Re: [PATCH v2] Input: pmic8xxx-pwrkey - Support shutdown

From: Dmitry Torokhov
Date: Mon Jul 13 2015 - 20:25:18 EST

Hi Stephen,

On Mon, Jul 13, 2015 at 04:30:34PM -0700, Stephen Boyd wrote:
> On pm8xxx PMICs, shutdown and restart are signaled to the PMIC
> via a pin called PS_HOLD. When this pin goes low, the PMIC
> performs a configurable power sequence. Add a .shutdown hook so
> that we can properly configure this power sequence for shutdown
> or restart depending on the system state.

Just a bit of bikeshedding on my part...

>
> Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> ---
> drivers/input/misc/pmic8xxx-pwrkey.c | 284 ++++++++++++++++++++++++++++++++++-
> 1 file changed, 277 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c
> index c4ca20e63221..1d1ee5951b3a 100644
> --- a/drivers/input/misc/pmic8xxx-pwrkey.c
> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c
> @@ -20,17 +20,72 @@
> #include <linux/regmap.h>
> #include <linux/log2.h>
> #include <linux/of.h>
> +#include <linux/of_device.h>
>
> #define PON_CNTL_1 0x1C
> #define PON_CNTL_PULL_UP BIT(7)
> #define PON_CNTL_TRIG_DELAY_MASK (0x7)
> +#define PON_CNTL_1_PULL_UP_EN 0xe0
> +#define PON_CNTL_1_USB_PWR_EN 0x10
> +#define PON_CNTL_1_WD_EN_RESET 0x08
> +
> +#define PM8058_SLEEP_CTRL 0x02b
> +#define PM8921_SLEEP_CTRL 0x10a
> +
> +#define SLEEP_CTRL_SMPL_EN_RESET 0x04
> +
> +/* Regulator master enable addresses */
> +#define REG_PM8058_VREG_EN_MSM 0x018
> +#define REG_PM8058_VREG_EN_GRP_5_4 0x1C8
> +
> +/* Regulator control registers for shutdown/reset */
> +#define PM8058_S0_CTRL 0x004
> +#define PM8058_S1_CTRL 0x005
> +#define PM8058_S3_CTRL 0x111
> +#define PM8058_L21_CTRL 0x120
> +#define PM8058_L22_CTRL 0x121
> +
> +#define PM8058_REGULATOR_ENABLE_MASK 0x80
> +#define PM8058_REGULATOR_ENABLE 0x80
> +#define PM8058_REGULATOR_DISABLE 0x00
> +#define PM8058_REGULATOR_PULL_DOWN_MASK 0x40
> +#define PM8058_REGULATOR_PULL_DOWN_EN 0x40
> +
> +/* Buck CTRL register */
> +#define PM8058_SMPS_LEGACY_VREF_SEL 0x20
> +#define PM8058_SMPS_LEGACY_VPROG_MASK 0x1F
> +#define PM8058_SMPS_ADVANCED_BAND_MASK 0xC0
> +#define PM8058_SMPS_ADVANCED_BAND_SHIFT 6
> +#define PM8058_SMPS_ADVANCED_VPROG_MASK 0x3F
> +
> +/* Buck TEST2 registers for shutdown/reset */
> +#define PM8058_S0_TEST2 0x084
> +#define PM8058_S1_TEST2 0x085
> +#define PM8058_S3_TEST2 0x11A
> +
> +#define PM8058_REGULATOR_BANK_WRITE 0x80
> +#define PM8058_REGULATOR_BANK_MASK 0x70
> +#define PM8058_REGULATOR_BANK_SHIFT 4
> +#define PM8058_REGULATOR_BANK_SEL(n) ((n) << PM8058_REGULATOR_BANK_SHIFT)
> +
> +/* Buck TEST2 register bank 1 */
> +#define PM8058_SMPS_LEGACY_VLOW_SEL 0x01
> +
> +/* Buck TEST2 register bank 7 */
> +#define PM8058_SMPS_ADVANCED_MODE_MASK 0x02
> +#define PM8058_SMPS_ADVANCED_MODE 0x02
> +#define PM8058_SMPS_LEGACY_MODE 0x00
>
> /**
> * struct pmic8xxx_pwrkey - pmic8xxx pwrkey information
> * @key_press_irq: key press irq number
> + * @regmap: device regmap
> + * @shutdown_fn: shutdown configuration function
> */
> struct pmic8xxx_pwrkey {
> int key_press_irq;
> + struct regmap *regmap;
> + int (*shutdown_fn)(struct pmic8xxx_pwrkey *, bool);
> };
>
> static irqreturn_t pwrkey_press_irq(int irq, void *_pwr)
> @@ -76,6 +131,220 @@ static int __maybe_unused pmic8xxx_pwrkey_resume(struct device *dev)
> static SIMPLE_DEV_PM_OPS(pm8xxx_pwr_key_pm_ops,
> pmic8xxx_pwrkey_suspend, pmic8xxx_pwrkey_resume);
>
> +static void pmic8xxx_pwrkey_shutdown(struct platform_device *pdev)
> +{
> + struct pmic8xxx_pwrkey *pwrkey = platform_get_drvdata(pdev);
> + int ret;
> + u8 mask, val;
> + bool reset = system_state == SYSTEM_RESTART;
> +
> + if (pwrkey->shutdown_fn) {
> + ret = pwrkey->shutdown_fn(pwrkey, reset);
> + if (ret)
> + return;

