drivers/thermal/broadcom/sr-thermal.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2018 Broadcom
   4  */
   5
   6 #include <linux/acpi.h>
   7 #include <linux/module.h>
   8 #include <linux/of_address.h>
   9 #include <linux/platform_device.h>
  10 #include <linux/thermal.h>
  11
  12 /*
  13  * In stingray thermal IO memory,
  14  * Total Number of available TMONs MASK is at offset 0
  15  * temperature registers BASE is at 4 byte offset.
  16  * Each TMON temperature register size is 4.
  17  */
  18 #define SR_TMON_TEMP_BASE(id)   ((id) * 0x4)
  19
  20 #define SR_TMON_MAX_LIST        6
  21
  22 struct sr_tmon {
  23         struct thermal_zone_device *tz;
  24         unsigned int crit_temp;
  25         unsigned int tmon_id;
  26         struct sr_thermal *priv;
  27 };
  28
  29 struct sr_thermal {
  30         void __iomem *regs;
  31         unsigned int max_crit_temp;
  32         struct sr_tmon tmon[SR_TMON_MAX_LIST];
  33 };
  34
  35 static int sr_get_temp(void *data, int *temp)
  36 {
  37         struct sr_tmon *tmon = data;
  38         struct sr_thermal *sr_thermal = tmon->priv;
  39
  40         *temp = readl(sr_thermal->regs + SR_TMON_TEMP_BASE(tmon->tmon_id));
  41
  42         return 0;
  43 }
  44
  45 static const struct thermal_zone_of_device_ops sr_tz_ops = {
  46         .get_temp = sr_get_temp,
  47 };
  48
  49 static int sr_thermal_probe(struct platform_device *pdev)
  50 {
  51         struct device *dev = &pdev->dev;
  52         struct sr_thermal *sr_thermal;
  53         struct sr_tmon *tmon;
  54         struct resource *res;
  55         u32 sr_tmon_list = 0;
  56         unsigned int i;
  57         int ret;
  58
  59         sr_thermal = devm_kzalloc(dev, sizeof(*sr_thermal), GFP_KERNEL);
  60         if (!sr_thermal)
  61                 return -ENOMEM;
  62
  63         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  64         sr_thermal->regs = (void __iomem *)devm_memremap(&pdev->dev, res->start,
  65                                                          resource_size(res),
  66                                                          MEMREMAP_WB);
  67         if (IS_ERR(sr_thermal->regs)) {
  68                 dev_err(dev, "failed to get io address\n");
  69                 return PTR_ERR(sr_thermal->regs);
  70         }
  71
  72         ret = device_property_read_u32(dev, "brcm,tmon-mask", &sr_tmon_list);
  73         if (ret)
  74                 return ret;
  75
  76         tmon = sr_thermal->tmon;
  77         for (i = 0; i < SR_TMON_MAX_LIST; i++, tmon++) {
  78                 if (!(sr_tmon_list & BIT(i)))
  79                         continue;
  80
  81                 /* Flush temperature registers */
  82                 writel(0, sr_thermal->regs + SR_TMON_TEMP_BASE(i));
  83                 tmon->tmon_id = i;
  84                 tmon->priv = sr_thermal;
  85                 tmon->tz = devm_thermal_zone_of_sensor_register(dev, i, tmon,
  86                                                                 &sr_tz_ops);
  87                 if (IS_ERR(tmon->tz))
  88                         return PTR_ERR(tmon->tz);
  89
  90                 dev_dbg(dev, "thermal sensor %d registered\n", i);
  91         }
  92         platform_set_drvdata(pdev, sr_thermal);
  93
  94         return 0;
  95 }
  96
  97 static const struct of_device_id sr_thermal_of_match[] = {
  98         { .compatible = "brcm,sr-thermal", },
  99         {},
 100 };
 101 MODULE_DEVICE_TABLE(of, sr_thermal_of_match);
 102
 103 static const struct acpi_device_id sr_thermal_acpi_ids[] = {
 104         { .id = "BRCM0500" },
 105         { /* sentinel */ }
 106 };
 107 MODULE_DEVICE_TABLE(acpi, sr_thermal_acpi_ids);
 108
 109 static struct platform_driver sr_thermal_driver = {
 110         .probe          = sr_thermal_probe,
 111         .driver = {
 112                 .name = "sr-thermal",
 113                 .of_match_table = sr_thermal_of_match,
 114                 .acpi_match_table = ACPI_PTR(sr_thermal_acpi_ids),
 115         },
 116 };
 117 module_platform_driver(sr_thermal_driver);
 118
 119 MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
 120 MODULE_DESCRIPTION("Stingray thermal driver");
 121 MODULE_LICENSE("GPL v2");