root/drivers/thermal/broadcom/brcmstb_thermal.c

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DEFINITIONS

This source file includes following definitions.
  1. avs_tmon_code_to_temp
  2. avs_tmon_temp_to_code
  3. brcmstb_get_temp
  4. avs_tmon_trip_enable
  5. avs_tmon_get_trip_temp
  6. avs_tmon_set_trip_temp
  7. avs_tmon_get_intr_temp
  8. brcmstb_tmon_irq_thread
  9. brcmstb_set_trips
  10. brcmstb_thermal_probe

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Broadcom STB AVS TMON thermal sensor driver
   4  *
   5  * Copyright (c) 2015-2017 Broadcom
   6  */
   7 
   8 #define DRV_NAME        "brcmstb_thermal"
   9 
  10 #define pr_fmt(fmt)     DRV_NAME ": " fmt
  11 
  12 #include <linux/bitops.h>
  13 #include <linux/device.h>
  14 #include <linux/err.h>
  15 #include <linux/io.h>
  16 #include <linux/irqreturn.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/of_device.h>
  22 #include <linux/thermal.h>
  23 
  24 #define AVS_TMON_STATUS                 0x00
  25  #define AVS_TMON_STATUS_valid_msk      BIT(11)
  26  #define AVS_TMON_STATUS_data_msk       GENMASK(10, 1)
  27  #define AVS_TMON_STATUS_data_shift     1
  28 
  29 #define AVS_TMON_EN_OVERTEMP_RESET      0x04
  30  #define AVS_TMON_EN_OVERTEMP_RESET_msk BIT(0)
  31 
  32 #define AVS_TMON_RESET_THRESH           0x08
  33  #define AVS_TMON_RESET_THRESH_msk      GENMASK(10, 1)
  34  #define AVS_TMON_RESET_THRESH_shift    1
  35 
  36 #define AVS_TMON_INT_IDLE_TIME          0x10
  37 
  38 #define AVS_TMON_EN_TEMP_INT_SRCS       0x14
  39  #define AVS_TMON_EN_TEMP_INT_SRCS_high BIT(1)
  40  #define AVS_TMON_EN_TEMP_INT_SRCS_low  BIT(0)
  41 
  42 #define AVS_TMON_INT_THRESH             0x18
  43  #define AVS_TMON_INT_THRESH_high_msk   GENMASK(26, 17)
  44  #define AVS_TMON_INT_THRESH_high_shift 17
  45  #define AVS_TMON_INT_THRESH_low_msk    GENMASK(10, 1)
  46  #define AVS_TMON_INT_THRESH_low_shift  1
  47 
  48 #define AVS_TMON_TEMP_INT_CODE          0x1c
  49 #define AVS_TMON_TP_TEST_ENABLE         0x20
  50 
  51 /* Default coefficients */
  52 #define AVS_TMON_TEMP_SLOPE             487
  53 #define AVS_TMON_TEMP_OFFSET            410040
  54 
  55 /* HW related temperature constants */
  56 #define AVS_TMON_TEMP_MAX               0x3ff
  57 #define AVS_TMON_TEMP_MIN               -88161
  58 #define AVS_TMON_TEMP_MASK              AVS_TMON_TEMP_MAX
  59 
  60 enum avs_tmon_trip_type {
  61         TMON_TRIP_TYPE_LOW = 0,
  62         TMON_TRIP_TYPE_HIGH,
  63         TMON_TRIP_TYPE_RESET,
  64         TMON_TRIP_TYPE_MAX,
  65 };
  66 
  67 struct avs_tmon_trip {
  68         /* HW bit to enable the trip */
  69         u32 enable_offs;
  70         u32 enable_mask;
  71 
  72         /* HW field to read the trip temperature */
  73         u32 reg_offs;
  74         u32 reg_msk;
  75         int reg_shift;
  76 };
  77 
  78 static struct avs_tmon_trip avs_tmon_trips[] = {
  79         /* Trips when temperature is below threshold */
  80         [TMON_TRIP_TYPE_LOW] = {
  81                 .enable_offs    = AVS_TMON_EN_TEMP_INT_SRCS,
  82                 .enable_mask    = AVS_TMON_EN_TEMP_INT_SRCS_low,
  83                 .reg_offs       = AVS_TMON_INT_THRESH,
  84                 .reg_msk        = AVS_TMON_INT_THRESH_low_msk,
  85                 .reg_shift      = AVS_TMON_INT_THRESH_low_shift,
  86         },
  87         /* Trips when temperature is above threshold */
  88         [TMON_TRIP_TYPE_HIGH] = {
  89                 .enable_offs    = AVS_TMON_EN_TEMP_INT_SRCS,
  90                 .enable_mask    = AVS_TMON_EN_TEMP_INT_SRCS_high,
  91                 .reg_offs       = AVS_TMON_INT_THRESH,
  92                 .reg_msk        = AVS_TMON_INT_THRESH_high_msk,
  93                 .reg_shift      = AVS_TMON_INT_THRESH_high_shift,
  94         },
  95         /* Automatically resets chip when above threshold */
  96         [TMON_TRIP_TYPE_RESET] = {
  97                 .enable_offs    = AVS_TMON_EN_OVERTEMP_RESET,
  98                 .enable_mask    = AVS_TMON_EN_OVERTEMP_RESET_msk,
  99                 .reg_offs       = AVS_TMON_RESET_THRESH,
 100                 .reg_msk        = AVS_TMON_RESET_THRESH_msk,
 101                 .reg_shift      = AVS_TMON_RESET_THRESH_shift,
 102         },
 103 };
 104 
 105 struct brcmstb_thermal_priv {
 106         void __iomem *tmon_base;
 107         struct device *dev;
 108         struct thermal_zone_device *thermal;
 109 };
 110 
 111 /* Convert a HW code to a temperature reading (millidegree celsius) */
