On 3/16/22 16:41, Chris Packham wrote:
The adt7473, adt7475, adt7476 and adt7490 have pins that can be used for
different functions. On the adt7473 and adt7475 this is pins 5 and 9.
On the adt7476 and adt7490 this is pins 10 and 14.
The first pin can either be PWM2(default) or SMBALERT#. The second pin
can be TACH4(default), THERM#, SMBALERT# or GPIO.
The adt7475 driver has always been able to detect the configuration if
it had been done by an earlier boot stage. Add support for configuring
the pins based on the hardware description in the device tree.
Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
---
drivers/hwmon/adt7475.c | 95 +++++++++++++++++++++++++++++++++++++++++
1 file changed, 95 insertions(+)
diff --git a/drivers/hwmon/adt7475.c b/drivers/hwmon/adt7475.c
index 9d5b019651f2..ad5e5a7a844b 100644
--- a/drivers/hwmon/adt7475.c
+++ b/drivers/hwmon/adt7475.c
@@ -112,6 +112,8 @@
#define CONFIG3_THERM 0x02
#define CONFIG4_PINFUNC 0x03
+#define CONFIG4_THERM 0x01
+#define CONFIG4_SMBALERT 0x02
#define CONFIG4_MAXDUTY 0x08
#define CONFIG4_ATTN_IN10 0x30
#define CONFIG4_ATTN_IN43 0xC0
@@ -1460,6 +1462,95 @@ static int adt7475_update_limits(struct i2c_client *client)
return 0;
}
+static int load_pin10_config(const struct i2c_client *client, const char *propname)
+{
A better function name would probably be load_config3() or similar.
+ const char *function;
+ u8 config3;
+ int err;
+
+ err = of_property_read_string(client->dev.of_node, propname, &function);
+ if (!err) {
+ config3 = adt7475_read(REG_CONFIG3);
error check missing (I see the driver is notorious for that, but that is not
a reason to keep doing it).
+
+ if (!strcmp("pwm2", function))
+ config3 &= ~CONFIG3_SMBALERT;
+ else if (!strcmp("smbalert#", function))
+ config3 |= CONFIG3_SMBALERT;
+ else
+ return -EINVAL;
+
+ return i2c_smbus_write_byte_data(client, REG_CONFIG3, config3);
+ }
+
+ return 0;
+}
+
+static int load_pin14_config(const struct i2c_client *client, const char *propname)
+{
load_config4() ?
+ const char *function;
+ u8 config4;
+ int err;
+
+ err = of_property_read_string(client->dev.of_node, propname, &function);
+ if (!err) {
+ config4 = adt7475_read(REG_CONFIG4);
error check
+ config4 &= ~CONFIG4_PINFUNC;
+
+ if (!strcmp("tach4", function))
+ ;
+ else if (!strcmp("therm#", function))
+ config4 |= CONFIG4_THERM;
+ else if (!strcmp("smbalert#", function))
+ config4 |= CONFIG4_SMBALERT;
+ else if (!strcmp("gpio", function))
+ config4 |= CONFIG4_PINFUNC;
+ else
+ return -EINVAL;
+
+ return i2c_smbus_write_byte_data(client, REG_CONFIG4, config4);
+ }
+
+ return 0;
+}
+
+static int load_config(const struct i2c_client *client, int chip)
+{
+ int err;
+ const char *conf_prop1, *conf_prop2;
conf_ prefix is unnecessary.
+
+ switch (chip) {
+ case adt7473:
+ case adt7475:
+ conf_prop1 = "adi,pin5-function";
+ conf_prop2 = "adi,pin9-function";
+ break;
+ case adt7476:
+ case adt7490:
+ conf_prop1 = "adi,pin10-function";
+ conf_prop2 = "adi,pin14-function";
+ break;
+ default:
+ return -EINVAL;
It doesn't seem right to return -EINVAL here.
+ }
+
+ if (chip != adt7476 && chip != adt7490)
+ return 0;
+
Why not check this first, and what is the point of assigning values to
conf_prop1 and conf_prop2 for the other chips in the case statement above
only to return 0 here ? It would be much simpler to drop the other chips
from the case statement and have default: return 0.
+ err = load_pin10_config(client, conf_prop1);
+ if (err) {
+ dev_err(&client->dev, "failed to configure PIN10\n");
The messages are misleading. This isn't always pin 10/14.
+ return err;
+ }
+
+ err = load_pin14_config(client, conf_prop2);
+ if (err) {
+ dev_err(&client->dev, "failed to configure PIN14\n");
+ return err;
+ }
+
+ return 0;
+}
+
static int set_property_bit(const struct i2c_client *client, char *property,
u8 *config, u8 bit_index)
{
@@ -1585,6 +1676,10 @@ static int adt7475_probe(struct i2c_client *client)
revision = adt7475_read(REG_DEVID2) & 0x07;
}
+ ret = load_config(client, chip);
+ if (ret)
+ return ret;
+
config3 = adt7475_read(REG_CONFIG3);
/* Pin PWM2 may alternatively be used for ALERT output */
if (!(config3 & CONFIG3_SMBALERT))
