| Message ID | 20140321115541.01cbbb06@armhf (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 03/21/2014 11:55 AM, Jean-Francois Moine wrote: > The tda998x driver accepts only 3 chips from the TDA998x family. > This patch changes the driver compatible strings to these chips. Jean-Francois, be careful with building a DT binding from a Linux driver. Although we constantly struggle to define a binding independent of Linux, it should not reflect what Linux is capable of but describe the HW in general. > Signed-off-by: Jean-Francois Moine <moinejf@free.fr> > --- > v2: change the subject to drm/i2c > This patch applies after > drm/i2c: tda998x: Fix lack of required reg in DT documentation > --- > Documentation/devicetree/bindings/drm/i2c/tda998x.txt | 4 ++-- > drivers/gpu/drm/i2c/tda998x_drv.c | 4 +++- > 2 files changed, 5 insertions(+), 3 deletions(-) > diff --git a/Documentation/devicetree/bindings/drm/i2c/tda998x.txt b/Documentation/devicetree/bindings/drm/i2c/tda998x.txt > index fc7effa..e3f3d65 100644 > --- a/Documentation/devicetree/bindings/drm/i2c/tda998x.txt > +++ b/Documentation/devicetree/bindings/drm/i2c/tda998x.txt > @@ -1,7 +1,7 @@ > Device-Tree bindings for the NXP TDA998x HDMI transmitter > > Required properties; > - - compatible: must be "nxp,tda998x" > + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" There is a "DT is ABI" policy and although there is no mainline Linux user of current compatible, the correct way would be to deprecate "nxp,tda998x" and introduce new compatibles. Also, as long as we don't know about any major differences between 9989, 1998[89] it is fine to just have one of them defined. As soon as we discover any difference that cannot be solved in another way, we can add a new compatible. What we _know_ is that 998[134] are different from 9989,1998[89] with respect to additional CEC feature. But we also _know_ that the exact version/revision of 9989,1998[89] can be probed from i2c registers. DT maintainers will know better, but as long as we have no prove that 998[134] can also be properly distinguished by i2c registers, just add "nxp,tda9989" (which was probably the first revision released) and assume 1998[89] are "compatible enough". Or add all three and make "nxp,tda9989" the mandatory compatible. You can leave out 998[134] for now. > - reg: I2C address > The line above and below reg property look like there is a tab. If so, can you please get rid of the blank line above and fix the line below? > @@ -20,7 +20,7 @@ Optional properties: > Example: > > tda998x: hdmi-encoder { > - compatible = "nxp,tda998x"; > + compatible = "nxp,tda19988"; Depending on above decision this becomes either compatible = "nxp,tda9989"; or compatible = "nxp,tda19988", "nxp,tda9989"; > reg = <0x70>; > interrupt-parent = <&gpio0>; > interrupts = <27 2>; /* falling edge */ > diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c > index 48af5ca..fd6751c 100644 > --- a/drivers/gpu/drm/i2c/tda998x_drv.c > +++ b/drivers/gpu/drm/i2c/tda998x_drv.c > @@ -1367,7 +1367,9 @@ fail: > > #ifdef CONFIG_OF > static const struct of_device_id tda998x_dt_ids[] = { > - { .compatible = "nxp,tda998x", }, > + { .compatible = "nxp,tda9989", }, > + { .compatible = "nxp,tda19988", }, > + { .compatible = "nxp,tda19989", }, Independent of the decision above, just "nxp,tda9989" is sufficient. Sebastian > { } > }; > MODULE_DEVICE_TABLE(of, tda998x_dt_ids); >
On Fri, 21 Mar 2014 14:37:52 +0100 Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> wrote: > > Required properties; > > - - compatible: must be "nxp,tda998x" > > + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" > > There is a "DT is ABI" policy and although there is no mainline Linux > user of current compatible, the correct way would be to deprecate > "nxp,tda998x" and introduce new compatibles. Pratically, what is this way?