 112 static inline int avs_tmon_code_to_temp(struct thermal_zone_device *tz,
 113                                         u32 code)
 114 {
 115         return (AVS_TMON_TEMP_OFFSET -
 116                 (int)((code & AVS_TMON_TEMP_MAX) * AVS_TMON_TEMP_SLOPE));
 117 }
 118 
 119 /*
 120  * Convert a temperature value (millidegree celsius) to a HW code
 121  *
 122  * @temp: temperature to convert
 123  * @low: if true, round toward the low side
 124  */
 125 static inline u32 avs_tmon_temp_to_code(struct thermal_zone_device *tz,
 126                                         int temp, bool low)
 127 {
 128         if (temp < AVS_TMON_TEMP_MIN)
 129                 return AVS_TMON_TEMP_MAX;       /* Maximum code value */
 130 
 131         if (temp >= AVS_TMON_TEMP_OFFSET)
 132                 return 0;       /* Minimum code value */
 133 
 134         if (low)
 135                 return (u32)(DIV_ROUND_UP(AVS_TMON_TEMP_OFFSET - temp,
 136                                           AVS_TMON_TEMP_SLOPE));
 137         else
 138                 return (u32)((AVS_TMON_TEMP_OFFSET - temp) /
 139                               AVS_TMON_TEMP_SLOPE);
 140 }
 141 
 142 static int brcmstb_get_temp(void *data, int *temp)
 143 {
 144         struct brcmstb_thermal_priv *priv = data;
 145         u32 val;
 146         long t;
 147 
 148         val = __raw_readl(priv->tmon_base + AVS_TMON_STATUS);
 149 
 150         if (!(val & AVS_TMON_STATUS_valid_msk)) {
 151                 dev_err(priv->dev, "reading not valid\n");
 152                 return -EIO;
 153         }
 154 
 155         val = (val & AVS_TMON_STATUS_data_msk) >> AVS_TMON_STATUS_data_shift;
 156 
 157         t = avs_tmon_code_to_temp(priv->thermal, val);
 158         if (t < 0)
 159                 *temp = 0;
 160         else
 161                 *temp = t;
 162 
 163         return 0;
 164 }
 165 
 166 static void avs_tmon_trip_enable(struct brcmstb_thermal_priv *priv,
 167                                  enum avs_tmon_trip_type type, int en)
 168 {
 169         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 170         u32 val = __raw_readl(priv->tmon_base + trip->enable_offs);
 171 
 172         dev_dbg(priv->dev, "%sable trip, type %d\n", en ? "en" : "dis", type);
 173 
 174         if (en)
 175                 val |= trip->enable_mask;
 176         else
 177                 val &= ~trip->enable_mask;
 178 
 179         __raw_writel(val, priv->tmon_base + trip->enable_offs);
 180 }
 181 
 182 static int avs_tmon_get_trip_temp(struct brcmstb_thermal_priv *priv,
 183                                   enum avs_tmon_trip_type type)
 184 {
 185         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 186         u32 val = __raw_readl(priv->tmon_base + trip->reg_offs);
 187 
 188         val &= trip->reg_msk;
 189         val >>= trip->reg_shift;
 190 
 191         return avs_tmon_code_to_temp(priv->thermal, val);
 192 }
 193 
 194 static void avs_tmon_set_trip_temp(struct brcmstb_thermal_priv *priv,
 195                                    enum avs_tmon_trip_type type,
 196                                    int temp)
 197 {
 198         struct avs_tmon_trip *trip = &avs_tmon_trips[type];
 199         u32 val, orig;
 200 
 201         dev_dbg(priv->dev, "set temp %d to %d\n", type, temp);
 202 
 203         /* round toward low temp for the low interrupt */
 204         val = avs_tmon_temp_to_code(priv->thermal, temp,
 205                                     type == TMON_TRIP_TYPE_LOW);
 206 
 207         val <<= trip->reg_shift;
 208         val &= trip->reg_msk;
 209 
 210         orig = __raw_readl(priv->tmon_base + trip->reg_offs);
 211         orig &= ~trip->reg_msk;
 212         orig |= val;
 213         __raw_writel(orig, priv->tmon_base + trip->reg_offs);
 214 }
 215 
 216 static int avs_tmon_get_intr_temp(struct brcmstb_thermal_priv *priv)
 217 {
 218         u32 val;
 219 
 220         val = __raw_readl(priv->tmon_base + AVS_TMON_TEMP_INT_CODE);
 221         return avs_tmon_code_to_temp(priv->thermal, val);
 222 }
 223 
 224 static irqreturn_t brcmstb_tmon_irq_thread(int irq, void *data)
 225 {
 226         struct brcmstb_thermal_priv *priv = data;
 227         int low, high, intr;
 228 
 229         low = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_LOW);
 230         high = avs_tmon_get_trip_temp(priv, TMON_TRIP_TYPE_HIGH);
 231         intr = avs_tmon_get_intr_temp(priv);
 232 
