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-rw-r--r--drivers/pci/pwrctrl/Kconfig12
-rw-r--r--drivers/pci/pwrctrl/Makefile6
-rw-r--r--drivers/pci/pwrctrl/core.c148
-rw-r--r--drivers/pci/pwrctrl/pci-pwrctrl-pwrseq.c139
4 files changed, 305 insertions, 0 deletions
diff --git a/drivers/pci/pwrctrl/Kconfig b/drivers/pci/pwrctrl/Kconfig
new file mode 100644
index 000000000000..54589bb2403b
--- /dev/null
+++ b/drivers/pci/pwrctrl/Kconfig
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config HAVE_PWRCTL
+ bool
+
+config PCI_PWRCTL
+ tristate
+
+config PCI_PWRCTL_PWRSEQ
+ tristate
+ select POWER_SEQUENCING
+ select PCI_PWRCTL
diff --git a/drivers/pci/pwrctrl/Makefile b/drivers/pci/pwrctrl/Makefile
new file mode 100644
index 000000000000..75c7ce531c7e
--- /dev/null
+++ b/drivers/pci/pwrctrl/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_PCI_PWRCTL) += pci-pwrctrl-core.o
+pci-pwrctrl-core-y := core.o
+
+obj-$(CONFIG_PCI_PWRCTL_PWRSEQ) += pci-pwrctrl-pwrseq.o
diff --git a/drivers/pci/pwrctrl/core.c b/drivers/pci/pwrctrl/core.c
new file mode 100644
index 000000000000..2fb174db91e5
--- /dev/null
+++ b/drivers/pci/pwrctrl/core.c
@@ -0,0 +1,148 @@
+// 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_dev(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)
+{
+ /*
+ * 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");
generated by cgit (git 2.34.1) at 2025-07-30 11:59:43 +0000