[PATCH v4 12/13] mmc: add DT bindings for more MMC capability flags

Guennadi Liakhovetski g.liakhovetski at gmx.de
Mon Feb 18 19:52:43 EST 2013


Hi Sergei

On Sun, 17 Feb 2013, Sergei Shtylyov wrote:

> Hello.
> 
> On 02/15/2013 06:14 PM, Guennadi Liakhovetski wrote:
> 
> > Many MMC capability flags are platform-dependent and are traditionally set
> > in platform data. With DT often each such capability requires a special
> > binding. Add bindings for MMC_CAP_SD_HIGHSPEED, MMC_CAP_MMC_HIGHSPEED,
> > MMC_CAP_POWER_OFF_CARD and MMC_CAP_SDIO_IRQ capabilities. Also add code to
> > DT parser to look up "keep-power-in-suspend" and "enable-sdio-wakeup"
> > bindings and set MMC_PM_KEEP_POWER and MMC_PM_WAKE_SDIO_IRQ respectively,
> > if found.
> > 
> > Signed-off-by: Guennadi Liakhovetski<g.liakhovetski at gmx.de>
> > ---
> >   Documentation/devicetree/bindings/mmc/mmc.txt |    4 ++++
> >   drivers/mmc/core/host.c                       |   13 +++++++++++++
> >   2 files changed, 17 insertions(+), 0 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/mmc/mmc.txt
> > b/Documentation/devicetree/bindings/mmc/mmc.txt
> > index 24c8552..d9ab51f 100644
> > --- a/Documentation/devicetree/bindings/mmc/mmc.txt
> > +++ b/Documentation/devicetree/bindings/mmc/mmc.txt
> > @@ -25,6 +25,10 @@ Optional properties:
> >   - max-frequency: maximum operating clock frequency
> >   - no-1-8-v: when present, denotes that 1.8v card voltage is not supported
> > on
> >     this system, even if the controller claims it is.
> > +- cap-sd-highspeed: SD high-speed timing is supported
> > +- cap-mmc-highspeed: MMC high-speed timing is supported
> > +- cap-power-off-card: powering off the card is safe
> > +- cap-sdio-irq: enable SDIO IRQ signalling on this interface
> > 
> >   *NOTE* on CD and WP polarity. To use common for all SD/MMC host
> > controllers line
> >   polarity properties, we have to fix the meaning of the "normal" and
> > "inverted"
> > diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c
> > index daa2ed1..1365466 100644
> > --- a/drivers/mmc/core/host.c
> > +++ b/drivers/mmc/core/host.c
> > @@ -398,6 +398,19 @@ void mmc_of_parse(struct mmc_host *host)
> >   	}
> >   	if (explicit_inv_wp ^ gpio_inv_wp)
> >   		host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;
> > +
> > +	if (of_find_property(np, "cap-sd-highspeed",&len))
> > +		host->caps |= MMC_CAP_SD_HIGHSPEED;
> > +	if (of_find_property(np, "cap-mmc-highspeed",&len))
> > +		host->caps |= MMC_CAP_MMC_HIGHSPEED;
> > +	if (of_find_property(np, "cap-power-off-card",&len))
> > +		host->caps |= MMC_CAP_POWER_OFF_CARD;
> > +	if (of_find_property(np, "cap-sdio-irq",&len))
> > +		host->caps |= MMC_CAP_SDIO_IRQ;
> > +	if (of_find_property(np, "keep-power-in-suspend",&len))
> > +		host->pm_caps |= MMC_PM_KEEP_POWER;
> > +	if (of_find_property(np, "enable-sdio-wakeup",&len))
> > +		host->pm_caps |= MMC_PM_WAKE_SDIO_IRQ;
> >    
> 
>    Why are you not using of_property_read_bool() instead?

Because it's the same. Where I need a boolean return value I so use 
of_property_read_bool(), e.g.

	explicit_inv_cd = of_property_read_bool(np, "cd-inverted");

But where I just need to check, whether a property is present, using 
of_find_property() isn't any worse, IMHO.

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/


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