On Tue, Nov 20, 2012 at 12:41:03PM +0100, Marc Kleine-Budde wrote: > On 11/20/2012 02:33 AM, Peter Chen wrote: > > On Mon, Nov 19, 2012 at 05:05:16PM +0100, Marc Kleine-Budde wrote: > >>> +int ci_hdrc_otg_init(struct ci13xxx *ci) > >>> +{ > >>> + /* Useless at current */ > >>> + ci->otg.set_peripheral = ci_otg_set_peripheral; > >>> + ci->otg.set_host = ci_otg_set_host; > >>> + if (!IS_ERR_OR_NULL(ci->transceiver)) > >> ^^^^^^^^^^^^^^ > >> > >> Is considered harmful by some people. Can we test against NULL here? > > > > Any stories that it is harmful? > > Your use-case isn't but there others are: > http://www.mail-archive.com/linux-omap@xxxxxxxxxxxxxxx/msg78030.html Thanks, marc. It said below code is error if the foo is really null. if (IS_ERR_OR_NULL(foo)) return PTR_ERR(foo); For this case, the ci->transceiver may be null or errno pointer, it needs IS_ERR_OR_NULL. > > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Industrial Linux Solutions | Phone: +49-231-2826-924 | > Vertretung West/Dortmund | Fax: +49-5121-206917-5555 | > Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de | > -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html