[PATCH v3 2/3] regulator: mt6315: Add support for MT6315 regulator

Nicolas Boichat drinkcat at chromium.org
Wed Dec 23 19:38:44 EST 2020


On Wed, Dec 23, 2020 at 8:13 PM Hsin-Hsiung Wang
<hsin-hsiung.wang at mediatek.com> wrote:
>
> The MT6315 is a regulator found on boards based on MediaTek MT8192 and
> probably other SoCs. It connects as a slave to SoC using SPMI.
>
> Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang at mediatek.com>
> ---
>  drivers/regulator/Kconfig                  |  10 +
>  drivers/regulator/Makefile                 |   1 +
>  drivers/regulator/mt6315-regulator.c       | 298 +++++++++++++++++++++
>  include/linux/regulator/mt6315-regulator.h |  45 ++++
>  4 files changed, 354 insertions(+)
>  create mode 100644 drivers/regulator/mt6315-regulator.c
>  create mode 100644 include/linux/regulator/mt6315-regulator.h
>
> diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
> index 020a00d6696b..65612ba2734f 100644
> --- a/drivers/regulator/Kconfig
> +++ b/drivers/regulator/Kconfig
> @@ -703,6 +703,16 @@ config REGULATOR_MT6311
>           This driver supports the control of different power rails of device
>           through regulator interface.
>
> +config REGULATOR_MT6315
> +       tristate "MediaTek MT6315 PMIC"
> +       depends on SPMI
> +       select REGMAP_SPMI
> +       help
> +         Say y here to select this option to enable the power regulator of
> +         MediaTek MT6315 PMIC.
> +         This driver supports the control of different power rails of device
> +         through regulator interface.
> +
>  config REGULATOR_MT6323
>         tristate "MediaTek MT6323 PMIC"
>         depends on MFD_MT6397
> diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
> index 6ebae516258e..b2f47dd67112 100644
> --- a/drivers/regulator/Makefile
> +++ b/drivers/regulator/Makefile
> @@ -87,6 +87,7 @@ obj-$(CONFIG_REGULATOR_MP8859) += mp8859.o
>  obj-$(CONFIG_REGULATOR_MP886X) += mp886x.o
>  obj-$(CONFIG_REGULATOR_MPQ7920) += mpq7920.o
>  obj-$(CONFIG_REGULATOR_MT6311) += mt6311-regulator.o
> +obj-$(CONFIG_REGULATOR_MT6315) += mt6315-regulator.o
>  obj-$(CONFIG_REGULATOR_MT6323) += mt6323-regulator.o
>  obj-$(CONFIG_REGULATOR_MT6358) += mt6358-regulator.o
>  obj-$(CONFIG_REGULATOR_MT6360) += mt6360-regulator.o
> diff --git a/drivers/regulator/mt6315-regulator.c b/drivers/regulator/mt6315-regulator.c
> new file mode 100644
> index 000000000000..57ef628d48b4
> --- /dev/null
> +++ b/drivers/regulator/mt6315-regulator.c
> @@ -0,0 +1,298 @@
> +// SPDX-License-Identifier: GPL-2.0
> +//
> +// Copyright (c) 2020 MediaTek Inc.
> +
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>

Do you need this one? I don't see any IRQ-related function

> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/driver.h>
> +#include <linux/regulator/machine.h>
> +#include <linux/regulator/mt6315-regulator.h>
> +#include <linux/regulator/of_regulator.h>
> +#include <linux/spmi.h>
> +
> +#define MT6315_REG_WIDTH       8

Unused.

