[PATCH v2 2/2] thermal: sprd: Add Spreadtrum thermal driver support

From: Baolin Wang
Date: Tue Dec 10 2019 - 07:08:23 EST


From: Freeman Liu <freeman.liu@xxxxxxxxxx>

This patch adds the support for Spreadtrum thermal sensor controller,
which can support maximum 8 sensors.

Signed-off-by: Freeman Liu <freeman.liu@xxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang7@xxxxxxxxx>
---
Changes from v1:
- None.
---
drivers/thermal/Kconfig | 7 +
drivers/thermal/Makefile | 1 +
drivers/thermal/sprd_thermal.c | 548 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 556 insertions(+)
create mode 100644 drivers/thermal/sprd_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 59b79fc..646873d 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -429,4 +429,11 @@ config UNIPHIER_THERMAL
Enable this to plug in UniPhier on-chip PVT thermal driver into the
thermal framework. The driver supports CPU thermal zone temperature
reporting and a couple of trip points.
+
+config SPRD_THERMAL
+ tristate "Temperature sensor on Spreadtrum SoCs"
+ depends on ARCH_SPRD || COMPILE_TEST
+ help
+ Support for the Spreadtrum thermal sensor driver in the Linux thermal
+ framework.
endif
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index baeb70b..544d867 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -55,3 +55,4 @@ obj-$(CONFIG_GENERIC_ADC_THERMAL) += thermal-generic-adc.o
obj-$(CONFIG_ZX2967_THERMAL) += zx2967_thermal.o
obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o
obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o
+obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o
diff --git a/drivers/thermal/sprd_thermal.c b/drivers/thermal/sprd_thermal.c
new file mode 100644
index 0000000..d9b6074
--- /dev/null
+++ b/drivers/thermal/sprd_thermal.c
@@ -0,0 +1,548 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2019 Spreadtrum Communications Inc.
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define SPRD_THM_CTL 0x0
+#define SPRD_THM_INT_EN 0x4
+#define SPRD_THM_INT_STS 0x8
+#define SPRD_THM_INT_RAW_STS 0xc
+#define SPRD_THM_DET_PERIOD 0x10
+#define SPRD_THM_INT_CLR 0x14
+#define SPRD_THM_INT_CLR_ST 0x18
+#define SPRD_THM_MON_PERIOD 0x4c
+#define SPRD_THM_MON_CTL 0x50
+#define SPRD_THM_INTERNAL_STS1 0x54
+#define SPRD_THM_RAW_READ_MSK 0x3ff
+
+#define SPRD_THM_OFFSET(id) ((id) * 0x4)
+#define SPRD_THM_TEMP(id) (SPRD_THM_OFFSET(id) + 0x5c)
+#define SPRD_THM_THRES(id) (SPRD_THM_OFFSET(id) + 0x2c)
+
+#define SPRD_THM_SEN(id) BIT((id) + 2)
+#define SPRD_THM_SEN_OVERHEAT_EN(id) BIT((id) + 8)
+#define SPRD_THM_SEN_OVERHEAT_ALARM_EN(id) BIT((id) + 0)
+
+/* bits definitions for register THM_CTL */
+#define SPRD_THM_SET_RDY_ST BIT(13)
+#define SPRD_THM_SET_RDY BIT(12)
+#define SPRD_THM_MON_EN BIT(1)
+#define SPRD_THM_EN BIT(0)
+
+/* bits definitions for register THM_INT_CTL */
+#define SPRD_THM_BIT_INT_EN BIT(26)
+#define SPRD_THM_OVERHEAT_EN BIT(25)
+#define SPRD_THM_OTP_TRIP_SHIFT 10
+
+/* bits definitions for register SPRD_THM_INTERNAL_STS1 */
+#define SPRD_THM_TEMPER_RDY BIT(0)
+
+#define SPRD_THM_DET_PERIOD_DATA 0x800
+#define SPRD_THM_DET_PERIOD_MASK GENMASK(19, 0)
