Add samsung specific changes

drivers/thermal/qcom/ddr_cdev.c

@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2021-2023, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+#include <linux/module.h>
+#include <linux/thermal.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/of_device.h>
+#include <linux/interconnect.h>
+
+#define DDR_CDEV_NAME "ddr-cdev"
+
+struct ddr_cdev {
+	uint32_t cur_state;
+	uint32_t max_state;
+	struct thermal_cooling_device *cdev;
+	struct icc_path *icc_path;
+	struct device *dev;
+	uint32_t *freq_table;
+	uint32_t freq_table_size;
+};
+
+/**
+ * ddr_set_cur_state - callback function to set the ddr state.
+ * @cdev: thermal cooling device pointer.
+ * @state: set this variable to the current cooling state.
+ *
+ * Callback for the thermal cooling device to change the
+ * DDR state.
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+static int ddr_set_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long state)
+{
+	struct ddr_cdev *ddr_cdev = cdev->devdata;
+	int ret = 0;
+
+	/* Request state should be less than max_level */
+	if (state > ddr_cdev->max_state)
+		return -EINVAL;
+
+	/* Check if the old cooling action is same as new cooling action */
+	if (ddr_cdev->cur_state == state)
+		return 0;
+
+	ret = icc_set_bw(ddr_cdev->icc_path, 0, ddr_cdev->freq_table[state]);
+	if (ret < 0) {
+		dev_err(ddr_cdev->dev, "Error placing DDR freq%u. err:%d\n",
+			ddr_cdev->freq_table[state], ret);
+		return ret;
+	}
+
+	ddr_cdev->cur_state = state;
+
+	return ret;
+}
+
+/**
+ * ddr_get_cur_state - callback function to get the current cooling
+ *				state.
+ * @cdev: thermal cooling device pointer.
+ * @state: fill this variable with the current cooling state.
+ *
+ * Callback for the thermal cooling device to return the
+ * current DDR state request.
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+static int ddr_get_cur_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	struct ddr_cdev *ddr_cdev = cdev->devdata;
+	*state = ddr_cdev->cur_state;
+
+	return 0;
+}
+
+/**
+ * ddr_get_max_state - callback function to get the max cooling state.
+ * @cdev: thermal cooling device pointer.
+ * @state: fill this variable with the max cooling state.
+ *
+ * Callback for the thermal cooling device to return the DDR
+ * max cooling state.
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+static int ddr_get_max_state(struct thermal_cooling_device *cdev,
+				 unsigned long *state)
+{
+	struct ddr_cdev *ddr_cdev = cdev->devdata;
+	*state = ddr_cdev->max_state;
+
+	return 0;
+}
+
+static struct thermal_cooling_device_ops ddr_cdev_ops = {
+	.get_max_state = ddr_get_max_state,
+	.get_cur_state = ddr_get_cur_state,
+	.set_cur_state = ddr_set_cur_state,
+};
+
+static int ddr_cdev_probe(struct platform_device *pdev)
+{
+	int ret = 0, opp_ct = 0, bus_width = 1, idx = 0;
+	struct ddr_cdev *ddr_cdev = NULL;
+	struct device_node *np = pdev->dev.of_node;
+	struct device *dev = &pdev->dev;
+	uint32_t *freq_table = NULL;
+	char cdev_name[THERMAL_NAME_LENGTH] = DDR_CDEV_NAME;
+
+	ddr_cdev = devm_kzalloc(dev, sizeof(*ddr_cdev), GFP_KERNEL);
+	if (!ddr_cdev)
+		return -ENOMEM;
+	ddr_cdev->icc_path = of_icc_get(dev, NULL);
+	if (IS_ERR(ddr_cdev->icc_path)) {
+		ret = PTR_ERR(ddr_cdev->icc_path);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Unable to register icc path: %d\n",
+					ret);
+		return ret;
+	}
+
+	if (!of_find_property(np, "qcom,freq-table", &opp_ct)) {
+		dev_err(dev, "No DDR frequency entries\n");
+		ret = -ENODEV;
+		goto err_exit;
+	}
+
+	if (opp_ct <= 0) {
+		dev_err(dev, "No DDR frequency\n");
+		ret = -ENODEV;
+		goto err_exit;
+	}
+	opp_ct = opp_ct / sizeof(*freq_table);
+
+	/* Add one more entry for 0 or no DDR BW vote */
+	opp_ct++;
+
+	freq_table = devm_kcalloc(dev, opp_ct, sizeof(*freq_table), GFP_KERNEL);
+	if (!freq_table) {
+		ret = -ENOMEM;
+		goto err_exit;
+	}
+	freq_table[0] = 0;
+
+	ret = of_property_read_u32_array(np, "qcom,freq-table",
+			&freq_table[1], opp_ct - 1);
+	if (ret < 0) {
+		dev_err(dev, "DDR frequency read error:%d\n", ret);
+		goto err_exit;
+	}
+
+	ddr_cdev->freq_table = freq_table;
+	ddr_cdev->freq_table_size = opp_ct;
+	ddr_cdev->cur_state = 0;
+	ddr_cdev->max_state = opp_ct - 1;
+	ddr_cdev->dev = dev;
+
+	ret = of_property_read_u32(np, "qcom,bus-width", &bus_width);
+	if (ret < 0) {
+		dev_err(dev, "DDR bus width read error:%d\n", ret);
+		goto err_exit;
+	}
+
+	for (idx = 0; idx < opp_ct; idx++)
+		ddr_cdev->freq_table[idx] *= bus_width;
+
+	ret = icc_set_bw(ddr_cdev->icc_path, 0, freq_table[0]);
+	if (ret < 0) {
+		dev_err(dev, "Error placing DDR freq request. err:%d\n",
+			ret);
+		goto err_exit;
+	}
+
+	ddr_cdev->cdev = devm_thermal_of_cooling_device_register(
+					dev, np, cdev_name,
+					ddr_cdev, &ddr_cdev_ops);
+	if (IS_ERR(ddr_cdev->cdev)) {
+		ret = PTR_ERR(ddr_cdev->cdev);
+		dev_err(dev, "Cdev register failed for %s, ret:%d\n",
+			cdev_name, ret);
+		goto err_exit;
+	}
+	dev_dbg(dev, "Cooling device [%s] registered.\n", cdev_name);
+	dev_set_drvdata(dev, ddr_cdev);
+
+	return 0;
+err_exit:
+	icc_put(ddr_cdev->icc_path);
+
+	return ret;
+}
+
+static int ddr_cdev_remove(struct platform_device *pdev)
+{
+	struct ddr_cdev *ddr_cdev =
+		(struct ddr_cdev *)dev_get_drvdata(&pdev->dev);
+
+	if (ddr_cdev->icc_path) {
+		icc_set_bw(ddr_cdev->icc_path, 0, ddr_cdev->freq_table[0]);
+		icc_put(ddr_cdev->icc_path);
+		ddr_cdev->icc_path = NULL;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id ddr_cdev_match[] = {
+	{ .compatible = "qcom,ddr-cooling-device", },
+	{},
+};
+
+static struct platform_driver ddr_cdev_driver = {
+	.probe		= ddr_cdev_probe,
+	.remove         = ddr_cdev_remove,
+	.driver		= {
+		.name = KBUILD_MODNAME,
+		.of_match_table = ddr_cdev_match,
+	},
+};
+module_platform_driver(ddr_cdev_driver);
+MODULE_LICENSE("GPL");