hwmon: (w83627ehf) Add support for suspend

On suspend some register values are lost, most notably the Value RAM
areas but also other limits and settings. Restore them on resume.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>

1 files changed, 94 insertions, 1 deletions

diff --git a/drivers/hwmon/w83627ehf.c b/drivers/hwmon/w83627ehf.c
index 55ac41c05561..7fbd0ba0f26f 100644
--- a/drivers/hwmon/w83627ehf.c
+++ b/drivers/hwmon/w83627ehf.c
@@ -1,7 +1,7 @@
 /*
  *  w83627ehf - Driver for the hardware monitoring functionality of
  *              the Winbond W83627EHF Super-I/O chip
- *  Copyright (C) 2005-2011  Jean Delvare <khali@linux-fr.org>
+ *  Copyright (C) 2005-2012  Jean Delvare <khali@linux-fr.org>
  *  Copyright (C) 2006  Yuan Mu (Winbond),
  *                      Rudolf Marek <r.marek@assembler.cz>
  *                      David Hubbard <david.c.hubbard@gmail.com>
@@ -502,6 +502,13 @@ struct w83627ehf_data {
         u16 have_temp_offset;
         u8 in6_skip:1;
         u8 temp3_val_only:1;
+
+#ifdef CONFIG_PM
+        /* Remember extra register values over suspend/resume */
+        u8 vbat;
+        u8 fandiv1;
+        u8 fandiv2;
+#endif
 };
 
 struct w83627ehf_sio_data {
@@ -2608,10 +2615,96 @@ static int w83627ehf_remove(struct platform_device *pdev)
         return 0;
 }
 
+#ifdef CONFIG_PM
+static int w83627ehf_suspend(struct device *dev)
+{
+        struct w83627ehf_data *data = w83627ehf_update_device(dev);
+        struct w83627ehf_sio_data *sio_data = dev->platform_data;
+
+        mutex_lock(&data->update_lock);
+        data->vbat = w83627ehf_read_value(data, W83627EHF_REG_VBAT);
+        if (sio_data->kind == nct6775) {
+                data->fandiv1 = w83627ehf_read_value(data, NCT6775_REG_FANDIV1);
+                data->fandiv2 = w83627ehf_read_value(data, NCT6775_REG_FANDIV2);
+        }
+        mutex_unlock(&data->update_lock);
+
+        return 0;
+}
+
+static int w83627ehf_resume(struct device *dev)
+{
+        struct w83627ehf_data *data = dev_get_drvdata(dev);
+        struct w83627ehf_sio_data *sio_data = dev->platform_data;
+        int i;
+
+        mutex_lock(&data->update_lock);
+        data->bank = 0xff;              /* Force initial bank selection */
+
+        /* Restore limits */
+        for (i = 0; i < data->in_num; i++) {
+                if ((i == 6) && data->in6_skip)
+                        continue;
+
+                w83627ehf_write_value(data, W83627EHF_REG_IN_MIN(i),
+                                      data->in_min[i]);
+                w83627ehf_write_value(data, W83627EHF_REG_IN_MAX(i),
+                                      data->in_max[i]);
+        }
+
+        for (i = 0; i < 5; i++) {
+                if (!(data->has_fan_min & (1 << i)))
+                        continue;
+
+                w83627ehf_write_value(data, data->REG_FAN_MIN[i],
+                                      data->fan_min[i]);
+        }
+
+        for (i = 0; i < NUM_REG_TEMP; i++) {
+                if (!(data->have_temp & (1 << i)))
+                        continue;
+
+                if (data->reg_temp_over[i])
+                        w83627ehf_write_temp(data, data->reg_temp_over[i],
+                                             data->temp_max[i]);
+                if (data->reg_temp_hyst[i])
+                        w83627ehf_write_temp(data, data->reg_temp_hyst[i],
+                                             data->temp_max_hyst[i]);
+                if (data->have_temp_offset & (1 << i))
+                        w83627ehf_write_value(data,
+                                              W83627EHF_REG_TEMP_OFFSET[i],
+                                              data->temp_offset[i]);
+        }
+
+        /* Restore other settings */
+        w83627ehf_write_value(data, W83627EHF_REG_VBAT, data->vbat);
+        if (sio_data->kind == nct6775) {
+                w83627ehf_write_value(data, NCT6775_REG_FANDIV1, data->fandiv1);
+                w83627ehf_write_value(data, NCT6775_REG_FANDIV2, data->fandiv2);
+        }
+
+        /* Force re-reading all values */
+        data->valid = 0;
+        mutex_unlock(&data->update_lock);
+
+        return 0;
+}
+
+static const struct dev_pm_ops w83627ehf_dev_pm_ops = {
+        .suspend = w83627ehf_suspend,
+        .resume = w83627ehf_resume,
+};
+
+#define W83627EHF_DEV_PM_OPS    (&w83627ehf_dev_pm_ops)
+#else
+#define W83627EHF_DEV_PM_OPS    NULL
+#endif /* CONFIG_PM */
+
 static struct platform_driver w83627ehf_driver = {
         .driver = {
                 .owner  = THIS_MODULE,
                 .name   = DRVNAME,
+                .pm     = W83627EHF_DEV_PM_OPS,
         },
         .probe          = w83627ehf_probe,
         .remove         = w83627ehf_remove,