2024-06-05 13:41:47

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v9 0/2] pwrseq: introduce the subsystem and first driver

From: Bartosz Golaszewski <[email protected]>

Hi!

These are the power sequencing patches sent separately after some
improvements suggested by Bjorn Helgaas. I intend to pick them up into a
new branch and maintain the subsystem from now on. I then plan to
provide an immutable tag to the Bluetooth and PCI subsystems so that the
rest of the C changes can be applied. This new branch will then be
directly sent to Linus Torvalds for the next merge window.

Changelog:

Since v8:
- split the pwrseq patches out into their own series
- rename incref/decref functions to get/put for consistency
- fix typos
- make it very explicit in docs that arrays of targets and units must be
NULL-terminated
- Link to v8: https://lore.kernel.org/r/[email protected]

Since v7:
- added DTS changes for sm8650-hdk
- added circular dependency detection for pwrseq units
- fixed a KASAN reported use-after-free error in remove path
- improve Kconfig descriptions
- fix typos in bindings and Kconfig
- fixed issues reported by smatch
- fix the unbind path in PCI pwrctl
- lots of minor improvements to the pwrseq core

Since v6:
- kernel doc fixes
- drop myself from the DT bindings maintainers list for ath12k
- wait until the PCI bridge device is fully added before creating the
PCI pwrctl platform devices for its sub-nodes, otherwise we may see
sysfs and procfs attribute failures (due to duplication, we're
basically trying to probe the same device twice at the same time)
- I kept the regulators for QCA6390's ath11k as required as they only
apply to this specific Qualcomm package

Since v5:
- unify the approach to modelling the WCN WLAN/BT chips by always exposing
the PMU node on the device tree and making the WLAN and BT nodes become
consumers of its power outputs; this includes a major rework of the DT
sources, bindings and driver code; there's no more a separate PCI
pwrctl driver for WCN7850, instead its power-up sequence was moved
into the pwrseq driver common for all WCN chips
- don't set load_uA from new regulator consumers
- fix reported kerneldoc issues
- drop voltage ranges for PMU outputs from DT
- many minor tweaks and reworks

v1: Original RFC:

https://lore.kernel.org/lkml/[email protected]/T/

v2: First real patch series (should have been PATCH v2) adding what I
referred to back then as PCI power sequencing:

https://lore.kernel.org/linux-arm-kernel/2024021413-grumbling-unlivable-c145@gregkh/T/

v3: RFC for the DT representation of the PMU supplying the WLAN and BT
modules inside the QCA6391 package (was largely separate from the
series but probably should have been called PATCH or RFC v3):

https://lore.kernel.org/all/CAMRc=Mc+GNoi57eTQg71DXkQKjdaoAmCpB=h2ndEpGnmdhVV-Q@mail.gmail.com/T/

v4: Second attempt at the full series with changed scope (introduction of
the pwrseq subsystem, should have been RFC v4)

https://lore.kernel.org/lkml/[email protected]/T/

v5: Two different ways of handling QCA6390 and WCN7850:

https://lore.kernel.org/lkml/[email protected]/

Bartosz Golaszewski (2):
power: sequencing: implement the pwrseq core
power: pwrseq: add a driver for the PMU module on the QCom WCN
chipsets

MAINTAINERS | 8 +
drivers/power/Kconfig | 1 +
drivers/power/Makefile | 1 +
drivers/power/sequencing/Kconfig | 29 +
drivers/power/sequencing/Makefile | 6 +
drivers/power/sequencing/core.c | 1105 ++++++++++++++++++++
drivers/power/sequencing/pwrseq-qcom-wcn.c | 336 ++++++
include/linux/pwrseq/consumer.h | 56 +
include/linux/pwrseq/provider.h | 75 ++
9 files changed, 1617 insertions(+)
create mode 100644 drivers/power/sequencing/Kconfig
create mode 100644 drivers/power/sequencing/Makefile
create mode 100644 drivers/power/sequencing/core.c
create mode 100644 drivers/power/sequencing/pwrseq-qcom-wcn.c
create mode 100644 include/linux/pwrseq/consumer.h
create mode 100644 include/linux/pwrseq/provider.h