+#define SPRD_THM_MON_MODE 0x7
+#define SPRD_THM_MON_MODE_MASK GENMASK(3, 0)
+#define SPRD_THM_MON_PERIOD_DATA 0x10
+#define SPRD_THM_MON_PERIOD_MASK GENMASK(15, 0)
+#define SPRD_THM_THRES_MASK GENMASK(19, 0)
+#define SPRD_THM_INT_CLR_MASK GENMASK(24, 0)
+
+/* thermal sensor calibration parameters */
+#define SPRD_THM_TEMP_LOW -40000
+#define SPRD_THM_TEMP_HIGH 120000
+#define SPRD_THM_OTP_TEMP 120000
+#define SPRD_THM_HOT_TEMP 75000
+#define SPRD_THM_RAW_DATA_LOW 0
+#define SPRD_THM_RAW_DATA_HIGH 1000
+#define SPRD_THM_SEN_NUM 8
+#define SPRD_THM_DT_OFFSET 24
+#define SPRD_THM_RATION_OFFSET 17
+#define SPRD_THM_RATION_SIGN 16
+
+#define SPRD_THM_RDYST_POLLING_TIME 10
+#define SPRD_THM_RDYST_TIMEOUT 700
+#define SPRD_THM_TEMP_READY_POLL_TIME 10000
+#define SPRD_THM_TEMP_READY_TIMEOUT 600000
+#define SPRD_THM_MAX_SENSOR 8
+
+struct sprd_thermal_sensor {
+ struct thermal_zone_device *thmzone_dev;
+ struct sprd_thermal_data *data;
+ struct device *dev;
+ bool ready;
+ int cal_slope;
+ int cal_offset;
+ int last_temp;
+ int id;
+};
+
+struct sprd_thermal_data {
+ const struct sprd_thm_variant_data *var_data;
+ struct sprd_thermal_sensor *sensor[SPRD_THM_MAX_SENSOR];
+ struct clk *clk;
+ void __iomem *base;
+ u32 ratio_off;
+ u32 ratio_sign;
+ int nr_sensors;
+};
+
+/*
+ * The conversion between ADC and temperature is based on linear relationship,
+ * and use idea_k to specify the slope and ideal_b to specify the offset.
+ *
+ * Since different Spreadtrum SoCs have different ideal_k and ideal_b,
+ * we should save ideal_k and ideal_b in the device data structure.
+ */
+struct sprd_thm_variant_data {
+ u32 ideal_k;
+ u32 ideal_b;
+};
+
+static const struct sprd_thm_variant_data ums512_data = {
+ .ideal_k = 262,
+ .ideal_b = 66400,
+};
+
+static inline void sprd_thm_update_bits(void __iomem *reg, u32 mask, u32 val)
+{
+ u32 tmp, orig;
+
+ orig = readl(reg);
+ tmp = orig & ~mask;
+ tmp |= val & mask;
+ writel(tmp, reg);
+}
+
+static int sprd_thm_cal_read(struct device_node *np, const char *cell_id,
+ u32 *val)
+{
+ struct nvmem_cell *cell;
+ void *buf;
+ size_t len;
+
+ cell = of_nvmem_cell_get(np, cell_id);
+ if (IS_ERR(cell))
+ return PTR_ERR(cell);
+
+ buf = nvmem_cell_read(cell, &len);
+ nvmem_cell_put(cell);
+ if (IS_ERR(buf))
+ return PTR_ERR(buf);
+
+ memcpy(val, buf, min(len, sizeof(u32)));
+
+ kfree(buf);
+ return 0;
+}
+
+static int sprd_thm_senor_calibration(struct device_node *np,
+ struct sprd_thermal_data *thm,
+ struct sprd_thermal_sensor *sen)
+{
+ int ret;
+ /*
+ * According to thermal datasheet, the default calibration offset is 64,
+ * and the default ratio is 1000.
+ */
+ int dt_offset = 64, ratio = 1000;
+
+ ret = sprd_thm_cal_read(np, "sen_delta_cal", &dt_offset);
+ if (ret)
+ return ret;
+
+ if (thm->ratio_sign == 1)
+ ratio = 1000 - thm->ratio_off;
+ else
+ ratio = 1000 + thm->ratio_off;
+
+ /*
+ * According to the ideal slope K and ideal offset B, combined with
+ * calibration value of thermal from efuse, then calibrate the real
+ * slope k and offset b:
+ * k_cal = (k * ratio) / 1000.
+ * b_cal = b + (dt_offset - 64) * 500.
