Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-01 10:43:43 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

hwmon: (ina2xx) Add device tree support to pass alert polarity

Browse Source 
The INA230 has an Alert pin which is asserted when the alert
function selected in the Mask/Enable register exceeds the
value programmed into the Alert Limit register. Assertion is based
on the Alert Polarity Bit (APOL, bit 1 of the Mask/Enable register).
It is default set to value 0 i.e Normal (active-low open collector).
However, hardware can be designed in such a way that expects Alert pin
to become active high if a user-defined threshold in Alert limit
register has been exceeded. This patch adds a way to pass alert polarity
value to the driver via device tree.

Signed-off-by: Amna Waseem <Amna.Waseem@axis.com>
Link: https://lore.kernel.org/r/20240611-apol-ina2xx-fix-v4-2-8df1d2282fc5@axis.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Amna Waseem 2024-06-11 11:36:26 +02:00 committed by Guenter Roeck
parent 94e33109f9
commit ec5d234f19
1 changed files with 32 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

32
drivers/hwmon/ina2xx.c
View File

@ -73,6 +73,11 @@
#define INA226_READ_AVG(reg) (((reg) & INA226_AVG_RD_MASK) >> 9)
#define INA226_SHIFT_AVG(val) ((val) << 9)
#define INA226_ALERT_POLARITY_MASK 0x0002
#define INA226_SHIFT_ALERT_POLARITY(val) ((val) << 1)
#define INA226_ALERT_POL_LOW 0
#define INA226_ALERT_POL_HIGH 1
/* bit number of alert functions in Mask/Enable Register */
#define INA226_SHUNT_OVER_VOLTAGE_BIT 15
#define INA226_SHUNT_UNDER_VOLTAGE_BIT 14
@ -178,6 +183,14 @@ static u16 ina226_interval_to_reg(int interval)
return INA226_SHIFT_AVG(avg_bits);
}
static int ina2xx_set_alert_polarity(struct ina2xx_data *data,
unsigned long val)
{
return regmap_update_bits(data->regmap, INA226_MASK_ENABLE,
INA226_ALERT_POLARITY_MASK,
INA226_SHIFT_ALERT_POLARITY(val));
}
/*
* Calibration register is set to the best value, which eliminates
* truncation errors on calculating current register in hardware.
@ -654,6 +667,25 @@ static int ina2xx_probe(struct i2c_client *client)
if (ret)
return dev_err_probe(dev, ret, "failed to enable vs regulator\n");
if (chip == ina226) {
if (of_property_read_bool(dev->of_node, "ti,alert-polarity-active-high")) {
ret = ina2xx_set_alert_polarity(data,
INA226_ALERT_POL_HIGH);
if (ret < 0) {
return dev_err_probe(dev, ret,
"failed to set alert polarity active high\n");
}
} else {
/* Set default value i.e active low */
ret = ina2xx_set_alert_polarity(data,
INA226_ALERT_POL_LOW);
if (ret < 0) {
return dev_err_probe(dev, ret,
"failed to set alert polarity active low\n");
}
}
}
ret = ina2xx_init(data);
if (ret < 0) {
dev_err(dev, "error configuring the device: %d\n", ret);