--
2.40.1



2024-06-05 15:09:29

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v9 2/2] power: pwrseq: add a driver for the PMU module on the QCom WCN chipsets

From: Bartosz Golaszewski <[email protected]>

This adds the power sequencing driver for the PMU modules present on the
Qualcomm WCN Bluetooth and Wifi chipsets. It uses the pwrseq subsystem
and knows how to match the sequencer to the consumer device by verifying
the relevant properties and DT layout. Using this driver will allow the
BT and WLAN drivers to respect the required delays between enabling the
two modules.

Tested-by: Amit Pundir <[email protected]>
Tested-by: Neil Armstrong <[email protected]> # on SM8550-QRD, SM8650-QRD & SM8650-HDK
Tested-by: Caleb Connolly <[email protected]> # OnePlus 8T
Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/power/sequencing/Kconfig | 17 ++
drivers/power/sequencing/Makefile | 2 +
drivers/power/sequencing/pwrseq-qcom-wcn.c | 336 +++++++++++++++++++++
3 files changed, 355 insertions(+)
create mode 100644 drivers/power/sequencing/pwrseq-qcom-wcn.c

diff --git a/drivers/power/sequencing/Kconfig b/drivers/power/sequencing/Kconfig
index ba5732b1dbf8..c9f1cdb66524 100644
--- a/drivers/power/sequencing/Kconfig
+++ b/drivers/power/sequencing/Kconfig
@@ -10,3 +10,20 @@ menuconfig POWER_SEQUENCING
during power-up.

