Re: [PATCH] rtc: jz4740: Add support for the JZ4725B, JZ4760, JZ4770

[Paul Cercueil]

Le sam. 14 juil. 2018 à 15:32, Alexandre Belloni 
<alexandre.belloni@xxxxxxxxxxx> a écrit :
> On 14/07/2018 15:25:33+0200, Paul Cercueil wrote:
> >  Hi Alexandre,
> >
> >  Le sam. 14 juil. 2018 à 15:19, Alexandre Belloni
> >  <alexandre.belloni@xxxxxxxxxxx> a écrit :
> >  > Hello,
> >  >
> >  > On 13/07/2018 17:14:24+0200, Paul Cercueil wrote:
> >  > >  The RTC in the JZ4725B works just like the one in the JZ4740.
> >  > >
> >  > >  The RTC in the JZ4760 and JZ4770 work just like the one in the
> >  > > JZ4780.
> >  > >
> >  > >  Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> >  > >  ---
> >  > >   Documentation/devicetree/bindings/rtc/ingenic,jz4740-rtc.txt 
> > |  3
> >  > > +++
> >  > >   drivers/rtc/rtc-jz4740.c                                     
> > | 11
> >  > > ++++++++++-
> >  > >   2 files changed, 13 insertions(+), 1 deletion(-)
> >  > >
> >  > >  diff --git
> >  > > a/Documentation/devicetree/bindings/rtc/ingenic,jz4740-rtc.txt
> >  > > b/Documentation/devicetree/bindings/rtc/ingenic,jz4740-rtc.txt
> >  > >  index 41c7ae18fd7b..a9e821de84f2 100644
> >  > >  --- 
> > a/Documentation/devicetree/bindings/rtc/ingenic,jz4740-rtc.txt
> >  > >  +++ 
> > b/Documentation/devicetree/bindings/rtc/ingenic,jz4740-rtc.txt
> >  > >  @@ -4,6 +4,9 @@ Required properties:
> >  > >
> >  > >   - compatible: One of:
> >  > >     - "ingenic,jz4740-rtc" - for use with the JZ4740 SoC
> >  > >  +  - "ingenic,jz4725b-rtc" - for use with the JZ4725B SoC
> >  > >  +  - "ingenic,jz4760-rtc" - for use with the JZ4760 SoC
> >  > >  +  - "ingenic,jz4770-rtc" - for use with the JZ4770 SoC
> >  > >     - "ingenic,jz4780-rtc" - for use with the JZ4780 SoC
> >  > >   - reg: Address range of rtc register set
> >  > >   - interrupts: IRQ number for the alarm interrupt
> >  > >  diff --git a/drivers/rtc/rtc-jz4740.c 
> > b/drivers/rtc/rtc-jz4740.c
> >  > >  index d0a891777f44..1c867e3a0ea5 100644
> >  > >  --- a/drivers/rtc/rtc-jz4740.c
> >  > >  +++ b/drivers/rtc/rtc-jz4740.c
> >  > >  @@ -54,6 +54,9 @@
> >  > >
> >  > >   enum jz4740_rtc_type {
> >  > >   	ID_JZ4740,
> >  > >  +	ID_JZ4725B,
> >  > >  +	ID_JZ4760,
> >  > >  +	ID_JZ4770,
> >  >
> >  > I wouldn't introduce those ids unless there are handling 
> > differences at
> >  > some point.
> >
> >  Well there are handling differences, see below.
> >
> >  > >   	ID_JZ4780,
> >  > >   };
> >  > >
> >  > >  @@ -114,7 +117,7 @@ static inline int 
> > jz4740_rtc_reg_write(struct
> >  > > jz4740_rtc *rtc, size_t reg,
> >  > >   {
> >  > >   	int ret = 0;
> >  > >
> >  > >  -	if (rtc->type >= ID_JZ4780)
> >  > >  +	if (rtc->type >= ID_JZ4760)
> >  >
> >  > This would avoid that change (and the test would preferably be
> >  > (rtc->type == ID_JZ4780))
> >
> >  That branch should be taken if the SoC is JZ4760, JZ4770 or JZ4780.
> >  It should not be taken if the SoC is JZ4740 or JZ4725B.
>
> Sure but you can achieve that with only 2 ids...
>
> >  > >   		ret = jz4780_rtc_enable_write(rtc);
> >  > >   	if (ret == 0)
> >  > >   		ret = jz4740_rtc_wait_write_ready(rtc);
> >  > >  @@ -300,6 +303,9 @@ static void jz4740_rtc_power_off(void)
> >  > >
> >  > >   static const struct of_device_id jz4740_rtc_of_match[] = {
> >  > >   	{ .compatible = "ingenic,jz4740-rtc", .data = (void 
> > *)ID_JZ4740 },
> >  > >  +	{ .compatible = "ingenic,jz4725b-rtc", .data = (void 
> > *)ID_JZ4725B
> >  > > },
> >  > >  +	{ .compatible = "ingenic,jz4760-rtc", .data = (void 
> > *)ID_JZ4760 },
> >  > >  +	{ .compatible = "ingenic,jz4770-rtc", .data = (void 
> > *)ID_JZ4770 },
>
> By doing the correct mapping here e.g:
>
> { .compatible = "ingenic,jz4725b-rtc", .data = (void *)ID_JZ4740 },

Not very pretty and future-proof if you ask me...
But you're the boss...

> >  > >   	{ .compatible = "ingenic,jz4780-rtc", .data = (void 
> > *)ID_JZ4780 },
> >  > >   	{},
> >  > >   };
> >  > >  @@ -428,6 +434,9 @@ static const struct dev_pm_ops 
> > jz4740_pm_ops = {
> >  > >
> >  > >   static const struct platform_device_id jz4740_rtc_ids[] = {
> >  > >   	{ "jz4740-rtc", ID_JZ4740 },
> >  > >  +	{ "jz4725b-rtc", ID_JZ4725B },
> >  > >  +	{ "jz4760-rtc", ID_JZ4760 },
> >  > >  +	{ "jz4770-rtc", ID_JZ4770 },
>
> And here
>
> >  > >   	{ "jz4780-rtc", ID_JZ4780 },
> >  > >   	{}
> >  > >   };
> >  > >  --
> >  > >  2.11.0
> >  > >
> >  >
> >  > --
> >  > Alexandre Belloni, Bootlin (formerly Free Electrons)
> >  > Embedded Linux and Kernel engineering
> >  > https://bootlin.com
>
> --
> Alexandre Belloni, Bootlin (formerly Free Electrons)
> Embedded Linux and Kernel engineering
> https://bootlin.com