| Message ID | 20210701152825.265729-1-jglisse@redhat.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | misc: eeprom: at24: Always append device id even if label property is set. | expand |
On Thu, Jul 1, 2021 at 5:28 PM <jglisse@redhat.com> wrote: > > From: Jérôme Glisse <jglisse@redhat.com> > > We need to append device id even if eeprom have a label property set as some > platform can have multiple eeproms with same label and we can not register > each of those with same label. Failing to register those eeproms trigger > cascade failures on such platform (system is no longer working). > > This fix regression on such platform introduced with 4e302c3b568e > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > Cc: Diego Santa Cruz <Diego.SantaCruz@spinetix.com> > Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> > Cc: Jon Hunter <jonathanh@nvidia.com> > Cc: stable@vger.kernel.org > Cc: linux-i2c@vger.kernel.org > --- > drivers/misc/eeprom/at24.c | 17 +++++++---------- > 1 file changed, 7 insertions(+), 10 deletions(-) > > diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c > index 7a6f01ace78a..305ffad131a2 100644 > --- a/drivers/misc/eeprom/at24.c > +++ b/drivers/misc/eeprom/at24.c > @@ -714,23 +714,20 @@ static int at24_probe(struct i2c_client *client) > } > > /* > - * If the 'label' property is not present for the AT24 EEPROM, > - * then nvmem_config.id is initialised to NVMEM_DEVID_AUTO, > - * and this will append the 'devid' to the name of the NVMEM > - * device. This is purely legacy and the AT24 driver has always > - * defaulted to this. However, if the 'label' property is > - * present then this means that the name is specified by the > - * firmware and this name should be used verbatim and so it is > - * not necessary to append the 'devid'. > + * We initialize nvmem_config.id to NVMEM_DEVID_AUTO even if the > + * label property is set as some platform can have multiple eeproms > + * with same label and we can not register each of those with same > + * label. Failing to register those eeproms trigger cascade failure > + * on such platform. > */ > + nvmem_config.id = NVMEM_DEVID_AUTO; > + > if (device_property_present(dev, "label")) { > - nvmem_config.id = NVMEM_DEVID_NONE; > err = device_property_read_string(dev, "label", > &nvmem_config.name); > if (err) > return err; > } else { > - nvmem_config.id = NVMEM_DEVID_AUTO; > nvmem_config.name = dev_name(dev); > } > > -- > 2.31.1 > Cc'ing Alexander Fomichev who reported this issue first. This is the second time someone raises this problem so it seems that this change really broke many existing systems. I will apply this patch and send it for stable. Bart
The proposed patch has been tested and it solves the problem. Thanks. Tested-by: Alexander Fomichev <fomichev.ru@gmail.com> чт, 1 июл. 2021 г. в 19:47, Bartosz Golaszewski <bgolaszewski@baylibre.com>: > > On Thu, Jul 1, 2021 at 5:28 PM <jglisse@redhat.com> wrote: > > > > From: Jérôme Glisse <jglisse@redhat.com> > > > > We need to append device id even if eeprom have a label property set as some > > platform can have multiple eeproms with same label and we can not register > > each of those with same label. Failing to register those eeproms trigger > > cascade failures on such platform (system is no longer working). > > > > This fix regression on such platform introduced with 4e302c3b568e > > > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > > Cc: Diego Santa Cruz <Diego.SantaCruz@spinetix.com> > > Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> > > Cc: Jon Hunter <jonathanh@nvidia.com> > > Cc: stable@vger.kernel.org > > Cc: linux-i2c@vger.kernel.org > > --- > > drivers/misc/eeprom/at24.c | 17 +++++++---------- > > 1 file changed, 7 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c > > index 7a6f01ace78a..305ffad131a2 100644 > > --- a/drivers/misc/eeprom/at24.c > > +++ b/drivers/misc/eeprom/at24.c > > @@ -714,23 +714,20 @@ static int at24_probe(struct i2c_client *client) > > } > > > > /* > > - * If the 'label' property is not present for the AT24 EEPROM, > > - * then nvmem_config.id is initialised to NVMEM_DEVID_AUTO, > > - * and this will append the 'devid' to the name of the NVMEM > > - * device. This is purely legacy and the AT24 driver has always > > - * defaulted to this. However, if the 'label' property is > > - * present then this means that the name is specified by the > > - * firmware and this name should be used verbatim and so it is > > - * not necessary to append the 'devid'. > > + * We initialize nvmem_config.id to NVMEM_DEVID_AUTO even if the > > + * label property is set as some platform can have multiple eeproms > > + * with same label and we can not register each of those with same > > + * label. Failing to register those eeproms trigger cascade failure > > + * on such platform. > > */ > > + nvmem_config.id = NVMEM_DEVID_AUTO; > > + > > if (device_property_present(dev, "label")) { > > - nvmem_config.id = NVMEM_DEVID_NONE; > > err = device_property_read_string(dev, "label", > > &nvmem_config.name); > > if (err) > > return err; > > } else { > > - nvmem_config.id = NVMEM_DEVID_AUTO; > > nvmem_config.name = dev_name(dev); > > } > > > > -- > > 2.31.1 > > > > Cc'ing Alexander Fomichev who reported this issue first. > > This is the second time someone raises this problem so it seems that > this change really broke many existing systems. I will apply this > patch and send it for stable. > > Bart
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index 7a6f01ace78a..305ffad131a2 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -714,23 +714,20 @@ static int at24_probe(struct i2c_client *client) } /* - * If the 'label' property is not present for the AT24 EEPROM, - * then nvmem_config.id is initialised to NVMEM_DEVID_AUTO, - * and this will append the 'devid' to the name of the NVMEM - * device. This is purely legacy and the AT24 driver has always - * defaulted to this. However, if the 'label' property is - * present then this means that the name is specified by the - * firmware and this name should be used verbatim and so it is - * not necessary to append the 'devid'. + * We initialize nvmem_config.id to NVMEM_DEVID_AUTO even if the + * label property is set as some platform can have multiple eeproms + * with same label and we can not register each of those with same + * label. Failing to register those eeproms trigger cascade failure + * on such platform. */ + nvmem_config.id = NVMEM_DEVID_AUTO; + if (device_property_present(dev, "label")) { - nvmem_config.id = NVMEM_DEVID_NONE; err = device_property_read_string(dev, "label", &nvmem_config.name); if (err) return err; } else { - nvmem_config.id = NVMEM_DEVID_AUTO; nvmem_config.name = dev_name(dev); }