On 03/23/2014 11:19 AM, Jean-Francois Moine wrote: > On Fri, 21 Mar 2014 14:37:52 +0100 > Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> wrote: >>> Required properties; >>> - - compatible: must be "nxp,tda998x" >>> + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" >> >> There is a "DT is ABI" policy and although there is no mainline Linux >> user of current compatible, the correct way would be to deprecate >> "nxp,tda998x" and introduce new compatibles. > > Pratically, what is this way? Currently, there is no effective way to deprecate a binding or compatible. You just add the one(s) that are more sensible and you mark the old one as DEPRECATED by simply writing it in the binding doc. The driver should support the old binding at least for a while. Sebastian
On Sun, Mar 23, 2014 at 07:12:05PM +0100, Sebastian Hesselbarth wrote: > On 03/23/2014 11:19 AM, Jean-Francois Moine wrote: >> On Fri, 21 Mar 2014 14:37:52 +0100 >> Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> wrote: >>>> Required properties; >>>> - - compatible: must be "nxp,tda998x" >>>> + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" >>> >>> There is a "DT is ABI" policy and although there is no mainline Linux >>> user of current compatible, the correct way would be to deprecate >>> "nxp,tda998x" and introduce new compatibles. >> >> Pratically, what is this way? > > Currently, there is no effective way to deprecate a binding or > compatible. You just add the one(s) that are more sensible and > you mark the old one as DEPRECATED by simply writing it in the > binding doc. > > The driver should support the old binding at least for a while. It doesn't need to - it's only been in development trees so far, and never been in a mainline full release. Until it does, the binding does not become stable.
On 03/23/2014 09:03 PM, Russell King - ARM Linux wrote: > On Sun, Mar 23, 2014 at 07:12:05PM +0100, Sebastian Hesselbarth wrote: >> On 03/23/2014 11:19 AM, Jean-Francois Moine wrote: >>> On Fri, 21 Mar 2014 14:37:52 +0100 >>> Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> wrote: >>>>> Required properties; >>>>> - - compatible: must be "nxp,tda998x" >>>>> + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" >>>> >>>> There is a "DT is ABI" policy and although there is no mainline Linux >>>> user of current compatible, the correct way would be to deprecate >>>> "nxp,tda998x" and introduce new compatibles. >>> >>> Pratically, what is this way? >> >> Currently, there is no effective way to deprecate a binding or >> compatible. You just add the one(s) that are more sensible and >> you mark the old one as DEPRECATED by simply writing it in the >> binding doc. >> >> The driver should support the old binding at least for a while. > > It doesn't need to - it's only been in development trees so far, and > never been in a mainline full release. Until it does, the binding > does not become stable. Ok, I see. Thanks for the clarification. A note about it would have been nice though. Anyway, sorry for the noise. Sebastian
diff --git a/Documentation/devicetree/bindings/drm/i2c/tda998x.txt b/Documentation/devicetree/bindings/drm/i2c/tda998x.txt index fc7effa..e3f3d65 100644 --- a/Documentation/devicetree/bindings/drm/i2c/tda998x.txt +++ b/Documentation/devicetree/bindings/drm/i2c/tda998x.txt @@ -1,7 +1,7 @@ Device-Tree bindings for the NXP TDA998x HDMI transmitter Required properties; - - compatible: must be "nxp,tda998x" + - compatible: may be "nxp,tda9989", "nxp,tda19988" or "nxp,tda19989" - reg: I2C address @@ -20,7 +20,7 @@ Optional properties: Example: tda998x: hdmi-encoder { - compatible = "nxp,tda998x"; + compatible = "nxp,tda19988"; reg = <0x70>; interrupt-parent = <&gpio0>; interrupts = <27 2>; /* falling edge */ diff --git a/drivers/gpu/drm/i2c/tda998x_drv.c b/drivers/gpu/drm/i2c/tda998x_drv.c index 48af5ca..fd6751c 100644 --- a/drivers/gpu/drm/i2c/tda998x_drv.c +++ b/drivers/gpu/drm/i2c/tda998x_drv.c @@ -1367,7 +1367,9 @@ fail: #ifdef CONFIG_OF static const struct of_device_id tda998x_dt_ids[] = { - { .compatible = "nxp,tda998x", }, + { .compatible = "nxp,tda9989", }, + { .compatible = "nxp,tda19988", }, + { .compatible = "nxp,tda19989", }, { } }; MODULE_DEVICE_TABLE(of, tda998x_dt_ids);
The tda998x driver accepts only 3 chips from the TDA998x family. This patch changes the driver compatible strings to these chips. Signed-off-by: Jean-Francois Moine <moinejf@free.fr> --- v2: change the subject to drm/i2c This patch applies after drm/i2c: tda998x: Fix lack of required reg in DT documentation --- Documentation/devicetree/bindings/drm/i2c/tda998x.txt | 4 ++-- drivers/gpu/drm/i2c/tda998x_drv.c | 4 +++- 2 files changed, 5 insertions(+), 3 deletions(-)