Hello ;
I am writing mipi csi-2 camera driver on linux target board i.MX6Q but I have problem about communication enable signal. I have the technical data sheet in my hand .But the communication enable register or another info about how to set or get this signal is not mentioned. In this specification I need to give XCE signal to start communication with camera and I have 4 wire serial data lanes and I2C lanes. How can I access this XCE lane to give high and low values to start communication . It would be from device tree or directly accessing the corresponding XCE register from Wandboard Quad. I couldnt find which register address or how to access this XCE signal from device tree. These are the neccessary informations about XCE signal from camera datasheet;
1. XCE: Communication enable 4-wire: XCE pin and I2C: Fixed to High
2.The pin for 4-wire serial communication and I2C communication is shared, so the external pin XCE must be fixed to power supply side when using I2C communication

Also the schematic of the communication is attached . It would be helpful to look at I think.

These are the some information about that other information of XCE is about how to use it while configuring camera . I need some advice or any idea to figure out how to solve this issue.

Thanks.

Best Regards

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The disgram you supply contradicts the information you have. Only one of them can be right. Looking at the diagram. I am no i2c expert and this is datasheet reading & inspired guesswork only.

XCLR = Some class of active low reset. It should be /XCLR (bar over the top indicating active low)
XCE = Chip Enable; low during comms activity.
SCK = Some class of clock controlling the baud rate.
SDI, SDO = Data In & Out.

Is that what you're looking for? I don't see this working with XCE high. But you clearly need power from somewhere, and you might be following instructions for a different circumstance.

Thanks for your reply after your post I realized that I didnt specify what i need .I will edit the question sorry. In this specification I need to give XCE signal to start communication with camera and I have 4 wire serial data lanes . How can I access this XCE lane to give high and low values to start communication . It would be from device tree or directly accessing the XCE register from Wandboard Quad. I couldnt find which register address or How to access this XCE signal from device tree.

That's an electronic hardware problem, usually handled by a particular piece of software, usually a driver or low level comms program. XCE should be handled by the driver for the i2c port and you shouldn't have to worry about it. That's what firmware often does - manage the (perhaps non x86) hardware peripherals in your box.

No great ideas for you beyond look for something in the kernel, or elsewhere that does the job. Identify your i2c devicem and see drives it. I see you're not quibbling with my "analysis."