+ */
+ sen->cal_slope = (thm->var_data->ideal_k * ratio) / 1000;
+ sen->cal_offset = thm->var_data->ideal_b + (dt_offset - 128) * 250;
+
+ return 0;
+}
+
+static int sprd_thm_rawdata_to_temp(struct sprd_thermal_sensor *sen,
+ u32 rawdata)
+{
+ if (rawdata < SPRD_THM_RAW_DATA_LOW)
+ rawdata = SPRD_THM_RAW_DATA_LOW;
+ else if (rawdata > SPRD_THM_RAW_DATA_HIGH)
+ rawdata = SPRD_THM_RAW_DATA_HIGH;
+
+ /*
+ * According to the thermal datasheet, the formula of converting
+ * adc value to the temperature value should be:
+ * T_final = k_cal * x - b_cal.
+ */
+ return sen->cal_slope * rawdata - sen->cal_offset;
+}
+
+static int sprd_thm_temp_to_rawdata(int temp, struct sprd_thermal_sensor *sen)
+{
+ u32 val;
+
+ if (temp < SPRD_THM_TEMP_LOW)
+ temp = SPRD_THM_TEMP_LOW;
+ else if (temp > SPRD_THM_TEMP_HIGH)
+ temp = SPRD_THM_TEMP_HIGH;
+
+ /*
+ * According to the thermal datasheet, the formula of converting
+ * adc value to the temperature value should be:
+ * T_final = k_cal * x - b_cal.
+ */
+ val = (temp + sen->cal_offset) / sen->cal_slope;
+
+ return val >= SPRD_THM_RAW_DATA_HIGH ? (SPRD_THM_RAW_DATA_HIGH - 1) : val;
+}
+
+static int sprd_thm_read_temp(void *devdata, int *temp)
+{
+ struct sprd_thermal_sensor *sen = devdata;
+ int sensor_temp;
+ u32 data;
+
+ data = readl(sen->data->base + SPRD_THM_TEMP(sen->id)) &
+ SPRD_THM_RAW_READ_MSK;
+
+ if (sen->ready) {
+ sensor_temp = sprd_thm_rawdata_to_temp(sen, data);
+ sen->last_temp = sensor_temp;
+ *temp = sensor_temp;
+ } else {
+ /*
+ * If the sensor is not ready, then just return last
+ * temperature value.
+ */
+ *temp = sen->last_temp;
+ }
+
+ return 0;
+}
+
+static const struct thermal_zone_of_device_ops sprd_thm_ops = {
+ .get_temp = sprd_thm_read_temp,
+};
+
+static int sprd_thm_poll_ready_status(struct sprd_thermal_data *thm)
+{
+ u32 val;
+ int ret;
+
+ /*
+ * Wait for thermal ready status before configuring thermal parameters.
+ */
+ ret = readl_poll_timeout(thm->base + SPRD_THM_CTL, val,
+ !(val & SPRD_THM_SET_RDY_ST),
+ SPRD_THM_RDYST_POLLING_TIME,
+ SPRD_THM_RDYST_TIMEOUT);
+ if (ret)
+ return ret;
+
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_MON_EN,
+ SPRD_THM_MON_EN);
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SET_RDY,
+ SPRD_THM_SET_RDY);
+ return 0;
+}
+
+static int sprd_thm_wait_temp_ready(struct sprd_thermal_data *thm)
+{
+ u32 val;
+
+ /* Wait for first temperature data ready before reading temperature */
+ return readl_poll_timeout(thm->base + SPRD_THM_INTERNAL_STS1, val,
+ !(val & SPRD_THM_TEMPER_RDY),
+ SPRD_THM_TEMP_READY_POLL_TIME,
+ SPRD_THM_TEMP_READY_TIMEOUT);
+}
+
+static int sprd_thm_set_ready(struct sprd_thermal_data *thm)
+{
+ int ret;
+
+ ret = sprd_thm_poll_ready_status(thm);
+ if (ret)
+ return ret;
+
+ /*
+ * Clear interrupt status, enable thermal interrupt and enable thermal.
