dmaengine: ste_dma40: Amalgamate DMA source and destination channel numbers

Devices which utilise DMA use the same device numbers for transmitting
and receiving. In this patch we encode the source and destination
information into one single attribute. We can subsequently exploit the
direction attribute to see which of the transfer directions are being
described. This also lessens the burden on platform data.

Cc: Dan Williams <djbw@fb.com>
Cc: Per Forlin <per.forlin@stericsson.com>
Cc: Rabin Vincent <rabin@rab.in>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index d481cb8..63495f6 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -1302,21 +1302,17 @@
 static void d40_config_set_event(struct d40_chan *d40c,
 				 enum d40_events event_type)
 {
+	u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dev_type);
+
 	/* Enable event line connected to device (or memcpy) */
 	if ((d40c->dma_cfg.dir ==  STEDMA40_PERIPH_TO_MEM) ||
-	    (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH)) {
-		u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type);
-
+	    (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH))
 		__d40_config_set_event(d40c, event_type, event,
 				       D40_CHAN_REG_SSLNK);
-	}
 
-	if (d40c->dma_cfg.dir !=  STEDMA40_PERIPH_TO_MEM) {
-		u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
-
+	if (d40c->dma_cfg.dir !=  STEDMA40_PERIPH_TO_MEM)
 		__d40_config_set_event(d40c, event_type, event,
 				       D40_CHAN_REG_SDLNK);
-	}
 }
 
 static u32 d40_chan_has_events(struct d40_chan *d40c)
@@ -1758,8 +1754,6 @@
 			     struct stedma40_chan_cfg *conf)
 {
 	int res = 0;
-	u32 dst_event_group = D40_TYPE_TO_GROUP(conf->dst_dev_type);
-	u32 src_event_group = D40_TYPE_TO_GROUP(conf->src_dev_type);
 	bool is_log = conf->mode == STEDMA40_MODE_LOGICAL;
 
 	if (!conf->dir) {
@@ -1767,44 +1761,26 @@
 		res = -EINVAL;
 	}
 
-	if (conf->dst_dev_type != STEDMA40_DEV_DST_MEMORY &&
-	    d40c->base->plat_data->dev_tx[conf->dst_dev_type] == 0 &&
-	    d40c->runtime_addr == 0) {
-
-		chan_err(d40c, "Invalid TX channel address (%d)\n",
-			 conf->dst_dev_type);
-		res = -EINVAL;
-	}
-
-	if (conf->src_dev_type != STEDMA40_DEV_SRC_MEMORY &&
-	    d40c->base->plat_data->dev_rx[conf->src_dev_type] == 0 &&
-	    d40c->runtime_addr == 0) {
-		chan_err(d40c, "Invalid RX channel address (%d)\n",
-			conf->src_dev_type);
+	if ((is_log && conf->dev_type > d40c->base->num_log_chans)  ||
+	    (!is_log && conf->dev_type > d40c->base->num_phy_chans) ||
+	    (conf->dev_type < 0)) {
+		chan_err(d40c, "Invalid device type (%d)\n", conf->dev_type);
 		res = -EINVAL;
 	}
 
 	if (conf->dir == STEDMA40_MEM_TO_PERIPH &&
-	    conf->dst_dev_type == STEDMA40_DEV_DST_MEMORY) {
-		chan_err(d40c, "Invalid dst\n");
+	    d40c->base->plat_data->dev_tx[conf->dev_type] == 0 &&
+	    d40c->runtime_addr == 0) {
+		chan_err(d40c, "Invalid TX channel address (%d)\n",
+			 conf->dev_type);
 		res = -EINVAL;
 	}
 
 	if (conf->dir == STEDMA40_PERIPH_TO_MEM &&
-	    conf->src_dev_type == STEDMA40_DEV_SRC_MEMORY) {
-		chan_err(d40c, "Invalid src\n");
-		res = -EINVAL;
-	}
-
-	if (conf->src_dev_type == STEDMA40_DEV_SRC_MEMORY &&
-	    conf->dst_dev_type == STEDMA40_DEV_DST_MEMORY && is_log) {
-		chan_err(d40c, "No event line\n");
-		res = -EINVAL;
-	}
-
-	if (conf->dir == STEDMA40_PERIPH_TO_PERIPH &&
-	    (src_event_group != dst_event_group)) {
-		chan_err(d40c, "Invalid event group\n");
+	    d40c->base->plat_data->dev_rx[conf->dev_type] == 0 &&
+	    d40c->runtime_addr == 0) {
+		chan_err(d40c, "Invalid RX channel address (%d)\n",
+			 conf->dev_type);
 		res = -EINVAL;
 	}
 
