Hi,
On 1/6/24 09:05, Guenter Roeck wrote:
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@xxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
v3: No change
v2: New patch
RFT: I tested the patch through a suspend/resume cycle, and it seems
to work, but I am not sure if that had any effect because,
after all, the memory is still active during suspend/resume.
I was unable to test a hibernation cycle with my system.
For me, the driver just reports 0°C after suspend/resume, but works fine
beforehand, tested on both my desktop and laptop, with kernel 6.9.3 and
6.10.0-rc2 (on the laptop only).
Hibernation does seem to work fine though (at least on 6.9.3).
drivers/hwmon/spd5118.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)
diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c
index d3fc0ae17743..baa315172298 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 +452,31 @@ static int spd5118_probe(struct i2c_client *client)
return 0;
}
+static int spd5118_suspend(struct device *dev)
+{
+ struct regmap *regmap = dev_get_drvdata(dev);
+
+ 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);
Adding something like this fixes the readings after resume for me:
regmap_update_bits(regmap, SPD5118_REG_TEMP_CONFIG, SPD5118_TS_DISABLE, 0);
But that was just the naive solution I thought of.
+ 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 +494,7 @@ 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,
For reference: I believe both my devices also have Montage Technology
M88SPD5118 chips; the desktop has Kingston KF560C36-32 RAM, the laptop
has Crucial CT16G56C46S5.
Thanks,
Steve