> +
> +#define MT6315_BUCK_MODE_AUTO          0
> +#define MT6315_BUCK_MODE_FORCE_PWM     1
> +#define MT6315_BUCK_MODE_LP            2
> +
> +struct mt6315_regulator_info {
> +       struct regulator_desc desc;
> +       u32 status_reg;
> +       u32 lp_mode_mask;
> +       u32 lp_mode_shift;
> +};
> +
> +struct mt_regulator_init_data {
> +       u32 slvid;
> +       u32 modeset_mask[MT6315_VBUCK_MAX];
> +};
> +
> +struct mt6315_chip {
> +       struct device *dev;
> +       struct regmap *regmap;
> +};
> +
> +#define MT_BUCK(_name, _bid, _vsel)                            \
> +[_bid] = {                                                     \
> +       .desc = {                                               \
> +               .name = _name,                                  \
> +               .of_match = of_match_ptr(_name),                \
> +               .regulators_node = "regulators",                \
> +               .ops = &mt6315_volt_range_ops,                  \
> +               .type = REGULATOR_VOLTAGE,                      \
> +               .id = _bid,                                     \
> +               .owner = THIS_MODULE,                           \
> +               .n_voltages = 0xbf,                             \
> +               .linear_ranges = mt_volt_range1,                \
> +               .n_linear_ranges = ARRAY_SIZE(mt_volt_range1),  \
> +               .vsel_reg = _vsel,                              \
> +               .vsel_mask = 0xff,                              \
> +               .enable_reg = MT6315_BUCK_TOP_CON0,             \
> +               .enable_mask = BIT(_bid),                       \
> +               .of_map_mode = mt6315_map_mode,                 \
> +       },                                                      \
> +       .status_reg = _bid##_DBG4,                                      \
> +       .lp_mode_mask = BIT(_bid),                              \
> +       .lp_mode_shift = _bid,                          \
> +}
> +
> +static const struct linear_range mt_volt_range1[] = {
> +       REGULATOR_LINEAR_RANGE(0, 0, 0xbf, 6250),
> +};
> +
> +static unsigned int mt6315_map_mode(u32 mode)
> +{
> +       switch (mode) {
> +       case MT6315_BUCK_MODE_AUTO:
> +               return REGULATOR_MODE_NORMAL;
> +       case MT6315_BUCK_MODE_FORCE_PWM:
> +               return REGULATOR_MODE_FAST;
> +       case MT6315_BUCK_MODE_LP:
> +               return REGULATOR_MODE_IDLE;
> +       default:
> +               return -EINVAL;
> +       }
> +}
> +
> +static unsigned int mt6315_regulator_get_mode(struct regulator_dev *rdev)
> +{
> +       struct mt_regulator_init_data *init = rdev_get_drvdata(rdev);
> +       const struct mt6315_regulator_info *info = (struct mt6315_regulator_info *)rdev->desc;

This is a little bit scary at first sight, please use container_of instead:

container_of(rdev->desc, struct mt6315_regulator_info, desc)

> +       int ret, regval;
> +       u32 modeset_mask;
> +
> +       modeset_mask = init->modeset_mask[rdev_get_id(rdev)];
> +       ret = regmap_read(rdev->regmap, MT6315_BUCK_TOP_4PHASE_ANA_CON42, &regval);
> +       if (ret != 0) {
> +               dev_notice(&rdev->dev, "Failed to get mode: %d\n", ret);
> +               return ret;
> +       }
> +
> +       if ((regval & modeset_mask) == modeset_mask)
> +               return REGULATOR_MODE_FAST;
> +
> +       ret = regmap_read(rdev->regmap, MT6315_BUCK_TOP_CON1, &regval);
> +       if (ret != 0) {
> +               dev_notice(&rdev->dev, "Failed to get lp mode: %d\n", ret);
> +               return ret;
> +       }
> +
> +       if (regval & info->lp_mode_mask)
> +               return REGULATOR_MODE_IDLE;
> +       else
> +               return REGULATOR_MODE_NORMAL;
> +}
> +
> +static int mt6315_regulator_set_mode(struct regulator_dev *rdev,
> +                                    u32 mode)
> +{
> +       struct mt_regulator_init_data *init = rdev_get_drvdata(rdev);
> +       const struct mt6315_regulator_info *info = (struct mt6315_regulator_info *)rdev->desc;

ditto (container_of)

> +       int ret, val, curr_mode;
> +       u32 modeset_mask;
> +
> +       modeset_mask = init->modeset_mask[rdev_get_id(rdev)];
> +       curr_mode = mt6315_regulator_get_mode(rdev);
> +       switch (mode) {
> +       case REGULATOR_MODE_FAST:

This seems to assume that you can't transition from
REGULATOR_MODE_IDLE to REGULATOR_MODE_FAST directly? Is that
guaranteed?

