[ARM] dma: rejig DMA initialization
Rather than having the central DMA multiplexer call the architecture
specific DMA initialization function, have each architecture DMA
initialization function use core_initcall(), and register each DMA
channel separately with the multiplexer.
This removes the array of dma structures in the central multiplexer,
replacing it with an array of pointers instead; this is more flexible
since it allows the drivers to wrap the DMA structure (eventually
allowing us to transition non-ISA DMA drivers away.)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/mach/dma.h b/arch/arm/include/asm/mach/dma.h
index 281ae7e..38a3693 100644
--- a/arch/arm/include/asm/mach/dma.h
+++ b/arch/arm/include/asm/mach/dma.h
@@ -48,10 +48,12 @@
struct dma_ops *d_ops;
};
-/* Prototype: void arch_dma_init(dma)
- * Purpose : Initialise architecture specific DMA
- * Params : dma - pointer to array of DMA structures
+/*
+ * isa_dma_add - add an ISA-style DMA channel
*/
-extern void arch_dma_init(dma_t *dma);
+extern int isa_dma_add(unsigned int, dma_t *dma);
-extern void isa_init_dma(dma_t *dma);
+/*
+ * Add the ISA DMA controller. Always takes channels 0-7.
+ */
+extern void isa_init_dma(void);
diff --git a/arch/arm/kernel/dma-isa.c b/arch/arm/kernel/dma-isa.c
index 29eca48..da02a7f 100644
--- a/arch/arm/kernel/dma-isa.c
+++ b/arch/arm/kernel/dma-isa.c
@@ -160,7 +160,12 @@
.end = 0x048f
} };
-void __init isa_init_dma(dma_t *dma)
+static dma_t isa_dma[8];
+
+/*
+ * ISA DMA always starts at channel 0
+ */
+void __init isa_init_dma(void)
{
/*
* Try to autodetect presence of an ISA DMA controller.
@@ -178,10 +183,10 @@
outb(0xaa, 0x00);
if (inb(0) == 0x55 && inb(0) == 0xaa) {
- int chan, i;
+ unsigned int chan, i;
for (chan = 0; chan < 8; chan++) {
- dma[chan].d_ops = &isa_dma_ops;
+ isa_dma[chan].d_ops = &isa_dma_ops;
isa_disable_dma(chan, NULL);
}
@@ -217,5 +222,12 @@
for (i = 0; i < ARRAY_SIZE(dma_resources); i++)
request_resource(&ioport_resource, dma_resources + i);
+
+ for (chan = 0; chan < 8; chan++) {
+ int ret = isa_dma_add(chan, &isa_dma[chan]);
+ if (ret)
+ printk(KERN_ERR "ISADMA%u: unable to register: %d\n",
+ chan, ret);
+ }
}
}
diff --git a/arch/arm/kernel/dma.c b/arch/arm/kernel/dma.c
index 0ffea3f..aab24f0 100644
--- a/arch/arm/kernel/dma.c
+++ b/arch/arm/kernel/dma.c
@@ -23,16 +23,24 @@
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)
{
- dma_t *dma = dma_chan + chan;
-
- if (chan >= MAX_DMA_CHANNELS || !dma->d_ops)
+ if (chan >= MAX_DMA_CHANNELS)
return NULL;
- return dma;
+ return dma_chan[chan];
+}
+
+int __init isa_dma_add(unsigned int chan, dma_t *dma)
+{
+ if (!dma->d_ops)
+ return -EINVAL;
+ if (dma_chan[chan])
+ return -EBUSY;
+ dma_chan[chan] = dma;
+ return 0;
}
/*
@@ -252,10 +260,3 @@
return ret;
}
EXPORT_SYMBOL(get_dma_residue);
-
-static int __init init_dma(void)
-{
- arch_dma_init(dma_chan);
- return 0;
-}
-core_initcall(init_dma);
diff --git a/arch/arm/mach-footbridge/dma.c b/arch/arm/mach-footbridge/dma.c
index e7b8a6a..fdd94b1 100644
--- a/arch/arm/mach-footbridge/dma.c
+++ b/arch/arm/mach-footbridge/dma.c
@@ -41,7 +41,7 @@
};
#endif
-void __init arch_dma_init(dma_t *dma)
+static int __init fb_dma_init(void)
