| Message ID | 1508961173-22686-1-git-send-email-eajames@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
On Wed, Oct 25, 2017 at 02:52:53PM -0500, Eddie James wrote: > From: "Edward A. James" <eajames@us.ibm.com> > > For devices with word data registers, the pmbus core may call read/write > word data functions with a page value of -1, in order to perform the > operation without setting the page. However, the read/write word data > functions accept only unsigned 8-bit page numbers, resulting in setting > a page of 0xFF in this situation. This may result in errors or undefined > behavior of some devices (specifically the ir35221, which allows the > page to be set to 0xFF, but some subsequent operations to read registers > may fail). > Good catch. Subject came off a bit odd. [prefix=PATCH] drivers: pmbus: core: Prevent ... Please use "[PATCH] hwmon: (pmbus/core) Prevent ..." This me wonder if we should move the check into pmbus_set_page() instead. int pmbus_set_page(struct i2c_client *client, int page) { ... if (page >= 0 && page != data->currpage) { ... } What do you think ? Thanks, Guenter > Signed-off-by: Edward A. James <eajames@us.ibm.com> > --- > drivers/hwmon/pmbus/pmbus.h | 4 ++-- > drivers/hwmon/pmbus/pmbus_core.c | 29 ++++++++++++++++++----------- > 2 files changed, 20 insertions(+), 13 deletions(-) > > diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h > index 4efa2bd..4a16da6 100644 > --- a/drivers/hwmon/pmbus/pmbus.h > +++ b/drivers/hwmon/pmbus/pmbus.h > @@ -405,8 +405,8 @@ struct pmbus_driver_info { > > void pmbus_clear_cache(struct i2c_client *client); > int pmbus_set_page(struct i2c_client *client, u8 page); > -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg); > -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word); > +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg); > +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, u16 word); > int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg); > int pmbus_write_byte(struct i2c_client *client, int page, u8 value); > int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, > diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c > index 302f0ae..6d6e030 100644 > --- a/drivers/hwmon/pmbus/pmbus_core.c > +++ b/drivers/hwmon/pmbus/pmbus_core.c > @@ -186,13 +186,16 @@ static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value) > return pmbus_write_byte(client, page, value); > } > > -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word) > +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, > + u16 word) > { > int rv; > > - rv = pmbus_set_page(client, page); > - if (rv < 0) > - return rv; > + if (page >= 0) { > + rv = pmbus_set_page(client, page); > + if (rv < 0) > + return rv; > + } > > return i2c_smbus_write_word_data(client, reg, word); > } > @@ -219,13 +222,15 @@ static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg, > return pmbus_write_word_data(client, page, reg, word); > } > > -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg) > +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg) > { > int rv; > > - rv = pmbus_set_page(client, page); > - if (rv < 0) > - return rv; > + if (page >= 0) { > + rv = pmbus_set_page(client, page); > + if (rv < 0) > + return rv; > + } > > return i2c_smbus_read_word_data(client, reg); > } > @@ -269,9 +274,11 @@ int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value) > { > int rv; > > - rv = pmbus_set_page(client, page); > - if (rv < 0) > - return rv; > + if (page >= 0) { > + rv = pmbus_set_page(client, page); > + if (rv < 0) > + return rv; > + } > > return i2c_smbus_write_byte_data(client, reg, value); > } > -- > 1.8.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 10/25/2017 04:12 PM, Guenter Roeck wrote: > On Wed, Oct 25, 2017 at 02:52:53PM -0500, Eddie James wrote: >> From: "Edward A. James" <eajames@us.ibm.com> >> >> For devices with word data registers, the pmbus core may call read/write >> word data functions with a page value of -1, in order to perform the >> operation without setting the page. However, the read/write word data >> functions accept only unsigned 8-bit page numbers, resulting in setting >> a page of 0xFF in this situation. This may result in errors or undefined >> behavior of some devices (specifically the ir35221, which allows the >> page to be set to 0xFF, but some subsequent operations to read registers >> may fail). >> > Good catch. > > Subject came off a bit odd. > > [prefix=PATCH] drivers: pmbus: core: Prevent ... > > Please use "[PATCH] hwmon: (pmbus/core) Prevent ..." Yea I hit = instead of - in "--subject-prefix"... > > This me wonder if we should move the check into pmbus_set_page() > instead. > > int pmbus_set_page(struct i2c_client *client, int page) > { > ... > if (page >= 0 && page != data->currpage) { > ... > } > > What