Chipselect in SPI binding with mpc5200-psc-spi
Grant Likely
grant.likely at secretlab.ca
Thu Oct 30 01:45:30 EST 2008
On Wed, Oct 29, 2008 at 7:43 AM, Henk Stegeman <henk.stegeman at gmail.com> wrote:
> ..
> ..
> In my dts
>
> I have my chipselect defined as follows:
>
> gpt4: timer at 640 { // General Purpose Timer GPT4 in GPIO mode for
> SMC4000IO chip select.
> compatible = "fsl,mpc5200b-gpt-gpio","fsl,mpc5200-gpt-gpio";
> cell-index = <4>;
> reg = <0x640 0x10>;
> interrupts = <1 13 0>;
> interrupt-parent = <&mpc5200_pic>;
> gpio-controller;
> #gpio-cells = <2>;
> };
>
> I found the gpio in
> # cat /sys/class/gpio/gpiochip215/label
> /soc5200 at f0000000/timer at 640
>
> The spi controller is defined like this:
>
> spi at 2400 {
> device_type = "spi";
> #address-cells = <1>;
> #size-cells = <0>;
> compatible = "fsl,mpc5200-psc-spi","fsl,mpc5200b-psc-spi";
> cell-index = <2>;
> reg = <2400 100>;
> interrupts = <2 3 0>;
> interrupt-parent = <&mpc5200_pic>;
> gpios = <&gpt4 0 0>;
>
> io-controller at 0 {
> compatible = "microkey,smc4000io";
> spi-max-frequency = <1000000>;
> reg = <0>;
> };
> };
>
> At bootup linux (2.6.27) reports:
>
> mpc52xx-psc-spi f0000960.spi: probe called without platform data, no
> (de)activate_cs function will be called.
>
> Is my assumption wrong that the gpios property is the way to map chipselects
> to the spi driver?
Yes, that is the way you should work specify the chip selects, but the
driver hasn't been updated to support it yet.
g.
--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
More information about the Linuxppc-dev
mailing list