[PATCH 4/6] thermal: sti: Add support for ST's Memory Mapped based Thermal controller

Lee Jones
2014-05-30T09:39:17Z

This is the traditional way of obtaining a device driver's register
address space. The aim of this driver is to supply controller specific
information to the ST Thermal Core.

Signed-off-by: Ajit Pal Singh <ajitpal.singh@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/thermal/st/Kconfig | 4 +
drivers/thermal/st/Makefile | 1 +
drivers/thermal/st/st_thermal_memmap.c | 209 +++++++++++++++++++++++++++++++++
3 files changed, 214 insertions(+)
create mode 100644 drivers/thermal/st/st_thermal_memmap.c

diff --git a/drivers/thermal/st/Kconfig b/drivers/thermal/st/Kconfig
index d7b6e03..490fdbe 100644
--- a/drivers/thermal/st/Kconfig
+++ b/drivers/thermal/st/Kconfig
@@ -6,3 +6,7 @@ config ST_THERMAL
config ST_THERMAL_SYSCFG
select ST_THERMAL
tristate "STi series syscfg register access based thermal sensors"
+
+config ST_THERMAL_MEMMAP
+ select ST_THERMAL
+ tristate "STi series memory mapped access based thermal sensors"
diff --git a/drivers/thermal/st/Makefile b/drivers/thermal/st/Makefile
index e5058c6..b388789 100644
--- a/drivers/thermal/st/Makefile
+++ b/drivers/thermal/st/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_ST_THERMAL) := st_thermal.o
obj-$(CONFIG_ST_THERMAL_SYSCFG) += st_thermal_syscfg.o
+obj-$(CONFIG_ST_THERMAL_MEMMAP) += st_thermal_memmap.o
diff --git a/drivers/thermal/st/st_thermal_memmap.c b/drivers/thermal/st/st_thermal_memmap.c
new file mode 100644
index 0000000..39896ce
--- /dev/null
+++ b/drivers/thermal/st/st_thermal_memmap.c
@@ -0,0 +1,209 @@
+/*
+ * ST Thermal Sensor Driver for memory mapped sensors.
+ * Author: Ajit Pal Singh <ajitpal.singh@st.com>
+ *
+ * Copyright (C) 2003-2014 STMicroelectronics (R&D) Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/of.h>
+#include <linux/module.h>
+
+#include "st_thermal.h"
+
+#define STIH416_MPE_CONF 0x0
+#define STIH416_MPE_STATUS 0x4
+#define STIH416_MPE_INT_THRESH 0x8
+#define STIH416_MPE_INT_EN 0xC
+
+/* Power control bits for the memory mapped thermal sensor */
+#define THERMAL_PDN BIT(4)
+#define THERMAL_SRSTN BIT(10)
+
+static const struct reg_field st_mmap_thermal_regfields[MAX_REGFIELDS] = {
+ /*
+ * According to the STIH416 MPE temp sensor data sheet -
+ * the PDN (Power Down Bit) and SRSTN (Soft Reset Bit) need to be
+ * written simultaneously for powering on and off the temperature
+ * sensor. regmap_update_bits() will be used to update the register.
+ */
+ [INT_THRESH_HI] = REG_FIELD(STIH416_MPE_INT_THRESH, 0, 7),
+ [DCORRECT] = REG_FIELD(STIH416_MPE_CONF, 5, 9),
+ [OVERFLOW] = REG_FIELD(STIH416_MPE_STATUS, 9, 9),
+ [DATA] = REG_FIELD(STIH416_MPE_STATUS, 11, 18),
+ [INT_ENABLE] = REG_FIELD(STIH416_MPE_INT_EN, 0, 0),
+};
+
+static irqreturn_t st_mmap_thermal_trip_handler(int irq, void *sdata)
+{
+ struct st_thermal_sensor *sensor = sdata;
+
+ thermal_zone_device_update(sensor->thermal_dev);
+
+ return IRQ_HANDLED;
+}
+
+/* Private ops for the Memory Mapped based thermal sensors */
+static int st_mmap_power_ctrl(struct st_thermal_sensor *sensor,
+ enum st_thermal_power_state power_state)
+{
+ const unsigned int mask = (THERMAL_PDN | THERMAL_SRSTN);
+ const unsigned int val = power_state ? mask : 0;
+
+ return regmap_update_bits(sensor->regmap, STIH416_MPE_CONF, mask, val);
+}
+
+static int st_mmap_alloc_regfields(struct st_thermal_sensor *sensor)
+{
+ struct device *dev = sensor->dev;
+ struct regmap *regmap = sensor->regmap;
+ const struct reg_field *reg_fields = sensor->cdata->reg_fields;
+
+ sensor->int_thresh_hi = devm_regmap_field_alloc(dev, regmap,
+ reg_fields[INT_THRESH_HI]);
