[PATCH v3 6/6] power: supply: max17040: Support soc alert
From: Iskren Chernev
Date: Wed Jun 24 2020 - 11:57:17 EST
max17048 and max17049 support SOC alerts (interrupts when battery
capacity changes by +/- 1%). At the moment the driver polls for changes
every second. Using the alerts removes the need for polling.
Signed-off-by: Iskren Chernev <iskren.chernev@xxxxxxxxx>
---
drivers/power/supply/max17040_battery.c | 82 ++++++++++++++++++++++---
1 file changed, 73 insertions(+), 9 deletions(-)
diff --git a/drivers/power/supply/max17040_battery.c b/drivers/power/supply/max17040_battery.c
index 54393f411211e..4425411775f26 100644
--- a/drivers/power/supply/max17040_battery.c
+++ b/drivers/power/supply/max17040_battery.c
@@ -25,6 +25,7 @@
#define MAX17040_MODE 0x06
#define MAX17040_VER 0x08
#define MAX17040_CONFIG 0x0C
+#define MAX17040_STATUS 0x1A
#define MAX17040_CMD 0xFE
@@ -33,7 +34,10 @@
#define MAX17040_RCOMP_DEFAULT 0x9700
#define MAX17040_ATHD_MASK 0x3f
+#define MAX17040_ALSC_MASK 0x40
#define MAX17040_ATHD_DEFAULT_POWER_UP 4
+#define MAX17040_STATUS_HD_MASK 0x1000
+#define MAX17040_STATUS_SC_MASK 0x2000
#define MAX17040_CFG_RCOMP_MASK 0xff00
enum chip_id {
@@ -55,6 +59,7 @@ struct chip_data {
u16 vcell_div;
u8 has_low_soc_alert;
u8 rcomp_bytes;
+ u8 has_soc_alert;
};
static struct chip_data max17040_family[] = {
@@ -65,6 +70,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 1,
.has_low_soc_alert = 0,
.rcomp_bytes = 2,
+ .has_soc_alert = 0,
},
[ID_MAX17041] = {
.reset_val = 0x0054,
@@ -73,6 +79,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 1,
.has_low_soc_alert = 0,
.rcomp_bytes = 2,
+ .has_soc_alert = 0,
},
[ID_MAX17043] = {
.reset_val = 0x0054,
@@ -81,6 +88,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 1,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 0,
},
[ID_MAX17044] = {
.reset_val = 0x0054,
@@ -89,6 +97,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 1,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 0,
},
[ID_MAX17048] = {
.reset_val = 0x5400,
@@ -97,6 +106,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 8,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 1,
},
[ID_MAX17049] = {
.reset_val = 0x5400,
@@ -105,6 +115,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 4,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 1,
},
[ID_MAX17058] = {
.reset_val = 0x5400,
@@ -113,6 +124,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 8,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 0,
},
[ID_MAX17059] = {
.reset_val = 0x5400,
@@ -121,6 +133,7 @@ static struct chip_data max17040_family[] = {
.vcell_div = 4,
.has_low_soc_alert = 1,
.rcomp_bytes = 1,
+ .has_soc_alert = 0,
},
};
@@ -156,6 +169,12 @@ static int max17040_set_low_soc_alert(struct max17040_chip *chip, u32 level)
MAX17040_ATHD_MASK, level);
}
+static int max17040_set_soc_alert(struct max17040_chip *chip, bool enable)
+{
+ return regmap_update_bits(chip->regmap, MAX17040_CONFIG,
+ MAX17040_ALSC_MASK, enable ? MAX17040_ALSC_MASK : 0);
+}
+
static int max17040_set_rcomp(struct max17040_chip *chip, u16 rcomp)
{
u16 mask = chip->data.rcomp_bytes == 2 ?
@@ -298,11 +317,33 @@ static void max17040_work(struct work_struct *work)
max17040_queue_work(chip);
}
+/* Returns true if alert cause was SOC change, not low SOC */
+static bool max17040_handle_soc_alert(struct max17040_chip *chip)
+{
+ bool ret = true;
+ u32 data;
+
+ regmap_read(chip->regmap, MAX17040_STATUS, &data);
+
+ if (data & MAX17040_STATUS_HD_MASK) {
+ // this alert was caused by low soc
+ ret = false;
+ }
+ if (data & MAX17040_STATUS_SC_MASK) {
+ // soc change bit -- deassert to mark as handled
+ regmap_write(chip->regmap, MAX17040_STATUS,
+ data & ~MAX17040_STATUS_SC_MASK);
+ }
+
+ return ret;
+}
+
static irqreturn_t max17040_thread_handler(int id, void *dev)
{
struct max17040_chip *chip = dev;
- dev_warn(&chip->client->dev, "IRQ: Alert battery low level");
+ if (!(chip->data.has_soc_alert && max17040_handle_soc_alert(chip)))
+ dev_warn(&chip->client->dev, "IRQ: Alert battery low level\n");
/* read registers */
max17040_check_changes(chip);
@@ -384,6 +425,7 @@ static int max17040_probe(struct i2c_client *client,
struct power_supply_config psy_cfg = {};
struct max17040_chip *chip;
enum chip_id chip_id;
+ bool enable_irq = false;
int ret;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
@@ -434,6 +476,27 @@ static int max17040_probe(struct i2c_client *client,
return ret;
}
+ enable_irq = true;
+ }
+
+ if (client->irq && chip->data.has_soc_alert) {
+ ret = max17040_set_soc_alert(chip, 1);
+ if (ret) {
+ dev_err(&client->dev,
+ "Failed to set SOC alert: err %d\n", ret);
+ return ret;
+ }
+ enable_irq = true;
+ } else {
+ /* soc alerts negate the need for polling */
+ INIT_DEFERRABLE_WORK(&chip->work, max17040_work);
+ ret = devm_add_action(&client->dev, max17040_stop_work, chip);
+ if (ret)
+ return ret;
+ max17040_queue_work(chip);
+ }
+
+ if (enable_irq) {
ret = max17040_enable_alert_irq(chip);
if (ret) {
client->irq = 0;
@@ -442,12 +505,6 @@ static int max17040_probe(struct i2c_client *client,
}
}
- INIT_DEFERRABLE_WORK(&chip->work, max17040_work);
- ret = devm_add_action(&client->dev, max17040_stop_work, chip);
- if (ret)
- return ret;
- max17040_queue_work(chip);
-
return 0;
}
@@ -458,7 +515,11 @@ static int max17040_suspend(struct device *dev)
struct i2c_client *client = to_i2c_client(dev);
struct max17040_chip *chip = i2c_get_clientdata(client);
- cancel_delayed_work(&chip->work);
+ if (client->irq && chip->data.has_soc_alert)
+ // disable soc alert to prevent wakeup
+ max17040_set_soc_alert(chip, 0);
+ else
+ cancel_delayed_work(&chip->work);
if (client->irq && device_may_wakeup(dev))
enable_irq_wake(client->irq);
@@ -474,7 +535,10 @@ static int max17040_resume(struct device *dev)
if (client->irq && device_may_wakeup(dev))
disable_irq_wake(client->irq);
- max17040_queue_work(chip);
+ if (client->irq && chip->data.has_soc_alert)
+ max17040_set_soc_alert(chip, 1);
+ else
+ max17040_queue_work(chip);
return 0;
}
--
2.27.0