path: root/drivers/thermal/sun9i_thermal.c

/*
 * Copyright (c) 2016, Theobroma Systems Design und Consulting GmbH
 * Dr. Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/thermal.h>
#include <linux/hwmon.h>
#include <linux/mfd/syscon.h>
#include <linux/pinctrl/consumer.h>



/**
 * struct sun9i_thermal_sensor - hold the information of thermal sensor
 * @thermal:  pointer to the platform/configuration data
 * @tzd: pointer to a thermal zone
 * @id: identifier of the thermal sensor
 */
struct sun9i_thermal_sensor {
	struct sun9i_thermal_data *thermal;
	struct thermal_zone_device *tzd;
	const char* name;
	int id;
};

/**
 * struct sun9i_thermal_data - hold the private data of thermal driver
 * @pdev: platform device of thermal
 * @reset: the reset controller of tsadc
 * @sensors[SOC_MAX_SENSORS]: the thermal sensor
 * @mclk: the controller clock (GPADC) is divided down from the exteral 24MHz
 * @hclk: the AHB bus clock (for register accesses)
 * @grf: the general register file will be used to do static set by software
 * @regs: the base address of tsadc controller
 */
struct sun9i_thermal_data {
	struct platform_device *pdev;
	struct reset_control *reset;

	struct sun9i_thermal_sensor *sensors;
	u32 num_channels;

	struct clk *hclk;
	struct clk *mclk;

	void __iomem *regs;

	/*
	 * Conversion parameters from the device-tree for the following
	 * conversion function:
	 *   tCELSIUS = ((MULTIPLIER * data) + OFFSET) / DIVISOR
	 *
	 * These should be configured through the DTS keys:
	 *   allwinner,sun9i-tsc-multiplier
	 *   allwinner,sun9i-tsc-offset
	 *   allwinner,sun9i-tsc-divisor
	 */
	s32  multiplier;
	s32  offset;
	s32  divisor;
};

static const struct of_device_id of_sun9i_thermal_match[] = {
	{
		.compatible = "allwinner,sun9i-tsc",
	},
	{ /* end */ },
};
MODULE_DEVICE_TABLE(of, of_sun9i_thermal_match);

#if 0
static void
rockchip_thermal_toggle_sensor(struct rockchip_thermal_sensor *sensor, bool on)
{
	struct thermal_zone_device *tzd = sensor->tzd;

	tzd->ops->set_mode(tzd,
		on ? THERMAL_DEVICE_ENABLED : THERMAL_DEVICE_DISABLED);
}

static irqreturn_t rockchip_thermal_alarm_irq_thread(int irq, void *dev)
{
	struct rockchip_thermal_data *thermal = dev;
	int i;

	dev_dbg(&thermal->pdev->dev, "thermal alarm\n");

	thermal->chip->irq_ack(thermal->regs);

	for (i = 0; i < thermal->chip->chn_num; i++)
		thermal_zone_device_update(thermal->sensors[i].tzd);

	return IRQ_HANDLED;
}
#endif

#define THSx_DATA(ch)   (0x40 + (ch) * 0x4)

static int sun9i_thermal_get_temp(void *_sensor, int *out_temp)
{
	struct sun9i_thermal_sensor *sensor = _sensor;
	struct sun9i_thermal_data *thermal = sensor->thermal;
	s32 val;

	val = readl_relaxed(thermal->regs + THSx_DATA(sensor->id));
	*out_temp = (thermal->multiplier * val + thermal->offset) / (thermal->divisor);
	dev_dbg(&thermal->pdev->dev, "sensor %d - temp %d (raw 0x%x)\n",
		sensor->id, *out_temp, val);

	return 0;
}

static const struct thermal_zone_of_device_ops sun9i_of_thermal_ops = {
	.get_temp = sun9i_thermal_get_temp,
};

static int sun9i_configure_from_dt(struct device *dev,
				   struct device_node *node,
				   struct sun9i_thermal_data *thermal)
{
	u32 num_channels;
	int i;

	if (of_property_read_u32(node, "allwinner,sun9i-tsc-channels", &num_channels)) {
		dev_err(dev, "missing sun9i-tsc-channels (number of channels) property\n");
		return -EINVAL;
	}

	thermal->sensors = devm_kzalloc(dev, sizeof(struct sun9i_thermal_sensor) * num_channels, GFP_KERNEL);
	thermal->num_channels = num_channels;

	for (i = 0; i < num_channels; ++i)
		if (of_property_read_string_index(node, "allwinner,sun9i-tsc-name", i,
						  &thermal->sensors[i].name)) {
			dev_err(dev, "missing allwinner,sun9i-tsc-name property\n");
			return -EINVAL;
		}

	if (of_property_read_s32(node, "allwinner,sun9i-tsc-multiplier", &thermal->multiplier)) {
		dev_warn(dev, "missing sun9i-tsc-multiplier, assuming 1\n");
		thermal->multiplier = 1;
	}

