* Pandita, Vikram <[email protected]> [091117 09:50]: > Paul > > >-----Original Message----- > >From: [email protected] > >[mailto:[email protected]] On Behalf Of Paul > >Walmsley > >Sent: Tuesday, November 17, 2009 11:39 AM > >To: Russell King - ARM Linux > >Cc: [email protected]; Juha Leppänen; > >[email protected] > >Subject: Re: [PATCH 3/3] OMAP clock/hwmod: fix off-by-one errors > <snip> > > > >+/** > >+ * omap_test_timeout - busy-loop, testing a condition > >+ * @cond: condition to test until it evaluates to true > >+ * @timeout: maximum number of microseconds in the timeout > >+ * @index: loop index (integer) > >+ * > >+ * Loop waiting for @cond to become true or until at least @timeout > >+ * microseconds have passed. To use, define some integer @index in the > >+ * calling code. After running, if @index == @timeout, then the loop has > >+ * timed out. > >+ */ > >+#define omap_test_timeout(cond, timeout, index) \ > >+({ \ > >+ for (index = 0; index < timeout; index++) { \ > >+ if (cond) \ > >+ break; \ > >+ udelay(1); \ > >+ } \ > >+}) > >+ > > There is a similar kind of function implemented in USB host, that returns > -ETIMEDOUT > Which makes more sense for failure case. > > Maybe such a generic function for all omaps is needed. > > Refer: > drivers/usb/host/ehci-hcd.c > static int handshake (struct ehci_hcd *ehci, void __iomem *ptr, > u32 mask, u32 done, int usec) > { > u32 result; > > do { > result = ehci_readl(ehci, ptr); > if (result == ~(u32)0) /* card removed */ > return -ENODEV; > result &= mask; > if (result == done) > return 0; > udelay (1); > usec--; > } while (usec > 0); > return -ETIMEDOUT; > } > > > > #endif /* __ARCH_ARM_MACH_OMAP_COMMON_H */
Well we need to stick to minimal changes if we plan to send this in as a fix. Anything more complex we should do the next merge window. Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
