[PATCH v4 01/11] thermal: sun8i: add thermal driver for h6

Yangtao Li
2019-06-23T16:43:02Z

This patch adds the support for allwinner thermal sensor, within
allwinner SoC. It will register sensors for thermal framework
and use device tree to bind cooling device.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
MAINTAINERS | 7 +
drivers/thermal/Kconfig | 14 ++
drivers/thermal/Makefile | 1 +
drivers/thermal/sun8i_thermal.c | 405 ++++++++++++++++++++++++++++++++
4 files changed, 427 insertions(+)
create mode 100644 drivers/thermal/sun8i_thermal.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 36a84614d6c3..67e7fcfaded2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -674,6 +674,13 @@ L: linux-crypto@vger.kernel.org
S: Maintained
F: drivers/crypto/sunxi-ss/

+ALLWINNER THERMAL DRIVER
+M: Yangtao Li <tiny.windzz@gmail.com>
+L: linux-pm@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
+F: drivers/thermal/sun8i_thermal.c
+
ALLWINNER VPU DRIVER
M: Maxime Ripard <maxime.ripard@bootlin.com>
M: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 9966364a6deb..f8b73b32b92d 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -262,6 +262,20 @@ config SPEAR_THERMAL
Enable this to plug the SPEAr thermal sensor driver into the Linux
thermal framework.

+config SUN8I_THERMAL
+ tristate "Allwinner sun8i thermal driver"
+ depends on ARCH_SUNXI || COMPILE_TEST
+ depends on HAS_IOMEM
+ depends on NVMEM
+ depends on OF
+ depends on RESET_CONTROLLER
+ help
+ Support for the sun8i thermal sensor driver into the Linux thermal
+ framework.
+
+ To compile this driver as a module, choose M here: the
+ module will be called sun8i-thermal.
+
config ROCKCHIP_THERMAL
tristate "Rockchip thermal driver"
depends on ARCH_ROCKCHIP || COMPILE_TEST
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 74a37c7f847a..fa6f8b206281 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
obj-y += broadcom/
obj-$(CONFIG_THERMAL_MMIO) += thermal_mmio.o
obj-$(CONFIG_SPEAR_THERMAL) += spear_thermal.o
+obj-$(CONFIG_SUN8I_THERMAL) += sun8i_thermal.o
obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o
obj-$(CONFIG_RCAR_THERMAL) += rcar_thermal.o
obj-$(CONFIG_RCAR_GEN3_THERMAL) += rcar_gen3_thermal.o
diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
new file mode 100644
index 000000000000..d6918c62682b
--- /dev/null
+++ b/drivers/thermal/sun8i_thermal.c
@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Thermal sensor driver for Allwinner SOC
+ * Copyright (C) 2019 Yangtao Li
+ *
+ * Based on the work of Icenowy Zheng <icenowy@aosc.io>
+ * Based on the work of Ondrej Jirman <megous@megous.com>
+ * Based on the work of Josef Gajdusek <atx@atx.name>
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define MAX_SENSOR_NUM 4
+
+#define SUN50I_H6_SENSOR_NUM 2
+#define SUN50I_H6_OFFSET -2794
+#define SUN50I_H6_SCALE -67
+
+#define FT_TEMP_MASK GENMASK(11, 0)
+#define TEMP_CALIB_MASK GENMASK(11, 0)
+#define TEMP_TO_REG 672
+#define CALIBRATE_DEFAULT 0x800
+
+#define SUN50I_THS_CTRL0 0x00
+#define SUN50I_H6_THS_ENABLE 0x04
+#define SUN50I_H6_THS_PC 0x08
+#define SUN50I_H6_THS_DIC 0x10
+#define SUN50I_H6_THS_DIS 0x20
+#define SUN50I_H6_THS_MFC 0x30
+#define SUN50I_H6_THS_TEMP_CALIB 0xa0
+#define SUN50I_H6_THS_TEMP_DATA 0xc0
+
+#define SUN50I_THS_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16)
+#define SUN50I_THS_FILTER_EN BIT(2)
+#define SUN50I_THS_FILTER_TYPE(x) (GENMASK(1, 0) & (x))
+#define SUN50I_H6_THS_PC_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12)
+#define SUN50I_H6_THS_DATA_IRQ_STS(x) BIT(x)
+
+/* millidegree celsius */
+#define SUN50I_H6_FT_DEVIATION 7000
+
+struct ths_device;
+
+struct tsensor {
+ struct ths_device *tmdev;
+ struct thermal_zone_device *tzd;
+ int id;
+};
+
+struct ths_device {
+ struct device *dev;
+ struct regmap *regmap;
+ struct reset_control *reset;
+ struct clk *bus_clk;
+ struct tsensor sensor[MAX_SENSOR_NUM];
+};
+
+/* Temp Unit: millidegree Celsius */
+static int sun8i_ths_reg2temp(struct ths_device *tmdev,
+ int reg)
+{
+ return (reg + SUN50I_H6_OFFSET) * SUN50I_H6_SCALE;
+}
+
+static int sun8i_ths_get_temp(void *data, int *temp)
+{
+ struct tsensor *s = data;
+ struct ths_device *tmdev = s->tmdev;
+ int val;
+
+ regmap_read(tmdev->regmap, SUN50I_H6_THS_TEMP_DATA +
+ 0x4 * s->id, &val);
+
+ /* ths have no data yet */
+ if (!val)
+ return -EBUSY;
+
+ *temp = sun8i_ths_reg2temp(tmdev, val);
+ /*
+ * XX - According to the original sdk, there are some platforms(rarely)
+ * that add a fixed offset value after calculating the temperature
+ * value. We can't simply put it on the formula for calculating the
+ * temperature above, because the formula for calculating the
+ * temperature above is also used when the sensor is calibrated. If
+ * do this, the correct calibration formula is hard to know.
