[PATCH v2 3/5] thermal: Add a driver for the Allwinner THS sensor

Josef Gajdusek atx at atx.name
Mon Nov 23 00:02:50 PST 2015


This patch adds support for the Sunxi thermal sensor on the Allwinner H3.
Should be easily extendable for the A33/A83T/... as they have similar but
not completely identical sensors.

Signed-off-by: Josef Gajdusek <atx at atx.name>
---
 drivers/thermal/Kconfig     |   7 +
 drivers/thermal/Makefile    |   1 +
 drivers/thermal/sun8i_ths.c | 365 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 373 insertions(+)
 create mode 100644 drivers/thermal/sun8i_ths.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index c463c89..2b41147 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -365,6 +365,13 @@ config INTEL_PCH_THERMAL
 	  Thermal reporting device will provide temperature reading,
 	  programmable trip points and other information.
 
+config SUN8I_THS
+	tristate "sun8i THS driver"
+	depends on MACH_SUN8I
+	depends on OF
+	help
+	  Enable this to support thermal reporting on some newer Allwinner SoCs.
+
 menu "Texas Instruments thermal drivers"
 depends on ARCH_HAS_BANDGAP || COMPILE_TEST
 source "drivers/thermal/ti-soc-thermal/Kconfig"
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index cfae6a6..227e1a1 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -48,3 +48,4 @@ obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra_soctherm.o
 obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
+obj-$(CONFIG_SUN8I_THS)		+= sun8i_ths.o
diff --git a/drivers/thermal/sun8i_ths.c b/drivers/thermal/sun8i_ths.c
new file mode 100644
index 0000000..2c976ac
--- /dev/null
+++ b/drivers/thermal/sun8i_ths.c
@@ -0,0 +1,365 @@
+/*
+ * Sunxi THS driver
+ *
+ * Copyright (C) 2015 Josef Gajdusek
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that 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/irq.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/printk.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define THS_H3_CTRL0			0x00
+#define THS_H3_CTRL1			0x04
+#define THS_H3_CDAT				0x14
+#define THS_H3_CTRL2			0x40
+#define THS_H3_INT_CTRL			0x44
+#define THS_H3_STAT				0x48
+#define THS_H3_ALARM_CTRL		0x50
+#define THS_H3_SHUTDOWN_CTRL	0x60
+#define THS_H3_FILTER			0x70
+#define THS_H3_CDATA			0x74
+#define THS_H3_DATA				0x80
+
+#define THS_H3_CTRL0_SENSOR_ACQ0_OFFS   0
+#define THS_H3_CTRL0_SENSOR_ACQ0(x) \
+	((x) << THS_H3_CTRL0_SENSOR_ACQ0_OFFS)
+#define THS_H3_CTRL1_ADC_CALI_EN_OFFS   17
+#define THS_H3_CTRL1_ADC_CALI_EN \
+	BIT(THS_H3_CTRL1_ADC_CALI_EN_OFFS)
+#define THS_H3_CTRL1_OP_BIAS_OFFS       20
+#define THS_H3_CTRL1_OP_BIAS(x) \
+	((x) << THS_H3_CTRL1_OP_BIAS_OFFS)
+#define THS_H3_CTRL2_SENSE_EN_OFFS      0
+#define THS_H3_CTRL2_SENSE_EN \
+	BIT(THS_H3_CTRL2_SENSE_EN_OFFS)
+#define THS_H3_CTRL2_SENSOR_ACQ1_OFFS   16
