diff options
Diffstat (limited to 'arch/arm/kernel/dma.c')
-rw-r--r-- | arch/arm/kernel/dma.c | 119 |
1 files changed, 67 insertions, 52 deletions
diff --git a/arch/arm/kernel/dma.c b/arch/arm/kernel/dma.c index d006085..7d5b9fb 100644 --- a/arch/arm/kernel/dma.c +++ b/arch/arm/kernel/dma.c @@ -15,6 +15,7 @@ #include <linux/init.h> #include <linux/spinlock.h> #include <linux/errno.h> +#include <linux/scatterlist.h> #include <asm/dma.h> @@ -23,19 +24,40 @@ DEFINE_SPINLOCK(dma_spin_lock); EXPORT_SYMBOL(dma_spin_lock); -static dma_t dma_chan[MAX_DMA_CHANNELS]; +static dma_t *dma_chan[MAX_DMA_CHANNELS]; + +static inline dma_t *dma_channel(unsigned int chan) +{ + if (chan >= MAX_DMA_CHANNELS) + return NULL; + + return dma_chan[chan]; +} + +int __init isa_dma_add(unsigned int chan, dma_t *dma) +{ + if (!dma->d_ops) + return -EINVAL; + + sg_init_table(&dma->buf, 1); + + if (dma_chan[chan]) + return -EBUSY; + dma_chan[chan] = dma; + return 0; +} /* * Request DMA channel * * On certain platforms, we have to allocate an interrupt as well... */ -int request_dma(dmach_t channel, const char *device_id) +int request_dma(unsigned int chan, const char *device_id) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); int ret; - if (channel >= MAX_DMA_CHANNELS || !dma->d_ops) + if (!dma) goto bad_dma; if (xchg(&dma->lock, 1) != 0) @@ -47,7 +69,7 @@ int request_dma(dmach_t channel, const char *device_id) ret = 0; if (dma->d_ops->request) - ret = dma->d_ops->request(channel, dma); + ret = dma->d_ops->request(chan, dma); if (ret) xchg(&dma->lock, 0); @@ -55,7 +77,7 @@ int request_dma(dmach_t channel, const char *device_id) return ret; bad_dma: - printk(KERN_ERR "dma: trying to allocate DMA%d\n", channel); + printk(KERN_ERR "dma: trying to allocate DMA%d\n", chan); return -EINVAL; busy: @@ -68,42 +90,42 @@ EXPORT_SYMBOL(request_dma); * * On certain platforms, we have to free interrupt as well... */ -void free_dma(dmach_t channel) +void free_dma(unsigned int chan) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); - if (channel >= MAX_DMA_CHANNELS || !dma->d_ops) + if (!dma) goto bad_dma; if (dma->active) { - printk(KERN_ERR "dma%d: freeing active DMA\n", channel); - dma->d_ops->disable(channel, dma); + printk(KERN_ERR "dma%d: freeing active DMA\n", chan); + dma->d_ops->disable(chan, dma); dma->active = 0; } if (xchg(&dma->lock, 0) != 0) { if (dma->d_ops->free) - dma->d_ops->free(channel, dma); + dma->d_ops->free(chan, dma); return; } - printk(KERN_ERR "dma%d: trying to free free DMA\n", channel); + printk(KERN_ERR "dma%d: trying to free free DMA\n", chan); return; bad_dma: - printk(KERN_ERR "dma: trying to free DMA%d\n", channel); + printk(KERN_ERR "dma: trying to free DMA%d\n", chan); } EXPORT_SYMBOL(free_dma); /* Set DMA Scatter-Gather list */ -void set_dma_sg (dmach_t channel, struct scatterlist *sg, int nr_sg) +void set_dma_sg (unsigned int chan, struct scatterlist *sg, int nr_sg) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (dma->active) printk(KERN_ERR "dma%d: altering DMA SG while " - "DMA active\n", channel); + "DMA active\n", chan); dma->sg = sg; dma->sgcount = nr_sg; @@ -115,13 +137,13 @@ EXPORT_SYMBOL(set_dma_sg); * * Copy address to the structure, and set the invalid bit */ -void __set_dma_addr (dmach_t channel, void *addr) +void __set_dma_addr (unsigned int chan, void *addr) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (dma->active) printk(KERN_ERR "dma%d: altering DMA address while " - "DMA active\n", channel); + "DMA active\n", chan); dma->sg = NULL; dma->addr = addr; @@ -133,13 +155,13 @@ EXPORT_SYMBOL(__set_dma_addr); * * Copy address to the structure, and set the invalid bit */ -void set_dma_count (dmach_t channel, unsigned long count) +void set_dma_count (unsigned int chan, unsigned long count) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (dma->active) printk(KERN_ERR "dma%d: altering DMA count while " - "DMA active\n", channel); + "DMA active\n", chan); dma->sg = NULL; dma->count = count; @@ -149,13 +171,13 @@ EXPORT_SYMBOL(set_dma_count); /* Set DMA direction mode */ -void set_dma_mode (dmach_t channel, dmamode_t mode) +void set_dma_mode (unsigned int chan, unsigned int mode) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (dma->active) printk(KERN_ERR "dma%d: altering DMA mode while " - "DMA active\n", channel); + "DMA active\n", chan); dma->dma_mode = mode; dma->invalid = 1; @@ -164,42 +186,42 @@ EXPORT_SYMBOL(set_dma_mode); /* Enable DMA channel */ -void enable_dma (dmach_t channel) +void enable_dma (unsigned int chan) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (!dma->lock) goto free_dma; if (dma->active == 0) { dma->active = 1; - dma->d_ops->enable(channel, dma); + dma->d_ops->enable(chan, dma); } return; free_dma: - printk(KERN_ERR "dma%d: trying to enable free DMA\n", channel); + printk(KERN_ERR "dma%d: trying to enable free DMA\n", chan); BUG(); } EXPORT_SYMBOL(enable_dma); /* Disable DMA channel */ -void disable_dma (dmach_t channel) +void disable_dma (unsigned int chan) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); if (!dma->lock) goto free_dma; if (dma->active == 1) { dma->active = 0; - dma->d_ops->disable(channel, dma); + dma->d_ops->disable(chan, dma); } return; free_dma: - printk(KERN_ERR "dma%d: trying to disable free DMA\n", channel); + printk(KERN_ERR "dma%d: trying to disable free DMA\n", chan); BUG(); } EXPORT_SYMBOL(disable_dma); @@ -207,45 +229,38 @@ EXPORT_SYMBOL(disable_dma); /* * Is the specified DMA channel active? */ -int dma_channel_active(dmach_t channel) +int dma_channel_active(unsigned int chan) { - return dma_chan[channel].active; + dma_t *dma = dma_channel(chan); + return dma->active; } EXPORT_SYMBOL(dma_channel_active); -void set_dma_page(dmach_t channel, char pagenr) +void set_dma_page(unsigned int chan, char pagenr) { - printk(KERN_ERR "dma%d: trying to set_dma_page\n", channel); + printk(KERN_ERR "dma%d: trying to set_dma_page\n", chan); } EXPORT_SYMBOL(set_dma_page); -void set_dma_speed(dmach_t channel, int cycle_ns) +void set_dma_speed(unsigned int chan, int cycle_ns) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); int ret = 0; if (dma->d_ops->setspeed) - ret = dma->d_ops->setspeed(channel, dma, cycle_ns); + ret = dma->d_ops->setspeed(chan, dma, cycle_ns); dma->speed = ret; } EXPORT_SYMBOL(set_dma_speed); -int get_dma_residue(dmach_t channel) +int get_dma_residue(unsigned int chan) { - dma_t *dma = dma_chan + channel; + dma_t *dma = dma_channel(chan); int ret = 0; if (dma->d_ops->residue) - ret = dma->d_ops->residue(channel, dma); + ret = dma->d_ops->residue(chan, dma); return ret; } EXPORT_SYMBOL(get_dma_residue); - -static int __init init_dma(void) -{ - arch_dma_init(dma_chan); - return 0; -} - -core_initcall(init_dma); |