	if (of_property_read_s32(node, "allwinner,sun9i-tsc-offset", &thermal->offset)) {
		dev_warn(dev, "missing sun9i-tsc-offset, assuming 0\n");
		thermal->offset = 0;
	}

	if (of_property_read_s32(node, "allwinner,sun9i-tsc-divisor", &thermal->divisor)) {
		dev_warn(dev, "missing sun9i-tsc-divisor, assuming 1\n");
		thermal->divisor = 1;
	}

	return 0;
}

static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
			 char *buf)
{
	struct sun9i_thermal_sensor *ts = dev_get_drvdata(dev);
	int temp;
	int error;

	error = sun9i_thermal_get_temp(ts, &temp);
	if (error)
		return error;

	return sprintf(buf, "%d\n", temp);
}

static ssize_t show_temp_label(struct device *dev,
			      struct device_attribute *devattr, char *buf)
{
	struct sun9i_thermal_sensor *ts = dev_get_drvdata(dev);
	return sprintf(buf, "SoC temperature (%s)\n", ts->name);
}

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL);

static struct attribute *sun9i_ts_attrs[] = {
	&dev_attr_temp1_input.attr,
	&dev_attr_temp1_label.attr,
	NULL
};
ATTRIBUTE_GROUPS(sun9i_ts);

static int
sun9i_thermal_register_sensor(struct platform_device *pdev,
			      struct sun9i_thermal_data *thermal,
			      int id)
{
	int error;
	struct sun9i_thermal_sensor *sensor = &thermal->sensors[id];
	struct device *hwmon;

	printk("sun9i_thermal_register_sensor entered for id %d\n", id);

	sensor->thermal = thermal;
	sensor->id = id;
	sensor->tzd = devm_thermal_zone_of_sensor_register(&pdev->dev, id,
							   sensor, &sun9i_of_thermal_ops);
	if (IS_ERR(sensor->tzd)) {
		error = PTR_ERR(sensor->tzd);
		dev_err(&pdev->dev, "failed to register sensor %d: %d\n",
			id, error);
		return error;
	}

	/*
	 * The thermal core does not register hwmon devices for DT-based
	 * thermal zone sensors, such as this one.
	 */
	printk("registering %s with hwmon\n", sensor->name);
	hwmon = devm_hwmon_device_register_with_groups(&pdev->dev, sensor->name,
						       sensor, sun9i_ts_groups);
	if (IS_ERR(hwmon)) {
		dev_err(&pdev->dev, "failed to register sensor %s in hwmon: %ld\n",
			sensor->name, PTR_ERR(hwmon));
		return PTR_ERR(hwmon);
	}

	return 0;
}

#if 1
/**
 * Reset TSADC Controller, reset all tsadc registers.
 */
static void sun9i_thermal_reset_controller(struct reset_control *reset)
{
	reset_control_assert(reset);
	usleep_range(10, 20);
	reset_control_deassert(reset);
}
#endif

static int sun9i_thermal_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct sun9i_thermal_data *thermal;
	const struct of_device_id *match;
	struct resource *res;
	int irq;
	int i;
	int error;

	match = of_match_node(of_sun9i_thermal_match, np);
	if (!match)
		return -ENXIO;

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_err(&pdev->dev, "no irq resource?\n");
		return -EINVAL;
	}

	thermal = devm_kzalloc(&pdev->dev, sizeof(struct sun9i_thermal_data),
			       GFP_KERNEL);
	if (!thermal)
		return -ENOMEM;

	thermal->pdev = pdev;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	thermal->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(thermal->regs))
		return PTR_ERR(thermal->regs);

	thermal->reset = devm_reset_control_get(&pdev->dev, NULL);
	if (IS_ERR(thermal->reset)) {
		error = PTR_ERR(thermal->reset);
		dev_err(&pdev->dev, "failed to get tsadc reset: %d\n", error);
		return error;
	}

	thermal->hclk = devm_clk_get(&pdev->dev, "ahb");
	if (IS_ERR(thermal->hclk)) {
		error = PTR_ERR(thermal->hclk);
		dev_err(&pdev->dev, "failed to get sun9i_tsc AHB clock: %d\n", error);
		return error;
	}

	thermal->mclk = devm_clk_get(&pdev->dev, "mod");
	if (IS_ERR(thermal->mclk)) {
		error = PTR_ERR(thermal->mclk);
		dev_err(&pdev->dev, "failed to get sun9i_tsc module clock: %d\n",
			error);
		return error;
	}

	error = clk_prepare_enable(thermal->hclk);
	if (error) {
		dev_err(&pdev->dev, "failed to enable pclk: %d\n", error);
		return error;
	}