> +               ret = regmap_update_bits(rdev->regmap,
> +                                        MT6315_BUCK_TOP_4PHASE_ANA_CON42,
> +                                        modeset_mask,
> +                                        modeset_mask);
> +               break;
> +       case REGULATOR_MODE_NORMAL:
> +               if (curr_mode == REGULATOR_MODE_FAST) {
> +                       ret = regmap_update_bits(rdev->regmap,
> +                                                MT6315_BUCK_TOP_4PHASE_ANA_CON42,
> +                                                modeset_mask,
> +                                                0);
> +               } else if (curr_mode == REGULATOR_MODE_IDLE) {
> +                       ret = regmap_update_bits(rdev->regmap,
> +                                                MT6315_BUCK_TOP_CON1,
> +                                                info->lp_mode_mask,
> +                                                0);
> +                       usleep_range(100, 110);
> +               }
> +               break;
> +       case REGULATOR_MODE_IDLE:
> +               val = MT6315_BUCK_MODE_LP >> 1;
> +               val <<= info->lp_mode_shift;
> +               ret = regmap_update_bits(rdev->regmap,
> +                                        MT6315_BUCK_TOP_CON1,
> +                                        info->lp_mode_mask,
> +                                        val);
> +               break;
> +       default:
> +               ret = -EINVAL;
> +               dev_notice(&rdev->dev, "Not support (%d)\n", mode);

"Unsupported mode: %d\n"

> +               break;
> +       }
> +
> +       if (ret != 0) {
> +               dev_notice(&rdev->dev, "Failed to set mode: %d\n", ret);
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int mt6315_get_status(struct regulator_dev *rdev)
> +{
> +       const struct mt6315_regulator_info *info = (struct mt6315_regulator_info *)rdev->desc;

ditto (container_of)

> +       int ret;
> +       u32 regval;
> +
> +       ret = regmap_read(rdev->regmap, info->status_reg, &regval);
> +       if (ret < 0) {
> +               dev_notice(&rdev->dev, "Failed to get enable reg: %d\n", ret);
> +               return ret;
> +       }
> +
> +       return (regval & BIT(0)) ? REGULATOR_STATUS_ON : REGULATOR_STATUS_OFF;
> +}
> +
> +static const struct regulator_ops mt6315_volt_range_ops = {
> +       .list_voltage = regulator_list_voltage_linear_range,
> +       .map_voltage = regulator_map_voltage_linear_range,
> +       .set_voltage_sel = regulator_set_voltage_sel_regmap,
> +       .get_voltage_sel = regulator_get_voltage_sel_regmap,
> +       .set_voltage_time_sel = regulator_set_voltage_time_sel,
> +       .enable = regulator_enable_regmap,
> +       .disable = regulator_disable_regmap,
> +       .is_enabled = regulator_is_enabled_regmap,
> +       .get_status = mt6315_get_status,
> +       .set_mode = mt6315_regulator_set_mode,
> +       .get_mode = mt6315_regulator_get_mode,
> +};
> +
> +static const struct mt6315_regulator_info mt6315_regulators[MT6315_VBUCK_MAX] = {
> +       MT_BUCK("vbuck1", MT6315_VBUCK1, MT6315_BUCK_TOP_ELR0),
> +       MT_BUCK("vbuck2", MT6315_VBUCK2, MT6315_BUCK_TOP_ELR2),
> +       MT_BUCK("vbuck3", MT6315_VBUCK3, MT6315_BUCK_TOP_ELR4),
> +       MT_BUCK("vbuck4", MT6315_VBUCK4, MT6315_BUCK_TOP_ELR6),
> +};
> +
> +static const struct regmap_config mt6315_regmap_config = {
> +       .reg_bits       = 16,
> +       .val_bits       = 8,
> +       .max_register   = 0x16d0,
> +       .fast_io        = true,
> +};
> +
> +static const struct of_device_id mt6315_of_match[] = {
> +       {
> +               .compatible = "mediatek,mt6315-regulator",
> +       }, {
> +               /* sentinel */
> +       },
> +};
> +MODULE_DEVICE_TABLE(of, mt6315_of_match);
> +
> +static int mt6315_regulator_probe(struct spmi_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct regmap *regmap;
> +       struct mt6315_chip *chip;
> +       struct mt_regulator_init_data *init_data;
> +       struct regulator_config config = {};
> +       struct regulator_dev *rdev;
> +       int i;
> +
> +       regmap = devm_regmap_init_spmi_ext(pdev, &mt6315_regmap_config);
> +       if (!regmap)
> +               return -ENODEV;
> +
> +       chip = devm_kzalloc(dev, sizeof(struct mt6315_chip), GFP_KERNEL);
> +       if (!chip)
> +               return -ENOMEM;
> +
> +       init_data = devm_kzalloc(dev, sizeof(struct mt_regulator_init_data), GFP_KERNEL);
> +       if (!init_data)
> +               return -ENOMEM;
> +
> +       chip->dev = dev;
> +       chip->regmap = regmap;
> +       dev_set_drvdata(dev, chip);
> +
> +       config.dev = dev;
> +       config.regmap = regmap;
> +       for (i = MT6315_VBUCK1; i < MT6315_VBUCK_MAX; i++) {
> +               init_data->modeset_mask[i] = 1 << (i - 1);

