diff options
Diffstat (limited to 'drivers/pci/pwrctrl')
| -rw-r--r-- | drivers/pci/pwrctrl/Kconfig | 33 | ||||
| -rw-r--r-- | drivers/pci/pwrctrl/Makefile | 9 | ||||
| -rw-r--r-- | drivers/pci/pwrctrl/core.c | 150 | ||||
| -rw-r--r-- | drivers/pci/pwrctrl/pci-pwrctrl-pwrseq.c | 139 | ||||
| -rw-r--r-- | drivers/pci/pwrctrl/slot.c | 93 |
5 files changed, 424 insertions, 0 deletions
diff --git a/drivers/pci/pwrctrl/Kconfig b/drivers/pci/pwrctrl/Kconfig new file mode 100644 index 000000000000..6956c1854811 --- /dev/null +++ b/drivers/pci/pwrctrl/Kconfig @@ -0,0 +1,33 @@ +# SPDX-License-Identifier: GPL-2.0-only + +config HAVE_PWRCTRL + bool + +config PCI_PWRCTRL + tristate + +config PCI_PWRCTRL_PWRSEQ + tristate + select POWER_SEQUENCING + select PCI_PWRCTRL + +config PCI_PWRCTRL_SLOT + tristate "PCI Power Control driver for PCI slots" + select PCI_PWRCTRL + help + Say Y here to enable the PCI Power Control driver to control the power + state of PCI slots. + + This is a generic driver that controls the power state of different + PCI slots. The voltage regulators powering the rails of the PCI slots + are expected to be defined in the devicetree node of the PCI bridge. + +# deprecated +config HAVE_PWRCTL + bool + select HAVE_PWRCTRL + +# deprecated +config PCI_PWRCTL_PWRSEQ + tristate + select PCI_PWRCTRL_PWRSEQ diff --git a/drivers/pci/pwrctrl/Makefile b/drivers/pci/pwrctrl/Makefile new file mode 100644 index 000000000000..a4e5808d7850 --- /dev/null +++ b/drivers/pci/pwrctrl/Makefile @@ -0,0 +1,9 @@ +# SPDX-License-Identifier: GPL-2.0-only + +obj-$(CONFIG_PCI_PWRCTRL) += pci-pwrctrl-core.o +pci-pwrctrl-core-y := core.o + +obj-$(CONFIG_PCI_PWRCTRL_PWRSEQ) += pci-pwrctrl-pwrseq.o + +obj-$(CONFIG_PCI_PWRCTRL_SLOT) += pci-pwrctrl-slot.o +pci-pwrctrl-slot-y := slot.o diff --git a/drivers/pci/pwrctrl/core.c b/drivers/pci/pwrctrl/core.c new file mode 100644 index 000000000000..6bdbfed584d6 --- /dev/null +++ b/drivers/pci/pwrctrl/core.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Linaro Ltd. + */ + +#include <linux/device.h> +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/pci-pwrctrl.h> +#include <linux/property.h> +#include <linux/slab.h> + +static int pci_pwrctrl_notify(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct pci_pwrctrl *pwrctrl = container_of(nb, struct pci_pwrctrl, nb); + struct device *dev = data; + + if (dev_fwnode(dev) != dev_fwnode(pwrctrl->dev)) + return NOTIFY_DONE; + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + /* + * We will have two struct device objects bound to two different + * drivers on different buses but consuming the same DT node. We + * must not bind the pins twice in this case but only once for + * the first device to be added. + * + * If we got here then the PCI device is the second after the + * power control platform device. Mark its OF node as reused. + */ + dev->of_node_reused = true; + break; + } + + return NOTIFY_DONE; +} + +static void rescan_work_func(struct work_struct *work) +{ + struct pci_pwrctrl *pwrctrl = container_of(work, + struct pci_pwrctrl, work); + + pci_lock_rescan_remove(); + pci_rescan_bus(to_pci_host_bridge(pwrctrl->dev->parent)->bus); + pci_unlock_rescan_remove(); +} + +/** + * pci_pwrctrl_init() - Initialize the PCI power control context struct + * + * @pwrctrl: PCI power control data + * @dev: Parent device + */ +void pci_pwrctrl_init(struct pci_pwrctrl *pwrctrl, struct device *dev) +{ + pwrctrl->dev = dev; + INIT_WORK(&pwrctrl->work, rescan_work_func); +} +EXPORT_SYMBOL_GPL(pci_pwrctrl_init); + +/** + * pci_pwrctrl_device_set_ready() - Notify the pwrctrl subsystem that the PCI + * device is powered-up and ready to be detected. + * + * @pwrctrl: PCI power control data. + * + * Returns: + * 0 on success, negative error number on error. + * + * Note: + * This function returning 0 doesn't mean the device was detected. It means, + * that the bus rescan was successfully started. The device will get bound to + * its PCI driver asynchronously. + */ +int pci_pwrctrl_device_set_ready(struct pci_pwrctrl *pwrctrl) +{ + int ret; + + if (!pwrctrl->dev) + return -ENODEV; + + pwrctrl->nb.notifier_call = pci_pwrctrl_notify; + ret = bus_register_notifier(&pci_bus_type, &pwrctrl->nb); + if (ret) + return ret; + + schedule_work(&pwrctrl->work); + + return 0; +} +EXPORT_SYMBOL_GPL(pci_pwrctrl_device_set_ready); + +/** + * pci_pwrctrl_device_unset_ready() - Notify the pwrctrl subsystem that the PCI + * device is about to be powered-down. + * + * @pwrctrl: PCI power control data. + */ +void pci_pwrctrl_device_unset_ready(struct pci_pwrctrl *pwrctrl) +{ + cancel_work_sync(&pwrctrl->work); + + /* + * We don't have to delete the link here. Typically, this function + * is only called when the power control device is being detached. If + * it is being detached then the child PCI device must have already + * been unbound too or the device core wouldn't let us unbind. + */ + bus_unregister_notifier(&pci_bus_type, &pwrctrl->nb); +} +EXPORT_SYMBOL_GPL(pci_pwrctrl_device_unset_ready); + +static void devm_pci_pwrctrl_device_unset_ready(void *data) +{ + struct pci_pwrctrl *pwrctrl = data; + + pci_pwrctrl_device_unset_ready(pwrctrl); +} + +/** + * devm_pci_pwrctrl_device_set_ready - Managed variant of + * pci_pwrctrl_device_set_ready(). + * + * @dev: Device managing this pwrctrl provider. + * @pwrctrl: PCI power control data. + * + * Returns: + * 0 on success, negative error number on error. + */ +int devm_pci_pwrctrl_device_set_ready(struct device *dev, + struct pci_pwrctrl *pwrctrl) +{ + int ret; + + ret = pci_pwrctrl_device_set_ready(pwrctrl); + if (ret) + return ret; + + return devm_add_action_or_reset(dev, + devm_pci_pwrctrl_device_unset_ready, + pwrctrl); +} +EXPORT_SYMBOL_GPL(devm_pci_pwrctrl_device_set_ready); + +MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>"); +MODULE_DESCRIPTION("PCI Device Power Control core driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/pci/pwrctrl/pci-pwrctrl-pwrseq.c b/drivers/pci/pwrctrl/pci-pwrctrl-pwrseq.c new file mode 100644 index 000000000000..4e664e7b8dd2 --- /dev/null +++ b/drivers/pci/pwrctrl/pci-pwrctrl-pwrseq.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Linaro Ltd. + */ + +#include <linux/device.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/pci-pwrctrl.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/pwrseq/consumer.h> +#include <linux/slab.h> +#include <linux/types.h> + +struct pci_pwrctrl_pwrseq_data { + struct pci_pwrctrl ctx; + struct pwrseq_desc *pwrseq; +}; + +struct pci_pwrctrl_pwrseq_pdata { + const char *target; + /* + * Called before doing anything else to perform device-specific + * verification between requesting the power sequencing handle. + */ + int (*validate_device)(struct device *dev); +}; + +static int pci_pwrctrl_pwrseq_qcm_wcn_validate_device(struct device *dev) +{ + /* + * Old device trees for some platforms already define wifi nodes for + * the WCN family of chips since before power sequencing was added + * upstream. + * + * These nodes don't consume the regulator outputs from the PMU, and + * if we allow this driver to bind to one of such "incomplete" nodes, + * we'll see a kernel log error about the indefinite probe deferral. + * + * Check the existence of the regulator supply that exists on all + * WCN models before moving forward. + */ + if (!device_property_present(dev, "vddaon-supply")) + return -ENODEV; + + return 0; +} + +static const struct pci_pwrctrl_pwrseq_pdata pci_pwrctrl_pwrseq_qcom_wcn_pdata = { + .target = "wlan", + .validate_device = pci_pwrctrl_pwrseq_qcm_wcn_validate_device, +}; + +static void devm_pci_pwrctrl_pwrseq_power_off(void *data) +{ + struct pwrseq_desc *pwrseq = data; + + pwrseq_power_off(pwrseq); +} + +static int pci_pwrctrl_pwrseq_probe(struct platform_device *pdev) +{ + const struct pci_pwrctrl_pwrseq_pdata *pdata; + struct pci_pwrctrl_pwrseq_data *data; + struct device *dev = &pdev->dev; + int ret; + + pdata = device_get_match_data(dev); + if (!pdata || !pdata->target) + return -EINVAL; + + if (pdata->validate_device) { + ret = pdata->validate_device(dev); + if (ret) + return ret; + } + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->pwrseq = devm_pwrseq_get(dev, pdata->target); + if (IS_ERR(data->pwrseq)) + return dev_err_probe(dev, PTR_ERR(data->pwrseq), + "Failed to get the power sequencer\n"); + + ret = pwrseq_power_on(data->pwrseq); + if (ret) + return dev_err_probe(dev, ret, + "Failed to power-on the device\n"); + + ret = devm_add_action_or_reset(dev, devm_pci_pwrctrl_pwrseq_power_off, + data->pwrseq); + if (ret) + return ret; + + pci_pwrctrl_init(&data->ctx, dev); + + ret = devm_pci_pwrctrl_device_set_ready(dev, &data->ctx); + if (ret) + return dev_err_probe(dev, ret, + "Failed to register the pwrctrl wrapper\n"); + + return 0; +} + +static const struct of_device_id pci_pwrctrl_pwrseq_of_match[] = { + { + /* ATH11K in QCA6390 package. */ + .compatible = "pci17cb,1101", + .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, + }, + { + /* ATH11K in WCN6855 package. */ + .compatible = "pci17cb,1103", + .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, + }, + { + /* ATH12K in WCN7850 package. */ + .compatible = "pci17cb,1107", + .data = &pci_pwrctrl_pwrseq_qcom_wcn_pdata, + }, + { } +}; +MODULE_DEVICE_TABLE(of, pci_pwrctrl_pwrseq_of_match); + +static struct platform_driver pci_pwrctrl_pwrseq_driver = { + .driver = { + .name = "pci-pwrctrl-pwrseq", + .of_match_table = pci_pwrctrl_pwrseq_of_match, + }, + .probe = pci_pwrctrl_pwrseq_probe, +}; +module_platform_driver(pci_pwrctrl_pwrseq_driver); + +MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>"); +MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices"); +MODULE_LICENSE("GPL"); diff --git a/drivers/pci/pwrctrl/slot.c b/drivers/pci/pwrctrl/slot.c new file mode 100644 index 000000000000..18becc144913 --- /dev/null +++ b/drivers/pci/pwrctrl/slot.c @@ -0,0 +1,93 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Linaro Ltd. + * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> + */ + +#include <linux/device.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/pci-pwrctrl.h> +#include <linux/platform_device.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> + +struct pci_pwrctrl_slot_data { + struct pci_pwrctrl ctx; + struct regulator_bulk_data *supplies; + int num_supplies; +}; + +static void devm_pci_pwrctrl_slot_power_off(void *data) +{ + struct pci_pwrctrl_slot_data *slot = data; + + regulator_bulk_disable(slot->num_supplies, slot->supplies); + regulator_bulk_free(slot->num_supplies, slot->supplies); +} + +static int pci_pwrctrl_slot_probe(struct platform_device *pdev) +{ + struct pci_pwrctrl_slot_data *slot; + struct device *dev = &pdev->dev; + int ret; + + slot = devm_kzalloc(dev, sizeof(*slot), GFP_KERNEL); + if (!slot) + return -ENOMEM; + + ret = of_regulator_bulk_get_all(dev, dev_of_node(dev), + &slot->supplies); + if (ret < 0) { + dev_err_probe(dev, ret, "Failed to get slot regulators\n"); + return ret; + } + + slot->num_supplies = ret; + ret = regulator_bulk_enable(slot->num_supplies, slot->supplies); + if (ret < 0) { + dev_err_probe(dev, ret, "Failed to enable slot regulators\n"); + goto err_regulator_free; + } + + ret = devm_add_action_or_reset(dev, devm_pci_pwrctrl_slot_power_off, + slot); + if (ret) + goto err_regulator_disable; + + pci_pwrctrl_init(&slot->ctx, dev); + + ret = devm_pci_pwrctrl_device_set_ready(dev, &slot->ctx); + if (ret) + return dev_err_probe(dev, ret, "Failed to register pwrctrl driver\n"); + + return 0; + +err_regulator_disable: + regulator_bulk_disable(slot->num_supplies, slot->supplies); +err_regulator_free: + regulator_bulk_free(slot->num_supplies, slot->supplies); + + return ret; +} + +static const struct of_device_id pci_pwrctrl_slot_of_match[] = { + { + .compatible = "pciclass,0604", + }, + { } +}; +MODULE_DEVICE_TABLE(of, pci_pwrctrl_slot_of_match); + +static struct platform_driver pci_pwrctrl_slot_driver = { + .driver = { + .name = "pci-pwrctrl-slot", + .of_match_table = pci_pwrctrl_slot_of_match, + }, + .probe = pci_pwrctrl_slot_probe, +}; +module_platform_driver(pci_pwrctrl_slot_driver); + +MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>"); +MODULE_DESCRIPTION("Generic PCI Power Control driver for PCI Slots"); +MODULE_LICENSE("GPL"); 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