/* * 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 #include #include #include #include #include #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 (!base) return -EINVAL; tmdev->map = devm_regmap_init_mmio(tmdev->dev, base, &tsens_config); if (IS_ERR(tmdev->map)) { iounmap(base); return PTR_ERR(tmdev->map); } return 0; } p;showmsg=1'>Expand)AuthorFilesLines