If unsure, say no.
+
+if POWER_SEQUENCING
+
+config POWER_SEQUENCING_QCOM_WCN
+ tristate "Qualcomm WCN family PMU driver"
+ default m if ARCH_QCOM
+ help
+ Say Y here to enable the power sequencing driver for Qualcomm
+ WCN Bluetooth/WLAN chipsets.
+
+ Typically, a package from the Qualcomm WCN family 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 or else we'd risk not
+ respecting the required delays between enabling Bluetooth and WLAN.
+
+endif
diff --git a/drivers/power/sequencing/Makefile b/drivers/power/sequencing/Makefile
index dcdf8c0c159e..2eec2df7912d 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_QCOM_WCN) += pwrseq-qcom-wcn.o
diff --git a/drivers/power/sequencing/pwrseq-qcom-wcn.c b/drivers/power/sequencing/pwrseq-qcom-wcn.c
new file mode 100644
index 000000000000..42dacfda745e
--- /dev/null
+++ b/drivers/power/sequencing/pwrseq-qcom-wcn.c
@@ -0,0 +1,336 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#include <linux/clk.h>
+#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_qcom_wcn_pdata {
+ const char *const *vregs;
+ size_t num_vregs;
+ unsigned int pwup_delay_ms;
+ unsigned int gpio_enable_delay_ms;
+};
+
+struct pwrseq_qcom_wcn_ctx {
+ struct pwrseq_device *pwrseq;
+ struct device_node *of_node;
+ const struct pwrseq_qcom_wcn_pdata *pdata;
+ struct regulator_bulk_data *regs;
+ struct gpio_desc *bt_gpio;
+ struct gpio_desc *wlan_gpio;
+ struct clk *clk;
+ unsigned long last_gpio_enable_jf;
+};
+
+static void pwrseq_qcom_wcn_ensure_gpio_delay(struct pwrseq_qcom_wcn_ctx *ctx)
+{
+ unsigned long diff_jiffies;
+ unsigned int diff_msecs;
+
+ if (!ctx->pdata->gpio_enable_delay_ms)
+ return;
+
+ diff_jiffies = jiffies - ctx->last_gpio_enable_jf;
+ diff_msecs = jiffies_to_msecs(diff_jiffies);
+
+ if (diff_msecs < ctx->pdata->gpio_enable_delay_ms)
+ msleep(ctx->pdata->gpio_enable_delay_ms - diff_msecs);
+}
+
+static int pwrseq_qcom_wcn_vregs_enable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ return regulator_bulk_enable(ctx->pdata->num_vregs, ctx->regs);
+}
+
+static int pwrseq_qcom_wcn_vregs_disable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ return regulator_bulk_disable(ctx->pdata->num_vregs, ctx->regs);
+}
+
+static const struct pwrseq_unit_data pwrseq_qcom_wcn_vregs_unit_data = {
+ .name = "regulators-enable",
+ .enable = pwrseq_qcom_wcn_vregs_enable,
+ .disable = pwrseq_qcom_wcn_vregs_disable,
+};
+
+static int pwrseq_qcom_wcn_clk_enable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ return clk_prepare_enable(ctx->clk);
+}
+
+static int pwrseq_qcom_wcn_clk_disable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ clk_disable_unprepare(ctx->clk);
+
+ return 0;
+}
+
+static const struct pwrseq_unit_data pwrseq_qcom_wcn_clk_unit_data = {
+ .name = "clock-enable",
+ .enable = pwrseq_qcom_wcn_clk_enable,
+ .disable = pwrseq_qcom_wcn_clk_disable,
+};
+
+static const struct pwrseq_unit_data *pwrseq_qcom_wcn_unit_deps[] = {
+ &pwrseq_qcom_wcn_vregs_unit_data,
+ &pwrseq_qcom_wcn_clk_unit_data,
+ NULL
+};
+
+static int pwrseq_qcom_wcn_bt_enable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ pwrseq_qcom_wcn_ensure_gpio_delay(ctx);
+ gpiod_set_value_cansleep(ctx->bt_gpio, 1);
+ ctx->last_gpio_enable_jf = jiffies;
+
+ return 0;
+}
+
+static int pwrseq_qcom_wcn_bt_disable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ gpiod_set_value_cansleep(ctx->bt_gpio, 0);
+
+ return 0;
+}
+
+static const struct pwrseq_unit_data pwrseq_qcom_wcn_bt_unit_data = {
+ .name = "bluetooth-enable",
+ .deps = pwrseq_qcom_wcn_unit_deps,
+ .enable = pwrseq_qcom_wcn_bt_enable,
+ .disable = pwrseq_qcom_wcn_bt_disable,
+};
+
+static int pwrseq_qcom_wcn_wlan_enable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ pwrseq_qcom_wcn_ensure_gpio_delay(ctx);
