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

Josef Gajdusek
2015-11-23T08:04:15Z

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@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@atx.name>");
+MODULE_DESCRIPTION("Sunxi THS driver");
+MODULE_LICENSE("GPL v2");
--
2.4.10