On Tue, Aug 13, 2013 at 09:42:27PM +0300, Pantelis Antoniou wrote: > But creation just crashes. > > > root@beaglebone:/sys/bus/platform/drivers/omap_i2c# echo 4819c000.i2c >bind > > [ 145.053929] Unable to handle kernel NULL pointer dereference at virtual address 00000001 > > [ 145.062651] pgd = ca8c0000 > > [ 145.065507] [00000001] *pgd=8f437831, *pte=00000000, *ppte=00000000 > > [ 145.072163] Internal error: Oops: 17 [#1] SMP ARM > > [ 145.077105] Modules linked in: ipv6 autofs4 > > [ 145.081537] CPU: 0 PID: 301 Comm: sh Not tainted 3.11.0-rc5-00125-g3b988fb #146 > > [ 145.089222] task: cf5b5580 ti: cf464000 task.ti: cf464000 > > [ 145.094918] PC is at omap_i2c_runtime_suspend+0x10/0xb4 > > [ 145.100408] LR is at omap_i2c_runtime_suspend+0x8/0xb4 Well then, what you have here is a bug in the way that OMAP re-uses the platform device stuff - and that _does_ need fixing somehow. The problem is that i2c_dev->regs is NULL at the point where pm_runtime_set_autosuspend_delay() is called, which as autosuspend is still set from the time that the device was unbound, it means that this triggers an immediate suspend. I suspect that: pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(dev->dev); should be moved later in the probe function, after the switch (scheme) block. -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html