thermal: sprd: Add Spreadtrum thermal driver support
authorFreeman Liu <freeman.liu@unisoc.com>
Tue, 18 Feb 2020 08:10:28 +0000 (16:10 +0800)
committerDaniel Lezcano <daniel.lezcano@linaro.org>
Thu, 12 Mar 2020 10:40:57 +0000 (11:40 +0100)
This patch adds the support for Spreadtrum thermal sensor controller,
which can support maximum 8 sensors.

Signed-off-by: Freeman Liu <freeman.liu@unisoc.com>
Co-developed-with: Baolin Wang <baolin.wang@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/ebeb2839cff4d4027b37e787427c5af0e11880c8.1582013101.git.baolin.wang7@gmail.com
drivers/thermal/Kconfig
drivers/thermal/Makefile
drivers/thermal/sprd_thermal.c [new file with mode: 0644]

index 5a05db5438d601be74cecd047c79fdda1d6ce633..a2a940e8a8e3273f61a7220cd21e065c62412092 100644 (file)
@@ -460,4 +460,11 @@ 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
index 9fb88e26fb1020922ad6c46b638f1c03294ae5f9..dbdd98c117f5196e4366566ec3a92da54728a4e3 100644 (file)
@@ -57,3 +57,4 @@ 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 (file)
index 0000000..a340374
--- /dev/null
@@ -0,0 +1,552 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2020 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 *tzd;
+       struct sprd_thermal_data *data;
+       struct device *dev;
+       int cal_slope;
+       int cal_offset;
+       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;
+       int 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);
+
+       if (len > sizeof(u32)) {
+               kfree(buf);
+               return -EINVAL;
+       }
+
+       memcpy(val, buf, len);
+
+       kfree(buf);
+       return 0;
+}
+
+static int sprd_thm_sensor_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;
+
+       ratio += thm->ratio_sign * 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)
+{
+       clamp(rawdata, (u32)SPRD_THM_RAW_DATA_LOW, (u32)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;
+
+       clamp(temp, (int)SPRD_THM_TEMP_LOW, (int)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 clamp(val, val, (u32)(SPRD_THM_RAW_DATA_HIGH - 1));
+}
+
+static int sprd_thm_read_temp(void *devdata, int *temp)
+{
+       struct sprd_thermal_sensor *sen = devdata;
+       u32 data;
+
+       data = readl(sen->data->base + SPRD_THM_TEMP(sen->id)) &
+               SPRD_THM_RAW_READ_MSK;
+
+       *temp = sprd_thm_rawdata_to_temp(sen, data);
+
+       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.
+        *
+        * The SPRD thermal controller integrates a hardware interrupt signal,
+        * which means if the temperature is overheat, it will generate an
+        * interrupt and notify the event to PMIC automatically to shutdown the
+        * system. So here we should enable the interrupt bits, though we have
+        * not registered an irq handler.
+        */
+       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 void sprd_thm_toggle_sensor(struct sprd_thermal_sensor *sen, bool on)
+{
+       struct thermal_zone_device *tzd = sen->tzd;
+
+       tzd->ops->set_mode(tzd,
+               on ? THERMAL_DEVICE_ENABLED : THERMAL_DEVICE_DISABLED);
+}
+
+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;
+       u32 val;
+
+       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", &val);
+       if (ret)
+               goto disable_clk;
+
+       if (val > 0)
+               thm->ratio_sign = -1;
+       else
+               thm->ratio_sign = 1;
+
+       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->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_sensor_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->tzd = devm_thermal_zone_of_sensor_register(sen->dev,
+                                                               sen->id,
+                                                               sen,
+                                                               &sprd_thm_ops);
+               if (IS_ERR(sen->tzd)) {
+                       dev_err(&pdev->dev, "register thermal zone failed %d\n",
+                               sen->id);
+                       ret = PTR_ERR(sen->tzd);
+                       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++)
+               sprd_thm_toggle_sensor(thm->sensor[i], 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++)
+               sprd_thm_toggle_sensor(thm->sensor[i], 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++)
+               sprd_thm_toggle_sensor(thm->sensor[i], 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++) {
+               sprd_thm_toggle_sensor(thm->sensor[i], false);
+               devm_thermal_zone_of_sensor_unregister(&pdev->dev,
+                                                      thm->sensor[i]->tzd);
+       }
+
+       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@unisoc.com>");
+MODULE_DESCRIPTION("Spreadtrum thermal driver");
+MODULE_LICENSE("GPL v2");