do you think ? Yea that works well too, and reduces the code size. Though I suppose it makes the interface slightly less intuitive, as someone might think they can pass a value larger than u8. At least for the read/write functions, a negative value has a meaning - "don't change the page." Up to you, either way. I'm happy to change it. Thanks, Eddie > > Thanks, > Guenter > >> Signed-off-by: Edward A. James <eajames@us.ibm.com> >> --- >> drivers/hwmon/pmbus/pmbus.h | 4 ++-- >> drivers/hwmon/pmbus/pmbus_core.c | 29 ++++++++++++++++++----------- >> 2 files changed, 20 insertions(+), 13 deletions(-) >> >> diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h >> index 4efa2bd..4a16da6 100644 >> --- a/drivers/hwmon/pmbus/pmbus.h >> +++ b/drivers/hwmon/pmbus/pmbus.h >> @@ -405,8 +405,8 @@ struct pmbus_driver_info { >> >> void pmbus_clear_cache(struct i2c_client *client); >> int pmbus_set_page(struct i2c_client *client, u8 page); >> -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg); >> -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word); >> +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg); >> +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, u16 word); >> int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg); >> int pmbus_write_byte(struct i2c_client *client, int page, u8 value); >> int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, >> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c >> index 302f0ae..6d6e030 100644 >> --- a/drivers/hwmon/pmbus/pmbus_core.c >> +++ b/drivers/hwmon/pmbus/pmbus_core.c >> @@ -186,13 +186,16 @@ static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value) >> return pmbus_write_byte(client, page, value); >> } >> >> -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word) >> +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, >> + u16 word) >> { >> int rv; >> >> - rv = pmbus_set_page(client, page); >> - if (rv < 0) >> - return rv; >> + if (page >= 0) { >> + rv = pmbus_set_page(client, page); >> + if (rv < 0) >> + return rv; >> + } >> >> return i2c_smbus_write_word_data(client, reg, word); >> } >> @@ -219,13 +222,15 @@ static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg, >> return pmbus_write_word_data(client, page, reg, word); >> } >> >> -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg) >> +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg) >> { >> int rv; >> >> - rv = pmbus_set_page(client, page); >> - if (rv < 0) >> - return rv; >> + if (page >= 0) { >> + rv = pmbus_set_page(client, page); >> + if (rv < 0) >> + return rv; >> + } >> >> return i2c_smbus_read_word_data(client, reg); >> } >> @@ -269,9 +274,11 @@ int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value) >> { >> int rv; >> >> - rv = pmbus_set_page(client, page); >> - if (rv < 0) >> - return rv; >> + if (page >= 0) { >> + rv = pmbus_set_page(client, page); >> + if (rv < 0) >> + return rv; >> + } >> >> return i2c_smbus_write_byte_data(client, reg, value); >> } >> -- >> 1.8.3.1 >> -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Oct 25, 2017 at 04:23:01PM -0500, Eddie James wrote: > > > On 10/25/2017 04:12 PM, Guenter Roeck wrote: > >On Wed, Oct 25, 2017 at 02:52:53PM -0500, Eddie James wrote: > >>From: "Edward A. James" <eajames@us.ibm.com> > >> > >>For devices with word data registers, the pmbus core may call read/write > >>word data functions with a page value of -1, in order to perform the > >>operation without setting the page. However, the read/write word data > >>functions accept only unsigned 8-bit page numbers, resulting in setting > >>a page of 0xFF in this situation. This may result in errors or undefined > >>behavior of some devices (specifically the ir35221, which allows the > >>page to be set to 0xFF, but some subsequent operations to read registers > >>may fail). > >> > >Good catch. > > > >Subject came off a bit odd. > > > >[prefix=PATCH] drivers: pmbus: core: Prevent ... > > > >Please use "[PATCH] hwmon: (pmbus/core) Prevent ..." > > Yea I hit = instead of - in "--subject-prefix"... > > > > >This me wonder if we should move the check into pmbus_set_page() > >instead. > > > >int pmbus_set_page(struct i2c_client *client, int page) > >{ > > ... > > if (page >= 0 && page != data->currpage) { > > ... > >} > > > >What do you think ? > > Yea that works well too, and reduces the code size. Though I suppose it > makes the interface slightly less intuitive, as someone might think they can > pass a value larger than u8. At least for the read/write functions, a > negative value has a meaning - "don't change the page." > > Up to you, either way. I'm happy to change it. > Let's do it. Thanks, Guenter > Thanks, > Eddie > > > > >Thanks, > >Guenter > > > >>Signed-off-by: Edward A. James <eajames@us.ibm.com> > >>--- > >> drivers/hwmon/pmbus/pmbus.h | 4 ++-- > >> drivers/hwmon/pmbus/pmbus_core.c | 29 ++++++++++++++++++----------- > >> 2 files changed, 20 insertions(+), 13 deletions(-) > >> > >>diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h > >>index 4efa2bd..4a16da6 100644 > >>--- a/drivers/hwmon/pmbus/pmbus.h > >>+++ b/drivers/hwmon/pmbus/pmbus.h > >>@@ -405,8 +405,8 @@ struct pmbus_driver_info { > >> void pmbus_clear_cache(struct i2c_client *client); > >> int pmbus_set_page(struct i2c_client *client, u8 page); > >>-int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg); > >>-int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word); > >>+int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg); > >>+int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, u16 word); > >> int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg); > >> int pmbus_write_byte(struct i2c_client *client, int page, u8 value); > >> int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, > >>diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c > >>index 302f0ae..6d6e030 100644 > >>--- a/drivers/hwmon/pmbus/pmbus_core.c > >>+++ b/drivers/hwmon/pmbus/pmbus_core.c > >>@@ -186,13 +186,16 @@ static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value) > >> return pmbus_write_byte(client, page, value); > >> } > >>-int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word) > >>+int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, > >>+ u16 word) > >> { > >> int rv; > >>- rv = pmbus_set_page(client, page); > >>- if (rv < 0) > >>- return rv; > >>+ if (page >= 0) { > >>+ rv = pmbus_set_page(client, page); > >>+ if (rv < 0) > >>+ return rv; > >>+ } > >> return i2c_smbus_write_word_data(client, reg, word); > >> } > >>@@ -219,13 +222,15 @@ static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg, > >> return pmbus_write_word_data(client, page, reg, word); > >> } > >>-int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg) > >>+int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg) > >> { > >> int rv; > >>- rv = pmbus_set_page(client, page); > >>- if (rv < 0) > >>- return rv; > >>+ if (page >= 0) { > >>+ rv = pmbus_set_page(client, page); > >>+ if (rv < 0) > >>+ return rv; > >>+ } > >> return i2c_smbus_read_word_data(client, reg); > >> } > >>@@ -269,9 +274,11 @@ int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value) > >> { > >> int rv; > >>- rv = pmbus_set_page(client, page); > >>- if (rv < 0) > >>- return rv; > >>+ if (page >= 0) { > >>+ rv = pmbus_set_page(client, page); > >>+ if (rv < 0) > >>+ return rv; > >>+ } > >> return i2c_smbus_write_byte_data(client, reg, value); > >> } > >>-- > >>1.8.3.1 > >> > -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h index 4efa2bd..4a16da6 100644 --- a/drivers/hwmon/pmbus/pmbus.h +++ b/drivers/hwmon/pmbus/pmbus.h @@ -405,8 +405,8 @@ struct pmbus_driver_info { void pmbus_clear_cache(struct i2c_client *client); int pmbus_set_page(struct i2c_client *client, u8 page); -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg); -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word); +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg); +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, u16 word); int pmbus_read_byte_data(struct i2c_client *client, int page, u8 reg); int pmbus_write_byte(struct i2c_client *client, int page, u8 value); int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 302f0ae..6d6e030 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -186,13 +186,16 @@ static int _pmbus_write_byte(struct i2c_client *client, int page, u8 value) return pmbus_write_byte(client, page, value); } -int pmbus_write_word_data(struct i2c_client *client, u8 page, u8 reg, u16 word) +int pmbus_write_word_data(struct i2c_client *client, int page, u8 reg, + u16 word) { int rv; - rv = pmbus_set_page(client, page); - if (rv < 0) - return rv; + if (page >= 0) { + rv = pmbus_set_page(client, page); + if (rv < 0) + return rv; + } return i2c_smbus_write_word_data(client, reg, word); } @@ -219,13 +222,15 @@ static int _pmbus_write_word_data(struct i2c_client *client, int page, int reg, return pmbus_write_word_data(client, page, reg, word); } -int pmbus_read_word_data(struct i2c_client *client, u8 page, u8 reg) +int pmbus_read_word_data(struct i2c_client *client, int page, u8 reg) { int rv; - rv = pmbus_set_page(client, page); - if (rv < 0) - return rv; + if (page >= 0) { + rv = pmbus_set_page(client, page); + if (rv < 0) + return rv; + } return i2c_smbus_read_word_data(client, reg); } @@ -269,9 +274,11 @@ int pmbus_write_byte_data(struct i2c_client *client, int page, u8 reg, u8 value) { int rv; - rv = pmbus_set_page(client, page); - if (rv < 0) - return rv; + if (page >= 0) { + rv = pmbus_set_page(client, page); + if (rv < 0) + return rv; + } return i2c_smbus_write_byte_data(client, reg, value); }