+ */
+ *temp += SUN50I_H6_FT_DEVIATION;
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops ths_ops = {
+ .get_temp = sun8i_ths_get_temp,
+};
+
+static const struct regmap_config config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .fast_io = true,
+};
+
+static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
+{
+ struct ths_device *tmdev = data;
+ int i, state;
+
+ regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
+
+ for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
+
+ if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
+ /* clear data irq pending */
+ regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
+ SUN50I_H6_THS_DATA_IRQ_STS(i));
+
+ thermal_zone_device_update(tmdev->sensor[i].tzd,
+ THERMAL_EVENT_UNSPECIFIED);
+ }
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int sun50i_ths_calibrate(struct ths_device *tmdev)
+{
+ struct nvmem_cell *calcell;
+ struct device *dev = tmdev->dev;
+ u16 *caldata;
+ size_t callen;
+ int ft_temp;
+ int i, ret = 0;
+
+ calcell = devm_nvmem_cell_get(dev, "calib");
+ if (IS_ERR(calcell)) {
+ if (PTR_ERR(calcell) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ /*
+ * Even if the external calibration data stored in sid is
+ * not accessible, the THS hardware can still work, although
+ * the data won't be so accurate.
+ *
+ * The default value of calibration register is 0x800 for
+ * every sensor, and the calibration value is usually 0x7xx
+ * or 0x8xx, so they won't be away from the default value
+ * for a lot.
+ *
+ * So here we do not return error if the calibartion data is
+ * not available, except the probe needs deferring.
+ */
+ goto out;
+ }
+
+ caldata = nvmem_cell_read(calcell, &callen);
+ if (IS_ERR(caldata)) {
+ ret = PTR_ERR(caldata);
+ goto out;
+ }
+
+ if (!caldata[0] || callen < 2 + 2 * SUN50I_H6_SENSOR_NUM) {
+ ret = -EINVAL;
+ goto out_free;
+ }
+
+ /*
+ * efuse layout:
+ *
+ * 0 11 16 32
+ * +-------+-------+-------+
+ * |temp| |sensor0|sensor1|
+ * +-------+-------+-------+
+ *
+ * The calibration data on the H6 is the ambient temperature and
+ * sensor values that are filled during the factory test stage.
+ *
+ * The unit of stored FT temperature is 0.1 degreee celusis.
+ * Through the stored ambient temperature and the data read
+ * by the sensor, after a certain calculation, the calibration
+ * value to be compensated can be obtained.
+ */
+ ft_temp = caldata[0] & FT_TEMP_MASK;
+
+ for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
+ int reg = (int)caldata[i + 1];
+ int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
+ int delta, cdata, calib_offest;
+
+ /*
+ * To calculate the calibration value:
+ *
+ * X(in Celsius) = Ts - ft_temp
+ * delta = X * 10000 / TEMP_TO_REG
+ * cdata = CALIBRATE_DEFAULT - delta
+ *
+ * cdata: calibration value
+ */
+ delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
+ cdata = CALIBRATE_DEFAULT - delta;
+ if (cdata & ~TEMP_CALIB_MASK) {
+ /*
+ * Calibration value more than 12-bit, but calibration
+ * register is 12-bit. In this case, ths hardware can
+ * still work without calibration, although the data
+ * won't be so accurate.