{
#if 0
dma[_DC21285_DMA(0)].d_ops = &fb_dma_ops;
@@ -49,6 +49,8 @@
#endif
#ifdef CONFIG_ISA_DMA
if (footbridge_cfn_mode())
- isa_init_dma(dma + _ISA_DMA(0));
+ isa_init_dma();
#endif
+ return 0;
}
+core_initcall(fb_dma_init);
diff --git a/arch/arm/mach-rpc/dma.c b/arch/arm/mach-rpc/dma.c
index a86d3ed..efcf671 100644
--- a/arch/arm/mach-rpc/dma.c
+++ b/arch/arm/mach-rpc/dma.c
@@ -302,8 +302,22 @@
.disable = sound_enable_disable_dma,
};
-void __init arch_dma_init(dma_t *dma)
+static dma_t iomd_dma[6];
+
+static dma_t floppy_dma = {
+ .dma_irq = FIQ_FLOPPYDATA,
+ .d_ops = &floppy_dma_ops,
+};
+
+static dma_t sound_dma = {
+ .d_ops = &sound_dma_ops,
+};
+
+static int __init rpc_dma_init(void)
{
+ unsigned int i;
+ int ret;
+
iomd_writeb(0, IOMD_IO0CR);
iomd_writeb(0, IOMD_IO1CR);
iomd_writeb(0, IOMD_IO2CR);
@@ -311,31 +325,39 @@
iomd_writeb(0xa0, IOMD_DMATCR);
- dma[DMA_0].dma_base = IOMD_IO0CURA;
- dma[DMA_0].dma_irq = IRQ_DMA0;
- dma[DMA_0].d_ops = &iomd_dma_ops;
- dma[DMA_1].dma_base = IOMD_IO1CURA;
- dma[DMA_1].dma_irq = IRQ_DMA1;
- dma[DMA_1].d_ops = &iomd_dma_ops;
- dma[DMA_2].dma_base = IOMD_IO2CURA;
- dma[DMA_2].dma_irq = IRQ_DMA2;
- dma[DMA_2].d_ops = &iomd_dma_ops;
- dma[DMA_3].dma_base = IOMD_IO3CURA;
- dma[DMA_3].dma_irq = IRQ_DMA3;
- dma[DMA_3].d_ops = &iomd_dma_ops;
- dma[DMA_S0].dma_base = IOMD_SD0CURA;
- dma[DMA_S0].dma_irq = IRQ_DMAS0;
- dma[DMA_S0].d_ops = &iomd_dma_ops;
- dma[DMA_S1].dma_base = IOMD_SD1CURA;
- dma[DMA_S1].dma_irq = IRQ_DMAS1;
- dma[DMA_S1].d_ops = &iomd_dma_ops;
- dma[DMA_VIRTUAL_FLOPPY].dma_irq = FIQ_FLOPPYDATA;
- dma[DMA_VIRTUAL_FLOPPY].d_ops = &floppy_dma_ops;
- dma[DMA_VIRTUAL_SOUND].d_ops = &sound_dma_ops;
-
/*
* Setup DMA channels 2,3 to be for podules
* and channels 0,1 for internal devices
*/
iomd_writeb(DMA_EXT_IO3|DMA_EXT_IO2, IOMD_DMAEXT);
+
+ iomd_dma[DMA_0].dma_base = IOMD_IO0CURA;
+ iomd_dma[DMA_0].dma_irq = IRQ_DMA0;
+ iomd_dma[DMA_1].dma_base = IOMD_IO1CURA;
+ iomd_dma[DMA_1].dma_irq = IRQ_DMA1;
+ iomd_dma[DMA_2].dma_base = IOMD_IO2CURA;
+ iomd_dma[DMA_2].dma_irq = IRQ_DMA2;
+ iomd_dma[DMA_3].dma_base = IOMD_IO3CURA;
+ iomd_dma[DMA_3].dma_irq = IRQ_DMA3;
+ iomd_dma[DMA_S0].dma_base = IOMD_SD0CURA;
+ iomd_dma[DMA_S0].dma_irq = IRQ_DMAS0;
+ iomd_dma[DMA_S1].dma_base = IOMD_SD1CURA;
+ iomd_dma[DMA_S1].dma_irq = IRQ_DMAS1;
+
+ for (i = DMA_0; i <= DMA_S1; i++) {
+ iomd_dma[i].d_ops = &iomd_dma_ops;
+
+ ret = isa_dma_add(i, &iomd_dma[i]);
+ if (ret)
+ printk("IOMDDMA%u: unable to register: %d\n", i, ret);
+ }
+
+ ret = isa_dma_add(DMA_VIRTUAL_FLOPPY, &floppy_dma);
+ if (ret)
+ printk("IOMDFLOPPY: unable to register: %d\n", ret);
+ ret = isa_dma_add(DMA_VIRTUAL_SOUND, &sound_dma);
+ if (ret)
+ printk("IOMDSOUND: unable to register: %d\n", ret);
+ return 0;
}
+core_initcall(rpc_dma_init);
diff --git a/arch/arm/mach-shark/dma.c b/arch/arm/mach-shark/dma.c
index 6774b8d..10b5b8b 100644
--- a/arch/arm/mach-shark/dma.c
+++ b/arch/arm/mach-shark/dma.c
@@ -13,9 +13,11 @@
#include <asm/dma.h>
#include <asm/mach/dma.h>
-void __init arch_dma_init(dma_t *dma)
+static int __init shark_dma_init(void)
{
#ifdef CONFIG_ISA_DMA
- isa_init_dma(dma);
+ isa_init_dma();
#endif
+ return 0;
}
+core_initcall(shark_dma_init);