Skip to content

Commit

Permalink
hwmon: (tps23861) fix byte order in resistance register
Browse files Browse the repository at this point in the history
commit 1f05f65 upstream.

The tps23861 registers are little-endian, and regmap_read_bulk() does
not do byte order conversion. On BE machines, the bytes were swapped,
and the interpretation of the resistance value was incorrect.

To make it work on both big and little-endian machines, use
le16_to_cpu() to convert the resitance register to host byte order.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Fixes: fff7b8a ("hwmon: add Texas Instruments TPS23861 driver")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220905142806.110598-1-mr.nuke.me@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  • Loading branch information
mrnuke authored and gregkh committed Sep 15, 2022
1 parent 0f9f9c7 commit f3cf916
Showing 1 changed file with 6 additions and 4 deletions.
10 changes: 6 additions & 4 deletions drivers/hwmon/tps23861.c
Expand Up @@ -489,18 +489,20 @@ static char *tps23861_port_poe_plus_status(struct tps23861_data *data, int port)

static int tps23861_port_resistance(struct tps23861_data *data, int port)
{
u16 regval;
unsigned int raw_val;
__le16 regval;

regmap_bulk_read(data->regmap,
PORT_1_RESISTANCE_LSB + PORT_N_RESISTANCE_LSB_OFFSET * (port - 1),
&regval,
2);

switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, regval)) {
raw_val = le16_to_cpu(regval);
switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, raw_val)) {
case PORT_RESISTANCE_RSN_OTHER:
return (FIELD_GET(PORT_RESISTANCE_MASK, regval) * RESISTANCE_LSB) / 10000;
return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB) / 10000;
case PORT_RESISTANCE_RSN_LOW:
return (FIELD_GET(PORT_RESISTANCE_MASK, regval) * RESISTANCE_LSB_LOW) / 10000;
return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB_LOW) / 10000;
case PORT_RESISTANCE_RSN_SHORT:
case PORT_RESISTANCE_RSN_OPEN:
default:
Expand Down

0 comments on commit f3cf916

Please sign in to comment.