+ */
+ writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
+ sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
+ SPRD_THM_BIT_INT_EN, SPRD_THM_BIT_INT_EN);
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+ SPRD_THM_EN, SPRD_THM_EN);
+ return 0;
+}
+
+static void sprd_thm_sensor_init(struct sprd_thermal_data *thm,
+ struct sprd_thermal_sensor *sen)
+{
+ u32 otp_rawdata, hot_rawdata;
+
+ otp_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_OTP_TEMP, sen);
+ hot_rawdata = sprd_thm_temp_to_rawdata(SPRD_THM_HOT_TEMP, sen);
+
+ /* Enable the sensor' overheat temperature protection interrupt */
+ sprd_thm_update_bits(thm->base + SPRD_THM_INT_EN,
+ SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id),
+ SPRD_THM_SEN_OVERHEAT_ALARM_EN(sen->id));
+
+ /* Set the sensor' overheat and hot threshold temperature */
+ sprd_thm_update_bits(thm->base + SPRD_THM_THRES(sen->id),
+ SPRD_THM_THRES_MASK,
+ (otp_rawdata << SPRD_THM_OTP_TRIP_SHIFT) |
+ hot_rawdata);
+
+ /* Enable the corresponding sensor */
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL, SPRD_THM_SEN(sen->id),
+ SPRD_THM_SEN(sen->id));
+}
+
+static void sprd_thm_para_config(struct sprd_thermal_data *thm)
+{
+ /* Set the period of two valid temperature detection action */
+ sprd_thm_update_bits(thm->base + SPRD_THM_DET_PERIOD,
+ SPRD_THM_DET_PERIOD_MASK, SPRD_THM_DET_PERIOD);
+
+ /* Set the sensors' monitor mode */
+ sprd_thm_update_bits(thm->base + SPRD_THM_MON_CTL,
+ SPRD_THM_MON_MODE_MASK, SPRD_THM_MON_MODE);
+
+ /* Set the sensors' monitor period */
+ sprd_thm_update_bits(thm->base + SPRD_THM_MON_PERIOD,
+ SPRD_THM_MON_PERIOD_MASK, SPRD_THM_MON_PERIOD);
+}
+
+static int sprd_thm_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct device_node *sen_child;
+ struct sprd_thermal_data *thm;
+ struct sprd_thermal_sensor *sen;
+ const struct sprd_thm_variant_data *pdata;
+ int ret, i;
+
+ pdata = of_device_get_match_data(&pdev->dev);
+ if (!pdata) {
+ dev_err(&pdev->dev, "No matching driver data found\n");
+ return -EINVAL;
+ }
+
+ thm = devm_kzalloc(&pdev->dev, sizeof(*thm), GFP_KERNEL);
+ if (!thm)
+ return -ENOMEM;
+
+ thm->var_data = pdata;
+ thm->base = devm_platform_ioremap_resource(pdev, 0);
+ if (!thm->base)
+ return -ENOMEM;
+
+ thm->nr_sensors = of_get_child_count(np);
+ if (thm->nr_sensors == 0 || thm->nr_sensors > SPRD_THM_MAX_SENSOR) {
+ dev_err(&pdev->dev, "incorrect sensor count\n");
+ return -EINVAL;
+ }
+
+ thm->clk = devm_clk_get(&pdev->dev, "enable");
+ if (IS_ERR(thm->clk)) {
+ dev_err(&pdev->dev, "failed to get enable clock\n");
+ return PTR_ERR(thm->clk);
+ }
+
+ ret = clk_prepare_enable(thm->clk);
+ if (ret)
+ return ret;
+
+ sprd_thm_para_config(thm);
+
+ ret = sprd_thm_cal_read(np, "thm_sign_cal", &thm->ratio_sign);
+ if (ret)
+ goto disable_clk;
+
+ ret = sprd_thm_cal_read(np, "thm_ratio_cal", &thm->ratio_off);
+ if (ret)
+ goto disable_clk;
+
+ for_each_child_of_node(np, sen_child) {
+ sen = devm_kzalloc(&pdev->dev, sizeof(*sen), GFP_KERNEL);
+ if (!sen) {
+ ret = -ENOMEM;
+ goto disable_clk;
+ }
+
+ sen->ready = false;
+ sen->data = thm;
+ sen->dev = &pdev->dev;
+
+ ret = of_property_read_u32(sen_child, "reg", &sen->id);
+ if (ret) {
+ dev_err(&pdev->dev, "get sensor reg failed");
+ goto disable_clk;
+ }
+
+ ret = sprd_thm_senor_calibration(sen_child, thm, sen);
+ if (ret) {
