drivers/hwmon/mc34vr500.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * An hwmon driver for the NXP MC34VR500 PMIC
   4  *
   5  * Author: Mario Kicherer <dev@kicherer.org>
   6  */
   7
   8 #include <linux/bits.h>
   9 #include <linux/dev_printk.h>
  10 #include <linux/device.h>
  11 #include <linux/err.h>
  12 #include <linux/errno.h>
  13 #include <linux/hwmon.h>
  14 #include <linux/i2c.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/irqreturn.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/regmap.h>
  20
  21 #define MC34VR500_I2C_ADDR              0x08
  22 #define MC34VR500_DEVICEID_VALUE        0x14
  23
  24 /* INTSENSE0 */
  25 #define ENS_BIT         BIT(0)
  26 #define LOWVINS_BIT     BIT(1)
  27 #define THERM110S_BIT   BIT(2)
  28 #define THERM120S_BIT   BIT(3)
  29 #define THERM125S_BIT   BIT(4)
  30 #define THERM130S_BIT   BIT(5)
  31
  32 #define MC34VR500_DEVICEID      0x00
  33
  34 #define MC34VR500_SILICONREVID  0x03
  35 #define MC34VR500_FABID         0x04
  36 #define MC34VR500_INTSTAT0      0x05
  37 #define MC34VR500_INTMASK0      0x06
  38 #define MC34VR500_INTSENSE0     0x07
  39
  40 struct mc34vr500_data {
  41         struct device *hwmon_dev;
  42         struct regmap *regmap;
  43 };
  44
  45 static irqreturn_t mc34vr500_process_interrupt(int irq, void *userdata)
  46 {
  47         struct mc34vr500_data *data = (struct mc34vr500_data *)userdata;
  48         unsigned int reg;
  49         int ret;
  50
  51         ret = regmap_read(data->regmap, MC34VR500_INTSTAT0, &reg);
  52         if (ret < 0)
  53                 return IRQ_HANDLED;
  54
  55         if (reg) {
  56                 if (reg & LOWVINS_BIT)
  57                         hwmon_notify_event(data->hwmon_dev, hwmon_in,
  58                                            hwmon_in_min_alarm, 0);
  59
  60                 if (reg & THERM110S_BIT)
  61                         hwmon_notify_event(data->hwmon_dev, hwmon_temp,
  62                                            hwmon_temp_max_alarm, 0);
  63
  64                 if (reg & THERM120S_BIT)
  65                         hwmon_notify_event(data->hwmon_dev, hwmon_temp,
  66                                            hwmon_temp_crit_alarm, 0);
  67
  68                 if (reg & THERM130S_BIT)
  69                         hwmon_notify_event(data->hwmon_dev, hwmon_temp,
  70                                            hwmon_temp_emergency_alarm, 0);
  71
  72                 /* write 1 to clear */
  73                 regmap_write(data->regmap, MC34VR500_INTSTAT0, LOWVINS_BIT |
  74                              THERM110S_BIT | THERM120S_BIT | THERM130S_BIT);
  75         }
  76
  77         return IRQ_HANDLED;
  78 }
  79
  80 static umode_t mc34vr500_is_visible(const void *data,
  81                                     enum hwmon_sensor_types type,
  82                                     u32 attr, int channel)
  83 {
  84         switch (attr) {
  85         case hwmon_in_min_alarm:
  86         case hwmon_temp_max_alarm:
  87         case hwmon_temp_crit_alarm:
  88         case hwmon_temp_emergency_alarm:
  89                 return 0444;
  90         default:
  91                 break;
  92         }
  93
  94         return 0;
  95 }
  96
  97 static int mc34vr500_alarm_read(struct mc34vr500_data *data, int index,
  98                                 long *val)
  99 {
 100         unsigned int reg;
 101         int ret;
 102
 103         ret = regmap_read(data->regmap, MC34VR500_INTSENSE0, &reg);
 104         if (ret < 0)
 105                 return ret;
 106
 107         *val = !!(reg & index);
 108
 109         return 0;
 110 }
 111
 112 static int mc34vr500_read(struct device *dev, enum hwmon_sensor_types type,
 113                           u32 attr, int channel, long *val)
 114 {
 115         struct mc34vr500_data *data = dev_get_drvdata(dev);
 116
 117         switch (type) {
 118         case hwmon_in:
 119                 switch (attr) {
 120                 case hwmon_in_min_alarm:
 121                         return mc34vr500_alarm_read(data, LOWVINS_BIT, val);
 122                 default:
 123                         return -EOPNOTSUPP;
 124                 }
 125         case hwmon_temp:
 126                 switch (attr) {
 127                 case hwmon_temp_max_alarm:
 128                         return mc34vr500_alarm_read(data, THERM110S_BIT, val);
 129                 case hwmon_temp_crit_alarm:
 130                         return mc34vr500_alarm_read(data, THERM120S_BIT, val);
 131                 case hwmon_temp_emergency_alarm:
 132                         return mc34vr500_alarm_read(data, THERM130S_BIT, val);
 133                 default:
 134                         return -EOPNOTSUPP;
