2024-02-16 23:17:41

by Dmitry Baryshkov

[permalink] [raw]
Subject: Re: [PATCH v5 16/18] power: pwrseq: add a driver for the QCA6390 PMU module

On Fri, 16 Feb 2024 at 22:33, Bartosz Golaszewski <[email protected]> wrote:
>
> From: Bartosz Golaszewski <[email protected]>
>
> This adds the power sequencing driver for the QCA6390's PMU module. It
> uses the pwrseq subsystem and knows how to match the sequencer to the
> consumer device by verifying the relevant properties and DT layout.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> ---
> drivers/power/sequencing/Kconfig | 16 +
> drivers/power/sequencing/Makefile | 2 +
> drivers/power/sequencing/pwrseq-qca6390.c | 353 ++++++++++++++++++++++
> 3 files changed, 371 insertions(+)
> create mode 100644 drivers/power/sequencing/pwrseq-qca6390.c
>
> diff --git a/drivers/power/sequencing/Kconfig b/drivers/power/sequencing/Kconfig
> index ba5732b1dbf8..84ddf3b4ae56 100644
> --- a/drivers/power/sequencing/Kconfig
> +++ b/drivers/power/sequencing/Kconfig
> @@ -10,3 +10,19 @@ menuconfig POWER_SEQUENCING
> during power-up.
>
> If unsure, say no.
> +
> +if POWER_SEQUENCING
> +
> +config POWER_SEQUENCING_QCA6390
> + tristate "QCA6390 PMU driver"
> + default m if ARCH_QCOM
> + help
> + Say U here to enable the power sequencing driver for Qualcomm
> + QCA6390.
> +
> + The QCA6390 package contains the BT and WLAN modules whose power
> + is controlled by the PMU module. As the former two share the power-up
> + sequence which is executed by the PMU, this driver is needed for
> + correct power control.
> +
> +endif
> diff --git a/drivers/power/sequencing/Makefile b/drivers/power/sequencing/Makefile
> index dcdf8c0c159e..628345c4e7ae 100644
> --- a/drivers/power/sequencing/Makefile
> +++ b/drivers/power/sequencing/Makefile
> @@ -2,3 +2,5 @@
>
> obj-$(CONFIG_POWER_SEQUENCING) += pwrseq-core.o
> pwrseq-core-y := core.o
> +
> +obj-$(CONFIG_POWER_SEQUENCING_QCA6390) += pwrseq-qca6390.o
> diff --git a/drivers/power/sequencing/pwrseq-qca6390.c b/drivers/power/sequencing/pwrseq-qca6390.c
> new file mode 100644
> index 000000000000..5f254f9c71d7
> --- /dev/null
> +++ b/drivers/power/sequencing/pwrseq-qca6390.c
> @@ -0,0 +1,353 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2024 Linaro Ltd.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/jiffies.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/pwrseq/provider.h>
> +#include <linux/string.h>
> +#include <linux/types.h>
> +
> +struct pwrseq_qca6390_vreg {
> + const char *name;
> + unsigned int load_uA;
> +};
> +
> +struct pwrseq_qca6390_pdata {
> + const struct pwrseq_qca6390_vreg *vregs_common;
> + size_t num_vregs_common;
> + const struct pwrseq_qca6390_vreg *vregs_wlan;
> + size_t num_vregs_wlan;
> + unsigned int pwup_delay_msec;
> +};
> +
> +struct pwrseq_qca6390_ctx {
> + struct pwrseq_device *pwrseq;
> + struct device_node *of_node;
> + const struct pwrseq_qca6390_pdata *pdata;
> + struct regulator_bulk_data *regs_common;
> + struct regulator_bulk_data *regs_wlan;
> + struct gpio_desc *bt_gpio;
> + struct gpio_desc *wlan_gpio;
> + unsigned long last_gpio_enable;
> +};
> +
> +static const struct pwrseq_qca6390_vreg pwrseq_qca6390_vregs_common[] = {
> + {
> + .name = "vddio",
> + .load_uA = 20000,
> + },
> + {
> + .name = "vddaon",
> + .load_uA = 100000,
> + },
> + {
> + .name = "vddpmu",
> + .load_uA = 1250000,
> + },
> + {
> + .name = "vddrfa0p95",
> + .load_uA = 200000,
> + },
> + {
> + .name = "vddrfa1p3",
> + .load_uA = 400000,
> + },
> + {
> + .name = "vddrfa1p9",
> + .load_uA = 400000,
> + },
> +};
> +
> +static const struct pwrseq_qca6390_vreg pwrseq_qca6390_vregs_wlan[] = {
> + {
> + .name = "vddpcie1p3",
> + .load_uA = 35000,
> + },
> + {
> + .name = "vddpcie1p9",
> + .load_uA = 15000,
> + },
> +};

I thought that we had discussed this already. According to the docs,
all PMU supplies should be powered on when the chip is being switched
on, no matter whether it is for the WiFi or for the BT.

