hwmon: (ntc_thermistor) Drop get_ohm()

Nothing in the kernel (this driver) is using the callback to
read ohms directly. We always read a voltage and convert it
to a resistance. Drop this callback.

Cc: Peter Rosin <peda@axentia.se>
Cc: Chris Lesiak <chris.lesiak@licor.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20211125020841.3616359-3-linus.walleij@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/ntc_thermistor.c b/drivers/hwmon/ntc_thermistor.c
index 034ef55d0706d110b3cb96e8f46555669c52dfd3..8a78e899fa12bd45417a695d6c30bd07518d7be0 100644 (file)
--- a/drivers/hwmon/ntc_thermistor.c
+++ b/drivers/hwmon/ntc_thermistor.c
@@ -28,10 +28,6 @@ enum ntc_thermistor_type {
 
 struct ntc_thermistor_platform_data {
        /*
-        * One (not both) of read_uV and read_ohm should be provided and only
-        * one of the two should be provided.
-        * Both functions should return negative value for an error case.
-        *
         * pullup_uV, pullup_ohm, pulldown_ohm, and connect are required to use
         * read_uV()
         *
@@ -50,8 +46,6 @@ struct ntc_thermistor_platform_data {
        unsigned int pulldown_ohm;
        enum { NTC_CONNECTED_POSITIVE, NTC_CONNECTED_GROUND } connect;
        struct iio_channel *chan;
-
-       int (*read_ohm)(void);
 };
 
 struct ntc_compensation {
@@ -600,9 +594,6 @@ static int ntc_thermistor_get_ohm(struct ntc_data *data)
 {
        int read_uv;
 
-       if (data->pdata->read_ohm)
-               return data->pdata->read_ohm();
-
        if (data->pdata->read_uv) {
                read_uv = data->pdata->read_uv(data->pdata);
                if (read_uv < 0)
@@ -690,19 +681,11 @@ static int ntc_thermistor_probe(struct platform_device *pdev)
                return -ENODEV;
        }
 
-       /* Either one of the two is required. */
-       if (!pdata->read_uv && !pdata->read_ohm) {
-               dev_err(dev,
-                       "Both read_uv and read_ohm missing. Need either one of the two.\n");
+       if (!pdata->read_uv) {
+               dev_err(dev, "read_uv missing\n");
                return -EINVAL;
        }
 
-       if (pdata->read_uv && pdata->read_ohm) {
-               dev_warn(dev,
-                        "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
-               pdata->read_uv = NULL;
-       }
-
        if (pdata->read_uv && (pdata->pullup_uv == 0 ||
                                (pdata->pullup_ohm == 0 && pdata->connect ==
                                 NTC_CONNECTED_GROUND) ||