core.h
> index 75115384f3fc..aa78957e092f 100644
> --- a/include/linux/mfd/samsung/core.h
> +++ b/include/linux/mfd/samsung/core.h
> @@ -132,6 +132,8 @@ struct sec_platform_data {
>         int                             buck2_init;
>         int                             buck3_init;
>         int                             buck4_init;
> +       /* Whether or not manually set PWRHOLD to low during shutdown. */
> +       bool                            manual_poweroff;
>  };
>
>  /**
> diff --git a/include/linux/mfd/samsung/s2mps11.h b/include/linux/mfd/samsung/s2mps11.h
> index 7981a9d77d3f..b288965e8101 100644
> --- a/include/linux/mfd/samsung/s2mps11.h
> +++ b/include/linux/mfd/samsung/s2mps11.h
> @@ -179,6 +179,7 @@ enum s2mps11_regulators {
>  #define S2MPS11_BUCK_N_VOLTAGES (S2MPS11_BUCK_VSEL_MASK + 1)
>  #define S2MPS11_RAMP_DELAY     25000           /* uV/us */
>
> +#define S2MPS11_CTRL1_PWRHOLD_MASK     BIT(4)
>
>  #define S2MPS11_BUCK2_RAMP_SHIFT       6
>  #define S2MPS11_BUCK34_RAMP_SHIFT      4
> --
> 2.1.4
>
Thanks. Tested on Odroid-XU3 board.

Tested-by: Anand Moon <linux.amoon at gmail.com>