Merge tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply

Pull power supply and reset updates from Sebastian Reichel:
 "Power-supply core:
   - add COOL/WARM/HOT state from JEITA JISC8712:2015 specification
   - convert simple-battery DT binding to YAML
   - add long-life charging mode

 Battery/charger drivers:
   - bq25150: new charger driver
   - bq27xxx: add support for BQ27z561 and BQ28z610
   - max17040: support CAPACITY_ALERT_MIN
   - sbs-battery: add PEC support
   - wilco-ec: support long-life charging mode
   - bq25890: fix DT binding
   - misc. fixes and cleanups

 Reset drivers:
   - linkstation: new reset driver"

* tag 'for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (32 commits)
  power: supply: wilco_ec: Add long life charging mode
  power: supply: bq27xxx_battery: Add the BQ28z610 Battery monitor
  dt-bindings: power: Add BQ28z610 compatible
  power: supply: bq27xxx_battery: Add the BQ27Z561 Battery monitor
  dt-bindings: power: Add BQ27Z561 compatible
  power: supply: test_power: Fix battery_current initial value
  power: supply: Fix kerneldoc of power_supply_temp2resist_simple()
  power: supply: cpcap-battery: Fix kerneldoc of cpcap_battery_read_accumulated()
  dt-bindings: power: Convert battery.txt to battery.yaml
  power: supply: rt5033_battery: Fix error code in rt5033_battery_probe()
  power: supply: max17040: Add POWER_SUPPLY_PROP_CAPACITY_ALERT_MIN
  power: supply: check if calc_soc succeeded in pm860x_init_battery
  power: supply: bq2xxxx: Replace HTTP links with HTTPS ones
  power: reset: add driver for LinkStation power off
  power: supply: sc27xx: prevent adc * 1000 from overflow
  math64: New DIV_S64_ROUND_CLOSEST helper
  power: fix duplicated words in bq2415x_charger.h
  power: Convert to DEFINE_SHOW_ATTRIBUTE
  power: reset: keystone-reset: Replace HTTP links with HTTPS ones
  power: supply: bq25150 introduce the bq25150
  ...

1 files changed, 87 insertions, 2 deletions

diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
index 83b9924033bd..49c3508a6b79 100644
--- a/drivers/power/supply/sbs-battery.c
+++ b/drivers/power/supply/sbs-battery.c
@@ -51,6 +51,14 @@ enum {
 	REG_CHARGE_VOLTAGE,
 };
 
+#define REG_ADDR_SPEC_INFO		0x1A
+#define SPEC_INFO_VERSION_MASK		GENMASK(7, 4)
+#define SPEC_INFO_VERSION_SHIFT		4
+
+#define SBS_VERSION_1_0			1
+#define SBS_VERSION_1_1			2
+#define SBS_VERSION_1_1_WITH_PEC	3
+
 #define REG_ADDR_MANUFACTURE_DATE	0x1B
 
 /* Battery Mode defines */
@@ -224,14 +232,57 @@ exit:
 
 static int sbs_update_presence(struct sbs_info *chip, bool is_present)
 {
+	struct i2c_client *client = chip->client;
+	int retries = chip->i2c_retry_count;
+	s32 ret = 0;
+	u8 version;
+
 	if (chip->is_present == is_present)
 		return 0;
 
 	if (!is_present) {
 		chip->is_present = false;
+		/* Disable PEC when no device is present */
+		client->flags &= ~I2C_CLIENT_PEC;
 		return 0;
 	}
 
+	/* Check if device supports packet error checking and use it */
+	while (retries > 0) {
+		ret = i2c_smbus_read_word_data(client, REG_ADDR_SPEC_INFO);
+		if (ret >= 0)
+			break;
+
+		/*
+		 * Some batteries trigger the detection pin before the
+		 * I2C bus is properly connected. This works around the
+		 * issue.
+		 */
+		msleep(100);
+
+		retries--;
+	}
+
+	if (ret < 0) {
+		dev_dbg(&client->dev, "failed to read spec info: %d\n", ret);
+
+		/* fallback to old behaviour */
+		client->flags &= ~I2C_CLIENT_PEC;
+		chip->is_present = true;
+
+		return ret;
+	}
+
+	version = (ret & SPEC_INFO_VERSION_MASK) >> SPEC_INFO_VERSION_SHIFT;
+
+	if (version == SBS_VERSION_1_1_WITH_PEC)
+		client->flags |= I2C_CLIENT_PEC;
+	else
+		client->flags &= ~I2C_CLIENT_PEC;
+
+	dev_dbg(&client->dev, "PEC: %s\n", (client->flags & I2C_CLIENT_PEC) ?
+		"enabled" : "disabled");
+
 	if (!chip->is_present && is_present && !chip->charger_broadcasts)
 		sbs_disable_charger_broadcasts(chip);
 
@@ -263,8 +314,7 @@ static int sbs_read_word_data(struct i2c_client *client, u8 address)
 	return ret;
 }
 
-static int sbs_read_string_data(struct i2c_client *client, u8 address,
-				char *values)
+static int sbs_read_string_data_fallback(struct i2c_client *client, u8 address, char *values)
 {
 	struct sbs_info *chip = i2c_get_clientdata(client);
 	s32 ret = 0, block_length = 0;
@@ -274,6 +324,9 @@ static int sbs_read_string_data(struct i2c_client *client, u8 address,
 	retries_length = chip->i2c_retry_count;
 	retries_block = chip->i2c_retry_count;
 
+	dev_warn_once(&client->dev, "I2C adapter does not support I2C_FUNC_SMBUS_READ_BLOCK_DATA.\n"
+				    "Fallback method does not support PEC.\n");
+
 	/* Adapter needs to support these two functions */
 	if (!i2c_check_functionality(client->adapter,
 				     I2C_FUNC_SMBUS_BYTE_DATA |
@@ -329,6 +382,38 @@ static int sbs_read_string_data(struct i2c_client *client, u8 address,
 	return ret;
 }
 
+static int sbs_read_string_data(struct i2c_client *client, u8 address, char *values)
+{
+	struct sbs_info *chip = i2c_get_clientdata(client);
+	int retries = chip->i2c_retry_count;
+	int ret = 0;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BLOCK_DATA)) {
+		bool pec = client->flags & I2C_CLIENT_PEC;
+		client->flags &= ~I2C_CLIENT_PEC;
+		ret = sbs_read_string_data_fallback(client, address, values);
+		if (pec)
+			client->flags |= I2C_CLIENT_PEC;
+		return ret;
+	}
+
+	while (retries > 0) {
+		ret = i2c_smbus_read_block_data(client, address, values);
+		if (ret >= 0)
+			break;
+		retries--;
+	}
+
+	if (ret < 0) {
+		dev_dbg(&client->dev, "failed to read block 0x%x: %d\n", address, ret);
+		return ret;
+	}
+
+	/* add string termination */
+	values[ret] = '\0';
+	return ret;
+}
+
 static int sbs_write_word_data(struct i2c_client *client, u8 address,
 	u16 value)
 {