On Mon, Sep 13, 2010 at 08:18:08AM -0400, Michael Lawnick wrote: > Datta, Shubhrajyoti said the following: > > > > > >> -----Original Message----- > >> From: Michael Lawnick [mailto:ml.lawnick@xxxxxx] > >> Sent: Monday, September 13, 2010 4:42 PM > >> To: Datta, Shubhrajyoti > >> Cc: lm-sensors@xxxxxxxxxxxxxx > >> Subject: Re: [PATCH v3] hwmon: lm75: Add __devinit and > >> __devexit section initializers > >> > >> Datta, Shubhrajyoti said the following: > >> > > >> > > >> >> -----Original Message----- > >> >> From: Michael Lawnick [mailto:ml.lawnick@xxxxxx] > >> >> Sent: Monday, September 13, 2010 2:52 PM > >> >> To: Datta, Shubhrajyoti > >> >> Cc: lm-sensors@xxxxxxxxxxxxxx > >> >> Subject: Re: [PATCH v3] hwmon: lm75: Add __devinit and > >> >> __devexit section initializers > >> >> > >> >> Shubhrajyoti D said the following: > >> >> ... > >> >> > >> >> > -static int > >> >> > +static int __devinit > >> >> > lm75_probe(struct i2c_client *client, const struct i2c_device_id > >> *id) > >> >> Are you sure? > >> >> If I understand correctly, this function will be thrown away after > >> >> system/module init. But what's about devices that are added later? > >> >> I would expect them to crash on init... > >> > As all of these are I2C devices are I2C I thought it makes sense. > >> > Are you aware of devices that can be plugged/wired runtime? > >> > >> Almost all if behind a multiplexer ;-) > > I missed this part. > There even exist multiplexer that check the bus state and allow > connection only within stop<->start phases. > > > >> There is just some care in synchronization needed. > >> We are currently working with such a system that dynamically adds buses > >> and drops them again (triggered by hotplug). > > Does it mean that all the existing drivers need to adapt. > > I expect them to get adapted step by step when/if this really becomes an > issue. Maybe someday a general cleanup will necessary (and done). Anyway > this might be already an issue for hot plugged cards (e.g. a compact PCI > TV card) that has a local i2c adapter on and common devices on its local > bus. But either this scenario does not exist in practical life or was > fixed by a local code fix. > This is an interesting use case. I didn't think about it either. Looking through other drivers, it seems to be common that __devinit and __devexit are used only if the device is known to be static. Some even make a destinction based on the interface type (eg lm78). As such, it may be better not to apply this patch. Guenter _______________________________________________ lm-sensors mailing list lm-sensors@xxxxxxxxxxxxxx http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