	/* Ensure that our parent clock is slow enough */
	error = sun9i_configure_from_dt(&pdev->dev, np, thermal);
	if (error) {
		dev_err(&pdev->dev, "failed to parse device tree data: %d\n",
			error);
		return error;
	}

	//	clk_set_rate(thermal->mclk, 1000000);
	error = clk_prepare_enable(thermal->mclk);
	if (error) {
		dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
			error);
		goto err_disable_hclk;
	}

	sun9i_thermal_reset_controller(thermal->reset);

#if 0
	thermal->chip->initialize(thermal->grf, thermal->regs,
				  thermal->tshut_polarity);
#endif

	for (i = 0; i < thermal->num_channels; i++) {
		error = sun9i_thermal_register_sensor(pdev, thermal, i);

		if (error) {
			dev_err(&pdev->dev,
				"failed to register sensor[%d] : error = %d\n",
				i, error);
			goto err_disable_mclk;
		}
	}

#if 0
	error = devm_request_threaded_irq(&pdev->dev, irq, NULL,
					  &rockchip_thermal_alarm_irq_thread,
					  IRQF_ONESHOT,
					  "rockchip_thermal", thermal);
	if (error) {
		dev_err(&pdev->dev,
			"failed to request tsadc irq: %d\n", error);
		goto err_disable_pclk;
	}
#endif

	//	thermal->chip->control(thermal->regs, true);
	writel_relaxed(0x4000f, thermal->regs);

#if 0
	for (i = 0; i < thermal->chip->num_channels; i++)
		rockchip_thermal_toggle_sensor(&thermal->sensors[i], true);
#endif

	platform_set_drvdata(pdev, thermal);

	return 0;

err_disable_mclk:
	clk_disable_unprepare(thermal->mclk);
err_disable_hclk:
	clk_disable_unprepare(thermal->hclk);

	return error;
}

static int sun9i_thermal_remove(struct platform_device *pdev)
{
#if 0
	struct rockchip_thermal_data *thermal = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < thermal->chip->chn_num; i++) {
		struct rockchip_thermal_sensor *sensor = &thermal->sensors[i];

		rockchip_thermal_toggle_sensor(sensor, false);
	}

	thermal->chip->control(thermal->regs, false);

	clk_disable_unprepare(thermal->pclk);
	clk_disable_unprepare(thermal->clk);
#endif

	return 0;
}

static int __maybe_unused sun9i_thermal_suspend(struct device *dev)
{
#if 0
	struct platform_device *pdev = to_platform_device(dev);
	struct rockchip_thermal_data *thermal = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < thermal->chip->chn_num; i++)
		rockchip_thermal_toggle_sensor(&thermal->sensors[i], false);

	thermal->chip->control(thermal->regs, false);

	clk_disable(thermal->pclk);
	clk_disable(thermal->clk);

	pinctrl_pm_select_sleep_state(dev);
#endif

	return 0;
}

static int __maybe_unused sun9i_thermal_resume(struct device *dev)
{
#if 0
	struct platform_device *pdev = to_platform_device(dev);
	struct rockchip_thermal_data *thermal = platform_get_drvdata(pdev);
	int i;
	int error;

	error = clk_enable(thermal->clk);
	if (error)
		return error;

	error = clk_enable(thermal->pclk);
	if (error) {
		clk_disable(thermal->clk);
		return error;
	}

	rockchip_thermal_reset_controller(thermal->reset);

	thermal->chip->initialize(thermal->grf, thermal->regs,
				  thermal->tshut_polarity);

	for (i = 0; i < thermal->chip->chn_num; i++) {
		int id = thermal->sensors[i].id;

		thermal->chip->set_tshut_mode(id, thermal->regs,
					      thermal->tshut_mode);
		thermal->chip->set_tshut_temp(thermal->chip->table,
					      id, thermal->regs,
					      thermal->tshut_temp);
	}

	thermal->chip->control(thermal->regs, true);

	for (i = 0; i < thermal->chip->chn_num; i++)
		rockchip_thermal_toggle_sensor(&thermal->sensors[i], true);

	pinctrl_pm_select_default_state(dev);
#endif

	return 0;
}

static SIMPLE_DEV_PM_OPS(sun9i_thermal_pm_ops,
			 sun9i_thermal_suspend, sun9i_thermal_resume);

static struct platform_driver sun9i_thermal_driver = {
	.driver = {
		.name = "allwinner-sun9i-thermal",
		.pm = &sun9i_thermal_pm_ops,
		.of_match_table = of_sun9i_thermal_match,
	},
	.probe = sun9i_thermal_probe,
	.remove = sun9i_thermal_remove,
};

module_platform_driver(sun9i_thermal_driver);

MODULE_DESCRIPTION("Allwinner A80 thermal sensor controller driver");
MODULE_AUTHOR("Theobroma Systems GmbH");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:allwinner-thermal");