On 06/10/15 10:32, Arnd Bergmann wrote: > On Monday 05 October 2015 13:10:07 Jon Hunter wrote: >> Add support for the Tegra210 Audio DMA controller that is used for >> transferring data between system memory and the Audio sub-system. >> The driver only supports cyclic transfers because this is being solely >> used for audio. >> >> This driver is based upon the work by Dara Ramesh <[email protected]>. >> >> Signed-off-by: Jon Hunter <[email protected]> > > This version looks much better! > > Just one small comment: > >> + slave_req = dma_spec->args[0]; >> + slave_dir = dma_spec->args[1]; >> + >> + if (slave_req == 0) >> + return NULL; >> + >> + switch (slave_dir) { >> + case ADMA_AHUB_TO_MEM: >> + if (slave_req > tdma->rx_requests) >> + return NULL; >> + >> + if (tdma->rx_requests_reserved & BIT(slave_req)) >> + return NULL; >> + >> + tdma->rx_requests_reserved |= BIT(slave_req); >> + break; > > The rx_requests_reserved logic looks racy, if you have more than > one concurrent request or release. Better use atomic_test_and_set() > here and turn the variable into an atomic_t.
Ah yes, will update. Thanks Jon -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