@@ -1925,7 +1901,7 @@
 
 static int d40_allocate_channel(struct d40_chan *d40c, bool *first_phy_user)
 {
-	int dev_type;
+	int dev_type = d40c->dma_cfg.dev_type;
 	int event_group;
 	int event_line;
 	struct d40_phy_res *phys;
@@ -1940,13 +1916,11 @@
 	num_phy_chans = d40c->base->num_phy_chans;
 
 	if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM) {
-		dev_type = d40c->dma_cfg.src_dev_type;
 		log_num = 2 * dev_type;
 		is_src = true;
 	} else if (d40c->dma_cfg.dir == STEDMA40_MEM_TO_PERIPH ||
 		   d40c->dma_cfg.dir == STEDMA40_MEM_TO_MEM) {
 		/* dst event lines are used for logical memcpy */
-		dev_type = d40c->dma_cfg.dst_dev_type;
 		log_num = 2 * dev_type + 1;
 		is_src = false;
 	} else
@@ -2058,8 +2032,7 @@
 
 	if (dma_has_cap(DMA_MEMCPY, cap) && !dma_has_cap(DMA_SLAVE, cap)) {
 		d40c->dma_cfg = dma40_memcpy_conf_log;
-		d40c->dma_cfg.src_dev_type = STEDMA40_DEV_SRC_MEMORY;
-		d40c->dma_cfg.dst_dev_type = dma40_memcpy_channels[d40c->chan.chan_id];
+		d40c->dma_cfg.dev_type = dma40_memcpy_channels[d40c->chan.chan_id];
 
 	} else if (dma_has_cap(DMA_MEMCPY, cap) &&
 		   dma_has_cap(DMA_SLAVE, cap)) {
@@ -2076,7 +2049,7 @@
 {
 
 	int res = 0;
-	u32 event;
+	u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dev_type);
 	struct d40_phy_res *phy = d40c->phy_chan;
 	bool is_src;
 
@@ -2095,13 +2068,11 @@
 	}
 
 	if (d40c->dma_cfg.dir == STEDMA40_MEM_TO_PERIPH ||
-	    d40c->dma_cfg.dir == STEDMA40_MEM_TO_MEM) {
-		event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
+	    d40c->dma_cfg.dir == STEDMA40_MEM_TO_MEM)
 		is_src = false;
-	} else if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM) {
-		event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type);
+	else if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM)
 		is_src = true;
-	} else {
+	else {
 		chan_err(d40c, "Unknown direction\n");
 		return -EINVAL;
 	}
@@ -2142,7 +2113,7 @@
 	unsigned long flags;
 	void __iomem *active_reg;
 	u32 status;
-	u32 event;
+	u32 event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dev_type);
 
 	spin_lock_irqsave(&d40c->lock, flags);
 
@@ -2163,10 +2134,8 @@
 
 	if (d40c->dma_cfg.dir == STEDMA40_MEM_TO_PERIPH ||
 	    d40c->dma_cfg.dir == STEDMA40_MEM_TO_MEM) {
-		event = D40_TYPE_TO_EVENT(d40c->dma_cfg.dst_dev_type);
 		status = readl(chanbase + D40_CHAN_REG_SDLNK);
 	} else if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM) {
-		event = D40_TYPE_TO_EVENT(d40c->dma_cfg.src_dev_type);
 		status = readl(chanbase + D40_CHAN_REG_SSLNK);
 	} else {
 		chan_err(d40c, "Unknown direction\n");
@@ -2308,9 +2277,9 @@
 		return chan->runtime_addr;
 
 	if (direction == DMA_DEV_TO_MEM)
-		addr = plat->dev_rx[cfg->src_dev_type];
+		addr = plat->dev_rx[cfg->dev_type];
 	else if (direction == DMA_MEM_TO_DEV)
-		addr = plat->dev_tx[cfg->dst_dev_type];
+		addr = plat->dev_tx[cfg->dev_type];
 
 	return addr;
 }
@@ -2441,11 +2410,11 @@
 
 	if ((d40c->dma_cfg.dir ==  STEDMA40_PERIPH_TO_MEM) ||
 	    (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH))
-		__d40_set_prio_rt(d40c, d40c->dma_cfg.src_dev_type, true);
+		__d40_set_prio_rt(d40c, d40c->dma_cfg.dev_type, true);
 
 	if ((d40c->dma_cfg.dir ==  STEDMA40_MEM_TO_PERIPH) ||
 	    (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_PERIPH))
-		__d40_set_prio_rt(d40c, d40c->dma_cfg.dst_dev_type, false);
+		__d40_set_prio_rt(d40c, d40c->dma_cfg.dev_type, false);
 }
 
 /* DMA ENGINE functions */
@@ -2489,10 +2458,10 @@
 
 		if (d40c->dma_cfg.dir == STEDMA40_PERIPH_TO_MEM)
 			d40c->lcpa = d40c->base->lcpa_base +
-				d40c->dma_cfg.src_dev_type * D40_LCPA_CHAN_SIZE;
+				d40c->dma_cfg.dev_type * D40_LCPA_CHAN_SIZE;
 		else
 			d40c->lcpa = d40c->base->lcpa_base +
-				d40c->dma_cfg.dst_dev_type *
+				d40c->dma_cfg.dev_type *
 				D40_LCPA_CHAN_SIZE + D40_LCPA_CHAN_DST_DELTA;
 	}
 
@@ -2755,7 +2724,7 @@
 
 	if (config->direction == DMA_DEV_TO_MEM) {
 		dma_addr_t dev_addr_rx =
-			d40c->base->plat_data->dev_rx[cfg->src_dev_type];
+			d40c->base->plat_data->dev_rx[cfg->dev_type];
 
 		config_addr = config->src_addr;
 		if (dev_addr_rx)
@@ -2778,7 +2747,7 @@
 
 	} else if (config->direction == DMA_MEM_TO_DEV) {
 		dma_addr_t dev_addr_tx =
-			d40c->base->plat_data->dev_tx[cfg->dst_dev_type];
+			d40c->base->plat_data->dev_tx[cfg->dev_type];
 
 		config_addr = config->dst_addr;
 		if (dev_addr_tx)