1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/thermal/qcom-spmi-temp-alarm.c b/drivers/thermal/qcom-spmi-temp-alarm.c
new file mode 100644
index 0000000..c8d27b8
--- /dev/null
+++ b/drivers/thermal/qcom-spmi-temp-alarm.c
@@ -0,0 +1,309 @@
+/*
+ * Copyright (c) 2011-2015, The Linux Foundation. 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 and
+ * only 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/delay.h>
+#include <linux/err.h>
+#include <linux/iio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+#define QPNP_TM_REG_TYPE		0x04
+#define QPNP_TM_REG_SUBTYPE		0x05
+#define QPNP_TM_REG_STATUS		0x08
+#define QPNP_TM_REG_SHUTDOWN_CTRL1	0x40
+#define QPNP_TM_REG_ALARM_CTRL		0x46
+
+#define QPNP_TM_TYPE			0x09
+#define QPNP_TM_SUBTYPE			0x08
+
+#define STATUS_STAGE_MASK		0x03
+
+#define SHUTDOWN_CTRL1_THRESHOLD_MASK	0x03
+
+#define ALARM_CTRL_FORCE_ENABLE		0x80
+
+/*
+ * Trip point values based on threshold control
+ * 0 = {105 C, 125 C, 145 C}
+ * 1 = {110 C, 130 C, 150 C}
+ * 2 = {115 C, 135 C, 155 C}
+ * 3 = {120 C, 140 C, 160 C}
+*/
+#define TEMP_STAGE_STEP			20000	/* Stage step: 20.000 C */
+#define TEMP_STAGE_HYSTERESIS		2000
+
+#define TEMP_THRESH_MIN			105000	/* Threshold Min: 105 C */
+#define TEMP_THRESH_STEP		5000	/* Threshold step: 5 C */
+
+#define THRESH_MIN			0
+
+/* Temperature in Milli Celsius reported during stage 0 if no ADC is present */
+#define DEFAULT_TEMP			37000
+
+struct qpnp_tm_chip {
+	struct regmap			*map;
+	struct thermal_zone_device	*tz_dev;
+	long				temp;
+	unsigned int			thresh;
+	unsigned int			stage;
+	unsigned int			prev_stage;
+	unsigned int			base;
+	struct iio_channel		*adc;
+};
+
+static int qpnp_tm_read(struct qpnp_tm_chip *chip, u16 addr, u8 *data)
+{
+	unsigned int val;
+	int ret;
+
+	ret = regmap_read(chip->map, chip->base + addr, &val);
+	if (ret < 0)
+		return ret;
+
+	*data = val;
+	return 0;
+}
+
+static int qpnp_tm_write(struct qpnp_tm_chip *chip, u16 addr, u8 data)
+{
+	return regmap_write(chip->map, chip->base + addr, data);
+}
+
+/*
+ * This function updates the internal temp value based on the
+ * current thermal stage and threshold as well as the previous stage
+ */
+static int qpnp_tm_update_temp_no_adc(struct qpnp_tm_chip *chip)
+{
+	unsigned int stage;
+	int ret;
+	u8 reg = 0;
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
+	if (ret < 0)
+		return ret;
+
+	stage = reg & STATUS_STAGE_MASK;
+
+	if (stage > chip->stage) {
+		/* increasing stage, use lower bound */
+		chip->temp = (stage - 1) * TEMP_STAGE_STEP +
+			     chip->thresh * TEMP_THRESH_STEP +
+			     TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
+	} else if (stage < chip->stage) {
+		/* decreasing stage, use upper bound */
+		chip->temp = stage * TEMP_STAGE_STEP +
+			     chip->thresh * TEMP_THRESH_STEP -
+			     TEMP_STAGE_HYSTERESIS + TEMP_THRESH_MIN;
+	}
+
+	chip->stage = stage;
+
+	return 0;
+}
+
+static int qpnp_tm_get_temp(void *data, long *temp)
+{
+	struct qpnp_tm_chip *chip = data;
+	int ret, mili_celsius;
+
+	if (!temp)
+		return -EINVAL;
+
+	if (IS_ERR(chip->adc)) {
+		ret = qpnp_tm_update_temp_no_adc(chip);
+		if (ret < 0)
+			return ret;
+	} else {
+		ret = iio_read_channel_processed(chip->adc, &mili_celsius);
+		if (ret < 0)
+			return ret;
+
+		chip->temp = mili_celsius;
+	}
+
+	*temp = chip->temp < 0 ? 0 : chip->temp;
+
+	return 0;
+}
+
+static const struct thermal_zone_of_device_ops qpnp_tm_sensor_ops = {
+	.get_temp = qpnp_tm_get_temp,
+};
+
+static irqreturn_t qpnp_tm_isr(int irq, void *data)
+{
+	struct qpnp_tm_chip *chip = data;
+
+	thermal_zone_device_update(chip->tz_dev);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * This function initializes the internal temp value based on only the
+ * current thermal stage and threshold. Setup threshold control and
+ * disable shutdown override.
