hi everyone,
i am a beginner level in driver programming. please help to solve this
problem.
this is a part of the internal modem driver coding. this is for intel chip
set internal modem.
-------------------------------------------------------------------------------------------------------------------------------------------------------------
// ZT_MAX_CHUNKSIZE = 8
wc->writechunk = (int *)pci_alloc_consistent(pdev, ZT_MAX_CHUNKSIZE * 2 * 2
* 2 * 4, &wc->writedma);
if (!wc->writechunk) {
printk("wcfxo: Unable to allocate DMA-able memory\n");
if (wc->freeregion)
release_region(wc->ioaddr, 0xff);
return -ENOMEM;
}
wc->readchunk = wc->writechunk + ZT_MAX_CHUNKSIZE * 4; /* in
doublewords */
wc->readdma = wc->writedma + ZT_MAX_CHUNKSIZE * 16; /* in bytes
*/
---------------------------------------------------------------------------------------------------------------------------------------------------------------
here they are creating 2 chunks for writing and reading.
but i couldn't understand this line.
wc->readdma = wc->writedma + ZT_MAX_CHUNKSIZE * 16;
why are they using ZT_MAX_CHUNKSIZE * 16 for allocating read chunk?
-jeyram