> +
> +static void pwrseq_qca6390_ensure_gpio_delay(struct pwrseq_qca6390_ctx *ctx)
> +{
> + unsigned long diff_jiffies = jiffies - ctx->last_gpio_enable;
> + unsigned int diff_msecs = jiffies_to_msecs(diff_jiffies);
> +
> + if (diff_msecs < 100)
> + msleep(100 - diff_msecs);
> +}
> +
> +static const struct pwrseq_qca6390_pdata pwrseq_qca6390_of_data = {
> + .vregs_common = pwrseq_qca6390_vregs_common,
> + .num_vregs_common = ARRAY_SIZE(pwrseq_qca6390_vregs_common),
> + .vregs_wlan = pwrseq_qca6390_vregs_wlan,
> + .num_vregs_wlan = ARRAY_SIZE(pwrseq_qca6390_vregs_wlan),
> + .pwup_delay_msec = 16,
> +};
> +
> +static int pwrseq_qca6390_vregs_enable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + return regulator_bulk_enable(ctx->pdata->num_vregs_common,
> + ctx->regs_common);
> +}
> +
> +static int pwrseq_qca6390_vregs_disable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + return regulator_bulk_disable(ctx->pdata->num_vregs_common,
> + ctx->regs_common);
> +}
> +
> +static const struct pwrseq_unit_data pwrseq_qca6390_vregs_unit_data = {
> + .name = "regulators-enable",
> + .enable = pwrseq_qca6390_vregs_enable,
> + .disable = pwrseq_qca6390_vregs_disable,
> +};
> +
> +static const struct pwrseq_unit_data *pwrseq_qca6390_unit_deps[] = {
> + &pwrseq_qca6390_vregs_unit_data,
> + NULL
> +};
> +
> +static int pwrseq_qca6390_bt_enable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + pwrseq_qca6390_ensure_gpio_delay(ctx);
> + gpiod_set_value_cansleep(ctx->bt_gpio, 1);
> + ctx->last_gpio_enable = jiffies;
> +
> + return 0;
> +}
> +
> +static int pwrseq_qca6390_bt_disable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + gpiod_set_value_cansleep(ctx->bt_gpio, 0);
> +
> + return 0;
> +}
> +
> +static const struct pwrseq_unit_data pwrseq_qca6390_bt_unit_data = {
> + .name = "bluetooth-enable",
> + .deps = pwrseq_qca6390_unit_deps,

Can we call corresponding regulator_bulk functions from bt and wlan
enable/disable? This will save us from building the tree-like
structures (and possible loops inside that tree).

