Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/arm/mach-pxa/dma.c b/arch/arm/mach-pxa/dma.c
new file mode 100644
index 0000000..458112b
--- /dev/null
+++ b/arch/arm/mach-pxa/dma.c
@@ -0,0 +1,133 @@
+/*
+ * 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 <asm/hardware.h>
+#include <asm/dma.h>
+
+#include <asm/arch/pxa-regs.h>
+
+static struct dma_channel {
+ char *name;
+ void (*irq_handler)(int, void *, struct pt_regs *);
+ void *data;
+} dma_channels[PXA_DMA_CHANNELS];
+
+
+int pxa_request_dma (char *name, pxa_dma_prio prio,
+ void (*irq_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 + PXA_DMA_NBCH(prio); 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) {
+ 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",
+ __FUNCTION__, 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, struct pt_regs *regs)
+{
+ int i, dint = DINT;
+
+ for (i = 0; i < PXA_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, 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);
+ DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
+ }
+ }
+ }
+ return IRQ_HANDLED;
+}
+
+static int __init pxa_dma_init (void)
+{
+ int ret;
+
+ ret = request_irq (IRQ_DMA, dma_irq_handler, 0, "DMA", NULL);
+ if (ret)
+ printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n");
+ return ret;
+}
+
+arch_initcall(pxa_dma_init);
+
+EXPORT_SYMBOL(pxa_request_dma);
+EXPORT_SYMBOL(pxa_free_dma);
+