drivers/thermal/intel_soc_dts_thermal.c

   1 /*
   2  * intel_soc_dts_thermal.c
   3  * Copyright (c) 2014, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  */
  15
  16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/module.h>
  19 #include <linux/interrupt.h>
  20 #include <asm/cpu_device_id.h>
  21 #include "intel_soc_dts_iosf.h"
  22
  23 #define CRITICAL_OFFSET_FROM_TJ_MAX     5000
  24
  25 static int crit_offset = CRITICAL_OFFSET_FROM_TJ_MAX;
  26 module_param(crit_offset, int, 0644);
  27 MODULE_PARM_DESC(crit_offset,
  28         "Critical Temperature offset from tj max in millidegree Celsius.");
  29
  30 /* IRQ 86 is a fixed APIC interrupt for BYT DTS Aux threshold notifications */
  31 #define BYT_SOC_DTS_APIC_IRQ    86
  32
  33 static int soc_dts_thres_irq;
  34 static struct intel_soc_dts_sensors *soc_dts;
  35
  36 static irqreturn_t soc_irq_thread_fn(int irq, void *dev_data)
  37 {
  38         pr_debug("proc_thermal_interrupt\n");
  39         intel_soc_dts_iosf_interrupt_handler(soc_dts);
  40
  41         return IRQ_HANDLED;
  42 }
  43
  44 static const struct x86_cpu_id soc_thermal_ids[] = {
  45         { X86_VENDOR_INTEL, X86_FAMILY_ANY, 0x37, 0, BYT_SOC_DTS_APIC_IRQ},
  46         {}
  47 };
  48 MODULE_DEVICE_TABLE(x86cpu, soc_thermal_ids);
  49
  50 static int __init intel_soc_thermal_init(void)
  51 {
  52         int err = 0;
  53         const struct x86_cpu_id *match_cpu;
  54
  55         match_cpu = x86_match_cpu(soc_thermal_ids);
  56         if (!match_cpu)
  57                 return -ENODEV;
  58
  59         /* Create a zone with 2 trips with marked as read only */
  60         soc_dts = intel_soc_dts_iosf_init(INTEL_SOC_DTS_INTERRUPT_APIC, 2, 1);
  61         if (IS_ERR(soc_dts)) {
  62                 err = PTR_ERR(soc_dts);
  63                 return err;
  64         }
  65
  66         soc_dts_thres_irq = (int)match_cpu->driver_data;
  67
  68         if (soc_dts_thres_irq) {
  69                 err = request_threaded_irq(soc_dts_thres_irq, NULL,
  70                                            soc_irq_thread_fn,
  71                                            IRQF_TRIGGER_RISING | IRQF_ONESHOT,
  72                                            "soc_dts", soc_dts);
  73                 if (err) {
  74                         pr_err("request_threaded_irq ret %d\n", err);
  75                         goto error_irq;
  76                 }
  77         }
  78
  79         err = intel_soc_dts_iosf_add_read_only_critical_trip(soc_dts,
  80                                                              crit_offset);
  81         if (err)
  82                 goto error_trips;
  83
  84         return 0;
  85
  86 error_trips:
  87         if (soc_dts_thres_irq)
  88                 free_irq(soc_dts_thres_irq, soc_dts);
  89 error_irq:
  90         intel_soc_dts_iosf_exit(soc_dts);
  91
  92         return err;
  93 }
  94
  95 static void __exit intel_soc_thermal_exit(void)
  96 {
  97         if (soc_dts_thres_irq)
  98                 free_irq(soc_dts_thres_irq, soc_dts);
  99         intel_soc_dts_iosf_exit(soc_dts);
 100 }
 101
 102 module_init(intel_soc_thermal_init)
 103 module_exit(intel_soc_thermal_exit)
 104
 105 MODULE_DESCRIPTION("Intel SoC DTS Thermal Driver");
 106 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
 107 MODULE_LICENSE("GPL v2");