Hi, Herbert, all, I need an advice. I'm writing a driver for a crypto device that communicates over I2C. Reads and writes from/to the i2c device are sequential, I use a lock to synchronize the requests. There are no interrupts for the i2c client. Each request has to send a command, to wait for an estimated time so that the device finishes to execute the command and then to read the result. The crypto requests can be in atomic context. The maximum execution time of a command in my crypto device is 115 milliseconds. Using a spinlock to synchronize the requests and udelay for waiting the device to finish the execution will block the core for at least 115 milliseconds. If someone floods me with requests in atomic context, the core will be doomed. As of now I see two possibilities when treating requests in atomic context: 1. fallback to the software implementation and hope that it's faster than my hw. My device is capable of doing ecc privkey generation, ecdh and ecdsa. 2. use spinlock and udelay and block the core. What would you advise me, how should I treat requests in atomic context? Thanks, ta
