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path: root/drivers/thermal/qcom/tsens-common.c
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Diffstat (limited to 'drivers/thermal/qcom/tsens-common.c')
-rw-r--r--drivers/thermal/qcom/tsens-common.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/drivers/thermal/qcom/tsens-common.c b/drivers/thermal/qcom/tsens-common.c
new file mode 100644
index 000000000000..4a1af151bd53
--- /dev/null
+++ b/drivers/thermal/qcom/tsens-common.c
@@ -0,0 +1,141 @@
+/*
+ * 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/err.h>
+#include <linux/io.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include "tsens.h"
+
+#define S0_ST_ADDR 0x1030
+#define SN_ADDR_OFFSET 0x4
+#define SN_ST_TEMP_MASK 0x3ff
+#define CAL_DEGC_PT1 30
+#define CAL_DEGC_PT2 120
+#define SLOPE_FACTOR 1000
+#define SLOPE_DEFAULT 3200
+
+char *qfprom_read(struct device *dev, const char *cname)
+{
+ struct nvmem_cell *cell;
+ ssize_t data;
+ char *ret;
+
+ cell = nvmem_cell_get(dev, cname);
+ if (IS_ERR(cell))
+ return ERR_CAST(cell);
+
+ ret = nvmem_cell_read(cell, &data);
+ nvmem_cell_put(cell);
+
+ return ret;
+}
+
+/*
+ * Use this function on devices where slope and offset calculations
+ * depend on calibration data read from qfprom. On others the slope
+ * and offset values are derived from tz->tzp->slope and tz->tzp->offset
+ * resp.
+ */
+void compute_intercept_slope(struct tsens_device *tmdev, u32 *p1,
+ u32 *p2, u32 mode)
+{
+ int i;
+ int num, den;
+
+ for (i = 0; i < tmdev->num_sensors; i++) {
+ dev_dbg(tmdev->dev,
+ "sensor%d - data_point1:%#x data_point2:%#x\n",
+ i, p1[i], p2[i]);
+
+ tmdev->sensor[i].slope = SLOPE_DEFAULT;
+ if (mode == TWO_PT_CALIB) {
+ /*
+ * slope (m) = adc_code2 - adc_code1 (y2 - y1)/
+ * temp_120_degc - temp_30_degc (x2 - x1)
+ */
+ num = p2[i] - p1[i];
+ num *= SLOPE_FACTOR;
+ den = CAL_DEGC_PT2 - CAL_DEGC_PT1;
+ tmdev->sensor[i].slope = num / den;
+ }
+
+ tmdev->sensor[i].offset = (p1[i] * SLOPE_FACTOR) -
+ (CAL_DEGC_PT1 *
+ tmdev->sensor[i].slope);
+ dev_dbg(tmdev->dev, "offset:%d\n", tmdev->sensor[i].offset);
+ }
+}
+
+static inline int code_to_degc(u32 adc_code, const struct tsens_sensor *s)
+{
+ int degc, num, den;
+
+ num = (adc_code * SLOPE_FACTOR) - s->offset;
+ den = s->slope;
+
+ if (num > 0)
+ degc = num + (den / 2);
+ else if (num < 0)
+ degc = num - (den / 2);
+ else
+ degc = num;
+
+ degc /= den;
+
+ return degc;
+}
+
+int get_temp_common(struct tsens_device *tmdev, int id, int *temp)
+{
+ struct tsens_sensor *s = &tmdev->sensor[id];
+ u32 code;
+ unsigned int sensor_addr;
+ int last_temp = 0, ret;
+
+ sensor_addr = S0_ST_ADDR + s->hw_id * SN_ADDR_OFFSET;
+ ret = regmap_read(tmdev->map, sensor_addr, &code);
+ if (ret)
+ return ret;
+ last_temp = code & SN_ST_TEMP_MASK;
+
+ *temp = code_to_degc(last_temp, s) * 1000;
+
+ return 0;
+}
+
+static const struct regmap_config tsens_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
+int __init init_common(struct tsens_device *tmdev)
+{
+ void __iomem *base;
+
+ base = of_iomap(tmdev->dev->of_node, 0);
+ if (IS_ERR(base))
+ return -EINVAL;
+
+ tmdev->map = devm_regmap_init_mmio(tmdev->dev, base, &tsens_config);
+ if (!tmdev->map) {
+ iounmap(base);
+ return -ENODEV;
+ }
+
+ return 0;
+}