+#define THS_H3_CTRL2_SENSOR_ACQ1(x) \
+	((x) << THS_H3_CTRL2_SENSOR_ACQ1_OFFS)
+
+#define THS_H3_INT_CTRL_ALARM_INT_EN_OFFS       0
+#define THS_H3_INT_CTRL_ALARM_INT_EN \
+	BIT(THS_H3_INT_CTRL_ALARM_INT_EN_OFFS)
+#define THS_H3_INT_CTRL_SHUT_INT_EN_OFFS		4
+#define THS_H3_INT_CTRL_SHUT_INT_EN \
+	BIT(THS_H3_INT_CTRL_SHUT_INT_EN_OFFS)
+#define THS_H3_INT_CTRL_DATA_IRQ_EN_OFFS		8
+#define THS_H3_INT_CTRL_DATA_IRQ_EN \
+	BIT(THS_H3_INT_CTRL_DATA_IRQ_EN_OFFS)
+#define THS_H3_INT_CTRL_THERMAL_PER_OFFS		12
+#define THS_H3_INT_CTRL_THERMAL_PER(x) \
+	((x) << THS_H3_INT_CTRL_THERMAL_PER_OFFS)
+
+#define THS_H3_STAT_ALARM_INT_STS_OFFS  0
+#define THS_H3_STAT_ALARM_INT_STS \
+	BIT(THS_H3_STAT_ALARM_INT_STS_OFFS)
+#define THS_H3_STAT_SHUT_INT_STS_OFFS   4
+#define THS_H3_STAT_SHUT_INT_STS \
+	BIT(THS_H3_STAT_SHUT_INT_STS_OFFS)
+#define THS_H3_STAT_DATA_IRQ_STS_OFFS   8
+#define THS_H3_STAT_DATA_IRQ_STS \
+	BIT(THS_H3_STAT_DATA_IRQ_STS_OFFS)
+#define THS_H3_STAT_ALARM_OFF_STS_OFFS  12
+#define THS_H3_STAT_ALARM_OFF_STS \
+	BIT(THS_H3_STAT_ALARM_OFF_STS_OFFS)
+
+#define THS_H3_ALARM_CTRL_ALARM0_T_HYST_OFFS    0
+#define THS_H3_ALARM_CTRL_ALARM0_T_HYST(x) \
+	((x) << THS_H3_ALARM_CTRL_ALARM0_T_HYST_OFFS)
+#define THS_H3_ALARM_CTRL_ALARM0_T_HOT_OFFS     16
+#define THS_H3_ALARM_CTRL_ALARM0_T_HOT(x) \
+	((x) << THS_H3_ALARM_CTRL_ALARM0_T_HOT_OFFS)
+
+#define THS_H3_SHUTDOWN_CTRL_SHUT0_T_HOT_OFFS   16
+#define THS_H3_SHUTDOWN_CTRL_SHUT0_T_HOT(x) \
+	((x) << THS_H3_SHUTDOWN_CTRL_SHUT0_T_HOT_OFFS)
+
+#define THS_H3_FILTER_TYPE_OFFS 0
+#define THS_H3_FILTER_TYPE(x) \
+	((x) << THS_H3_FILTER_TYPE_OFFS)
+#define THS_H3_FILTER_EN_OFFS   2
+#define THS_H3_FILTER_EN \
+	BIT(THS_H3_FILTER_EN_OFFS)
+
+#define THS_H3_CTRL0_SENSOR_ACQ0_VALUE			0xff
+#define THS_H3_INT_CTRL_THERMAL_PER_VALUE		0x79
+#define THS_H3_FILTER_TYPE_VALUE				0x2
+#define THS_H3_CTRL2_SENSOR_ACQ1_VALUE			0x3f
+
+struct sun8i_ths_data {
+	struct sun8i_ths_type *type;
+	struct reset_control *reset;
+	struct clk *clk;
+	struct clk *busclk;
+	void __iomem *regs;
+	struct nvmem_cell *calcell;
+	struct platform_device *pdev;
+	struct thermal_zone_device *tzd;
+};
+
+struct sun8i_ths_type {
+	int (*init)(struct platform_device *, struct sun8i_ths_data *);
+	int (*get_temp)(struct sun8i_ths_data *, int *out);
+	void (*irq)(struct sun8i_ths_data *);
+	void (*deinit)(struct sun8i_ths_data *);
+};
+
+/* Formula and parameters from the Allwinner 3.4 kernel */
+static int sun8i_ths_reg_to_temperature(s32 reg, int divisor, int constant)
+{
+	return constant - (reg * 1000000) / divisor;
+}
+
+static int sun8i_ths_get_temp(void *_data, int *out)
+{
+	struct sun8i_ths_data *data = _data;
+
+	return data->type->get_temp(data, out);
+}
+
+static irqreturn_t sun8i_ths_irq_thread(int irq, void *_data)
+{
+	struct sun8i_ths_data *data = _data;
+
+	data->type->irq(data);
