hwmon: (lm75) Add STLM75 support

The STLM75 is a high-precision digital CMOS temperature sensor
IC with a sigma-delta temperature-to-digital converter.

The configuration register mapping is similar to existing lm75
but the sample rate is 150ms(max).

Tested on real hardware and verified temperature readings are correct.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/lm75.c

@@ -50,6 +50,7 @@ enum lm75_type {		/* keep sorted in alphabetical order */
 	max31725,
 	mcp980x,
 	stds75,
+	stlm75,
 	tcn75,
 	tmp100,
 	tmp101,
@@ -316,6 +317,10 @@ lm75_probe(struct i2c_client *client, const struct i2c_device_id *id)
 		data->resolution = 11;
 		data->sample_time = MSEC_PER_SEC;
 		break;
+	case stlm75:
+		data->resolution = 9;
+		data->sample_time = MSEC_PER_SEC / 5;
+		break;
 	case ds7505:
 		set_mask |= 3 << 5;		/* 12-bit mode */
 		data->resolution = 12;
@@ -424,6 +429,7 @@ static const struct i2c_device_id lm75_ids[] = {
 	{ "max31726", max31725, },
 	{ "mcp980x", mcp980x, },
 	{ "stds75", stds75, },
+	{ "stlm75", stlm75, },
 	{ "tcn75", tcn75, },
 	{ "tmp100", tmp100, },
 	{ "tmp101", tmp101, },
@@ -494,6 +500,10 @@ static const struct of_device_id lm75_of_match[] = {
 		.compatible = "st,stds75",
 		.data = (void *)stds75
 	},
+	{
+		.compatible = "st,stlm75",
+		.data = (void *)stlm75
+	},
 	{
 		.compatible = "microchip,tcn75",
 		.data = (void *)tcn75