diff options
Diffstat (limited to 'arch/arm/mach-imx/dma.c')
| -rw-r--r-- | arch/arm/mach-imx/dma.c | 203 |
1 files changed, 0 insertions, 203 deletions
diff --git a/arch/arm/mach-imx/dma.c b/arch/arm/mach-imx/dma.c deleted file mode 100644 index 71a59e19616..00000000000 --- a/arch/arm/mach-imx/dma.c +++ /dev/null @@ -1,203 +0,0 @@ -/* - * linux/arch/arm/mach-imx/dma.c - * - * imx DMA registration and IRQ dispatching - * - * 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. - * - * 03/03/2004 Sascha Hauer <sascha@saschahauer.de> - * initial version heavily inspired by - * linux/arch/arm/mach-pxa/dma.c - */ - -#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 <asm/hardware.h> -#include <asm/dma.h> - -static struct dma_channel { - char *name; - void (*irq_handler) (int, void *, struct pt_regs *); - void (*err_handler) (int, void *, struct pt_regs *); - void *data; -} dma_channels[11]; - -/* set err_handler to NULL to have the standard info-only error handler */ -int -imx_request_dma(char *name, imx_dma_prio prio, - void (*irq_handler) (int, void *, struct pt_regs *), - void (*err_handler) (int, void *, struct pt_regs *), void *data) -{ - unsigned long flags; - int i, found = 0; - - /* basic sanity checks */ - if (!name || !irq_handler) - return -EINVAL; - - local_irq_save(flags); - - /* try grabbing a DMA channel with the requested priority */ - for (i = prio; i < prio + (prio == DMA_PRIO_LOW) ? 8 : 4; i++) { - if (!dma_channels[i].name) { - found = 1; - break; - } - } - - if (!found) { - /* requested prio group is full, try hier priorities */ - for (i = prio - 1; i >= 0; i--) { - if (!dma_channels[i].name) { - found = 1; - break; - } - } - } - - if (found) { - DIMR &= ~(1 << i); - dma_channels[i].name = name; - dma_channels[i].irq_handler = irq_handler; - dma_channels[i].err_handler = err_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 -imx_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", - __FUNCTION__, dma_ch); - return; - } - - local_irq_save(flags); - DIMR &= ~(1 << dma_ch); - dma_channels[dma_ch].name = NULL; - local_irq_restore(flags); -} - -static irqreturn_t -dma_err_handler(int irq, void *dev_id, struct pt_regs *regs) -{ - int i, disr = DISR; - struct dma_channel *channel; - unsigned int err_mask = DBTOSR | DRTOSR | DSESR | DBOSR; - - DISR = disr; - for (i = 0; i < 11; i++) { - channel = &dma_channels[i]; - - if ( (err_mask & 1<<i) && channel->name && channel->err_handler) { - channel->err_handler(i, channel->data, regs); - continue; - } - - if (DBTOSR & (1 << i)) { - printk(KERN_WARNING - "Burst timeout on channel %d (%s)\n", - i, channel->name); - DBTOSR |= (1 << i); - } - if (DRTOSR & (1 << i)) { - printk(KERN_WARNING - "Request timeout on channel %d (%s)\n", - i, channel->name); - DRTOSR |= (1 << i); - } - if (DSESR & (1 << i)) { - printk(KERN_WARNING - "Transfer timeout on channel %d (%s)\n", - i, channel->name); - DSESR |= (1 << i); - } - if (DBOSR & (1 << i)) { - printk(KERN_WARNING - "Buffer overflow timeout on channel %d (%s)\n", - i, channel->name); - DBOSR |= (1 << i); - } - } - return IRQ_HANDLED; -} - -static irqreturn_t -dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs) -{ - int i, disr = DISR; - - DISR = disr; - for (i = 0; i < 11; i++) { - if (disr & (1 << i)) { - struct dma_channel *channel = &dma_channels[i]; - if (channel->name && channel->irq_handler) { - channel->irq_handler(i, channel->data, regs); - } 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); - } - } - } - return IRQ_HANDLED; -} - -static int __init -imx_dma_init(void) -{ - int ret; - - /* reset DMA module */ - DCR = DCR_DRST; - - ret = request_irq(DMA_INT, dma_irq_handler, 0, "DMA", NULL); - if (ret) { - printk(KERN_CRIT "Wow! Can't register IRQ for DMA\n"); - return ret; - } - - ret = request_irq(DMA_ERR, dma_err_handler, 0, "DMA", NULL); - if (ret) { - printk(KERN_CRIT "Wow! Can't register ERRIRQ for DMA\n"); - free_irq(DMA_INT, NULL); - } - - /* enable DMA module */ - DCR = DCR_DEN; - - /* clear all interrupts */ - DISR = 0x3ff; - - /* enable interrupts */ - DIMR = 0; - - return ret; -} - -arch_initcall(imx_dma_init); - -EXPORT_SYMBOL(imx_request_dma); -EXPORT_SYMBOL(imx_free_dma); |