dmaengine: ste_dma40: Calculate number of logical channels from physical ones

This change will cost ~25KB of memory, but it's worth the trade-off,
as it removes a great deal of overhead. It means that instead of only
allocating memory for the logical channels in use, it does so for all
available ones, which is 32 per physical channel. However, this now
means we can remove some platform data and we don't have to worry
about adding vendor specific variables to Device Tree.

Acked-by: Vinod Koul <vnod.koul@intel.com>
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 367ef15..f25c9cc 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -45,6 +45,9 @@
 #define D40_LCLA_LINK_PER_EVENT_GRP 128
 #define D40_LCLA_END D40_LCLA_LINK_PER_EVENT_GRP
 
+/* Max number of logical channels per physical channel */
+#define D40_MAX_LOG_CHAN_PER_PHY 32
+
 /* Attempts before giving up to trying to get pages that are aligned */
 #define MAX_LCLA_ALLOC_ATTEMPTS 256
 
@@ -3210,6 +3213,8 @@
 	else
 		num_phy_chans = 4 * (readl(virtbase + D40_DREG_ICFG) & 0x7) + 4;
 
+	num_log_chans = num_phy_chans * D40_MAX_LOG_CHAN_PER_PHY;
+
 	dev_info(&pdev->dev, "hardware revision: %d @ 0x%x with %d physical channels\n",
 		 rev, res->start, num_phy_chans);
 
@@ -3219,15 +3224,6 @@
 		goto failure;
 	}
 
-	/* Count the number of logical channels in use */
-	for (i = 0; i < plat_data->dev_len; i++)
-		if (plat_data->dev_rx[i] != 0)
-			num_log_chans++;
-
-	for (i = 0; i < plat_data->dev_len; i++)
-		if (plat_data->dev_tx[i] != 0)
-			num_log_chans++;
-
 	base = kzalloc(ALIGN(sizeof(struct d40_base), 4) +
 		       (num_phy_chans + num_log_chans + ARRAY_SIZE(dma40_memcpy_channels)) *
 		       sizeof(struct d40_chan), GFP_KERNEL);
@@ -3295,7 +3291,7 @@
 		 * The max number of logical channels are event lines for all
 		 * src devices and dst devices
 		 */
-		base->lookup_log_chans = kzalloc(plat_data->dev_len * 2 *
+		base->lookup_log_chans = kzalloc(num_log_chans *
 						 sizeof(struct d40_chan *),
 						 GFP_KERNEL);
 		if (!base->lookup_log_chans)