X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fsh%2Fdrivers%2Fdma%2Fdma-api.c;h=3fc34e1cf7dfdb2bad07cb207eee40c2d7176bdc;hb=9bf4aaab3e101692164d49b7ca357651eb691cb6;hp=f8b352d4b091a3e9cbb095d5ad5947a61dde78f1;hpb=db216c3d5e4c040e557a50f8f5d35d5c415e8c1c;p=linux-2.6.git diff --git a/arch/sh/drivers/dma/dma-api.c b/arch/sh/drivers/dma/dma-api.c index f8b352d4b..3fc34e1cf 100644 --- a/arch/sh/drivers/dma/dma-api.c +++ b/arch/sh/drivers/dma/dma-api.c @@ -3,23 +3,24 @@ * * SuperH-specific DMA management API * - * Copyright (C) 2003 Paul Mundt + * Copyright (C) 2003, 2004 Paul Mundt * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. - */ + */ #include #include #include #include #include +#include #include -struct dma_info dma_info[MAX_DMA_CHANNELS] = { { 0, } }; spinlock_t dma_spin_lock = SPIN_LOCK_UNLOCKED; +static LIST_HEAD(registered_dmac_list); -/* +/* * A brief note about the reasons for this API as it stands. * * For starters, the old ISA DMA API didn't work for us for a number of @@ -54,124 +55,213 @@ spinlock_t dma_spin_lock = SPIN_LOCK_UNLOCKED; struct dma_info *get_dma_info(unsigned int chan) { - return dma_info + chan; + struct list_head *pos, *tmp; + unsigned int total = 0; + + /* + * Look for each DMAC's range to determine who the owner of + * the channel is. + */ + list_for_each_safe(pos, tmp, ®istered_dmac_list) { + struct dma_info *info = list_entry(pos, struct dma_info, list); + + total += info->nr_channels; + if (chan > total) + continue; + + return info; + } + + return NULL; +} + +struct dma_channel *get_dma_channel(unsigned int chan) +{ + struct dma_info *info = get_dma_info(chan); + + if (!info) + return ERR_PTR(-EINVAL); + + return info->channels + chan; } int get_dma_residue(unsigned int chan) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; if (info->ops->get_residue) - return info->ops->get_residue(info); - + return info->ops->get_residue(channel); + return 0; } int request_dma(unsigned int chan, const char *dev_id) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; - down(&info->sem); + down(&channel->sem); if (!info->ops || chan >= MAX_DMA_CHANNELS) { - up(&info->sem); + up(&channel->sem); return -EINVAL; } - - atomic_set(&info->busy, 1); - info->dev_id = dev_id; + atomic_set(&channel->busy, 1); - up(&info->sem); + strlcpy(channel->dev_id, dev_id, sizeof(channel->dev_id)); + + up(&channel->sem); if (info->ops->request) - return info->ops->request(info); - + return info->ops->request(channel); + return 0; } void free_dma(unsigned int chan) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; if (info->ops->free) - info->ops->free(info); - - atomic_set(&info->busy, 0); + info->ops->free(channel); + + atomic_set(&channel->busy, 0); } void dma_wait_for_completion(unsigned int chan) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; - if (info->tei_capable) { - wait_event(info->wait_queue, (info->ops->get_residue(info) == 0)); + if (channel->flags & DMA_TEI_CAPABLE) { + wait_event(channel->wait_queue, + (info->ops->get_residue(channel) == 0)); return; } - while (info->ops->get_residue(info)) + while (info->ops->get_residue(channel)) cpu_relax(); } void dma_configure_channel(unsigned int chan, unsigned long flags) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; if (info->ops->configure) - info->ops->configure(info, flags); + info->ops->configure(channel, flags); } int dma_xfer(unsigned int chan, unsigned long from, unsigned long to, size_t size, unsigned int mode) { struct dma_info *info = get_dma_info(chan); + struct dma_channel *channel = &info->channels[chan]; - info->sar = from; - info->dar = to; - info->count = size; - info->mode = mode; + channel->sar = from; + channel->dar = to; + channel->count = size; + channel->mode = mode; - return info->ops->xfer(info); + return info->ops->xfer(channel); } #ifdef CONFIG_PROC_FS static int dma_read_proc(char *buf, char **start, off_t off, int len, int *eof, void *data) { - struct dma_info *info; + struct list_head *pos, *tmp; char *p = buf; - int i; - for (i = 0, info = dma_info; i < MAX_DMA_CHANNELS; i++, info++) { - if (!atomic_read(&info->busy)) - continue; + if (list_empty(®istered_dmac_list)) + return 0; + + /* + * Iterate over each registered DMAC + */ + list_for_each_safe(pos, tmp, ®istered_dmac_list) { + struct dma_info *info = list_entry(pos, struct dma_info, list); + int i; - p += sprintf(p, "%2d: %14s %s\n", i, - info->ops->name, info->dev_id); + /* + * Iterate over each channel + */ + for (i = 0; i < info->nr_channels; i++) { + struct dma_channel *channel = info->channels + i; + + if (!(channel->flags & DMA_CONFIGURED)) + continue; + + p += sprintf(p, "%2d: %14s %s\n", i, + info->name, channel->dev_id); + } } return p - buf; } #endif -int __init register_dmac(struct dma_ops *ops) + +int __init register_dmac(struct dma_info *info) { int i; - printk("DMA: Registering %s handler.\n", ops->name); + INIT_LIST_HEAD(&info->list); + + printk(KERN_INFO "DMA: Registering %s handler (%d channels).\n", + info->name, info->nr_channels); + + BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels); - for (i = 0; i < MAX_DMA_CHANNELS; i++) { - struct dma_info *info = get_dma_info(i); + /* + * Don't touch pre-configured channels + */ + if (!(info->flags & DMAC_CHANNELS_CONFIGURED)) { + unsigned int size; - info->chan = i; + size = sizeof(struct dma_channel) * info->nr_channels; - init_MUTEX(&info->sem); - init_waitqueue_head(&info->wait_queue); + info->channels = kmalloc(size, GFP_KERNEL); + if (!info->channels) + return -ENOMEM; + + memset(info->channels, 0, size); } + for (i = 0; i < info->nr_channels; i++) { + struct dma_channel *chan = info->channels + i; + + chan->chan = i; + + memcpy(chan->dev_id, "Unused", 7); + + if (info->flags & DMAC_CHANNELS_TEI_CAPABLE) + chan->flags |= DMA_TEI_CAPABLE; + + init_MUTEX(&chan->sem); + init_waitqueue_head(&chan->wait_queue); + +#ifdef CONFIG_SYSFS + dma_create_sysfs_files(chan); +#endif + } + + list_add(&info->list, ®istered_dmac_list); + return 0; } +void __exit unregister_dmac(struct dma_info *info) +{ + if (!(info->flags & DMAC_CHANNELS_CONFIGURED)) + kfree(info->channels); + + list_del(&info->list); +} + static int __init dma_api_init(void) { printk("DMA: Registering DMA API.\n"); @@ -191,8 +281,11 @@ MODULE_LICENSE("GPL"); EXPORT_SYMBOL(request_dma); EXPORT_SYMBOL(free_dma); +EXPORT_SYMBOL(register_dmac); +EXPORT_SYMBOL(unregister_dmac); EXPORT_SYMBOL(get_dma_residue); EXPORT_SYMBOL(get_dma_info); +EXPORT_SYMBOL(get_dma_channel); EXPORT_SYMBOL(dma_xfer); EXPORT_SYMBOL(dma_wait_for_completion); EXPORT_SYMBOL(dma_configure_channel);