+ dev_err(&pdev->dev, "efuse cal analysis failed");
+ goto disable_clk;
+ }
+
+ sprd_thm_sensor_init(thm, sen);
+
+ sen->thmzone_dev =
+ devm_thermal_zone_of_sensor_register(sen->dev, sen->id,
+ sen, &sprd_thm_ops);
+ if (IS_ERR(sen->thmzone_dev)) {
+ dev_err(&pdev->dev, "register thermal zone failed %d\n",
+ sen->id);
+ ret = PTR_ERR(sen->thmzone_dev);
+ goto disable_clk;
+ }
+
+ thm->sensor[sen->id] = sen;
+ }
+
+ ret = sprd_thm_set_ready(thm);
+ if (ret)
+ goto disable_clk;
+
+ ret = sprd_thm_wait_temp_ready(thm);
+ if (ret)
+ goto disable_clk;
+
+ for (i = 0; i < thm->nr_sensors; i++)
+ thm->sensor[i]->ready = true;
+
+ platform_set_drvdata(pdev, thm);
+ return 0;
+
+disable_clk:
+ clk_disable_unprepare(thm->clk);
+ return ret;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static void sprd_thm_hw_suspend(struct sprd_thermal_data *thm)
+{
+ int i;
+
+ for (i = 0; i < thm->nr_sensors; i++) {
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+ SPRD_THM_SEN(thm->sensor[i]->id), 0);
+ }
+
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+ SPRD_THM_EN, 0x0);
+}
+
+static int sprd_thm_suspend(struct device *dev)
+{
+ struct sprd_thermal_data *thm = dev_get_drvdata(dev);
+ int i;
+
+ for (i = 0; i < thm->nr_sensors; i++)
+ thm->sensor[i]->ready = false;
+
+ sprd_thm_hw_suspend(thm);
+ clk_disable_unprepare(thm->clk);
+
+ return 0;
+}
+
+static int sprd_thm_hw_resume(struct sprd_thermal_data *thm)
+{
+ int ret, i;
+
+ for (i = 0; i < thm->nr_sensors; i++) {
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+ SPRD_THM_SEN(thm->sensor[i]->id),
+ SPRD_THM_SEN(thm->sensor[i]->id));
+ }
+
+ ret = sprd_thm_poll_ready_status(thm);
+ if (ret)
+ return ret;
+
+ writel(SPRD_THM_INT_CLR_MASK, thm->base + SPRD_THM_INT_CLR);
+ sprd_thm_update_bits(thm->base + SPRD_THM_CTL,
+ SPRD_THM_EN, SPRD_THM_EN);
+ return sprd_thm_wait_temp_ready(thm);
+}
+
+static int sprd_thm_resume(struct device *dev)
+{
+ struct sprd_thermal_data *thm = dev_get_drvdata(dev);
+ int ret, i;
+
+ ret = clk_prepare_enable(thm->clk);
+ if (ret)
+ return ret;
+
+ ret = sprd_thm_hw_resume(thm);
+ if (ret)
+ goto disable_clk;
+
+ for (i = 0; i < thm->nr_sensors; i++)
+ thm->sensor[i]->ready = true;
+
+ return 0;
+
+disable_clk:
+ clk_disable_unprepare(thm->clk);
+ return ret;
+}
+#endif
+
+static int sprd_thm_remove(struct platform_device *pdev)
+{
+ struct sprd_thermal_data *thm = platform_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < thm->nr_sensors; i++) {
+ devm_thermal_zone_of_sensor_unregister(&pdev->dev,
+ thm->sensor[i]->thmzone_dev);
+ }
+
+ clk_disable_unprepare(thm->clk);
+ return 0;
+}
+
+static const struct of_device_id sprd_thermal_of_match[] = {
+ { .compatible = "sprd,ums512-thermal", .data = &ums512_data },
+ { },
+};
+
+static const struct dev_pm_ops sprd_thermal_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(sprd_thm_suspend, sprd_thm_resume)
+};
+
+static struct platform_driver sprd_thermal_driver = {
+ .probe = sprd_thm_probe,
+ .remove = sprd_thm_remove,
+ .driver = {
+ .name = "sprd-thermal",
+ .pm = &sprd_thermal_pm_ops,
+ .of_match_table = sprd_thermal_of_match,
+ },
+};
+
+module_platform_driver(sprd_thermal_driver);
+
+MODULE_AUTHOR("Freeman Liu <freeman.liu@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Spreadtrum thermal driver");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5