linux-imx
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committed 157efa8cfa7x
/* * core routines for the asynchronous memory transfer/transform api * * Copyright © 2006, Intel Corporation. * * Dan Williams <dan.j.williams@intel.com> * * with architecture considerations by: * Neil Brown <neilb@suse.de> * Jeff Garzik <jeff@garzik.org> * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License along with * this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. * */static int __init async_tx_init(void){ async_dmaengine_get(); printk(KERN_INFO "async_tx: api initialized (async)\n"); return 0;}static void __exit async_tx_exit(void){ async_dmaengine_put();}module_init(async_tx_init);module_exit(async_tx_exit);/** * __async_tx_find_channel - find a channel to carry out the operation or let * the transaction execute synchronously * @submit: transaction dependency and submission modifiers * @tx_type: transaction type */struct dma_chan *__async_tx_find_channel(struct async_submit_ctl *submit, enum dma_transaction_type tx_type){ struct dma_async_tx_descriptor *depend_tx = submit->depend_tx; /* see if we can keep the chain on one channel */ if (depend_tx && dma_has_cap(tx_type, depend_tx->chan->device->cap_mask)) return depend_tx->chan; return async_dma_find_channel(tx_type);}EXPORT_SYMBOL_GPL(__async_tx_find_channel);/** * async_tx_channel_switch - queue an interrupt descriptor with a dependency * pre-attached. * @depend_tx: the operation that must finish before the new operation runs * @tx: the new operation */static voidasync_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx, struct dma_async_tx_descriptor *tx){ struct dma_chan *chan = depend_tx->chan; struct dma_device *device = chan->device; struct dma_async_tx_descriptor *intr_tx = (void *) ~0; /* first check to see if we can still append to depend_tx */ txd_lock(depend_tx); if (txd_parent(depend_tx) && depend_tx->chan == tx->chan) { txd_chain(depend_tx, tx); intr_tx = NULL; } txd_unlock(depend_tx);