hwmon: (max6697) Add support for tempX_min and tempX_min_alarm

MAX6581 supports setting the minimum temperature as well as minimum
temperature alarms. Add support for it.

Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/max6697.c b/drivers/hwmon/max6697.c
index bfbaf1b64c1eee1e834dfb25ea7375a8293c6aa2..0c34c0c812321a4aa65538e63a94bc8906b19e6f 100644 (file)
--- a/drivers/hwmon/max6697.c
+++ b/drivers/hwmon/max6697.c
@@ -32,6 +32,7 @@ static const u8 MAX6697_REG_MAX[] = {
 static const u8 MAX6697_REG_CRIT[] = {
                        0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27 };
 
+#define MAX6697_REG_MIN                        0x30
 /*
  * Map device tree / internal register bit map to chip bit map.
  * Applies to alert register and over-temperature register.
@@ -54,6 +55,7 @@ static const u8 MAX6697_REG_CRIT[] = {
 #define MAX6697_REG_STAT_ALARM         0x44
 #define MAX6697_REG_STAT_CRIT          0x45
 #define MAX6697_REG_STAT_FAULT         0x46
+#define MAX6697_REG_STAT_MIN_ALARM     0x47
 
 #define MAX6697_REG_CONFIG             0x41
 #define MAX6581_CONF_EXTENDED          BIT(1)
@@ -173,6 +175,18 @@ static const struct max6697_chip_data max6697_chip_data[] = {
        },
 };
 
+static int max6697_alarm_channel_map(int channel)
+{
+       switch (channel) {
+       case 0:
+               return 6;
+       case 7:
+               return 7;
+       default:
+               return channel - 1;
+       }
+}
+
 static int max6697_read(struct device *dev, enum hwmon_sensor_types type,
                        u32 attr, int channel, long *val)
 {
@@ -205,6 +219,12 @@ static int max6697_read(struct device *dev, enum hwmon_sensor_types type,
                        return ret;
                *val = ((int)regval - data->temp_offset) * 1000;
                break;
+       case hwmon_temp_min:
+               ret = regmap_read(regmap, MAX6697_REG_MIN, &regval);
+               if (ret)
+                       return ret;
+               *val = ((int)regval - data->temp_offset) * 1000;
+               break;
        case hwmon_temp_offset:
                ret = regmap_multi_reg_read(regmap, offset_regs, regdata, 2);
                if (ret)
@@ -234,17 +254,13 @@ static int max6697_read(struct device *dev, enum hwmon_sensor_types type,
                ret = regmap_read(regmap, MAX6697_REG_STAT_ALARM, &regval);
                if (ret)
                        return ret;
-               switch (channel) {
-               case 0:
-                       *val = !!(regval & BIT(6));
-                       break;
-               case 7:
-                       *val = !!(regval & BIT(7));
-                       break;
-               default:
-                       *val = !!(regval & BIT(channel - 1));
-                       break;
-               }
+               *val = !!(regval & BIT(max6697_alarm_channel_map(channel)));
+               break;
+       case hwmon_temp_min_alarm:
+               ret = regmap_read(regmap, MAX6697_REG_STAT_MIN_ALARM, &regval);
+               if (ret)
+                       return ret;
+               *val = !!(regval & BIT(max6697_alarm_channel_map(channel)));
                break;
        default:
                return -EOPNOTSUPP;
@@ -270,6 +286,11 @@ static int max6697_write(struct device *dev, enum hwmon_sensor_types type,
                val = DIV_ROUND_CLOSEST(val, 1000) + data->temp_offset;
                val = clamp_val(val, 0, data->type == max6581 ? 255 : 127);
                return regmap_write(regmap, MAX6697_REG_CRIT[channel], val);
+       case hwmon_temp_min:
+               val = clamp_val(val, -1000000, 1000000);        /* prevent underflow */
+               val = DIV_ROUND_CLOSEST(val, 1000) + data->temp_offset;
+               val = clamp_val(val, 0, 255);
+               return regmap_write(regmap, MAX6697_REG_MIN, val);
        case hwmon_temp_offset:
                mutex_lock(&data->update_lock);
                val = clamp_val(val, MAX6581_OFFSET_MIN, MAX6581_OFFSET_MAX);
@@ -308,6 +329,14 @@ static umode_t max6697_is_visible(const void *_data, enum hwmon_sensor_types typ
        case hwmon_temp_input:
        case hwmon_temp_max_alarm:
                return 0444;
+       case hwmon_temp_min:
+               if (data->type == max6581)
+                       return channel ? 0444 : 0644;
+               break;
+       case hwmon_temp_min_alarm:
+               if (data->type == max6581)
+                       return 0444;
+               break;
        case hwmon_temp_crit:
                if (chip->have_crit & BIT(channel))
                        return 0644;
@@ -334,27 +363,35 @@ static umode_t max6697_is_visible(const void *_data, enum hwmon_sensor_types typ
 static const struct hwmon_channel_info * const max6697_info[] = {
        HWMON_CHANNEL_INFO(temp,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET,
                           HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT |
                           HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM |
+                          HWMON_T_MIN | HWMON_T_MIN_ALARM |
                           HWMON_T_FAULT | HWMON_T_OFFSET),
        NULL
 };