Messages in this thread | | | From | Jean-Michel Hautbois <> | Date | Fri, 2 Nov 2018 14:35:26 +0100 | Subject | sama5d: using the ebi interface from another driver |
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Hi all,
I have a custom board based on a sama5d3 chip. The SoC is connected to 2 pef24628 SHDSL transceivers, the first one on ebi@40000000 and the second one on ebi@50000000. I tried to write a basic char driver, using request_mem_region and ioremap but I can't read or write into the device. I have to say that the driver is based on a proprietary one, and tested years ago on a PowerPC board.
Then, after looking into deeper details in the datasheet I understand it is connected through EBI and it sounds not so easy :D.
I would appreciate some help/pointers on this, as there is (at least, I could find) few documentation on how to use it except for NAND cases.
I have something like that in my DTS, but not sure this is the correct way to do it :
ebi: ebi@10000000 { pinctrl-0 = <&pinctrl_ebi_nand_addr>; pinctrl-names = "default"; status = "okay";
dsp0: pef24628@1 { status = "okay"; compatible = "intel,pef24628"; #address-cells = <1>; #size-cells = <1>; reg = <0x1 0x0 0x8000>; pinctrl-0 = <&pinctrl_dsp_cs1>; };
dsp1: pef24628@2 { status = "okay"; compatible = "intel,pef24628"; #address-cells = <1>; #size-cells = <1>; reg = <0x2 0x0 0x8000>; pinctrl-0 = <&pinctrl_dsp_cs2>; };
nand_controller: nand-controller { status = "okay";
nand@3 { reg = <0x3 0x0 0x2>; atmel,rb = <0>; nand-bus-width = <8>; nand-ecc-mode = "hw"; nand-ecc-strength = <4>; nand-ecc-step-size = <512>; nand-on-flash-bbt; label = "atmel_nand";
partitions { compatible = "fixed-partitions"; #address-cells = <1>; #size-cells = <1>; [...] }; }; };
The pinctrl for ebi should probably be changed however, I am wondering how the (platform ?) driver can access the adress ? Should it parse itself the parent, and find range, etc. Or is there an accessor for it ?
Maybe can I just manually toggle the CS GPIO, and don't try to make anything more complex than what it should be ? The driver should not be atmel dependant...
Thanks ! JM
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