LXR linux/drivers/thermal/broadcom/sr-thermal.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2018 Broadcom
   4 */
   5
   6#include <linux/module.h>
   7#include <linux/of_address.h>
   8#include <linux/platform_device.h>
   9#include <linux/thermal.h>
  10
  11/*
  12 * In stingray thermal IO memory,
  13 * Total Number of available TMONs MASK is at offset 0
  14 * temperature registers BASE is at 4 byte offset.
  15 * Each TMON temperature register size is 4.
  16 */
  17#define SR_TMON_TEMP_BASE(id)   ((id) * 0x4)
  18
  19#define SR_TMON_MAX_LIST        6
  20
  21struct sr_tmon {
  22        struct thermal_zone_device *tz;
  23        unsigned int crit_temp;
  24        unsigned int tmon_id;
  25        struct sr_thermal *priv;
  26};
  27
  28struct sr_thermal {
  29        void __iomem *regs;
  30        unsigned int max_crit_temp;
  31        struct sr_tmon tmon[SR_TMON_MAX_LIST];
  32};
  33
  34static int sr_get_temp(void *data, int *temp)
  35{
  36        struct sr_tmon *tmon = data;
  37        struct sr_thermal *sr_thermal = tmon->priv;
  38
  39        *temp = readl(sr_thermal->regs + SR_TMON_TEMP_BASE(tmon->tmon_id));
  40
  41        return 0;
  42}
  43
  44static const struct thermal_zone_of_device_ops sr_tz_ops = {
  45        .get_temp = sr_get_temp,
  46};
  47
  48static int sr_thermal_probe(struct platform_device *pdev)
  49{
  50        struct device *dev = &pdev->dev;
  51        struct sr_thermal *sr_thermal;
  52        struct sr_tmon *tmon;
  53        struct resource *res;
  54        u32 sr_tmon_list = 0;
  55        unsigned int i;
  56        int ret;
  57
  58        sr_thermal = devm_kzalloc(dev, sizeof(*sr_thermal), GFP_KERNEL);
  59        if (!sr_thermal)
  60                return -ENOMEM;
  61
  62        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  63        sr_thermal->regs = (void __iomem *)devm_memremap(&pdev->dev, res->start,
  64                                                         resource_size(res),
  65                                                         MEMREMAP_WB);
  66        if (IS_ERR(sr_thermal->regs)) {
  67                dev_err(dev, "failed to get io address\n");
  68                return PTR_ERR(sr_thermal->regs);
  69        }
  70
  71        ret = device_property_read_u32(dev, "brcm,tmon-mask", &sr_tmon_list);
  72        if (ret)
  73                return ret;
  74
  75        tmon = sr_thermal->tmon;
  76        for (i = 0; i < SR_TMON_MAX_LIST; i++, tmon++) {
  77                if (!(sr_tmon_list & BIT(i)))
  78                        continue;
  79
  80                /* Flush temperature registers */
  81                writel(0, sr_thermal->regs + SR_TMON_TEMP_BASE(i));
  82                tmon->tmon_id = i;
  83                tmon->priv = sr_thermal;
  84                tmon->tz = devm_thermal_zone_of_sensor_register(dev, i, tmon,
  85                                                                &sr_tz_ops);
  86                if (IS_ERR(tmon->tz))
  87                        return PTR_ERR(tmon->tz);
  88
  89                dev_dbg(dev, "thermal sensor %d registered\n", i);
  90        }
  91        platform_set_drvdata(pdev, sr_thermal);
  92
  93        return 0;
  94}
  95
  96static const struct of_device_id sr_thermal_of_match[] = {
  97        { .compatible = "brcm,sr-thermal", },
  98        {},
  99};
 100MODULE_DEVICE_TABLE(of, sr_thermal_of_match);
 101
 102static struct platform_driver sr_thermal_driver = {
 103        .probe          = sr_thermal_probe,
 104        .driver = {
 105                .name = "sr-thermal",
 106                .of_match_table = sr_thermal_of_match,
 107        },
 108};
 109module_platform_driver(sr_thermal_driver);
 110
 111MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
 112MODULE_DESCRIPTION("Stingray thermal driver");
 113MODULE_LICENSE("GPL v2");
 114