thermal: qcom: tsens-8916: Add support for 8916 family of SoCs

Add support to calibrate sensors on 8916 family and also add common
functions to read temperature from sensors (This can be reused on
other SoCs having similar TSENS device)
The calibration data is read from eeprom using the generic nvmem
framework apis.

Based on the original code by Siddartha Mohanadoss and Stephen Boyd.
Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

drivers/thermal/qcom/Makefile

 obj-$(CONFIG_QCOM_TSENS)	+= qcom_tsens.o
-qcom_tsens-y			+= tsens.o tsens-common.o
+qcom_tsens-y			+= tsens.o tsens-common.o tsens-8916.o

drivers/thermal/qcom/tsens-8916.c

+/*
+ * Copyright (c) 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/platform_device.h>
+#include "tsens.h"
+
+/* eeprom layout data for 8916 */
+#define BASE0_MASK	0x0000007f
+#define BASE1_MASK	0xfe000000
+#define BASE0_SHIFT	0
+#define BASE1_SHIFT	25
+
+#define S0_P1_MASK	0x00000f80
+#define S1_P1_MASK	0x003e0000
+#define S2_P1_MASK	0xf8000000
+#define S3_P1_MASK	0x000003e0
+#define S4_P1_MASK	0x000f8000
+
+#define S0_P2_MASK	0x0001f000
+#define S1_P2_MASK	0x07c00000
+#define S2_P2_MASK	0x0000001f
+#define S3_P2_MASK	0x00007c00
+#define S4_P2_MASK	0x01f00000
+
+#define S0_P1_SHIFT	7
+#define S1_P1_SHIFT	17
+#define S2_P1_SHIFT	27
+#define S3_P1_SHIFT	5
+#define S4_P1_SHIFT	15
+
+#define S0_P2_SHIFT	12
+#define S1_P2_SHIFT	22
+#define S2_P2_SHIFT	0
+#define S3_P2_SHIFT	10
+#define S4_P2_SHIFT	20
+
+#define CAL_SEL_MASK	0xe0000000
+#define CAL_SEL_SHIFT	29
+
+static int calibrate_8916(struct tsens_device *tmdev)
+{
+	int base0 = 0, base1 = 0, i;
+	u32 p1[5], p2[5];
+	int mode = 0;
+	u32 *qfprom_cdata, *qfprom_csel;
+
+	qfprom_cdata = (u32 *)qfprom_read(tmdev->dev, "calib");
+	if (IS_ERR(qfprom_cdata))
+		return PTR_ERR(qfprom_cdata);
+
+	qfprom_csel = (u32 *)qfprom_read(tmdev->dev, "calib_sel");
+	if (IS_ERR(qfprom_csel))
+		return PTR_ERR(qfprom_csel);
+
+	mode = (qfprom_csel[0] & CAL_SEL_MASK) >> CAL_SEL_SHIFT;
+	dev_dbg(tmdev->dev, "calibration mode is %d\n", mode);
+
+	switch (mode) {
+	case TWO_PT_CALIB:
+		base1 = (qfprom_cdata[1] & BASE1_MASK) >> BASE1_SHIFT;
+		p2[0] = (qfprom_cdata[0] & S0_P2_MASK) >> S0_P2_SHIFT;
+		p2[1] = (qfprom_cdata[0] & S1_P2_MASK) >> S1_P2_SHIFT;
+		p2[2] = (qfprom_cdata[1] & S2_P2_MASK) >> S2_P2_SHIFT;
+		p2[3] = (qfprom_cdata[1] & S3_P2_MASK) >> S3_P2_SHIFT;
+		p2[4] = (qfprom_cdata[1] & S4_P2_MASK) >> S4_P2_SHIFT;
+		for (i = 0; i < tmdev->num_sensors; i++)
+			p2[i] = ((base1 + p2[i]) << 3);
+		/* Fall through */
+	case ONE_PT_CALIB2:
+		base0 = (qfprom_cdata[0] & BASE0_MASK);
+		p1[0] = (qfprom_cdata[0] & S0_P1_MASK) >> S0_P1_SHIFT;
+		p1[1] = (qfprom_cdata[0] & S1_P1_MASK) >> S1_P1_SHIFT;
+		p1[2] = (qfprom_cdata[0] & S2_P1_MASK) >> S2_P1_SHIFT;
+		p1[3] = (qfprom_cdata[1] & S3_P1_MASK) >> S3_P1_SHIFT;
+		p1[4] = (qfprom_cdata[1] & S4_P1_MASK) >> S4_P1_SHIFT;
+		for (i = 0; i < tmdev->num_sensors; i++)
+			p1[i] = (((base0) + p1[i]) << 3);
+		break;
+	default:
+		for (i = 0; i < tmdev->num_sensors; i++) {
+			p1[i] = 500;
+			p2[i] = 780;
+		}
+		break;
+	}
+
+	compute_intercept_slope(tmdev, p1, p2, mode);
+
+	return 0;
+}
+
+const struct tsens_ops ops_8916 = {
+	.init		= init_common,
+	.calibrate	= calibrate_8916,
+	.get_temp	= get_temp_common,
+};
+
+const struct tsens_data data_8916 = {
+	.num_sensors	= 5,
+	.ops		= &ops_8916,
+	.hw_ids		= (unsigned int []){0, 1, 2, 4, 5 },
+};

drivers/thermal/qcom/tsens.c

@@ -65,6 +65,7 @@ static SIMPLE_DEV_PM_OPS(tsens_pm_ops, tsens_suspend, tsens_resume);
 static const struct of_device_id tsens_table[] = {
 	{
 		.compatible = "qcom,msm8916-tsens",
+		.data = &data_8916,
 	}, {
 		.compatible = "qcom,msm8974-tsens",
 	},

drivers/thermal/qcom/tsens.h

@@ -87,4 +87,6 @@ void compute_intercept_slope(struct tsens_device *, u32 *, u32 *, u32);
 int init_common(struct tsens_device *);
 int get_temp_common(struct tsens_device *, int, int *);
 
+extern const struct tsens_data data_8916;
+
 #endif /* __QCOM_TSENS_H__ */