[PATCH v2 02/14] thermal: sun8i_ths: Add support for the thermal sensor on Allwinner H3

megous-5qf/QAjKc83QT0dZR+AlfA
2016-06-25T03:44:59Z

From: Ondrej Jirman <megous-5qf/QAjKc83QT0dZR+AlfA@public.gmane.org>

This patch adds support for the sun8i thermal sensor on
Allwinner H3 SoC.

Signed-off-by: Ondřej Jirman <megous-5qf/QAjKc83QT0dZR+AlfA@public.gmane.org>
---
v2:
- removed incorrect use of SID driver in sun8i_ths
- read calibration data directly from iomem
- better explanation for the thermal sensor driver
- dt documentation fixes
- dropped unncecessary macros and init code reorganization
- moved resource aquisition from init to probe function
- deassert reset after clock rate is set, not before
- enable irq after all other registers are configured
---
drivers/thermal/Kconfig | 7 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/sun8i_ths.c | 260 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 268 insertions(+)
create mode 100644 drivers/thermal/sun8i_ths.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 2d702ca..d3209d9 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -351,6 +351,13 @@ config MTK_THERMAL
Enable this option if you want to have support for thermal management
controller present in Mediatek SoCs

+config SUN8I_THS
+ tristate "Thermal sensor driver for Allwinner H3"
+ 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
depends on HAS_IOMEM
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 10b07c1..7261ee8 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -51,3 +51,4 @@ obj-$(CONFIG_TEGRA_SOCTHERM) += tegra/
obj-$(CONFIG_HISI_THERMAL) += hisi_thermal.o
obj-$(CONFIG_MTK_THERMAL) += mtk_thermal.o
obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.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..9ba0f96
--- /dev/null
+++ b/drivers/thermal/sun8i_ths.c
@@ -0,0 +1,260 @@
+/*
+ * Thermal sensor driver for Allwinner H3 SoC
+ *
+ * Copyright (C) 2016 Ondřej Jirman
+ * Based on the work of Josef Gajdusek <atx-MwjtXicnQwU@public.gmane.org>
+ *
+ * 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/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+#include <linux/printk.h>
+
+#define THS_H3_CTRL0 0x00
+#define THS_H3_CTRL2 0x40
+#define THS_H3_INT_CTRL 0x44
+#define THS_H3_STAT 0x48
+#define THS_H3_FILTER 0x70
+#define THS_H3_CDATA 0x74
+#define THS_H3_DATA 0x80
+
+#define THS_H3_CTRL0_SENSOR_ACQ0(x) (x)
+#define THS_H3_CTRL2_SENSE_EN BIT(0)
+#define THS_H3_CTRL2_SENSOR_ACQ1(x) ((x) << 16)
+#define THS_H3_INT_CTRL_DATA_IRQ_EN BIT(8)
+#define THS_H3_INT_CTRL_THERMAL_PER(x) ((x) << 12)
+#define THS_H3_STAT_DATA_IRQ_STS BIT(8)
+#define THS_H3_FILTER_TYPE(x) ((x) << 0)
+#define THS_H3_FILTER_EN BIT(2)
+
+#define THS_H3_CLK_IN 40000000 /* Hz */
+#define THS_H3_DATA_PERIOD 330 /* ms */
+
+#define THS_H3_FILTER_TYPE_VALUE 2 /* average over 2^(n+1) samples */
+#define THS_H3_FILTER_DIV (1 << (THS_H3_FILTER_TYPE_VALUE + 1))
+#define THS_H3_INT_CTRL_THERMAL_PER_VALUE \
+ (THS_H3_DATA_PERIOD * (THS_H3_CLK_IN / 1000) / THS_H3_FILTER_DIV / 4096 - 1)
+#define THS_H3_CTRL0_SENSOR_ACQ0_VALUE 0x3f /* 16us */
+#define THS_H3_CTRL2_SENSOR_ACQ1_VALUE 0x3f
+
+struct sun8i_ths_data {
+ struct reset_control *reset;
+ struct clk *clk;
+ struct clk *busclk;
+ void __iomem *regs;
+ void __iomem *calreg;
+ struct thermal_zone_device *tzd;
+ u32 temp;
+};
+
+static int sun8i_ths_get_temp(void *_data, int *out)
+{
+ struct sun8i_ths_data *data = _data;
+
+ if (data->temp == 0)
+ return -EINVAL;
+
+ /* Formula and parameters from the Allwinner 3.4 kernel */
+ *out = 217000 - (int)((data->temp * 1000000) / 8253);
+ return 0;
+}
+
+static irqreturn_t sun8i_ths_irq_thread(int irq, void *_data)
+{
+ struct sun8i_ths_data *data = _data;
+
+ writel(THS_H3_STAT_DATA_IRQ_STS, data->regs + THS_H3_STAT);
+
+ data->temp = readl(data->regs + THS_H3_DATA);
+ if (data->temp)
+ thermal_zone_device_update(data->tzd);
+
+ return IRQ_HANDLED;
+}
+
+static void sun8i_ths_h3_init(struct sun8i_ths_data *data)
+{
+ u32 caldata;
+
+ caldata = readl(data->calreg) & 0xfff;
+ if (caldata != 0)
+ writel(caldata, data->regs + THS_H3_CDATA);
+
+ writel(THS_H3_CTRL0_SENSOR_ACQ0(THS_H3_CTRL0_SENSOR_ACQ0_VALUE),
+ data->regs + THS_H3_CTRL0);
+ 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);
+ 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);
+}
+
+static const struct thermal_zone_of_device_ops sun8i_ths_thermal_ops = {
+ .get_temp = sun8i_ths_get_temp,
+};
+
+static int sun8i_ths_probe(struct platform_device *pdev)
+{
+ struct sun8i_ths_data *data;
+ struct resource *res;
+ int ret;
+ int irq;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no memory resources defined\n");
+ return -EINVAL;
+ }
+
+ 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;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res) {
+ dev_err(&pdev->dev, "no calibration data memory resource defined\n");
+ return -EINVAL;
+ }
+
+ data->calreg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(data->calreg)) {
+ ret = PTR_ERR(data->calreg);
+ 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;
+
+ 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;
+ }
+
+ 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 = clk_set_rate(data->clk, THS_H3_CLK_IN);
+ if (ret)
+ goto err_disable_ths;
+
+ ret = reset_control_deassert(data->reset);
+ if (ret) {
+ dev_err(&pdev->dev, "reset deassert failed: %d\n", ret);
+ goto err_disable_ths;
+ }
+
+ sun8i_ths_h3_init(data);
+
+ 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_assert_reset;
+ }
+
+ platform_set_drvdata(pdev, data);
+ return 0;
+
+err_assert_reset:
+ reset_control_assert(data->reset);
+err_disable_ths:
+ clk_disable_unprepare(data->clk);
+err_disable_bus:
+ clk_disable_unprepare(data->busclk);
+ 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);
+ reset_control_assert(data->reset);
+ clk_disable_unprepare(data->clk);
+ clk_disable_unprepare(data->busclk);
+ return 0;
+}
+
+static const struct of_device_id sun8i_ths_id_table[] = {
+ { .compatible = "allwinner,sun8i-h3-ths", },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, sun8i_ths_id_table);
+
+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("Ondřej Jirman <megous-5qf/QAjKc83QT0dZR+AlfA@public.gmane.org>");
+MODULE_DESCRIPTION("Thermal sensor driver for Allwinner H3 SoC");
+MODULE_LICENSE("GPL v2");
--
2.9.0