+ sensor->int_enable = devm_regmap_field_alloc(dev, regmap,
+ reg_fields[INT_ENABLE]);
+
+ if (IS_ERR(sensor->int_thresh_hi) || IS_ERR(sensor->int_enable)) {
+ dev_err(dev, "failed to alloc mmap regfields\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int st_mmap_enable_irq(struct st_thermal_sensor *sensor)
+{
+ int ret;
+
+ /* Set upper critical threshold */
+ ret = regmap_field_write(sensor->int_thresh_hi,
+ sensor->cdata->crit_temp -
+ sensor->cdata->temp_adjust_val);
+ if (ret)
+ return ret;
+
+ return regmap_field_write(sensor->int_enable, 1);
+}
+
+static int st_mmap_register_enable_irq(struct st_thermal_sensor *sensor)
+{
+ struct device *dev = sensor->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ int ret;
+
+ sensor->irq = platform_get_irq(pdev, 0);
+ if (sensor->irq < 0) {
+ dev_err(dev, "failed to register IRQ\n");
+ return sensor->irq;
+ }
+
+ ret = devm_request_threaded_irq(dev, sensor->irq,
+ NULL, st_mmap_thermal_trip_handler,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ dev->driver->name, sensor);
+ if (ret) {
+ dev_err(dev, "failed to register IRQ %d\n", sensor->irq);
+ return ret;
+ }
+
+ return st_mmap_enable_irq(sensor);
+}
+
+static const struct regmap_config st_416mpe_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
+static int st_mmap_regmap_init(struct st_thermal_sensor *sensor)
+{
+ struct device *dev = sensor->dev;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(dev, "no memory resources defined\n");
+ return -ENODEV;
+ }
+
+ sensor->mmio_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(sensor->mmio_base)) {
+ dev_err(dev, "failed to remap IO\n");
+ return PTR_ERR(sensor->mmio_base);
+ }
+
+ sensor->regmap = devm_regmap_init_mmio(dev, sensor->mmio_base,
+ &st_416mpe_regmap_config);
+ if (IS_ERR(sensor->regmap)) {
+ dev_err(dev, "failed to initialise regmap\n");
+ return PTR_ERR(sensor->regmap);
+ }
+
+ return 0;
+}
+
+static const struct st_thermal_sensor_ops st_mmap_sensor_ops = {
+ .power_ctrl = st_mmap_power_ctrl,
+ .alloc_regfields = st_mmap_alloc_regfields,
+ .regmap_init = st_mmap_regmap_init,
+ .register_enable_irq = st_mmap_register_enable_irq,
+ .enable_irq = st_mmap_enable_irq,
+};
+
+/* Compatible device data stih416 mpe thermal sensor */
+const struct st_thermal_compat_data st_416mpe_cdata = {
+ .reg_fields = st_mmap_thermal_regfields,
+ .ops = &st_mmap_sensor_ops,
+ .calibration_val = 14,
+ .temp_adjust_val = -95,
+ .crit_temp = 120,
+};
+
+/* Compatible device data stih407 thermal sensor */
+const struct st_thermal_compat_data st_407_cdata = {
+ .reg_fields = st_mmap_thermal_regfields,
+ .ops = &st_mmap_sensor_ops,
+ .calibration_val = 16,
+ .temp_adjust_val = -95,
+ .crit_temp = 120,
+};
+
+static struct of_device_id st_mmap_thermal_of_match[] = {
+ { .compatible = "st,stih416-mpe-thermal", .data = &st_416mpe_cdata },
+ { .compatible = "st,stih407-thermal", .data = &st_407_cdata },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, st_mmap_thermal_of_match);
+
+int st_mmap_probe(struct platform_device *pdev)
+{
+ return st_thermal_register(pdev, st_mmap_thermal_of_match);
+}
+
+int st_mmap_remove(struct platform_device *pdev)
+{
+ return st_thermal_unregister(pdev);
+}
+
+static struct platform_driver st_mmap_thermal_driver = {
+ .driver = {
+ .name = "st_thermal_mmap",
+ .owner = THIS_MODULE,
+ .pm = &st_thermal_pm_ops,
+ .of_match_table = st_mmap_thermal_of_match,
+ },
+ .probe = st_mmap_probe,
+ .remove = st_mmap_remove,
+};
+
+module_platform_driver(st_mmap_thermal_driver);
+
+MODULE_AUTHOR("STMicroelectronics (R&D) Limited <ajitpal.singh@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STi SoC Thermal Sensor Driver");
+MODULE_LICENSE("GPL v2");
--
1.8.3.2