dmaengine: omap-dma: provide a hook to get the underlying DMA platform ops

Provide and use a hook to obtain the underlying DMA platform operations
so that omap-dma.c can access the hardware more directly without
involving the legacy DMA driver.
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/plat-omap/dma.c

@@ -2000,6 +2000,12 @@ void omap_dma_global_context_restore(void)
 			omap_clear_dma(ch);
 }
 
+struct omap_system_dma_plat_info *omap_get_plat_info(void)
+{
+	return p;
+}
+EXPORT_SYMBOL_GPL(omap_get_plat_info);
+
 static int omap_system_dma_probe(struct platform_device *pdev)
 {
 	int ch, ret = 0;

drivers/dma/omap-dma.c

@@ -26,11 +26,13 @@ struct omap_dmadev {
 	spinlock_t lock;
 	struct tasklet_struct task;
 	struct list_head pending;
+	struct omap_system_dma_plat_info *plat;
 };
 
 struct omap_chan {
 	struct virt_dma_chan vc;
 	struct list_head node;
+	struct omap_system_dma_plat_info *plat;
 
 	struct dma_slave_config	cfg;
 	unsigned dma_sig;
@@ -573,6 +575,7 @@ static int omap_dma_chan_init(struct omap_dmadev *od, int dma_sig)
 	if (!c)
 		return -ENOMEM;
 
+	c->plat = od->plat;
 	c->dma_sig = dma_sig;
 	c->vc.desc_free = omap_dma_desc_free;
 	vchan_init(&c->vc, &od->ddev);
@@ -605,6 +608,10 @@ static int omap_dma_probe(struct platform_device *pdev)
 	if (!od)
 		return -ENOMEM;
 
+	od->plat = omap_get_plat_info();
+	if (!od->plat)
+		return -EPROBE_DEFER;
+
 	dma_cap_set(DMA_SLAVE, od->ddev.cap_mask);
 	dma_cap_set(DMA_CYCLIC, od->ddev.cap_mask);
 	od->ddev.device_alloc_chan_resources = omap_dma_alloc_chan_resources;

include/linux/omap-dma.h

@@ -292,6 +292,8 @@ struct omap_system_dma_plat_info {
 #define dma_omap15xx()	((dma_omap1() && (d->dev_caps & ENABLE_1510_MODE)))
 #define dma_omap16xx()	((dma_omap1() && (d->dev_caps & ENABLE_16XX_MODE)))
 
+extern struct omap_system_dma_plat_info *omap_get_plat_info(void);
+
 extern void omap_set_dma_priority(int lch, int dst_port, int priority);
 extern int omap_request_dma(int dev_id, const char *dev_name,
 			void (*callback)(int lch, u16 ch_status, void *data),