diff options
Diffstat (limited to 'arch/arm/mach-pxa/dma.c')
-rw-r--r-- | arch/arm/mach-pxa/dma.c | 146 |
1 files changed, 0 insertions, 146 deletions
diff --git a/arch/arm/mach-pxa/dma.c b/arch/arm/mach-pxa/dma.c deleted file mode 100644 index 7de17fc5d54..00000000000 --- a/arch/arm/mach-pxa/dma.c +++ /dev/null @@ -1,146 +0,0 @@ -/* - * linux/arch/arm/mach-pxa/dma.c - * - * PXA DMA registration and IRQ dispatching - * - * Author: Nicolas Pitre - * Created: Nov 15, 2001 - * Copyright: MontaVista Software Inc. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - */ - -#include <linux/module.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/interrupt.h> -#include <linux/errno.h> - -#include <asm/system.h> -#include <asm/irq.h> -#include <mach/hardware.h> -#include <mach/dma.h> - -#include <mach/pxa-regs.h> - -struct dma_channel { - char *name; - pxa_dma_prio prio; - void (*irq_handler)(int, void *); - void *data; -}; - -static struct dma_channel *dma_channels; -static int num_dma_channels; - -int pxa_request_dma (char *name, pxa_dma_prio prio, - void (*irq_handler)(int, void *), - void *data) -{ - unsigned long flags; - int i, found = 0; - - /* basic sanity checks */ - if (!name || !irq_handler) - return -EINVAL; - - local_irq_save(flags); - - do { - /* try grabbing a DMA channel with the requested priority */ - for (i = 0; i < num_dma_channels; i++) { - if ((dma_channels[i].prio == prio) && - !dma_channels[i].name) { - found = 1; - break; - } - } - /* if requested prio group is full, try a hier priority */ - } while (!found && prio--); - - if (found) { - DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; - dma_channels[i].name = name; - dma_channels[i].irq_handler = irq_handler; - dma_channels[i].data = data; - } else { - printk (KERN_WARNING "No more available DMA channels for %s\n", name); - i = -ENODEV; - } - - local_irq_restore(flags); - return i; -} - -void pxa_free_dma (int dma_ch) -{ - unsigned long flags; - - if (!dma_channels[dma_ch].name) { - printk (KERN_CRIT - "%s: trying to free channel %d which is already freed\n", - __func__, dma_ch); - return; - } - - local_irq_save(flags); - DCSR(dma_ch) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; - dma_channels[dma_ch].name = NULL; - local_irq_restore(flags); -} - -static irqreturn_t dma_irq_handler(int irq, void *dev_id) -{ - int i, dint = DINT; - - for (i = 0; i < num_dma_channels; i++) { - if (dint & (1 << i)) { - struct dma_channel *channel = &dma_channels[i]; - if (channel->name && channel->irq_handler) { - channel->irq_handler(i, channel->data); - } else { - /* - * IRQ for an unregistered DMA channel: - * let's clear the interrupts and disable it. - */ - printk (KERN_WARNING "spurious IRQ for DMA channel %d\n", i); - DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; - } - } - } - return IRQ_HANDLED; -} - -int __init pxa_init_dma(int num_ch) -{ - int i, ret; - - dma_channels = kzalloc(sizeof(struct dma_channel) * num_ch, GFP_KERNEL); - if (dma_channels == NULL) - return -ENOMEM; - - /* dma channel priorities on pxa2xx processors: - * ch 0 - 3, 16 - 19 <--> (0) DMA_PRIO_HIGH - * ch 4 - 7, 20 - 23 <--> (1) DMA_PRIO_MEDIUM - * ch 8 - 15, 24 - 31 <--> (2) DMA_PRIO_LOW - */ - for (i = 0; i < num_ch; i++) { - DCSR(i) = 0; - dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW); - } - - ret = request_irq(IRQ_DMA, dma_irq_handler, IRQF_DISABLED, "DMA", NULL); - if (ret) { - printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n"); - kfree(dma_channels); - return ret; - } - - num_dma_channels = num_ch; - return 0; -} - -EXPORT_SYMBOL(pxa_request_dma); -EXPORT_SYMBOL(pxa_free_dma); |