[PATCH v5] thermal: add Intel BXT WhiskeyCove PMIC thermal driver

[Bin Gao]

This change adds support for Intel BXT Whiskey Cove 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 S Iyer <yegnesh.s.iyer@xxxxxxxxx>
Signed-off-by: Bin Gao <bin.gao@xxxxxxxxx>
---
Changes in v5:
 - Applied patch Joe Perches <joe@xxxxxxxxxxx> and reduced data
   segment size
 - Applied patch from Julia Lawall <julia.lawall@xxxxxxx> and fixed
   the platform_device_id to NULL entry terminated error
Changes in v4:
 - Fixed copyright year and changed GPL to GPL v2
Changes in v3:
 - Moved driver data from mfd domain to the driver
 - Minor coding style related cleanup
Changes in v2:
 - Removed unnecessary request_threaded_irq() - we should be only
   using devm_request_threaded_irq() with virq
 drivers/thermal/Kconfig                  |  10 ++
 drivers/thermal/Makefile                 |   1 +
 drivers/thermal/intel_bxt_pmic_thermal.c | 299 +++++++++++++++++++++++++++++++
 3 files changed, 310 insertions(+)
 create mode 100644 drivers/thermal/intel_bxt_pmic_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 2d702ca..9bdd624 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_BXT_PMIC_THERMAL
+	tristate "Intel Broxton PMIC thermal driver"
+	depends on X86 && INTEL_SOC_PMIC && REGMAP
+	help
+	  Select this driver for Intel Broxton 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..7aa7f4c 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-$(CONFIG_INTEL_BXT_PMIC_THERMAL) += intel_bxt_pmic_thermal.o
 obj-$(CONFIG_INTEL_PCH_THERMAL)	+= intel_pch_thermal.o
 obj-$(CONFIG_ST_THERMAL)	+= st/
 obj-$(CONFIG_TEGRA_SOCTHERM)	+= tegra/
diff --git a/drivers/thermal/intel_bxt_pmic_thermal.c b/drivers/thermal/intel_bxt_pmic_thermal.c
new file mode 100644
index 0000000..4ae3e0c
--- /dev/null
+++ b/drivers/thermal/intel_bxt_pmic_thermal.c
@@ -0,0 +1,299 @@
+/*
+ * Intel Broxton PMIC thermal driver
+ *
+ * Copyright (C) 2016 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.
+ *
+ */
+
+#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>
+
+#define BXTWC_THRM0IRQ		0x4E04
+#define BXTWC_THRM1IRQ		0x4E05
+#define BXTWC_THRM2IRQ		0x4E06
+#define BXTWC_MTHRM0IRQ		0x4E12
+#define BXTWC_MTHRM1IRQ		0x4E13
+#define BXTWC_MTHRM2IRQ		0x4E14
+#define BXTWC_STHRM0IRQ		0x4F19
+#define BXTWC_STHRM1IRQ		0x4F1A
+#define BXTWC_STHRM2IRQ		0x4F1B
+
+struct trip_config_map {
+	u16 irq_reg;
+	u16 irq_en;
+	u16 evt_stat;
+	u8 irq_mask;
+	u8 irq_en_mask;
+	u8 evt_mask;
+	u8 trip_num;
+};
+
+struct thermal_irq_map {
+	char handle[20];
+	int num_trips;
+	const struct trip_config_map *trip_config;
+};
+
+struct pmic_thermal_data {
+	const struct thermal_irq_map *maps;
+	int num_maps;
+};
+
+static const struct trip_config_map bxtwc_str0_trip_config[] = {
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x01,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x01,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x01,
+		.trip_num = 0
+	},
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x10,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x10,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x10,
+		.trip_num = 1
+	}
+};
+
+static const struct trip_config_map bxtwc_str1_trip_config[] = {
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x02,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x02,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x02,
+		.trip_num = 0
+	},
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x20,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x20,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x20,
+		.trip_num = 1
+	},
+};
+
