clk: zynq: fix up address from DT

The upstream Zynq 7000 DT describes the SLCR child devices physical
address as an offset within the SLCR. The driver thus needs to add
the SLCR base offset to the address before trying to map the MMIO
region.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 23 insertions, 1 deletions

diff --git a/drivers/clk/zynq/clkc.c b/drivers/clk/zynq/clkc.c
index 07152e2ada..90ab71fe96 100644
--- a/drivers/clk/zynq/clkc.c
+++ b/drivers/clk/zynq/clkc.c
@@ -373,10 +373,32 @@ static int zynq_clock_probe(struct device_d *dev)
 	struct resource *iores;
 	void __iomem *clk_base;
 	unsigned long ps_clk_rate = 33333330;
+	resource_size_t slcr_offset = 0;
 
-	iores = dev_request_mem_resource(dev, 0);
+	iores = dev_get_resource(dev, IORESOURCE_MEM, 0);
 	if (IS_ERR(iores))
 		return PTR_ERR(iores);
+
+	/*
+	 * The Zynq 7000 DT describes the SLCR child devices with a reg offset
+	 * in the SCLR region. So we can't directly map the address we get from
+	 * the DT, but need to add the SCLR base offset.
+	 */
+	if (dev->device_node) {
+		struct resource *parent_res;
+
+		parent_res = dev_get_resource(dev->parent, IORESOURCE_MEM, 0);
+		if (IS_ERR(parent_res))
+			return PTR_ERR(parent_res);
+
+		slcr_offset = parent_res->start;
+	}
+
+	iores = request_iomem_region(dev_name(dev), iores->start + slcr_offset,
+				     iores->end + slcr_offset);
+	if (IS_ERR(iores))
+		return PTR_ERR(iores);
+
 	clk_base = IOMEM(iores->start);
 
 	clks[ps_clk]  = clk_fixed("ps_clk", ps_clk_rate);