diff options
author | Fabio Baltieri <fabio.baltieri@gmail.com> | 2014-06-08 22:06:24 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-07-09 11:18:26 -0700 |
commit | 15a446b98f735f427927a251e82fed0a5a59c9ee (patch) | |
tree | 4afe42a8f27da84194ed3ac19632bd4b3b5b4120 | |
parent | caa1bc98057da9435a67aa6e508469b4b0238615 (diff) |
hwmon: (ina2xx) Cast to s16 on shunt and current regs
commit c0214f98943b1fe43f7be61b7782b0c8f0836f28 upstream.
All devices supported by ina2xx are bidirectional and report the
measured shunt voltage and power values as a signed 16 bit, but the
current driver implementation caches all registers as u16, leading
to an incorrect sign extension when reporting to userspace in
ina2xx_get_value().
This patch fixes the problem by casting the signed registers to s16.
Tested on an INA219.
Signed-off-by: Fabio Baltieri <fabio.baltieri@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/hwmon/ina2xx.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c index 93d26e8af3e2..bfd3f3eeabcd 100644 --- a/drivers/hwmon/ina2xx.c +++ b/drivers/hwmon/ina2xx.c @@ -148,7 +148,8 @@ static int ina2xx_get_value(struct ina2xx_data *data, u8 reg) switch (reg) { case INA2XX_SHUNT_VOLTAGE: - val = DIV_ROUND_CLOSEST(data->regs[reg], + /* signed register */ + val = DIV_ROUND_CLOSEST((s16)data->regs[reg], data->config->shunt_div); break; case INA2XX_BUS_VOLTAGE: @@ -160,8 +161,8 @@ static int ina2xx_get_value(struct ina2xx_data *data, u8 reg) val = data->regs[reg] * data->config->power_lsb; break; case INA2XX_CURRENT: - /* LSB=1mA (selected). Is in mA */ - val = data->regs[reg]; + /* signed register, LSB=1mA (selected), in mA */ + val = (s16)data->regs[reg]; break; default: /* programmer goofed */ |