 135                 }
 136         default:
 137                 return -EOPNOTSUPP;
 138         }
 139 }
 140
 141 static const struct hwmon_channel_info * const mc34vr500_info[] = {
 142         HWMON_CHANNEL_INFO(in, HWMON_I_MIN_ALARM),
 143         HWMON_CHANNEL_INFO(temp, HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM
 144                            | HWMON_T_EMERGENCY_ALARM),
 145         NULL,
 146 };
 147
 148 static const struct hwmon_ops mc34vr500_hwmon_ops = {
 149         .is_visible = mc34vr500_is_visible,
 150         .read = mc34vr500_read,
 151 };
 152
 153 static const struct hwmon_chip_info mc34vr500_chip_info = {
 154         .ops = &mc34vr500_hwmon_ops,
 155         .info = mc34vr500_info,
 156 };
 157
 158 static const struct regmap_config mc34vr500_regmap_config = {
 159         .reg_bits = 8,
 160         .val_bits = 8,
 161         .max_register = MC34VR500_INTSENSE0,
 162 };
 163
 164 static int mc34vr500_probe(struct i2c_client *client)
 165 {
 166         struct device *dev = &client->dev;
 167         struct mc34vr500_data *data;
 168         struct device *hwmon_dev;
 169         int ret;
 170         unsigned int reg, revid, fabid;
 171         struct regmap *regmap;
 172
 173         regmap = devm_regmap_init_i2c(client, &mc34vr500_regmap_config);
 174         if (IS_ERR(regmap))
 175                 return PTR_ERR(regmap);
 176
 177         data = devm_kzalloc(dev, sizeof(struct mc34vr500_data), GFP_KERNEL);
 178         if (!data)
 179                 return -ENOMEM;
 180
 181         data->regmap = regmap;
 182
 183         ret = regmap_read(regmap, MC34VR500_DEVICEID, &reg);
 184         if (ret < 0)
 185                 return ret;
 186
 187         if (reg != MC34VR500_DEVICEID_VALUE)
 188                 return -ENODEV;
 189
 190         ret = regmap_read(regmap, MC34VR500_SILICONREVID, &revid);
 191         if (ret < 0)
 192                 return ret;
 193
 194         ret = regmap_read(regmap, MC34VR500_FABID, &fabid);
 195         if (ret < 0)
 196                 return ret;
 197
 198         dev_dbg(dev, "mc34vr500: revid 0x%x fabid 0x%x\n", revid, fabid);
 199
 200         hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 201                                                          data,
 202                                                          &mc34vr500_chip_info,
 203                                                          NULL);
 204         if (IS_ERR(hwmon_dev))
 205                 return PTR_ERR(hwmon_dev);
 206
 207         data->hwmon_dev = hwmon_dev;
 208
 209         if (client->irq) {
 210                 ret = devm_request_threaded_irq(dev, client->irq, NULL,
 211                                                 mc34vr500_process_interrupt,
 212                                                 IRQF_TRIGGER_RISING |
 213                                                 IRQF_ONESHOT |
 214                                                 IRQF_SHARED,
 215                                                 dev_name(dev), data);
 216                 if (ret)
 217                         return ret;
 218
 219                 /* write 1 to clear interrupts */
 220                 ret = regmap_write(regmap, MC34VR500_INTSTAT0, LOWVINS_BIT |
 221                                    THERM110S_BIT | THERM120S_BIT |
 222                                    THERM130S_BIT);
 223                 if (ret)
 224                         return ret;
 225
 226                 /* unmask interrupts */
 227                 ret = regmap_write(regmap, MC34VR500_INTMASK0,
 228                                    (unsigned int) ~(LOWVINS_BIT | THERM110S_BIT |
 229                                                     THERM120S_BIT | THERM130S_BIT));
 230                 if (ret)
 231                         return ret;
 232         }
 233
 234         return 0;
 235 }
 236
 237 static const struct i2c_device_id mc34vr500_id[] = {
 238         { "mc34vr500", 0 },
 239         { },
 240 };
 241 MODULE_DEVICE_TABLE(i2c, mc34vr500_id);
 242
 243 static const struct of_device_id __maybe_unused mc34vr500_of_match[] = {
 244         { .compatible = "nxp,mc34vr500" },
 245         { },
 246 };
 247 MODULE_DEVICE_TABLE(of, mc34vr500_of_match);
 248
 249 static struct i2c_driver mc34vr500_driver = {
 250         .driver = {
 251                    .name = "mc34vr500",
 252                    .of_match_table = of_match_ptr(mc34vr500_of_match),
 253                     },
 254         .probe = mc34vr500_probe,
 255         .id_table = mc34vr500_id,
 256 };
 257
 258 module_i2c_driver(mc34vr500_driver);
 259
 260 MODULE_AUTHOR("Mario Kicherer <dev@kicherer.org>");
 261
 262 MODULE_DESCRIPTION("MC34VR500 driver");
 263 MODULE_LICENSE("GPL");