[PATCH 2/3] thermal: add Intel BXT WhiskeyCove PMIC thermal driver

[Bin Gao]

This patch adds support for Intel BXT WhiskeyCove pmic thermal driver
which is intended to handle the alert interrupts triggered upon thermal
trip point cross and notify the thermal framework appropriately with
the zone, temp, crossed trip and event details.

Signed-off-by: Yegnesh Iyer <yegnesh.s.iyer@xxxxxxxxx>
Signed-off-by: Bin Gao <bin.gao@xxxxxxxxx>
---
 drivers/thermal/Kconfig              |  10 +++
 drivers/thermal/Makefile             |   1 +
 drivers/thermal/intel_pmic_thermal.c | 159 +++++++++++++++++++++++++++++++++++
 3 files changed, 170 insertions(+)
 create mode 100644 drivers/thermal/intel_pmic_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 2d702ca..9065ba7 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -332,6 +332,16 @@ menu "ACPI INT340X thermal drivers"
 source drivers/thermal/int340x_thermal/Kconfig
 endmenu
 
+config INTEL_PMIC_THERMAL
+	tristate "Intel PMIC thermal driver"
+	depends on X86 && INTEL_SOC_PMIC && REGMAP
+	help
+	  Select this driver for Intel PMIC with ADC channels monitoring system
+	  temperature measurements and alerts.
+	  This driver is used for monitoring the ADC channels of PMIC and handles
+	  the alert trip point interrupts and notifies the thermal framework with
+	  the trip point and temperature details of the zone.
+
 config INTEL_PCH_THERMAL
 	tristate "Intel PCH Thermal Reporting Driver"
 	depends on X86 && PCI
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 10b07c1..159efcc 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -45,6 +45,7 @@ obj-$(CONFIG_INTEL_SOC_DTS_THERMAL)	+= intel_soc_dts_thermal.o
 obj-$(CONFIG_INTEL_QUARK_DTS_THERMAL)	+= intel_quark_dts_thermal.o
 obj-$(CONFIG_TI_SOC_THERMAL)	+= ti-soc-thermal/
 obj-$(CONFIG_INT340X_THERMAL)  += int340x_thermal/
+obj-$(CONFIG_INTEL_PMIC_THERMAL) += intel_pmic_thermal.o
 obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra/
diff --git a/drivers/thermal/intel_pmic_thermal.c b/drivers/thermal/intel_pmic_thermal.c
new file mode 100644
index 0000000..7207b50
--- /dev/null
+++ b/drivers/thermal/intel_pmic_thermal.c
@@ -0,0 +1,159 @@
+/*
+ * pmic_thermal.c - PMIC thermal driver
+ *
+ * Copyright (C) 2012-2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * Author: Iyer, Yegnesh S <yegnesh.s.iyer@xxxxxxxxx>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/thermal.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/mfd/intel_soc_pmic.h>
+
+static irqreturn_t pmic_thermal_irq_handler(int irq, void *data)
+{
+	struct platform_device *pdev = data;
+	struct pmic_thermal_data *td =
+			(struct pmic_thermal_data *)pdev->dev.platform_data;
+	struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
+	struct regmap *regmap = pmic->regmap;
+	struct thermal_zone_device *tzd;
+	int i, j, ret;
+	u16 reg, evt_stat_reg;
+	u8 reg_val, mask, irq_stat, trip;
+
+	/* Resolve thermal irqs */
+	for (i = 0; i < td->num_maps; i++) {
+		for (j = 0; j < td->maps[i].num_trips; j++) {
+			reg = td->maps[i].trip_config[j].irq_reg;
+			mask = td->maps[i].trip_config[j].irq_mask;
+			/*
+			 * Read the irq register to resolve whether the
+			 * interrupt was triggered for this sensor
+			 */
+			if (regmap_read(regmap, reg, &ret))
+				return IRQ_HANDLED;
+
+			reg_val = (u8)ret;
+
+			irq_stat = ((u8)ret & mask);
+			if (irq_stat) {
+				/*
+				 * Read the status register to find out what
+				 * event occurred i.e a high or a low
+				 */
+				evt_stat_reg =
+					td->maps[i].trip_config[j].evt_stat;
+				if (regmap_read(regmap, evt_stat_reg, &ret))
+					return IRQ_HANDLED;
+
+				trip = td->maps[i].trip_config[j].trip_num;
+				tzd = thermal_zone_get_zone_by_name(
+						td->maps[i].handle);
+				if (!IS_ERR(tzd))
+					thermal_zone_device_update(tzd);
+
+				/* Clear the appropriate irq */
+				regmap_write(regmap, reg, reg_val & mask);
+			}
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int pmic_thermal_probe(struct platform_device *pdev)
+{
+	struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
+	struct regmap *regmap = pmic->regmap;
+	struct pmic_thermal_data *thermal_data;
+	struct regmap_irq_chip_data *regmap_irq_chip;
+	int ret, irq, virq, i, j, pmic_irq_count = 0;
+	u16 reg;
+	u8 mask;
+
+	thermal_data = (struct pmic_thermal_data *)pdev->dev.platform_data;
+	if (thermal_data == NULL) {
+		dev_err(&pdev->dev, "No thermal data initialized!!\n");
+		return -ENODEV;
+	}
+
+	regmap_irq_chip = pmic->irq_chip_data_level2;
+	while ((irq = platform_get_irq(pdev, pmic_irq_count)) != -ENXIO) {
+		ret = request_threaded_irq(irq, NULL, pmic_thermal_irq_handler,
+			      IRQF_ONESHOT, "pmic_thermal", thermal_data);
+
+		virq = regmap_irq_get_virq(regmap_irq_chip, irq);
+		if (virq < 0) {
+			dev_err(&pdev->dev,
+				"failed to get virtual interrupt=%d\n", irq);
+			return virq;
+		}
+
+		ret = devm_request_threaded_irq(&pdev->dev, virq,
+				NULL, pmic_thermal_irq_handler,
+				IRQF_ONESHOT, "pmic_thermal", pdev);
+
+		if (ret) {
+			dev_err(&pdev->dev, "request irq failed: %d,virq: %d\n",
+								ret, virq);
+			return ret;
+		}
+		pmic_irq_count++;
+	}
+
+	/* Enable thermal interrupts */
+	for (i = 0; i < thermal_data->num_maps; i++) {
+		for (j = 0; j < thermal_data->maps[i].num_trips; j++) {
+			reg = thermal_data->maps[i].trip_config[j].irq_en;
+			mask = thermal_data->maps[i].trip_config[j].irq_en_mask;
+			if (regmap_update_bits(regmap, reg, mask, 0x00))
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int pmic_thermal_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static struct platform_device_id pmic_thermal_id_table[] = {
+	{ .name = "whiskey_cove_thermal" },
+	{ .name = "bxt_wcove_thermal" },
+	{},
+};
+
+static struct platform_driver pmic_thermal_driver = {
+	.probe = pmic_thermal_probe,
+	.remove = pmic_thermal_remove,
+	.driver = {
+		.name = "pmic_thermal",
+	},
+	.id_table = pmic_thermal_id_table,
+};
+
+MODULE_DEVICE_TABLE(platform, pmic_thermal_id_table);
+module_platform_driver(pmic_thermal_driver);
+
+MODULE_AUTHOR("Iyer, Yegnesh S <yegnesh.s.iyer@xxxxxxxxx>");
+MODULE_DESCRIPTION("PMIC thermal Driver");
+MODULE_LICENSE("GPL");
-- 
1.9.1