+static const struct trip_config_map bxtwc_str2_trip_config[] = {
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x04,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x04,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x04,
+		.trip_num = 0
+	},
+	{
+		.irq_reg = BXTWC_THRM0IRQ,
+		.irq_mask = 0x40,
+		.irq_en = BXTWC_MTHRM0IRQ,
+		.irq_en_mask = 0x40,
+		.evt_stat = BXTWC_STHRM0IRQ,
+		.evt_mask = 0x40,
+		.trip_num = 1
+	},
+};
+
+static const struct trip_config_map bxtwc_str3_trip_config[] = {
+	{
+		.irq_reg = BXTWC_THRM2IRQ,
+		.irq_mask = 0x10,
+		.irq_en = BXTWC_MTHRM2IRQ,
+		.irq_en_mask = 0x10,
+		.evt_stat = BXTWC_STHRM2IRQ,
+		.evt_mask = 0x10,
+		.trip_num = 0
+	},
+};
+
+static const struct thermal_irq_map bxtwc_thermal_irq_map[] = {
+	{
+		.handle = "STR0",
+		.trip_config = bxtwc_str0_trip_config,
+		.num_trips = ARRAY_SIZE(bxtwc_str0_trip_config),
+	},
+	{
+		.handle = "STR1",
+		.trip_config = bxtwc_str1_trip_config,
+		.num_trips = ARRAY_SIZE(bxtwc_str1_trip_config),
+	},
+	{
+		.handle = "STR2",
+		.trip_config = bxtwc_str2_trip_config,
+		.num_trips = ARRAY_SIZE(bxtwc_str2_trip_config),
+	},
+	{
+		.handle = "STR3",
+		.trip_config = bxtwc_str3_trip_config,
+		.num_trips = ARRAY_SIZE(bxtwc_str3_trip_config),
+	},
+};
+
+static const struct pmic_thermal_data bxtwc_thermal_data = {
+	.maps = bxtwc_thermal_irq_map,
+	.num_maps = ARRAY_SIZE(bxtwc_thermal_irq_map),
+};
+
+static irqreturn_t pmic_thermal_irq_handler(int irq, void *data)
+{
+	struct platform_device *pdev = data;
+	struct thermal_zone_device *tzd;
+	struct pmic_thermal_data *td;
+	struct intel_soc_pmic *pmic;
+	struct regmap *regmap;
+	u8 reg_val, mask, irq_stat, trip;
+	u16 reg, evt_stat_reg;
+	int i, j, ret;
+
+	pmic = dev_get_drvdata(pdev->dev.parent);
+	regmap = pmic->regmap;
+	td = (struct pmic_thermal_data *)
+		platform_get_device_id(pdev)->driver_data;
+
+	/* 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)
+				continue;
+
+			/*
+			 * 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 regmap_irq_chip_data *regmap_irq_chip;
+	struct pmic_thermal_data *thermal_data;
+	int ret, irq, virq, i, j, pmic_irq_count;
+	struct intel_soc_pmic *pmic;
+	struct regmap *regmap;
+	struct device *dev;
+	u16 reg;
+	u8 mask;
+
+	dev = &pdev->dev;
+	pmic = dev_get_drvdata(pdev->dev.parent);
+	if (!pmic) {
+		dev_err(dev, "Failed to get struct intel_soc_pmic pointer\n");
+		return -ENODEV;
+	}
+
+	thermal_data = (struct pmic_thermal_data *)
+				platform_get_device_id(pdev)->driver_data;
+	if (!thermal_data) {
+		dev_err(dev, "No thermal data initialized!!\n");
+		return -ENODEV;
+	}
+
+	regmap = pmic->regmap;
+	regmap_irq_chip = pmic->irq_chip_data_level2;
+
+	pmic_irq_count = 0;
+	while ((irq = platform_get_irq(pdev, pmic_irq_count)) != -ENXIO) {
+		virq = regmap_irq_get_virq(regmap_irq_chip, irq);
+		if (virq < 0) {
+			dev_err(dev, "failed to get virq by irq %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(dev, "request irq(%d) failed: %d\n", virq, ret);
+			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;
+			ret = regmap_update_bits(regmap, reg, mask, 0x00);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct platform_device_id pmic_thermal_id_table[] = {
+	{
+		.name = "bxt_wcove_thermal",
+		.driver_data = (kernel_ulong_t)&bxtwc_thermal_data,
+	},
+	{},
+};
+
+static struct platform_driver pmic_thermal_driver = {
+	.probe = pmic_thermal_probe,
+	.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("Yegnesh S Iyer <yegnesh.s.iyer@xxxxxxxxx>");
+MODULE_DESCRIPTION("Intel Broxton PMIC Thermal Driver");
+MODULE_LICENSE("GPL v2");
-- 
1.9.1