+ */
+static int qpnp_tm_init(struct qpnp_tm_chip *chip)
+{
+	int ret;
+	u8 reg;
+
+	chip->thresh = THRESH_MIN;
+	chip->temp = DEFAULT_TEMP;
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_STATUS, &reg);
+	if (ret < 0)
+		return ret;
+
+	chip->stage = reg & STATUS_STAGE_MASK;
+
+	if (chip->stage)
+		chip->temp = chip->thresh * TEMP_THRESH_STEP +
+			     (chip->stage - 1) * TEMP_STAGE_STEP +
+			     TEMP_THRESH_MIN;
+
+	/*
+	 * Set threshold and disable software override of stage 2 and 3
+	 * shutdowns.
+	 */
+	reg = chip->thresh & SHUTDOWN_CTRL1_THRESHOLD_MASK;
+	ret = qpnp_tm_write(chip, QPNP_TM_REG_SHUTDOWN_CTRL1, reg);
+	if (ret < 0)
+		return ret;
+
+	/* Enable the thermal alarm PMIC module in always-on mode. */
+	reg = ALARM_CTRL_FORCE_ENABLE;
+	ret = qpnp_tm_write(chip, QPNP_TM_REG_ALARM_CTRL, reg);
+
+	return ret;
+}
+
+static int qpnp_tm_probe(struct platform_device *pdev)
+{
+	struct qpnp_tm_chip *chip;
+	struct device_node *node;
+	u8 type, subtype;
+	u32 res[2];
+	int ret, irq;
+
+	node = pdev->dev.of_node;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	dev_set_drvdata(&pdev->dev, chip);
+
+	chip->map = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!chip->map)
+		return -ENXIO;
+
+	ret = of_property_read_u32_array(node, "reg", res, 2);
+	if (ret < 0)
+		return ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	/* ADC based measurements are optional */
+	chip->adc = iio_channel_get(&pdev->dev, "thermal");
+	if (PTR_ERR(chip->adc) == -EPROBE_DEFER)
+		return PTR_ERR(chip->adc);
+
+	chip->base = res[0];
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_TYPE, &type);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "could not read type\n");
+		goto fail;
+	}
+
+	ret = qpnp_tm_read(chip, QPNP_TM_REG_SUBTYPE, &subtype);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "could not read subtype\n");
+		goto fail;
+	}
+
+	if (type != QPNP_TM_TYPE || subtype != QPNP_TM_SUBTYPE) {
+		dev_err(&pdev->dev, "invalid type 0x%02x or subtype 0x%02x\n",
+			type, subtype);
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	ret = qpnp_tm_init(chip);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "init failed\n");
+		goto fail;
+	}
+
+	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, qpnp_tm_isr,
+					IRQF_ONESHOT, node->name, chip);
+	if (ret < 0)
+		goto fail;
+
+	chip->tz_dev = thermal_zone_of_sensor_register(&pdev->dev, 0, chip,
+							&qpnp_tm_sensor_ops);
+	if (IS_ERR(chip->tz_dev)) {
+		dev_err(&pdev->dev, "failed to register sensor\n");
+		ret = PTR_ERR(chip->tz_dev);
+		goto fail;
+	}
+
+	return 0;
+
+fail:
+	if (!IS_ERR(chip->adc))
+		iio_channel_release(chip->adc);
+
+	return ret;
+}
+
+static int qpnp_tm_remove(struct platform_device *pdev)
+{
+	struct qpnp_tm_chip *chip = dev_get_drvdata(&pdev->dev);
+
+	thermal_zone_of_sensor_unregister(&pdev->dev, chip->tz_dev);
+	if (!IS_ERR(chip->adc))
+		iio_channel_release(chip->adc);
+
+	return 0;
+}
+
+static const struct of_device_id qpnp_tm_match_table[] = {
+	{ .compatible = "qcom,spmi-temp-alarm" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, qpnp_tm_match_table);
+
+static struct platform_driver qpnp_tm_driver = {
+	.driver = {
+		.name = "spmi-temp-alarm",
+		.of_match_table = qpnp_tm_match_table,
+	},
+	.probe  = qpnp_tm_probe,
+	.remove = qpnp_tm_remove,
+};
+module_platform_driver(qpnp_tm_driver);
+
+MODULE_ALIAS("platform:spmi-temp-alarm");
+MODULE_DESCRIPTION("QPNP PMIC Temperature Alarm driver");
+MODULE_LICENSE("GPL v2");