[PATCH v3 3/4] mmc: omap_hsmmc: Remux pins to support SDIO interrupt on AM335x

NeilBrown neilb at suse.de
Fri Oct 18 02:20:53 EDT 2013


On Sat,  5 Oct 2013 13:17:09 +0200 Andreas Fenkart <afenkart at gmail.com> wrote:

> The am335x can't detect pending cirq in PM runtime suspend.
> This patch reconfigures dat1 as a GPIO before going to suspend.
> SDIO interrupts are detected with the GPIO, while in runtime
> suspend, standard detection of the module block otherwise.
> 
> Signed-off-by: Andreas Fenkart <afenkart at gmail.com>
> 
> diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> index 1136e6b..146f3ad 100644
> --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> @@ -21,8 +21,11 @@ ti,non-removable: non-removable slot (like eMMC)
>  ti,needs-special-reset: Requires a special softreset sequence
>  ti,needs-special-hs-handling: HSMMC IP needs special setting for handling High Speed
>  ti,quirk-swakup-missing: SOC missing the swakeup line, will not detect
> -SDIO irq while in suspend. Fallback to polling. Affected chips are
> -am335x,
> +SDIO irq while in suspend. The workaround is to reconfigure the dat1 line as a
> +GPIO upon suspend. Beyond this option and the GPIO config, you also need to set
> +named pinctrl states "default", "active" and "idle ", see example below.  The
> +MMC driver will then then toggle between default and idle during the runtime
> +Affected chips are am335x,
>  
>                              ------
>                              | PRCM |
> @@ -49,3 +52,24 @@ Example:
>  		vmmc-supply = <&vmmc>; /* phandle to regulator node */
>  		ti,non-removable;
>  	};
> +
> +[am335x with with gpio for sdio irq]
> +
> +	mmc1_cirq_pin: pinmux_cirq_pin {
> +		pinctrl-single,pins = <
> +			0x0f8 0x3f	/* MMC0_DAT1 as GPIO2_28 */
> +		>;
> +	};
> +
> +	mmc1: mmc at 48060000 {
> +		ti,non-removable;
> +		bus-width = <4>;
> +		vmmc-supply = <&ldo2_reg>;
> +		vmmc_aux-supply = <&vmmc>;
> +	        ti,quirk-swakeup-missing;
> +		pinctrl-names = "default", "active", "idle";
> +		pinctrl-0 = <&mmc1_pins>;
> +		pinctrl-1 = <&mmc1_pins>;
> +		pinctrl-2 = <&mmc1_cirq_pin>;
> +		ti,cirq-gpio = <&gpio3 28 0>;
> +	};


hi,
 I've been trying to get SD irq to work on my  OMAP3 DM3730.
I seems to need the magic to catch interrupts while FCLK is off, as
the only way I can get it to work at the moment is to keep FCLK on.

I discovered your patch and tried it out, but it doesn't seem to work for me.

I have a Libertas WIFI chip attached to the second mmc (which is sometimes
called mmc1, and sometimes mmc2 - very confusing!).
I added:
	mmc2_cirq_pin: pinmux_cirq_pin {
		pinctrl-single,pins = <
			0x012e (PIN_INPUT_PULLUP | MUX_MODE4)	/* MMC2_DAT1 as GPIO5_5 */
		>;
	};

and

&mmc2 {
	ti,quirk-swakeup-missing;
	pinctrl-names = "default", "active", "idle";
	pinctrl-0 = <&mmc2_pins>;
	pinctrl-1 = <&mmc2_pins>;
	pinctrl-2 = <&mmc2_cirq_pin>;
	ti,cirq-gpio = <&gpio5 5 0>; /* GPIO133 = 128+5 */
};

to my dts file but it doesn't make any apparent difference.

Any idea what I might be doing wrong?
(the base kernel I am applying patches to is from 8th Oct,
 commit 0e7a3ed04f0cd4311096d691888f88569310ee6c)

BTW,
 - with the default polling, I get about 1Mb/sec with iperf
 - with sd-irq enabled and FCLK kept on the whole time, I get 4Mb/sec
 - with sd-irq enable, FCLK kept on, and the 5ms polling also
   running, I get over 5Mb/sec!
Still much less than the 40Mb/sec that I would like to get...

Thanks,
NeilBrown
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