WIFI Device on i.MX28 with mainline Linux 3.8.2 and Device Tree

joilg · ‎03-13-2013

Hello all,

has anybody already an SDIO Wifi Device with I.MX28, mainline kernel and device tree running?

I' trying to setup a SDIO Wifi Module connected on the SSP2 interface.

Reset of the module is connected to MX28_PAD_SSP0_DATA4__GPIO_2_4 active low when reset.

Power of the module is switched on with MX28_PAD_SSP0_DATA5__GPIO_2_5 high.

I add this in my dts file:

apb@80000000 {

apbh@80000000 {

....

ssp2: ssp@80014000 {

compatible = "fsl,imx28-mmc";

pinctrl-names = "default";

pinctrl-0 = <&mmc2_4bit_pins_atm28 &mmc2_sck_cfg_atm28>;

bus-width = <4>;

cd-gpios = <&gpio2 4 0>;

cd-inverted;

vmmc-supply = <&reg_vddio_sd2>;

status = "okay";

};

pinctrl@80018000 {

pinctrl-names = "default";

pinctrl-0 = <&hog_pins_a>;

hog_pins_a: hog@0 {

reg = <0>;

fsl,pinmux-ids = <

0x2043 /* MX28_PAD_SSP0_DATA4__GPIO_2_4 WLAN_RESET/DETECT */

0x2053 /* MX28_PAD_SSP0_DATA5__GPIO_2_5 WLAN_PWRDNN */

>;

fsl,drive-strength = <0>;

fsl,voltage = <1>;

fsl,pull-up = <0>;

};

...

mmc2_4bit_pins_atm28: mmc2-4bit-atm28@0 {

reg = <0>;

fsl,pinmux-ids = <

0x2110 /* MX28_PAD_SSP2_MOSI__SSP2_CMD */

0x2100 /* MX28_PAD_SSP2_SCK__SSP2_SCK */

0x2120 /* MX28_PAD_SSP2_MISO__SSP2_D0 */

0x2141 /* MX28_PAD_SSP2_SS1__SSP2_D1 */

0x2151 /* MX28_PAD_SSP2_SS2__SSP2_D2 */

0x2130 /* MX28_PAD_SSP2_SS0__SSP2_D3 */

>;

fsl,drive-strength = <1>; /* 8mA */

fsl,voltage = <1>; /* 3.3V */

fsl,pull-up = <1>; /* pull up */

};

mmc2_sck_cfg_atm28: mmc2-sck-cfg-atm28@0 {

fsl,pinmux-ids = <

0x2100 /* MX28_PAD_SSP2_SCK__SSP2_SCK */

>;

fsl,drive-strength = <2>; /* 12mA */

fsl,voltage = <1>; /* 3.3V */

fsl,pull-up = <0>; /* pull up */

};

....

regulators {

....

reg_vddio_sd2: vddio-sd2 {

compatible = "regulator-fixed";

regulator-name = "vddio-sd2";

regulator-min-microvolt = <3300000>;

regulator-max-microvolt = <3300000>;

gpio = <&gpio2 5 0>;

startup-delay-us = <70000>;

enable-active-high;

};

....

dmesg

...

[ 0.656781] of_get_named_gpio_flags exited with status 124

[ 0.658312] vddio-sd0: 3300 mV

[ 0.662343] reg-fixed-voltage vddio-sd0.7: vddio-sd0 supplying 3300000uV

[ 0.662625] of_get_named_gpio_flags exited with status 69 <<<<<<<

[ 0.663906] vddio-sd2: 3300 mV

[ 0.667468] reg-fixed-voltage vddio-sd2.8: vddio-sd2 supplying 3300000uV

...

[ 38.504406] libertas_sdio: Libertas SDIO driver

[ 38.509156] libertas_sdio: Copyright Pierre Ossman

dmesg | grep mmc

[ 0.000000] Kernel command line: console=ttyAMA0,115200 gpmi ubi.mtd=7 root=/dev/mmcblk0p3 rw rootwait

[ 1.731156] mxs-mmc 80010000.ssp: Looking up vmmc-supply from device tree

[ 1.767187] mxs-mmc 80010000.ssp: initialized

[ 1.772562] mxs-mmc 80014000.ssp: Looking up vmmc-supply from device tree

[ 1.887187] mxs-mmc 80014000.ssp: initialized

[ 1.904687] mmc0: new SDHC card at address e624

[ 1.921593] mmcblk0: mmc0:e624 SU04G 3.69 GiB

[ 1.950718] mmcblk0: p1 p2 p3

dmesg | grep sdio

[ 38.504406] libertas_sdio: Libertas SDIO driver

[ 38.509156] libertas_sdio: Copyright Pierre Ossman

cat /sys/kernel/debug/mmc1/ios

clock: 0 Hz

vdd: 0 (invalid)

bus mode: 1 (open drain)

chip select: 0 (don't care)

power mode: 0 (off)

bus width: 0 (1 bits)

timing spec: 0 (legacy)

signal voltage: 0 (3.30 V)

I missed something similar to mmc1: new SDIO card at .. in the system log. Also mmc1/ios didn't show correct data.

mmc0 connected to a MMC card works well.

I cannot enable debug for mmc. it results in to many outputs for mmc0.

Please help me how to setup the dts file correctly.

Thanks in advance.

Johannes

fabio_estevam · ‎03-13-2013

Johannes,

Please post this to the linux-arm-kernel mailig list and we will help you from there.

Regards,

Fabio Estevam

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