Add suspend/resume support to ensure that limit and configuration
registers are updated and synchronized after a suspend/resume cycle.

Cc: Armin Wolf <W_Armin@gmx.de>
Cc: Stephen Horvath <s.horvath@outlook.com.au>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
v4: Fix bug seen if the enable attribute was never read prior
    to a suspend/resume cycle.

v3: No change

v2: New patch

 drivers/hwmon/spd5118.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c
index d3fc0ae17743..d55c073ff5fd 100644
--- a/drivers/hwmon/spd5118.c
+++ b/drivers/hwmon/spd5118.c
@@ -20,6 +20,7 @@
 #include <linux/i2c.h>
 #include <linux/hwmon.h>
 #include <linux/module.h>
+#include <linux/pm.h>
 #include <linux/regmap.h>
 #include <linux/units.h>
 
@@ -432,6 +433,8 @@ static int spd5118_probe(struct i2c_client *client)
 	if (!spd5118_vendor_valid(bank, vendor))
 		return -ENODEV;
 
+	dev_set_drvdata(dev, regmap);
+
 	hwmon_dev = devm_hwmon_device_register_with_info(dev, "spd5118",
 							 regmap, &spd5118_chip_info,
 							 NULL);
@@ -449,6 +452,41 @@ static int spd5118_probe(struct i2c_client *client)
 	return 0;
 }
 
+static int spd5118_suspend(struct device *dev)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+	u32 regval;
+	int err;
+
+	/*
+	 * Make sure the configuration register in the regmap cache is current
+	 * before bypassing it.
+	 */
+	err = regmap_read(regmap, SPD5118_REG_TEMP_CONFIG, &regval);
+	if (err < 0)
+		return err;
+
+	regcache_cache_bypass(regmap, true);
+	regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG, SPD5118_TS_DISABLE,
+			   SPD5118_TS_DISABLE);
+	regcache_cache_bypass(regmap, false);
+
+	regcache_cache_only(regmap, true);
+	regcache_mark_dirty(regmap);
+
+	return 0;
+}
+
+static int spd5118_resume(struct device *dev)
+{
+	struct regmap *regmap = dev_get_drvdata(dev);
+
+	regcache_cache_only(regmap, false);
+	return regcache_sync(regmap);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(spd5118_pm_ops, spd5118_suspend, spd5118_resume);
+
 static const struct i2c_device_id spd5118_id[] = {
 	{ "spd5118", 0 },
 	{ }
@@ -466,6 +504,7 @@ static struct i2c_driver spd5118_driver = {
 	.driver = {
 		.name	= "spd5118",
 		.of_match_table = spd5118_of_ids,
+		.pm = pm_sleep_ptr(&spd5118_pm_ops),
 	},
 	.probe		= spd5118_probe,
 	.id_table	= spd5118_id,
-- 
2.39.2

Am 04.06.24 um 06:02 schrieb Guenter Roeck:

> Add suspend/resume support to ensure that limit and configuration
> registers are updated and synchronized after a suspend/resume cycle.

Tested-by: Armin Wolf <W_Armin@gmx.de>

>
> Cc: Armin Wolf <W_Armin@gmx.de>
> Cc: Stephen Horvath <s.horvath@outlook.com.au>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> v4: Fix bug seen if the enable attribute was never read prior
>      to a suspend/resume cycle.
>
> v3: No change
>
> v2: New patch
>
>   drivers/hwmon/spd5118.c | 39 +++++++++++++++++++++++++++++++++++++++
>   1 file changed, 39 insertions(+)
>
> diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c
> index d3fc0ae17743..d55c073ff5fd 100644
> --- a/drivers/hwmon/spd5118.c
> +++ b/drivers/hwmon/spd5118.c
> @@ -20,6 +20,7 @@
>   #include <linux/i2c.h>
>   #include <linux/hwmon.h>
>   #include <linux/module.h>
> +#include <linux/pm.h>
>   #include <linux/regmap.h>
>   #include <linux/units.h>
>
> @@ -432,6 +433,8 @@ static int spd5118_probe(struct i2c_client *client)
>   	if (!spd5118_vendor_valid(bank, vendor))
>   		return -ENODEV;
>
> +	dev_set_drvdata(dev, regmap);
> +
>   	hwmon_dev = devm_hwmon_device_register_with_info(dev, "spd5118",
>   							 regmap, &spd5118_chip_info,
>   							 NULL);
> @@ -449,6 +452,41 @@ static int spd5118_probe(struct i2c_client *client)
>   	return 0;
>   }
>
> +static int spd5118_suspend(struct device *dev)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +	u32 regval;
> +	int err;
> +
> +	/*
> +	 * Make sure the configuration register in the regmap cache is current
> +	 * before bypassing it.
> +	 */
> +	err = regmap_read(regmap, SPD5118_REG_TEMP_CONFIG, &regval);
> +	if (err < 0)
> +		return err;
> +
> +	regcache_cache_bypass(regmap, true);
> +	regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG, SPD5118_TS_DISABLE,
> +			   SPD5118_TS_DISABLE);
> +	regcache_cache_bypass(regmap, false);
> +
> +	regcache_cache_only(regmap, true);
> +	regcache_mark_dirty(regmap);
> +
> +	return 0;
> +}
> +
> +static int spd5118_resume(struct device *dev)
> +{
> +	struct regmap *regmap = dev_get_drvdata(dev);
> +
> +	regcache_cache_only(regmap, false);
> +	return regcache_sync(regmap);
> +}
> +
> +static DEFINE_SIMPLE_DEV_PM_OPS(spd5118_pm_ops, spd5118_suspend, spd5118_resume);
> +
>   static const struct i2c_device_id spd5118_id[] = {
>   	{ "spd5118", 0 },
>   	{ }
> @@ -466,6 +504,7 @@ static struct i2c_driver spd5118_driver = {
>   	.driver = {
>   		.name	= "spd5118",
>   		.of_match_table = spd5118_of_ids,
> +		.pm = pm_sleep_ptr(&spd5118_pm_ops),
>   	},
>   	.probe		= spd5118_probe,
>   	.id_table	= spd5118_id,