From: Nicholas Mc Guire <[email protected]>
Currently there are a few drivers that still set the .owner
in the i2c_driver structure - all of which are reported by
coccinelle (scripts/coccinelle/api/platform_no_drv_owner.cocci)
and there are no cases that set the .onwer and do not call any
of the functions that set the .owner field anyway in any of the
drivers (checked by a modified coccinelle script based on the
above) so it seems that the examples are no longer valid and
.owner = THIS_MODULE, can be removed here.
While at it an obvious typo (new new) was also fixed.
Signed-off-by: Nicholas Mc Guire <[email protected]>
---
Patch is against 4.15-rc7 (localversion-next is -next-20180112)
Documentation/i2c/upgrading-clients | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)
diff --git a/Documentation/i2c/upgrading-clients b/Documentation/i2c/upgrading-clients
index ccba3ff..d5e51ae 100644
--- a/Documentation/i2c/upgrading-clients
+++ b/Documentation/i2c/upgrading-clients
@@ -7,7 +7,7 @@ Introduction
------------
This guide outlines how to alter existing Linux 2.6 client drivers from
-the old to the new new binding methods.
+the old to the new binding methods.
Example old-style driver
@@ -77,7 +77,6 @@ static int example_attach_adapter(struct i2c_adapter *adap)
static struct i2c_driver example_driver = {
.driver = {
- .owner = THIS_MODULE,
.name = "example",
.pm = &example_pm_ops,
},
@@ -217,7 +216,6 @@ and other utilities:
static struct i2c_driver example_driver = {
.driver = {
- .owner = THIS_MODULE,
.name = "example",
},
+ .id_table = example_ids,
@@ -269,7 +267,6 @@ MODULE_DEVICE_TABLE(i2c, example_idtable);
static struct i2c_driver example_driver = {
.driver = {
- .owner = THIS_MODULE,
.name = "example",
.pm = &example_pm_ops,
},
--
2.1.4
On Mon, Jan 15, 2018 at 2:08 PM, Nicholas Mc Guire <[email protected]> wrote:
> From: Nicholas Mc Guire <[email protected]>
>
> Currently there are a few drivers that still set the .owner
> in the i2c_driver structure - all of which are reported by
> coccinelle (scripts/coccinelle/api/platform_no_drv_owner.cocci)
> and there are no cases that set the .onwer and do not call any
> of the functions that set the .owner field anyway in any of the
> drivers (checked by a modified coccinelle script based on the
> above) so it seems that the examples are no longer valid and
> .owner = THIS_MODULE, can be removed here.
>
> While at it an obvious typo (new new) was also fixed.
AFAIU It is right only in case when someone does this, e.g.
module_i2c_driver() macro. Otherwise the field is pretty valid and
must be filled.
--
With Best Regards,
Andy Shevchenko
On Mon, Jan 15, 2018 at 10:24:52PM +0200, Andy Shevchenko wrote:
> On Mon, Jan 15, 2018 at 2:08 PM, Nicholas Mc Guire <[email protected]> wrote:
> > From: Nicholas Mc Guire <[email protected]>
> >
> > Currently there are a few drivers that still set the .owner
> > in the i2c_driver structure - all of which are reported by
> > coccinelle (scripts/coccinelle/api/platform_no_drv_owner.cocci)
> > and there are no cases that set the .onwer and do not call any
> > of the functions that set the .owner field anyway in any of the
> > drivers (checked by a modified coccinelle script based on the
> > above) so it seems that the examples are no longer valid and
> > .owner = THIS_MODULE, can be removed here.
> >
> > While at it an obvious typo (new new) was also fixed.
>
> AFAIU It is right only in case when someone does this, e.g.
> module_i2c_driver() macro. Otherwise the field is pretty valid and
> must be filled.
It gets filled with i2c_add_driver. module_i2c_driver uses
i2c_add_driver. I was about to suggest to keep the field in the old
driver and describe that it can be removed when using one of
i2c_add_driver or module_i2c_driver.
But then I realised that the kernel tree does not have any such old
drivers anymore and I couldn't even find out-of-tree code via some
search engines (I tried looking for "I2C_CLIENT_INSMOD").
I consider this obsolete and irrelevant these days. It might be good to
simply remove it to not confuse users.
Thoughts?
On Mon, Jan 15, 2018 at 09:28:47PM +0100, Wolfram Sang wrote:
> On Mon, Jan 15, 2018 at 10:24:52PM +0200, Andy Shevchenko wrote:
> > On Mon, Jan 15, 2018 at 2:08 PM, Nicholas Mc Guire <[email protected]> wrote:
> > > From: Nicholas Mc Guire <[email protected]>
> > >
> > > Currently there are a few drivers that still set the .owner
> > > in the i2c_driver structure - all of which are reported by
> > > coccinelle (scripts/coccinelle/api/platform_no_drv_owner.cocci)
> > > and there are no cases that set the .onwer and do not call any
> > > of the functions that set the .owner field anyway in any of the
> > > drivers (checked by a modified coccinelle script based on the
> > > above) so it seems that the examples are no longer valid and
> > > .owner = THIS_MODULE, can be removed here.
> > >
> > > While at it an obvious typo (new new) was also fixed.
> >
> > AFAIU It is right only in case when someone does this, e.g.
> > module_i2c_driver() macro. Otherwise the field is pretty valid and
> > must be filled.
>
> It gets filled with i2c_add_driver. module_i2c_driver uses
> i2c_add_driver. I was about to suggest to keep the field in the old
> driver and describe that it can be removed when using one of
> i2c_add_driver or module_i2c_driver.
>
> But then I realised that the kernel tree does not have any such old
> drivers anymore and I couldn't even find out-of-tree code via some
> search engines (I tried looking for "I2C_CLIENT_INSMOD").
>
> I consider this obsolete and irrelevant these days. It might be good to
> simply remove it to not confuse users.
>
Not sure what the status of this is now - but I would
want to clean up some of the coccinelle findings - as a pre-requisite
it would make sense to either drop the examples inclusion of
.owner = THIS_MODULE or add a note in the documentation making
clear that this is only needed in case where the appropriate
module initialization helpers are not used. Is there any good
reason *not* to use these initialization helpers when upgrading
a driver ? If not (and I could not find one) then it might simply
be the right way to recommend using the initialization helpers and
drop the .owner = THIS_MODULE from the examples.
Anyway - cleaning up coccinelle findings would seem futile if the
documentation may be the cause.
thx!
hofrat