| Message ID | 20210513201110.313523-1-kubernat@cesnet.cz (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | hwmon: (pmbus/fsp-3y) Fix FSP-3Y YH-5151E VOUT | expand |
On Thu, May 13, 2021 at 10:11:10PM +0200, Václav Kubernát wrote: > After testing new YH-5151E devices, we found out that not all YH-5151E > work the same. The newly tested devices actually report vout correctly > in linear16 (even though they're still YH-5151E). We suspect that it is > because these new devices have a different firmware version, but that is > unconfirmed. The version cannot be queried through PMBus. > > The compliant versions of YH-5151E report VOUT_MODE normally, so we turn > on the linear11 workaround only if VOUT_MODE doesn't report anything. > What a mess. But thanks for keeping on top of this, and for the fix. Applied. Thanks, Guenter > Signed-off-by: Václav Kubernát <kubernat@cesnet.cz> > --- > drivers/hwmon/pmbus/fsp-3y.c | 32 +++++++++++++++++++++++++------- > 1 file changed, 25 insertions(+), 7 deletions(-) > > diff --git a/drivers/hwmon/pmbus/fsp-3y.c b/drivers/hwmon/pmbus/fsp-3y.c > index 46252b17c008..073d960a0af5 100644 > --- a/drivers/hwmon/pmbus/fsp-3y.c > +++ b/drivers/hwmon/pmbus/fsp-3y.c > @@ -37,6 +37,8 @@ struct fsp3y_data { > struct pmbus_driver_info info; > int chip; > int page; > + > + bool vout_linear_11; > }; > > #define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info) > @@ -108,11 +110,9 @@ static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg) > int rv; > > /* > - * YH5151-E outputs vout in linear11. The conversion is done when > - * reading. Here, we have to inject pmbus_core with the correct > - * exponent (it is -6). > + * Inject an exponent for non-compliant YH5151-E. > */ > - if (data->chip == yh5151e && reg == PMBUS_VOUT_MODE) > + if (data->vout_linear_11 && reg == PMBUS_VOUT_MODE) > return 0x1A; > > rv = set_page(client, page); > @@ -161,10 +161,9 @@ static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, > return rv; > > /* > - * YH-5151E is non-compliant and outputs output voltages in linear11 > - * instead of linear16. > + * Handle YH-5151E non-compliant linear11 vout voltage. > */ > - if (data->chip == yh5151e && reg == PMBUS_READ_VOUT) > + if (data->vout_linear_11 && reg == PMBUS_READ_VOUT) > rv = sign_extend32(rv, 10) & 0xffff; > > return rv; > @@ -256,6 +255,25 @@ static int fsp3y_probe(struct i2c_client *client) > > data->info = fsp3y_info[data->chip]; > > + /* > + * YH-5151E sometimes reports vout in linear11 and sometimes in > + * linear16. This depends on the exact individual piece of hardware. One > + * YH-5151E can use linear16 and another might use linear11 instead. > + * > + * The format can be recognized by reading VOUT_MODE - if it doesn't > + * report a valid exponent, then vout uses linear11. Otherwise, the > + * device is compliant and uses linear16. > + */ > + data->vout_linear_11 = false; > + if (data->chip == yh5151e) { > + rv = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE); > + if (rv < 0) > + return rv; > + > + if (rv == 0xFF) > + data->vout_linear_11 = true; > + } > + > return pmbus_do_probe(client, &data->info); > } >
diff --git a/drivers/hwmon/pmbus/fsp-3y.c b/drivers/hwmon/pmbus/fsp-3y.c index 46252b17c008..073d960a0af5 100644 --- a/drivers/hwmon/pmbus/fsp-3y.c +++ b/drivers/hwmon/pmbus/fsp-3y.c @@ -37,6 +37,8 @@ struct fsp3y_data { struct pmbus_driver_info info; int chip; int page; + + bool vout_linear_11; }; #define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info) @@ -108,11 +110,9 @@ static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg) int rv; /* - * YH5151-E outputs vout in linear11. The conversion is done when - * reading. Here, we have to inject pmbus_core with the correct - * exponent (it is -6). + * Inject an exponent for non-compliant YH5151-E. */ - if (data->chip == yh5151e && reg == PMBUS_VOUT_MODE) + if (data->vout_linear_11 && reg == PMBUS_VOUT_MODE) return 0x1A; rv = set_page(client, page); @@ -161,10 +161,9 @@ static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, return rv; /* - * YH-5151E is non-compliant and outputs output voltages in linear11 - * instead of linear16. + * Handle YH-5151E non-compliant linear11 vout voltage. */ - if (data->chip == yh5151e && reg == PMBUS_READ_VOUT) + if (data->vout_linear_11 && reg == PMBUS_READ_VOUT) rv = sign_extend32(rv, 10) & 0xffff; return rv; @@ -256,6 +255,25 @@ static int fsp3y_probe(struct i2c_client *client) data->info = fsp3y_info[data->chip]; + /* + * YH-5151E sometimes reports vout in linear11 and sometimes in + * linear16. This depends on the exact individual piece of hardware. One + * YH-5151E can use linear16 and another might use linear11 instead. + * + * The format can be recognized by reading VOUT_MODE - if it doesn't + * report a valid exponent, then vout uses linear11. Otherwise, the + * device is compliant and uses linear16. + */ + data->vout_linear_11 = false; + if (data->chip == yh5151e) { + rv = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE); + if (rv < 0) + return rv; + + if (rv == 0xFF) + data->vout_linear_11 = true; + } + return pmbus_do_probe(client, &data->info); }
After testing new YH-5151E devices, we found out that not all YH-5151E work the same. The newly tested devices actually report vout correctly in linear16 (even though they're still YH-5151E). We suspect that it is because these new devices have a different firmware version, but that is unconfirmed. The version cannot be queried through PMBus. The compliant versions of YH-5151E report VOUT_MODE normally, so we turn on the linear11 workaround only if VOUT_MODE doesn't report anything. Signed-off-by: Václav Kubernát <kubernat@cesnet.cz> --- drivers/hwmon/pmbus/fsp-3y.c | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-)