 233         dev_dbg(priv->dev, "low/intr/high: %d/%d/%d\n",
 234                         low, intr, high);
 235 
 236         /* Disable high-temp until next threshold shift */
 237         if (intr >= high)
 238                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
 239         /* Disable low-temp until next threshold shift */
 240         if (intr <= low)
 241                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
 242 
 243         /*
 244          * Notify using the interrupt temperature, in case the temperature
 245          * changes before it can next be read out
 246          */
 247         thermal_zone_device_update(priv->thermal, intr);
 248 
 249         return IRQ_HANDLED;
 250 }
 251 
 252 static int brcmstb_set_trips(void *data, int low, int high)
 253 {
 254         struct brcmstb_thermal_priv *priv = data;
 255 
 256         dev_dbg(priv->dev, "set trips %d <--> %d\n", low, high);
 257 
 258         /*
 259          * Disable low-temp if "low" is too small. As per thermal framework
 260          * API, we use -INT_MAX rather than INT_MIN.
 261          */
 262         if (low <= -INT_MAX) {
 263                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 0);
 264         } else {
 265                 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_LOW, low);
 266                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_LOW, 1);
 267         }
 268 
 269         /* Disable high-temp if "high" is too big. */
 270         if (high == INT_MAX) {
 271                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 0);
 272         } else {
 273                 avs_tmon_set_trip_temp(priv, TMON_TRIP_TYPE_HIGH, high);
 274                 avs_tmon_trip_enable(priv, TMON_TRIP_TYPE_HIGH, 1);
 275         }
 276 
 277         return 0;
 278 }
 279 
 280 static const struct thermal_zone_of_device_ops of_ops = {
 281         .get_temp       = brcmstb_get_temp,
 282         .set_trips      = brcmstb_set_trips,
 283 };
 284 
 285 static const struct of_device_id brcmstb_thermal_id_table[] = {
 286         { .compatible = "brcm,avs-tmon" },
 287         {},
 288 };
 289 MODULE_DEVICE_TABLE(of, brcmstb_thermal_id_table);
 290 
 291 static int brcmstb_thermal_probe(struct platform_device *pdev)
 292 {
 293         struct thermal_zone_device *thermal;
 294         struct brcmstb_thermal_priv *priv;
 295         struct resource *res;
 296         int irq, ret;
 297 
 298         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 299         if (!priv)
 300                 return -ENOMEM;
 301 
 302         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 303         priv->tmon_base = devm_ioremap_resource(&pdev->dev, res);
 304         if (IS_ERR(priv->tmon_base))
 305                 return PTR_ERR(priv->tmon_base);
 306 
 307         priv->dev = &pdev->dev;
 308         platform_set_drvdata(pdev, priv);
 309 
 310         thermal = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, priv,
 311                                                        &of_ops);
 312         if (IS_ERR(thermal)) {
 313                 ret = PTR_ERR(thermal);
 314                 dev_err(&pdev->dev, "could not register sensor: %d\n", ret);
 315                 return ret;
 316         }
 317 
 318         priv->thermal = thermal;
 319 
 320         irq = platform_get_irq(pdev, 0);
 321         if (irq < 0) {
 322                 dev_err(&pdev->dev, "could not get IRQ\n");
 323                 return irq;
 324         }
 325         ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 326                                         brcmstb_tmon_irq_thread, IRQF_ONESHOT,
 327                                         DRV_NAME, priv);
 328         if (ret < 0) {
 329                 dev_err(&pdev->dev, "could not request IRQ: %d\n", ret);
 330                 return ret;
 331         }
 332 
 333         dev_info(&pdev->dev, "registered AVS TMON of-sensor driver\n");
 334 
 335         return 0;
 336 }
 337 
 338 static struct platform_driver brcmstb_thermal_driver = {
 339         .probe = brcmstb_thermal_probe,
 340         .driver = {
 341                 .name = DRV_NAME,
 342                 .of_match_table = brcmstb_thermal_id_table,
 343         },
 344 };
 345 module_platform_driver(brcmstb_thermal_driver);
 346 
 347 MODULE_LICENSE("GPL v2");
 348 MODULE_AUTHOR("Brian Norris");
 349 MODULE_DESCRIPTION("Broadcom STB AVS TMON thermal driver");

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