> + .enable = pwrseq_qca6390_bt_enable,
> + .disable = pwrseq_qca6390_bt_disable,
> +};
> +
> +static int pwrseq_qca6390_wlan_enable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> + int ret;
> +
> + ret = regulator_bulk_enable(ctx->pdata->num_vregs_wlan, ctx->regs_wlan);
> + if (ret)
> + return ret;
> +
> + pwrseq_qca6390_ensure_gpio_delay(ctx);
> + gpiod_set_value_cansleep(ctx->wlan_gpio, 1);
> + ctx->last_gpio_enable = jiffies;
> +
> + return 0;
> +}
> +
> +static int pwrseq_qca6390_wlan_disable(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + gpiod_set_value_cansleep(ctx->wlan_gpio, 0);
> +
> + return regulator_bulk_disable(ctx->pdata->num_vregs_wlan,
> + ctx->regs_wlan);
> +}
> +
> +static const struct pwrseq_unit_data pwrseq_qca6390_wlan_unit_data = {
> + .name = "wlan-enable",
> + .deps = pwrseq_qca6390_unit_deps,
> + .enable = pwrseq_qca6390_wlan_enable,
> + .disable = pwrseq_qca6390_wlan_disable,
> +};
> +
> +static int pwrseq_qca6390_pwup_delay(struct pwrseq_device *pwrseq)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> +
> + if (ctx->pdata->pwup_delay_msec)
> + msleep(ctx->pdata->pwup_delay_msec);
> +
> + return 0;
> +}
> +
> +static const struct pwrseq_target_data pwrseq_qca6390_bt_target_data = {
> + .name = "bluetooth",
> + .unit = &pwrseq_qca6390_bt_unit_data,
> + .post_enable = pwrseq_qca6390_pwup_delay,
> +};
> +
> +static const struct pwrseq_target_data pwrseq_qca6390_wlan_target_data = {
> + .name = "wlan",
> + .unit = &pwrseq_qca6390_wlan_unit_data,
> + .post_enable = pwrseq_qca6390_pwup_delay,
> +};
> +
> +static const struct pwrseq_target_data *pwrseq_qca6390_targets[] = {
> + &pwrseq_qca6390_bt_target_data,
> + &pwrseq_qca6390_wlan_target_data,
> + NULL
> +};
> +
> +static int pwrseq_qca6390_match(struct pwrseq_device *pwrseq,
> + struct device *dev)
> +{
> + struct pwrseq_qca6390_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
> + struct device_node *dev_node = dev->of_node;
> +
> + /*
> + * The PMU supplies power to the Bluetooth and WLAN modules. both
> + * consume the PMU AON output so check the presence of the
> + * 'vddaon-supply' property and whether it leads us to the right
> + * device.
> + */
> + if (!of_property_present(dev_node, "vddaon-supply"))
> + return 0;
> +
> + struct device_node *reg_node __free(device_node) =
> + of_parse_phandle(dev_node, "vddaon-supply", 0);
> + if (!reg_node)
> + return 0;
> +
> + /*
> + * `reg_node` is the PMU AON regulator, its parent is the `regulators`
> + * node and finally its grandparent is the PMU device node that we're
> + * looking for.
> + */
> + if (!reg_node->parent || !reg_node->parent->parent ||
> + reg_node->parent->parent != ctx->of_node)
> + return 0;
> +
> + return 1;
> +}
> +
> +static struct regulator_bulk_data *
> +pwrseq_qca6390_get_regs(struct device *dev, size_t num_regs,
> + const struct pwrseq_qca6390_vreg *pdata)
> +{
> + struct regulator_bulk_data *regs;
> + int ret, i;
> +
> + regs = devm_kcalloc(dev, num_regs, sizeof(*regs), GFP_KERNEL);
> + if (!regs)
> + return ERR_PTR(-ENOMEM);
> +
> + for (i = 0; i < num_regs; i++)
> + regs[i].supply = pdata[i].name;
> +
> + ret = devm_regulator_bulk_get(dev, num_regs, regs);
> + if (ret < 0)
> + return ERR_PTR(ret);
> +
> + for (i = 0; i < num_regs; i++) {
> + if (!pdata[i].load_uA)
> + continue;
> +
> + ret = regulator_set_load(regs[i].consumer, pdata[i].load_uA);
> + if (ret)
> + return ERR_PTR(ret);
> + }
> +
> + return regs;
> +}
> +
> +static int pwrseq_qca6390_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct pwrseq_qca6390_ctx *ctx;
> + struct pwrseq_config config;
> +
> + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> + if (!ctx)
> + return -ENOMEM;
> +
> + ctx->of_node = dev->of_node;
> +
> + ctx->pdata = of_device_get_match_data(dev);
> + if (!ctx->pdata)
> + return dev_err_probe(dev, -ENODEV,
> + "Failed to obtain platform data\n");
> +
> + ctx->regs_common = pwrseq_qca6390_get_regs(dev,
> + ctx->pdata->num_vregs_common,
> + ctx->pdata->vregs_common);
> + if (IS_ERR(ctx->regs_common))
> + return dev_err_probe(dev, PTR_ERR(ctx->regs_common),
> + "Failed to get all regulators\n");
> +
> + ctx->regs_wlan = pwrseq_qca6390_get_regs(dev,
> + ctx->pdata->num_vregs_wlan,
> + ctx->pdata->vregs_wlan);
> + if (IS_ERR(ctx->regs_wlan))
> + return dev_err_probe(dev, PTR_ERR(ctx->regs_wlan),
> + "Failed to get all regulators\n");
> +
> + ctx->bt_gpio = devm_gpiod_get_optional(dev, "bt-enable", GPIOD_OUT_LOW);
> + if (IS_ERR(ctx->bt_gpio))
> + return dev_err_probe(dev, PTR_ERR(ctx->bt_gpio),
> + "Failed to get the Bluetooth enable GPIO\n");
> +
> + ctx->wlan_gpio = devm_gpiod_get_optional(dev, "wlan-enable",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(ctx->wlan_gpio))
> + return dev_err_probe(dev, PTR_ERR(ctx->wlan_gpio),
> + "Failed to get the WLAN enable GPIO\n");
> +
> + memset(&config, 0, sizeof(config));
> +
> + config.parent = dev;
> + config.owner = THIS_MODULE;
> + config.drvdata = ctx;
> + config.match = pwrseq_qca6390_match;
> + config.targets = pwrseq_qca6390_targets;
> +
> + ctx->pwrseq = devm_pwrseq_device_register(dev, &config);
> + if (IS_ERR(ctx->pwrseq))
> + return dev_err_probe(dev, PTR_ERR(ctx->pwrseq),
> + "Failed to register the power sequencer\n");
> +
> + return 0;
> +}
> +
> +static const struct of_device_id pwrseq_qca6390_of_match[] = {
> + {
> + .compatible = "qcom,qca6390-pmu",
> + .data = &pwrseq_qca6390_of_data,
> + },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, pwrseq_qca6390_of_match);
> +
> +static struct platform_driver pwrseq_qca6390_driver = {
> + .driver = {
> + .name = "pwrseq-qca6390",
> + .of_match_table = pwrseq_qca6390_of_match,
> + },
> + .probe = pwrseq_qca6390_probe,
> +};
> +module_platform_driver(pwrseq_qca6390_driver);
> +
> +MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
> +MODULE_DESCRIPTION("QCA6390 PMU power sequencing driver");
> +MODULE_LICENSE("GPL");
> --
> 2.40.1
>


--
With best wishes
Dmitry