Merge "drivers: thermal: regulator-cdev: Snapshot of regulator cooling device"

drivers/thermal/qcom/Kconfig

@@ -118,3 +118,12 @@ config QTI_SDPM_CLOCK_MONITOR
 	    for different clock rate change notifications and write the clock
 	    rate into the SDPM CSR register. This driver will receive the clock
 	    list and the CSR details from devicetree.
+
+config REGULATOR_COOLING_DEVICE
+	tristate "Regulator voltage floor cooling device"
+	depends on REGULATOR && THERMAL_OF
+	help
+	  This implements a mitigation device to place a minimum voltage floor
+	  on a particular regulator. This mitigation device will be used by low
+	  temperature reliability rules to mitigate a regulator at nominal
+	  voltage.

drivers/thermal/qcom/Makefile

@@ -19,3 +19,4 @@ obj-$(CONFIG_QTI_THERMAL_LIMITS_DCVS) += msm_lmh_dcvs.o
 obj-$(CONFIG_QTI_CPU_VOLTAGE_COOLING_DEVICE) += cpu_voltage_cooling.o
 obj-$(CONFIG_QTI_POLICY_ENGINE_SENSOR) += policy_engine.o
 obj-${CONFIG_QTI_SDPM_CLOCK_MONITOR} += sdpm_clk.o
+obj-$(CONFIG_REGULATOR_COOLING_DEVICE) += regulator_cdev.o

drivers/thermal/qcom/regulator_cdev.c

@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+
+#define REG_CDEV_DRIVER "reg-cooling-device"
+
+struct reg_cooling_device {
+	struct regulator		*reg;
+	struct thermal_cooling_device	*cool_dev;
+	unsigned int			cur_state;
+	unsigned int			*lvl;
+	unsigned int			lvl_ct;
+	char				reg_name[THERMAL_NAME_LENGTH];
+	bool				reg_enable;
+};
+
+static int reg_get_max_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	struct reg_cooling_device *reg_dev = cdev->devdata;
+
+	*state = reg_dev->lvl_ct;
+	return 0;
+}
+
+static int reg_get_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	struct reg_cooling_device *reg_dev = cdev->devdata;
+
+	*state = reg_dev->cur_state;
+	return 0;
+}
+
+static int reg_set_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long state)
+{
+	struct reg_cooling_device *reg_dev = cdev->devdata;
+	int ret = 0;
+
+	if (state > reg_dev->lvl_ct)
+		return -EINVAL;
+
+	if (reg_dev->cur_state == state)
+		return ret;
+
+	ret = regulator_set_voltage(reg_dev->reg,
+			reg_dev->lvl[state], INT_MAX);
+	if (ret) {
+		dev_err(&cdev->device,
+			"switching to floor %lu err:%d\n",
+			state, ret);
+		return ret;
+	}
+	if (reg_dev->reg_enable && !state) {
+		ret = regulator_disable(reg_dev->reg);
+		if (ret) {
+			dev_err(&cdev->device,
+				"regulator disable err:%d\n", ret);
+			return ret;
+		}
+		reg_dev->reg_enable = false;
+	} else if (!reg_dev->reg_enable && state) {
+		ret = regulator_enable(reg_dev->reg);
+		if (ret) {
+			dev_err(&cdev->device,
+				"regulator enable err:%d\n", ret);
+			return ret;
+		}
+		reg_dev->reg_enable = true;
+	}
+	reg_dev->cur_state = state;
+
+	return ret;
+}
+
+static struct thermal_cooling_device_ops reg_device_ops = {
+	.get_max_state = reg_get_max_state,
+	.get_cur_state = reg_get_cur_state,
+	.set_cur_state = reg_set_cur_state,
+};
+
+static int reg_cdev_probe(struct platform_device *pdev)
+{
+	struct reg_cooling_device *reg_dev;
+	int ret = 0;
+	struct device_node *np;
+
+	np = dev_of_node(&pdev->dev);
+	if (!np) {
+		dev_err(&pdev->dev,
+			"of node not available for cooling device\n");
+		return -EINVAL;
+	}
+
+	reg_dev = devm_kzalloc(&pdev->dev, sizeof(*reg_dev), GFP_KERNEL);
+	if (!reg_dev)
+		return -ENOMEM;
+
+	reg_dev->reg = devm_regulator_get(&pdev->dev, "regulator-cdev");
+	if (IS_ERR_OR_NULL(reg_dev->reg)) {
+		ret = PTR_ERR(reg_dev->reg);
+		dev_err(&pdev->dev, "regulator register err:%d\n", ret);
+		return ret;
+	}
+	ret = of_property_count_u32_elems(np, "regulator-levels");
+	if (ret <= 0) {
+		dev_err(&pdev->dev, "Invalid levels err:%d\n", ret);
+		return ret;
+	}
+	reg_dev->lvl_ct = ret;
+	reg_dev->lvl = devm_kcalloc(&pdev->dev, reg_dev->lvl_ct,
+			sizeof(*reg_dev->lvl), GFP_KERNEL);
+	if (!reg_dev->lvl)
+		return -ENOMEM;
+	ret = of_property_read_u32_array(np, "regulator-levels",
+				reg_dev->lvl, reg_dev->lvl_ct);
+	if (ret) {
+		dev_err(&pdev->dev, "cdev level fetch err:%d\n", ret);
+		return ret;
+	}
+	/* level count is an index and it depicts the max possible index */
+	reg_dev->lvl_ct--;
+	reg_dev->cur_state = 0;
+	reg_dev->reg_enable = false;
+	strlcpy(reg_dev->reg_name, np->name, THERMAL_NAME_LENGTH);
+
+	reg_dev->cool_dev = thermal_of_cooling_device_register(
+					np, reg_dev->reg_name, reg_dev,
+					&reg_device_ops);
+	if (IS_ERR(reg_dev->cool_dev)) {
+		ret = PTR_ERR(reg_dev->cool_dev);
+		dev_err(&pdev->dev, "regulator cdev register err:%d\n",
+				ret);
+		return ret;
+	}
+
+	return ret;
+}
+
+static const struct of_device_id reg_cdev_of_match[] = {
+	{.compatible = "qcom,regulator-cooling-device", },
+	{},
+};
+
+static struct platform_driver reg_cdev_driver = {
+	.driver = {
+		.name = REG_CDEV_DRIVER,
+		.of_match_table = reg_cdev_of_match,
+	},
+	.probe = reg_cdev_probe,
+};
+builtin_platform_driver(reg_cdev_driver);
+MODULE_LICENSE("GPL v2");