1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/pci/pwrctrl/generic.c b/drivers/pci/pwrctrl/generic.c
new file mode 100644
index 000000000000..1ae19450a455
--- /dev/null
+++ b/drivers/pci/pwrctrl/generic.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of_graph.h>
+#include <linux/pci-pwrctrl.h>
+#include <linux/platform_device.h>
+#include <linux/pwrseq/consumer.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+struct slot_pwrctrl {
+	struct pci_pwrctrl pwrctrl;
+	struct regulator_bulk_data *supplies;
+	int num_supplies;
+	struct clk *clk;
+	struct pwrseq_desc *pwrseq;
+};
+
+static int slot_pwrctrl_power_on(struct pci_pwrctrl *pwrctrl)
+{
+	struct slot_pwrctrl *slot = container_of(pwrctrl,
+						struct slot_pwrctrl, pwrctrl);
+	int ret;
+
+	if (slot->pwrseq) {
+		pwrseq_power_on(slot->pwrseq);
+		return 0;
+	}
+
+	ret = regulator_bulk_enable(slot->num_supplies, slot->supplies);
+	if (ret < 0) {
+		dev_err(slot->pwrctrl.dev, "Failed to enable slot regulators\n");
+		return ret;
+	}
+
+	return clk_prepare_enable(slot->clk);
+}
+
+static int slot_pwrctrl_power_off(struct pci_pwrctrl *pwrctrl)
+{
+	struct slot_pwrctrl *slot = container_of(pwrctrl,
+						struct slot_pwrctrl, pwrctrl);
+
+	if (slot->pwrseq) {
+		pwrseq_power_off(slot->pwrseq);
+		return 0;
+	}
+
+	regulator_bulk_disable(slot->num_supplies, slot->supplies);
+	clk_disable_unprepare(slot->clk);
+
+	return 0;
+}
+
+static void devm_slot_pwrctrl_release(void *data)
+{
+	struct slot_pwrctrl *slot = data;
+
+	regulator_bulk_free(slot->num_supplies, slot->supplies);
+}
+
+static int slot_pwrctrl_probe(struct platform_device *pdev)
+{
+	struct slot_pwrctrl *slot;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	slot = devm_kzalloc(dev, sizeof(*slot), GFP_KERNEL);
+	if (!slot)
+		return -ENOMEM;
+
+	if (of_graph_is_present(dev_of_node(dev))) {
+		slot->pwrseq = devm_pwrseq_get(dev, "pcie");
+		if (IS_ERR(slot->pwrseq))
+			return dev_err_probe(dev, PTR_ERR(slot->pwrseq),
+				     "Failed to get the power sequencer\n");
+
+		goto skip_resources;
+	}
+
+	ret = of_regulator_bulk_get_all(dev, dev_of_node(dev),
+					&slot->supplies);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Failed to get slot regulators\n");
+
+	slot->num_supplies = ret;
+
+	slot->clk = devm_clk_get_optional(dev, NULL);
+	if (IS_ERR(slot->clk))
+		return dev_err_probe(dev, PTR_ERR(slot->clk),
+				     "Failed to enable slot clock\n");
+
+skip_resources:
+	slot->pwrctrl.power_on = slot_pwrctrl_power_on;
+	slot->pwrctrl.power_off = slot_pwrctrl_power_off;
+
+	ret = devm_add_action_or_reset(dev, devm_slot_pwrctrl_release, slot);
+	if (ret)
+		return ret;
+
+	pci_pwrctrl_init(&slot->pwrctrl, dev);
+
+	ret = devm_pci_pwrctrl_device_set_ready(dev, &slot->pwrctrl);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to register pwrctrl driver\n");
+
+	return 0;
+}
+
+static const struct of_device_id slot_pwrctrl_of_match[] = {
+	{
+		.compatible = "pciclass,0604",
+	},
+	/* Renesas UPD720201/UPD720202 USB 3.0 xHCI Host Controller */
+	{
+		.compatible = "pci1912,0014",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, slot_pwrctrl_of_match);
+
+static struct platform_driver slot_pwrctrl_driver = {
+	.driver = {
+		.name = "pci-pwrctrl-slot",
+		.of_match_table = slot_pwrctrl_of_match,
+	},
+	.probe = slot_pwrctrl_probe,
+};
+module_platform_driver(slot_pwrctrl_driver);
+
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
+MODULE_DESCRIPTION("Generic PCI Power Control driver for PCI Slots");
+MODULE_LICENSE("GPL");