Can we call this variable "error" please?

> + }
> +
> + /*
> + * Select action to perform (reset or shutdown) when PS_HOLD goes low.
> + * Also ensure that KPD, CBL0, and CBL1 pull ups are enabled and that
> + * USB charging is enabled.
> + */
> + mask = PON_CNTL_1_PULL_UP_EN | PON_CNTL_1_USB_PWR_EN;
> + mask |= PON_CNTL_1_WD_EN_RESET;
> + val = mask;
> + if (!reset)
> + val &= ~PON_CNTL_1_WD_EN_RESET;
> +
> + regmap_update_bits(pwrkey->regmap, PON_CNTL_1, mask, val);
> +}
> +
> +/*
> + * Set an SMPS regulator to be disabled in its CTRL register, but enabled
> + * in the master enable register. Also set it's pull down enable bit.
> + * Take care to make sure that the output voltage doesn't change if switching
> + * from advanced mode to legacy mode.
> + */
> +static int pm8058_disable_smps_locally_set_pull_down(struct regmap *regmap,
> + u16 ctrl_addr, u16 test2_addr, u16 master_enable_addr,
> + u8 master_enable_bit)
> +{
> + int ret = 0;

Why does it need to be initialized? And "error" too please.

> + u8 vref_sel, vlow_sel, band, vprog, bank;
> + unsigned int reg;
> +
> + bank = PM8058_REGULATOR_BANK_SEL(7);
> + ret = regmap_write(regmap, test2_addr, bank);
> + if (ret)
> + return ret;
> +
> + ret = regmap_read(regmap, test2_addr, &reg);
> + if (ret)
> + return ret;
> +
> + reg &= PM8058_SMPS_ADVANCED_MODE_MASK;
> + /* Check if in advanced mode. */
> + if (reg == PM8058_SMPS_ADVANCED_MODE) {
> + /* Determine current output voltage. */
> + ret = regmap_read(regmap, ctrl_addr, &reg);
> + if (ret)
> + return ret;
> +
> + band = reg & PM8058_SMPS_ADVANCED_BAND_MASK;
> + band >>= PM8058_SMPS_ADVANCED_BAND_SHIFT;
> + switch (band) {
> + case 3:
> + vref_sel = 0;
> + vlow_sel = 0;
> + break;
> + case 2:
> + vref_sel = PM8058_SMPS_LEGACY_VREF_SEL;
> + vlow_sel = 0;
> + break;
> + case 1:
> + vref_sel = PM8058_SMPS_LEGACY_VREF_SEL;
> + vlow_sel = PM8058_SMPS_LEGACY_VLOW_SEL;
> + break;
> + default:
> + pr_err("%s: regulator already disabled\n", __func__);
> + return -EPERM;
> + }
> + vprog = reg & PM8058_SMPS_ADVANCED_VPROG_MASK;
> + /* Round up if fine step is in use. */
> + vprog = (vprog + 1) >> 1;
> + if (vprog > PM8058_SMPS_LEGACY_VPROG_MASK)
> + vprog = PM8058_SMPS_LEGACY_VPROG_MASK;
> +
> + /* Set VLOW_SEL bit. */
> + bank = PM8058_REGULATOR_BANK_SEL(1);