+	thermal_zone_device_update(data->tzd);
+
+	return IRQ_HANDLED;
+}
+
+static int sun8i_ths_h3_init(struct platform_device *pdev,
+			     struct sun8i_ths_data *data)
+{
+	int ret;
+	size_t callen;
+	s32 *caldata;
+
+	data->busclk = devm_clk_get(&pdev->dev, "ahb");
+	if (IS_ERR(data->busclk)) {
+		ret = PTR_ERR(data->busclk);
+		dev_err(&pdev->dev, "failed to get ahb clk: %d\n", ret);
+		return ret;
+	}
+
+	data->clk = devm_clk_get(&pdev->dev, "ths");
+	if (IS_ERR(data->clk)) {
+		ret = PTR_ERR(data->clk);
+		dev_err(&pdev->dev, "failed to get ths clk: %d\n", ret);
+		return ret;
+	}
+
+	data->reset = devm_reset_control_get(&pdev->dev, "ahb");
+	if (IS_ERR(data->reset)) {
+		ret = PTR_ERR(data->reset);
+		dev_err(&pdev->dev, "failed to get reset: %d\n", ret);
+		return ret;
+	}
+
+	if (data->calcell) {
+		caldata = nvmem_cell_read(data->calcell, &callen);
+		if (IS_ERR(caldata))
+			return PTR_ERR(caldata);
+		writel(be32_to_cpu(*caldata), data->regs + THS_H3_CDATA);
+		kfree(caldata);
+	}
+
+	ret = clk_prepare_enable(data->busclk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable bus clk: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(data->clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable ths clk: %d\n", ret);
+		goto err_disable_bus;
+	}
+
+	ret = reset_control_deassert(data->reset);
+	if (ret) {
+		dev_err(&pdev->dev, "reset deassert failed: %d\n", ret);
+		goto err_disable_ths;
+	}
+
+	/* The final sample period is calculated as follows:
+	 * (THERMAL_PER + 1) * 4096 / f_clk * 2^(FILTER_TYPE + 1)
+	 *
+	 * This results to about 1Hz with these settings.
+	 */
+	ret = clk_set_rate(data->clk, 4000000);
+	if (ret)
+		goto err_disable_ths;
+	writel(THS_H3_CTRL0_SENSOR_ACQ0(THS_H3_CTRL0_SENSOR_ACQ0_VALUE),
+	       data->regs + THS_H3_CTRL0);
+	writel(THS_H3_INT_CTRL_THERMAL_PER(THS_H3_INT_CTRL_THERMAL_PER_VALUE) |
+	       THS_H3_INT_CTRL_DATA_IRQ_EN,
+	       data->regs + THS_H3_INT_CTRL);
+	writel(THS_H3_FILTER_EN | THS_H3_FILTER_TYPE(THS_H3_FILTER_TYPE_VALUE),
+	       data->regs + THS_H3_FILTER);
+	writel(THS_H3_CTRL2_SENSOR_ACQ1(THS_H3_CTRL2_SENSOR_ACQ1_VALUE) |
+	       THS_H3_CTRL2_SENSE_EN,
+	       data->regs + THS_H3_CTRL2);
+	return 0;
+
+err_disable_ths:
+	clk_disable_unprepare(data->clk);
+err_disable_bus:
+	clk_disable_unprepare(data->busclk);
+
+	return ret;
+}
+
+static int sun8i_ths_h3_get_temp(struct sun8i_ths_data *data, int *out)
+{
+	int val = readl(data->regs + THS_H3_DATA);
+	*out = sun8i_ths_reg_to_temperature(val, 8253, 217000);
+	return 0;
+}
+
+static void sun8i_ths_h3_irq(struct sun8i_ths_data *data)
+{
+	writel(THS_H3_STAT_DATA_IRQ_STS |
+	       THS_H3_STAT_ALARM_INT_STS |
+	       THS_H3_STAT_ALARM_OFF_STS |
+	       THS_H3_STAT_SHUT_INT_STS,
+	       data->regs + THS_H3_STAT);
+}
+
+static void sun8i_ths_h3_deinit(struct sun8i_ths_data *data)
