drivers/thermal/qcom/tsens-v2.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2015, The Linux Foundation. All rights reserved.
   4  * Copyright (c) 2018, Linaro Limited
   5  */
   6
   7 #include <linux/regmap.h>
   8 #include <linux/bitops.h>
   9 #include "tsens.h"
  10
  11 #define STATUS_OFFSET           0xa0
  12 #define LAST_TEMP_MASK          0xfff
  13 #define STATUS_VALID_BIT        BIT(21)
  14
  15 static int get_temp_tsens_v2(struct tsens_device *tmdev, int id, int *temp)
  16 {
  17         struct tsens_sensor *s = &tmdev->sensor[id];
  18         u32 code;
  19         unsigned int status_reg;
  20         u32 last_temp = 0, last_temp2 = 0, last_temp3 = 0;
  21         int ret;
  22
  23         status_reg = tmdev->tm_offset + STATUS_OFFSET + s->hw_id * 4;
  24         ret = regmap_read(tmdev->map, status_reg, &code);
  25         if (ret)
  26                 return ret;
  27         last_temp = code & LAST_TEMP_MASK;
  28         if (code & STATUS_VALID_BIT)
  29                 goto done;
  30
  31         /* Try a second time */
  32         ret = regmap_read(tmdev->map, status_reg, &code);
  33         if (ret)
  34                 return ret;
  35         if (code & STATUS_VALID_BIT) {
  36                 last_temp = code & LAST_TEMP_MASK;
  37                 goto done;
  38         } else {
  39                 last_temp2 = code & LAST_TEMP_MASK;
  40         }
  41
  42         /* Try a third/last time */
  43         ret = regmap_read(tmdev->map, status_reg, &code);
  44         if (ret)
  45                 return ret;
  46         if (code & STATUS_VALID_BIT) {
  47                 last_temp = code & LAST_TEMP_MASK;
  48                 goto done;
  49         } else {
  50                 last_temp3 = code & LAST_TEMP_MASK;
  51         }
  52
  53         if (last_temp == last_temp2)
  54                 last_temp = last_temp2;
  55         else if (last_temp2 == last_temp3)
  56                 last_temp = last_temp3;
  57 done:
  58         /* Convert temperature from deciCelsius to milliCelsius */
  59         *temp = sign_extend32(last_temp, fls(LAST_TEMP_MASK) - 1) * 100;
  60
  61         return 0;
  62 }
  63
  64 static const struct tsens_ops ops_generic_v2 = {
  65         .init           = init_common,
  66         .get_temp       = get_temp_tsens_v2,
  67 };
  68
  69 const struct tsens_data data_tsens_v2 = {
  70         .ops            = &ops_generic_v2,
  71 };
  72
  73 /* Kept around for backward compatibility with old msm8996.dtsi */
  74 const struct tsens_data data_8996 = {
  75         .num_sensors    = 13,
  76         .ops            = &ops_generic_v2,
  77 };