+ gpiod_set_value_cansleep(ctx->wlan_gpio, 1);
+ ctx->last_gpio_enable_jf = jiffies;
+
+ return 0;
+}
+
+static int pwrseq_qcom_wcn_wlan_disable(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ gpiod_set_value_cansleep(ctx->wlan_gpio, 0);
+
+ return 0;
+}
+
+static const struct pwrseq_unit_data pwrseq_qcom_wcn_wlan_unit_data = {
+ .name = "wlan-enable",
+ .deps = pwrseq_qcom_wcn_unit_deps,
+ .enable = pwrseq_qcom_wcn_wlan_enable,
+ .disable = pwrseq_qcom_wcn_wlan_disable,
+};
+
+static int pwrseq_qcom_wcn_pwup_delay(struct pwrseq_device *pwrseq)
+{
+ struct pwrseq_qcom_wcn_ctx *ctx = pwrseq_device_get_drvdata(pwrseq);
+
+ if (ctx->pdata->pwup_delay_ms)
+ msleep(ctx->pdata->pwup_delay_ms);
+
+ return 0;
+}
+
+static const struct pwrseq_target_data pwrseq_qcom_wcn_bt_target_data = {
+ .name = "bluetooth",
+ .unit = &pwrseq_qcom_wcn_bt_unit_data,
+ .post_enable = pwrseq_qcom_wcn_pwup_delay,
+};
+
+static const struct pwrseq_target_data pwrseq_qcom_wcn_wlan_target_data = {
+ .name = "wlan",
+ .unit = &pwrseq_qcom_wcn_wlan_unit_data,
+ .post_enable = pwrseq_qcom_wcn_pwup_delay,
+};
+
+static const struct pwrseq_target_data *pwrseq_qcom_wcn_targets[] = {
+ &pwrseq_qcom_wcn_bt_target_data,
+ &pwrseq_qcom_wcn_wlan_target_data,
+ NULL
+};
+
+static const char *const pwrseq_qca6390_vregs[] = {
+ "vddio",
+ "vddaon",
+ "vddpmu",
+ "vddrfa0p95",
+ "vddrfa1p3",
+ "vddrfa1p9",
+ "vddpcie1p3",
+ "vddpcie1p9",
+};
+
+static const struct pwrseq_qcom_wcn_pdata pwrseq_qca6390_of_data = {
+ .vregs = pwrseq_qca6390_vregs,
+ .num_vregs = ARRAY_SIZE(pwrseq_qca6390_vregs),
+ .pwup_delay_ms = 60,
+ .gpio_enable_delay_ms = 100,
+};
+
+static const char *const pwrseq_wcn7850_vregs[] = {
+ "vdd",
+ "vddio",
+ "vddio1p2",
+ "vddaon",
+ "vdddig",
+ "vddrfa1p2",
+ "vddrfa1p8",
+};
+
+static const struct pwrseq_qcom_wcn_pdata pwrseq_wcn7850_of_data = {
+ .vregs = pwrseq_wcn7850_vregs,
+ .num_vregs = ARRAY_SIZE(pwrseq_wcn7850_vregs),
+ .pwup_delay_ms = 50,
+};
+
+static int pwrseq_qcom_wcn_match(struct pwrseq_device *pwrseq,
+ struct device *dev)
+{
+ struct pwrseq_qcom_wcn_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 int pwrseq_qcom_wcn_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pwrseq_qcom_wcn_ctx *ctx;
+ struct pwrseq_config config;
+ int i, ret;
+
+ 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 = devm_kcalloc(dev, ctx->pdata->num_vregs,
+ sizeof(*ctx->regs), GFP_KERNEL);
+ if (!ctx->regs)
+ return -ENOMEM;
+
+ for (i = 0; i < ctx->pdata->num_vregs; i++)
+ ctx->regs[i].supply = ctx->pdata->vregs[i];
+
+ ret = devm_regulator_bulk_get(dev, ctx->pdata->num_vregs, ctx->regs);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "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");
+
+ ctx->clk = devm_clk_get_optional(dev, NULL);
+ if (IS_ERR(ctx->clk))
+ return dev_err_probe(dev, PTR_ERR(ctx->clk),
+ "Failed to get the reference clock\n");
+
+ memset(&config, 0, sizeof(config));
+
+ config.parent = dev;
+ config.owner = THIS_MODULE;
+ config.drvdata = ctx;
+ config.match = pwrseq_qcom_wcn_match;
+ config.targets = pwrseq_qcom_wcn_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_qcom_wcn_of_match[] = {
+ {
+ .compatible = "qcom,qca6390-pmu",
+ .data = &pwrseq_qca6390_of_data,
+ },
+ {
+ .compatible = "qcom,wcn7850-pmu",
+ .data = &pwrseq_wcn7850_of_data,
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, pwrseq_qcom_wcn_of_match);
+
+static struct platform_driver pwrseq_qcom_wcn_driver = {
+ .driver = {
+ .name = "pwrseq-qcom_wcn",
+ .of_match_table = pwrseq_qcom_wcn_of_match,
+ },
+ .probe = pwrseq_qcom_wcn_probe,
+};
+module_platform_driver(pwrseq_qcom_wcn_driver);
+
+MODULE_AUTHOR("Bartosz Golaszewski <[email protected]>");
+MODULE_DESCRIPTION("Qualcomm WCN PMU power sequencing driver");
+MODULE_LICENSE("GPL");
--
2.40.1