+{
+	reset_control_assert(data->reset);
+	clk_disable_unprepare(data->clk);
+	clk_disable_unprepare(data->busclk);
+}
+
+static const struct thermal_zone_of_device_ops sun8i_ths_thermal_ops = {
+	.get_temp = sun8i_ths_get_temp,
+};
+
+static const struct sun8i_ths_type sun8i_ths_device_h3 = {
+	.init = sun8i_ths_h3_init,
+	.get_temp = sun8i_ths_h3_get_temp,
+	.irq = sun8i_ths_h3_irq,
+	.deinit = sun8i_ths_h3_deinit,
+};
+
+static const struct of_device_id sun8i_ths_id_table[] = {
+	{
+		.compatible = "allwinner,sun8i-h3-ths",
+		.data = &sun8i_ths_device_h3,
+	},
+	{
+		/* sentinel */
+	},
+};
+MODULE_DEVICE_TABLE(of, sun8i_ths_id_table);
+
+static int sun8i_ths_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *match;
+	struct sun8i_ths_data *data;
+	struct resource *res;
+	int ret;
+	int irq;
+
+	match = of_match_node(sun8i_ths_id_table, np);
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->type = (struct sun8i_ths_type *)match->data;
+	data->pdev = pdev;
+
+	data->calcell = devm_nvmem_cell_get(&pdev->dev, "calibration");
+	if (IS_ERR(data->calcell)) {
+		if (PTR_ERR(data->calcell) == -EPROBE_DEFER)
+			return PTR_ERR(data->calcell);
+		data->calcell = NULL; /* No calibration register */
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	data->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(data->regs)) {
+		ret = PTR_ERR(data->regs);
+		dev_err(&pdev->dev,
+			"failed to ioremap THS registers: %d\n", ret);
+		return ret;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ: %d\n", irq);
+		return irq;
+	}
+
+	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+					sun8i_ths_irq_thread, IRQF_ONESHOT,
+					dev_name(&pdev->dev), data);
+	if (ret)
+		return ret;
+
+	ret = data->type->init(pdev, data);
+	if (ret)
+		return ret;
+
+	data->tzd = thermal_zone_of_sensor_register(&pdev->dev, 0, data,
+						    &sun8i_ths_thermal_ops);
+	if (IS_ERR(data->tzd)) {
+		ret = PTR_ERR(data->tzd);
+		dev_err(&pdev->dev, "failed to register thermal zone: %d\n",
+			ret);
+		goto err_deinit;
+	}
+
+	platform_set_drvdata(pdev, data);
+	return 0;
+
+err_deinit:
+	data->type->deinit(data);
+	return ret;
+}
+
+static int sun8i_ths_remove(struct platform_device *pdev)
+{
+	struct sun8i_ths_data *data = platform_get_drvdata(pdev);
+
+	thermal_zone_of_sensor_unregister(&pdev->dev, data->tzd);
+	data->type->deinit(data);
+	return 0;
+}
+
+static struct platform_driver sun8i_ths_driver = {
+	.probe = sun8i_ths_probe,
+	.remove = sun8i_ths_remove,
+	.driver = {
+		.name = "sun8i_ths",
+		.of_match_table = sun8i_ths_id_table,
+	},
+};
+
+module_platform_driver(sun8i_ths_driver);
+
+MODULE_AUTHOR("Josef Gajdusek <atx at atx.name>");
+MODULE_DESCRIPTION("Sunxi THS driver");
+MODULE_LICENSE("GPL v2");
-- 
2.4.10




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