BIT(i-1)

But, wait, MT6315_VBUCK1 is 0 right? Should this just be 1 << i ==> BIT(i) ?

> +               config.driver_data = init_data;
> +               rdev = devm_regulator_register(dev, &mt6315_regulators[i].desc, &config);

This also initializes the regulators 2,4 on MT6315_CPU, is that ok?
I'd assume we'd not want to initialize those linked regulators (and
that's what your previous change did)

> +               if (IS_ERR(rdev)) {
> +                       dev_notice(dev, "Failed to register %s\n", mt6315_regulators[i].desc.name);
> +                       continue;
> +               }

It feels incorrect to call devm_regulator_register before modeset_mask
has been set properly...

2 options:
1. Fold the logic below into this loop.
2. Something like this:

switch (init_data->slvid) {
  init_data->modeset_mask[MT6315_VBUCK1] = 0x3, 0xB, or default 0x1;
}
for (i = MT6315_VBUCK2; i < MT6315_VBUCK_MAX; i++)
  init_data->modeset_mask[i] = 1 << i;
for (i = MT6315_VBUCK1; i < MT6315_VBUCK_MAX; i++) {
  devm_regulator_register()
}

> +       }
> +
> +       init_data->slvid = pdev->usid;
> +       switch (init_data->slvid) {

Just use pdev->usid directly here? (you don't use init_data->slvid
anywhere else so it doesn't seem useful to copy it)

> +       case MT6315_CPU:
> +               init_data->modeset_mask[MT6315_VBUCK1] = 0xB;

I'd almost prefer seeing BIT(MT6315_VBUCK1) | BIT(MT6315_VBUCK2) |
BIT(MT6315_VBUCK4)
(or maybe add a small comment above this line to explain that 1,2,4
are combined)

> +               break;
> +       case MT6315_GPU:
> +       case MT6315_MD:
> +               init_data->modeset_mask[MT6315_VBUCK1] = 0x3;
> +               break;
> +       default:
> +               break;
> +       }

Oh, I see, so you got rid of the device tree property
`mtk,combined-regulator` and instead match the USID (it would have
been great to document that clearly in your changelog).

I think this is ok as long as all MT6315 part numbers have a different
USID, but please see my comment below.

