On Thu, Mar 04, 2021 at 04:38:32PM +0100, Paul Menzel wrote: > From: Boyang Yu <byu@xxxxxxxxxx> > > We found that the max6658 sometimes issues a false alarm when its > convrate is changed, with the current hwmon driver. This workaround > will fix it by stopping the conversion before setting the convrate. > > Upstream the patch added added to the SONiC Linux kernel in merge/pull > request #82 [1][2]. > > [1]: https://github.com/Azure/sonic-linux-kernel/pull/82 > [2]: https://github.com/Azure/sonic-linux-kernel/commit/d03f6167f64b2bfa1330ff7b33fe217f68ab7028 > > [pmenzel: Forward port patch from 4.19 to 5.12-rc1+] > Signed-off-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx> > --- > drivers/hwmon/lm90.c | 15 ++++++++++++--- > 1 file changed, 12 insertions(+), 3 deletions(-) > > diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c > index ebbfd5f352c0..0c1a91b715e8 100644 > --- a/drivers/hwmon/lm90.c > +++ b/drivers/hwmon/lm90.c > @@ -639,7 +639,11 @@ static int lm90_set_convrate(struct i2c_client *client, struct lm90_data *data, > if (interval >= update_interval * 3 / 4) > break; > > - err = lm90_write_convrate(data, i); > + if (data->kind == max6657) > + err = max6657_write_convrate(client, i); There is no such function in the upstream kernel. Anyway, this problem has already been already fixed in the upstream kernel with commit 62456189f3292 ("hwmon: (lm90) Fix max6658 sporadic wrong temperature reading"). Guenter > + else > + err = lm90_write_convrate(data, i); > + > data->update_interval = DIV_ROUND_CLOSEST(update_interval, 64); > return err; > } > @@ -1649,7 +1653,11 @@ static void lm90_restore_conf(void *_data) > struct i2c_client *client = data->client; > > /* Restore initial configuration */ > - lm90_write_convrate(data, data->convrate_orig); > + if (data->kind == max6657) > + max6657_write_convrate(client, data->convrate_orig); > + else > + lm90_write_convrate(data, data->convrate_orig); > + > i2c_smbus_write_byte_data(client, LM90_REG_W_CONFIG1, > data->config_orig); > } > @@ -1672,7 +1680,8 @@ static int lm90_init_client(struct i2c_client *client, struct lm90_data *data) > data->config_orig = config; > data->config = config; > > - lm90_set_convrate(client, data, 500); /* 500ms; 2Hz conversion rate */ > + if (data->kind != max6657) > + lm90_set_convrate(client, data, 500); /* 500ms; 2Hz conversion rate */ > > /* Check Temperature Range Select */ > if (data->kind == adt7461 || data->kind == tmp451) {