+ */
+ dev_warn(dev, "sensor%d is not calibrated.\n", i);
+
+ continue;
+ }
+
+ calib_offest = SUN50I_H6_THS_TEMP_CALIB + (i / 2) * 0x4;
+
+ if (i % 2) {
+ int val;
+
+ regmap_read(tmdev->regmap, calib_offest, &val);
+ val = (val & TEMP_CALIB_MASK) | (cdata << 16);
+ regmap_write(tmdev->regmap, calib_offest, val);
+ } else {
+ regmap_write(tmdev->regmap, calib_offest, cdata);
+ }
+ }
+
+out_free:
+ kfree(caldata);
+out:
+ return ret;
+}
+
+static int sun8i_ths_resource_init(struct ths_device *tmdev)
+{
+ struct device *dev = tmdev->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *mem;
+ void __iomem *base;
+ int ret;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
+ if (IS_ERR(tmdev->regmap))
+ return PTR_ERR(tmdev->regmap);
+
+ tmdev->reset = devm_reset_control_get(dev, 0);
+ if (IS_ERR(tmdev->reset))
+ return PTR_ERR(tmdev->reset);
+
+ tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
+ if (IS_ERR(tmdev->bus_clk))
+ return PTR_ERR(tmdev->bus_clk);
+
+ ret = reset_control_deassert(tmdev->reset);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(tmdev->bus_clk);
+ if (ret)
+ goto assert_reset;
+
+ ret = sun50i_ths_calibrate(tmdev);
+ if (ret)
+ goto bus_disable;
+
+ return 0;
+
+bus_disable:
+ clk_disable_unprepare(tmdev->bus_clk);
+assert_reset:
+ reset_control_assert(tmdev->reset);
+
+ return ret;
+}
+
+static int sun50i_thermal_init(struct ths_device *tmdev)
+{
+ int val;
+
+ /*
+ * clkin = 24MHz
+ * T acquire = clkin / (x + 1)
+ * = 20us
+ */
+ regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
+ SUN50I_THS_CTRL0_T_ACQ(479));
+ /* average over 4 samples */
+ regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
+ SUN50I_THS_FILTER_EN |
+ SUN50I_THS_FILTER_TYPE(1));
+ /* period = (x + 1) * 4096 / clkin; ~10ms */
+ regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
+ SUN50I_H6_THS_PC_TEMP_PERIOD(58));
+ /* enable sensor */
+ val = GENMASK(SUN50I_H6_SENSOR_NUM - 1, 0);
+ regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
+ /* thermal data interrupt enable */
+ val = GENMASK(SUN50I_H6_SENSOR_NUM - 1, 0);
+ regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
+
+ return 0;
+}
+
+static int sun8i_ths_register(struct ths_device *tmdev)
+{
+ struct thermal_zone_device *tzd;
+ int i;
+
+ for (i = 0; i < SUN50I_H6_SENSOR_NUM; i++) {
+ tmdev->sensor[i].tmdev = tmdev;
+ tmdev->sensor[i].id = i;
+ tmdev->sensor[i].tzd =
+ devm_thermal_zone_of_sensor_register(tmdev->dev,
+ i,
+ &tmdev->sensor[i],
+ &ths_ops);
+ if (IS_ERR(tmdev->sensor[i].tzd))
+ return PTR_ERR(tzd);
+ }
+
+ return 0;
+}
+
+static int sun8i_ths_probe(struct platform_device *pdev)
+{
+ struct ths_device *tmdev;
+ struct device *dev = &pdev->dev;
+ int ret, irq;
+
+ tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
+ if (!tmdev)
+ return -ENOMEM;
+
+ tmdev->dev = dev;
+ platform_set_drvdata(pdev, tmdev);
+
+ ret = sun8i_ths_resource_init(tmdev);
+ if (ret)
+ return ret;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ ret = sun50i_thermal_init(tmdev);
+ if (ret)
+ return ret;
+
+ ret = sun8i_ths_register(tmdev);
+ if (ret)
+ return ret;
+
+ /*
+ * Avoid entering the interrupt handler, the thermal device is not
+ * registered yet, we deffer the registration of the interrupt to
+ * the end.
+ */
+ ret = devm_request_threaded_irq(dev, irq, NULL,
+ sun50i_h6_irq_thread,
+ IRQF_ONESHOT, "ths", tmdev);
+ if (ret)
+ return ret;
+
+ return ret;
+}
+
+static int sun8i_ths_remove(struct platform_device *pdev)
+{
+ struct ths_device *tmdev = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(tmdev->bus_clk);
+ reset_control_assert(tmdev->reset);
+
+ return 0;
+}
+
+static const struct of_device_id of_ths_match[] = {
+ { .compatible = "allwinner,sun50i-h6-ths"},
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, of_ths_match);
+
+static struct platform_driver ths_driver = {
+ .probe = sun8i_ths_probe,
+ .remove = sun8i_ths_remove,
+ .driver = {
+ .name = "sun8i-thermal",
+ .of_match_table = of_ths_match,
+ },
+};
+module_platform_driver(ths_driver);
+
+MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
+MODULE_LICENSE("GPL v2");
--
2.17.1