> + ret = regmap_write(regmap, test2_addr, bank);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(regmap, test2_addr,
> + PM8058_REGULATOR_BANK_WRITE | PM8058_REGULATOR_BANK_MASK
> + | PM8058_SMPS_LEGACY_VLOW_SEL,
> + PM8058_REGULATOR_BANK_WRITE |
> + PM8058_REGULATOR_BANK_SEL(1) | vlow_sel);
> + if (ret)
> + return ret;
> +
> + /* Switch to legacy mode */
> + bank = PM8058_REGULATOR_BANK_SEL(7);
> + ret = regmap_write(regmap, test2_addr, bank);
> + if (ret)
> + return ret;
> +
> + ret = regmap_update_bits(regmap, test2_addr,
> + PM8058_REGULATOR_BANK_WRITE |
> + PM8058_REGULATOR_BANK_MASK |
> + PM8058_SMPS_ADVANCED_MODE_MASK,
> + PM8058_REGULATOR_BANK_WRITE |
> + PM8058_REGULATOR_BANK_SEL(7) |
> + PM8058_SMPS_LEGACY_MODE);
> + if (ret)
> + return ret;
> +
> + /* Enable locally, enable pull down, keep voltage the same. */
> + ret = regmap_update_bits(regmap, ctrl_addr,
> + PM8058_REGULATOR_ENABLE_MASK |
> + PM8058_REGULATOR_PULL_DOWN_MASK |
> + PM8058_SMPS_LEGACY_VREF_SEL |
> + PM8058_SMPS_LEGACY_VPROG_MASK,
> + PM8058_REGULATOR_ENABLE | PM8058_REGULATOR_PULL_DOWN_EN
> + | vref_sel | vprog);
> + if (ret)
> + return ret;
> + }
> +
> + /* Enable in master control register. */
> + ret = regmap_update_bits(regmap, master_enable_addr,
> + master_enable_bit, master_enable_bit);
> + if (ret)
> + return ret;
> +
> + /* Disable locally and enable pull down. */
> + return regmap_update_bits(regmap, ctrl_addr,
> + PM8058_REGULATOR_ENABLE_MASK | PM8058_REGULATOR_PULL_DOWN_MASK,
> + PM8058_REGULATOR_DISABLE | PM8058_REGULATOR_PULL_DOWN_EN);
> +}
> +
> +static int pm8058_disable_ldo_locally_set_pull_down(struct regmap *regmap,
> + u16 ctrl_addr, u16 master_enable_addr, u8 master_enable_bit)
> +{
> + int ret;

Here too.

> +
> + /* Enable LDO in master control register. */
> + ret = regmap_update_bits(regmap, master_enable_addr,
> + master_enable_bit, master_enable_bit);
> + if (ret)
> + return ret;
> +
> + /* Disable LDO in CTRL register and set pull down */
> + return regmap_update_bits(regmap, ctrl_addr,
> + PM8058_REGULATOR_ENABLE_MASK | PM8058_REGULATOR_PULL_DOWN_MASK,
> + PM8058_REGULATOR_DISABLE | PM8058_REGULATOR_PULL_DOWN_EN);
> +}
> +
> +static int pm8058_pwrkey_shutdown(struct pmic8xxx_pwrkey *pwrkey, bool reset)
> +{
> + int ret;

And here.

