hi all, once again i' having trouble getting things to work. maybe someone here has more experience with at least one of these issues. i'm working on a driver for a radio/rd(b)s device. the rds (radio-data-system) chip is attached via i2c. it triggers an interrupt when data has been decoded (~ every 20ms). the data will be read from the v4l device, the tuner is controlled by ioctls on that same device. all of this does work (in a way). i've tried several scenarios: 1) reading from the device, i wait in a wait queue. an interrupt does a wakeup. then the read process does a i2c_master_recv directly. works. 2) i assign a buffer for a single piece of data. reading from the device, i wait in a wait queue. an interrupt schedules a tasklet. the tasklet read the data over i2c, stores it in the buffer and does a wakeup. then the read process reads the data out of the buffer. works. 3) i assign a ringbuffer for the data. reading from the device, i do a wait_event_interruptible on the ringbuffer. when passed, i disable_tasklet, read the data and enable_tasklet. in the interrupt i schedule_tasklet. in the tasklet i do the buffer handling and try to i2c_master_recv. then i get a kernel panic (AIEE ...). leaving out only the actual receive does work (although i get no data). i don't see, where case 3 is significantly different from case 2. where do i cause the kernel panic? any ideas? regards, -- _ plain GmbH_______________________________________________________ markus schorer fon 089.540.149.0 daiserstrasse 15 RGB fax 089.540.149.44 81371 m?nchen http://www.plain.de