> +
> +       return 0;
> +}
> +
> +static void mt6315_regulator_shutdown(struct spmi_device *pdev)
> +{
> +       struct mt6315_chip *chip = dev_get_drvdata(&pdev->dev);
> +       int ret = 0;
> +
> +       ret |= regmap_write(chip->regmap, MT6315_TOP_TMA_KEY_H, PROTECTION_KEY_H);
> +       ret |= regmap_write(chip->regmap, MT6315_TOP_TMA_KEY, PROTECTION_KEY);
> +       ret |= regmap_update_bits(chip->regmap, MT6315_TOP2_ELR7, 1, 1);
> +       ret |= regmap_write(chip->regmap, MT6315_TOP_TMA_KEY, 0);
> +       ret |= regmap_write(chip->regmap, MT6315_TOP_TMA_KEY_H, 0);
> +       if (ret < 0)
> +               dev_notice(&pdev->dev, "[%#x] Failed to enable power off sequence. %d\n",
> +                          pdev->usid, ret);
> +}
> +
> +static struct spmi_driver mt6315_regulator_driver = {
> +       .driver         = {
> +               .name   = "mt6315-regulator",
> +               .of_match_table = mt6315_of_match,
> +       },
> +       .probe = mt6315_regulator_probe,
> +       .shutdown = mt6315_regulator_shutdown,
> +};
> +
> +module_spmi_driver(mt6315_regulator_driver);
> +
> +MODULE_AUTHOR("Hsin-Hsiung Wang <hsin-hsiung.wang at mediatek.com>");
> +MODULE_DESCRIPTION("Regulator Driver for MediaTek MT6315 PMIC");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/regulator/mt6315-regulator.h b/include/linux/regulator/mt6315-regulator.h
> new file mode 100644
> index 000000000000..38bf365de24d
> --- /dev/null
> +++ b/include/linux/regulator/mt6315-regulator.h
> @@ -0,0 +1,45 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2020 MediaTek Inc.
> + */
> +
> +#ifndef __LINUX_REGULATOR_MT6315_H
> +#define __LINUX_REGULATOR_MT6315_H
> +
> +#define MT6315_MD      3
> +#define MT6315_CPU     6
> +#define MT6315_GPU     7

MD/CPU/GPU is the application, can we use the part numbers instead?

And actually there seem to be 2 MT6315 that could be used for GPU: QP
or SP, so "GPU" could be confusing later on if you added support for
QP.

Does each 5 MT6315 use a unique USID? (PP, QP, RP, SP, TP?)

If so, can we use the following instead?

#define MT6315_XX 3 // The datasheet I have doesn't specify USID for
the part numbers, so I'm not clear if this is RP or TP.
#define MT6315_PP 6
#define MT6315_SP 7


> +
> +enum {
> +       MT6315_VBUCK1 = 0,
> +       MT6315_VBUCK2,
> +       MT6315_VBUCK3,
> +       MT6315_VBUCK4,
> +       MT6315_VBUCK_MAX,
> +};
> +
> +/* Register */
> +#define MT6315_SWCID_H                         0xC
> +#define MT6315_TOP2_ELR7                       0x139
> +#define MT6315_TOP_TMA_KEY                     0x39F
> +#define MT6315_TOP_TMA_KEY_H                   0x3A0
> +#define MT6315_BUCK_TOP_CON0                   0x1440
> +#define MT6315_BUCK_TOP_CON1                   0x1443
> +#define MT6315_BUCK_TOP_ELR0                   0x1449
> +#define MT6315_BUCK_TOP_ELR2                   0x144B
> +#define MT6315_BUCK_TOP_ELR4                   0x144D
> +#define MT6315_BUCK_TOP_ELR6                   0x144F
> +#define MT6315_VBUCK1_DBG0                     0x1499
> +#define MT6315_VBUCK1_DBG4                     0x149D
> +#define MT6315_VBUCK2_DBG0                     0x1519
> +#define MT6315_VBUCK2_DBG4                     0x151D
> +#define MT6315_VBUCK3_DBG0                     0x1599
> +#define MT6315_VBUCK3_DBG4                     0x159D
> +#define MT6315_VBUCK4_DBG0                     0x1619
> +#define MT6315_VBUCK4_DBG4                     0x161D
> +#define MT6315_BUCK_TOP_4PHASE_ANA_CON42       0x16B1
> +
> +#define PROTECTION_KEY_H                       0x9C
> +#define PROTECTION_KEY                         0xEA
> +
> +#endif /* __LINUX_REGULATOR_MT6315_H */
> --
> 2.18.0
>



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