diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 9b803c0aec25..0d9ffa3e2663 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -602,7 +602,6 @@ struct d40_base {
 	struct dma_device		  dma_both;
 	struct dma_device		  dma_slave;
 	struct dma_device		  dma_memcpy;
-	struct d40_chan			 *phy_chans;
 	struct d40_chan			 *log_chans;
 	struct d40_chan			**lookup_log_chans;
 	struct d40_chan			**lookup_phy_chans;
@@ -621,6 +620,7 @@ struct d40_base {
 	u32				 *regs_interrupt;
 	u16				  gcc_pwr_off_mask;
 	struct d40_gen_dmac		  gen_dmac;
+	struct d40_chan			 phy_chans[];
 };
 
 static struct device *chan2dev(struct d40_chan *d40c)
@@ -3128,6 +3128,7 @@ static int __init d40_hw_detect_init(struct platform_device *pdev,
 	struct clk *clk;
 	void __iomem *virtbase;
 	struct d40_base *base;
+	size_t alloc_size;
 	int num_log_chans;
 	int num_phy_chans;
 	int num_memcpy_chans;
@@ -3185,22 +3186,24 @@ static int __init d40_hw_detect_init(struct platform_device *pdev,
 	else
 		num_phy_chans = 4 * (readl(virtbase + D40_DREG_ICFG) & 0x7) + 4;
 
+	num_phy_chans = min(num_phy_chans, STEDMA40_MAX_PHYS);
+
 	/* The number of channels used for memcpy */
 	if (plat_data->num_of_memcpy_chans)
 		num_memcpy_chans = plat_data->num_of_memcpy_chans;
 	else
 		num_memcpy_chans = ARRAY_SIZE(dma40_memcpy_channels);
 
+	num_memcpy_chans = min(num_memcpy_chans, D40_MEMCPY_MAX_CHANS);
 	num_log_chans = num_phy_chans * D40_MAX_LOG_CHAN_PER_PHY;
 
 	dev_info(dev,
 		 "hardware rev: %d with %d physical and %d logical channels\n",
 		 rev, num_phy_chans, num_log_chans);
 
-	base = devm_kzalloc(dev,
-		ALIGN(sizeof(struct d40_base), 4) +
-		(num_phy_chans + num_log_chans + num_memcpy_chans) *
-		sizeof(struct d40_chan), GFP_KERNEL);
+	alloc_size = struct_size(base, phy_chans, num_phy_chans);
+	alloc_size += sizeof(*base->log_chans) * (num_log_chans + num_memcpy_chans);
+	base = devm_kzalloc(dev, alloc_size, GFP_KERNEL);
 
 	if (!base)
 		return -ENOMEM;
@@ -3213,7 +3216,6 @@ static int __init d40_hw_detect_init(struct platform_device *pdev,
 	base->virtbase = virtbase;
 	base->plat_data = plat_data;
 	base->dev = dev;
-	base->phy_chans = ((void *)base) + ALIGN(sizeof(struct d40_base), 4);
 	base->log_chans = &base->phy_chans[num_phy_chans];
 
 	if (base->plat_data->num_of_phy_chans == 14) {