> + struct regmap *regmap = pwrkey->regmap;
> + u8 mask, val;
> +
> + /* When shutting down, enable active pulldowns on important rails. */
> + if (!reset) {
> + /* Disable SMPS's 0,1,3 locally and set pulldown enable bits. */
> + pm8058_disable_smps_locally_set_pull_down(regmap,
> + PM8058_S0_CTRL, PM8058_S0_TEST2,
> + REG_PM8058_VREG_EN_MSM, BIT(7));
> + pm8058_disable_smps_locally_set_pull_down(regmap,
> + PM8058_S1_CTRL, PM8058_S1_TEST2,
> + REG_PM8058_VREG_EN_MSM, BIT(6));
> + pm8058_disable_smps_locally_set_pull_down(regmap,
> + PM8058_S3_CTRL, PM8058_S3_TEST2,
> + REG_PM8058_VREG_EN_GRP_5_4, BIT(7) | BIT(4));
> + /* Disable LDO 21 locally and set pulldown enable bit. */
> + pm8058_disable_ldo_locally_set_pull_down(regmap,
> + PM8058_L21_CTRL, REG_PM8058_VREG_EN_GRP_5_4,
> + BIT(1));
> + }
> +
> + /*
> + * Fix-up: Set regulator LDO22 to 1.225 V in high power mode. Leave its
> + * pull-down state intact. This ensures a safe shutdown.
> + */
> + ret = regmap_update_bits(regmap, PM8058_L22_CTRL, 0xbf, 0x93);
> + if (ret)
> + return ret;
> +
> + /* Enable SMPL if resetting is desired */
> + mask = SLEEP_CTRL_SMPL_EN_RESET;
> + val = 0;
> + if (reset)
> + val = mask;
> + return regmap_update_bits(regmap, PM8058_SLEEP_CTRL, mask, val);
> +

Stray empty line.

> +}
> +
> +static int pm8921_pwrkey_shutdown(struct pmic8xxx_pwrkey *pwrkey, bool reset)
> +{
> + struct regmap *regmap = pwrkey->regmap;
> + u8 mask = SLEEP_CTRL_SMPL_EN_RESET;
> + u8 val = 0;
> +
> + /* Enable SMPL if resetting is desired */
> + if (reset)
> + val = mask;
> + return regmap_update_bits(regmap, PM8921_SLEEP_CTRL, mask, val);
> +}
> +
> +static const struct of_device_id pm8xxx_pwr_key_id_table[] = {
> + { .compatible = "qcom,pm8058-pwrkey", .data = &pm8058_pwrkey_shutdown },
> + { .compatible = "qcom,pm8921-pwrkey", .data = &pm8921_pwrkey_shutdown },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, pm8xxx_pwr_key_id_table);
> +

Can we please keep IDs and device table where it was, close to the
driver definition?

> static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> {
> struct input_dev *pwr;
> @@ -88,6 +357,11 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> struct pmic8xxx_pwrkey *pwrkey;
> u32 kpd_delay;
> bool pull_up;
> + const struct of_device_id *match;
> +
> + match = of_match_device(pm8xxx_pwr_key_id_table, &pdev->dev);
> + if (!match)
> + return -ENODEV;
>
> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay))
> kpd_delay = 15625;
> @@ -109,6 +383,8 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev)
> if (!pwrkey)
> return -ENOMEM;
>
> + pwrkey->shutdown_fn = match->data;
> + pwrkey->regmap = regmap;
> pwrkey->key_press_irq = key_press_irq;
>
> pwr = devm_input_allocate_device(&pdev->dev);
> @@ -181,16 +457,10 @@ static int pmic8xxx_pwrkey_remove(struct platform_device *pdev)
> return 0;
> }
>
> -static const struct of_device_id pm8xxx_pwr_key_id_table[] = {
> - { .compatible = "qcom,pm8058-pwrkey" },
> - { .compatible = "qcom,pm8921-pwrkey" },
> - { }
> -};
> -MODULE_DEVICE_TABLE(of, pm8xxx_pwr_key_id_table);
> -
> static struct platform_driver pmic8xxx_pwrkey_driver = {
> .probe = pmic8xxx_pwrkey_probe,
> .remove = pmic8xxx_pwrkey_remove,
> + .shutdown = pmic8xxx_pwrkey_shutdown,
> .driver = {
> .name = "pm8xxx-pwrkey",
> .pm = &pm8xxx_pwr_key_pm_ops,
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>

Thanks.

--
Dmitry
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