[PATCH] usb: ohci-ppc-of: use platform for irq and ioremap

[PATCH] usb: ohci-ppc-of: use platform for irq and ioremap

[Rosen Penev]

Replace the open-coded of_address_to_resource() plus devm_ioremap_resource()
sequence with devm_platform_get_and_ioremap_resource(), which looks up the
resource and maps it in one call. The helper returns a pointer to the
resource, so update rsrc_start / rsrc_len to dereference it and assign the
mapped address to hcd->regs. Use a separate on-stack resource (ehci_res)
for the unrelated ibm,usb-ehci-440epx erratum lookup rather than aliasing
the returned resource pointer.

Switch IRQ acquisition from irq_of_parse_and_map() to platform_get_irq(),
which only retrieves the interrupt the OF/platform core has already set up
rather than transferring mapping ownership to the driver. Drop the now
unneeded irq_dispose_mapping() calls (probe error path and
ohci_hcd_ppc_of_remove()) and the now-unused of_irq.h include, keeping
linux/of_address.h for the erratum block's of_address_to_resource().

Behaviorally equivalent with respect to region reservation: the prior code
used devm_ioremap_resource(), which already reserved the region.

Built for PowerPC (ppc44x_defconfig + CONFIG_USB_OHCI_HCD_PPC_OF) with
LLVM=1; drivers/usb/host/ohci-hcd.o (which includes ohci-ppc-of.c)
compiles cleanly.

Assisted-by: opencode:hy3-free
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/usb/host/ohci-ppc-of.c | 44 +++++++++++++---------------------
 1 file changed, 16 insertions(+), 28 deletions(-)

diff --git a/drivers/usb/host/ohci-ppc-of.c b/drivers/usb/host/ohci-ppc-of.c
index acd0a0e398a4..3a965b9c04fa 100644
--- a/drivers/usb/host/ohci-ppc-of.c
+++ b/drivers/usb/host/ohci-ppc-of.c
@@ -17,7 +17,6 @@
 #include <linux/signal.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
-#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 
 static int
@@ -87,7 +86,9 @@ static int ohci_hcd_ppc_of_probe(struct platform_device *op)
 	struct device_node *dn = op->dev.of_node;
 	struct usb_hcd *hcd;
 	struct ohci_hcd	*ohci;
-	struct resource res;
+	struct resource *res;
+	struct resource ehci_res;
+	void __iomem *regs;
 	int irq;
 
 	int rv;
@@ -103,30 +104,21 @@ static int ohci_hcd_ppc_of_probe(struct platform_device *op)
 
 	dev_dbg(&op->dev, "initializing PPC-OF USB Controller\n");
 
-	rv = of_address_to_resource(dn, 0, &res);
-	if (rv)
-		return rv;
+	regs = devm_platform_get_and_ioremap_resource(op, 0, &res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	irq = platform_get_irq(op, 0);
+	if (irq < 0)
+		return irq;
 
 	hcd = usb_create_hcd(&ohci_ppc_of_hc_driver, &op->dev, "PPC-OF USB");
 	if (!hcd)
 		return -ENOMEM;
 
-	hcd->rsrc_start = res.start;
-	hcd->rsrc_len = resource_size(&res);
-
-	hcd->regs = devm_ioremap_resource(&op->dev, &res);
-	if (IS_ERR(hcd->regs)) {
-		rv = PTR_ERR(hcd->regs);
-		goto err_rmr;
-	}
-
-	irq = irq_of_parse_and_map(dn, 0);
-	if (!irq) {
-		dev_err(&op->dev, "%s: irq_of_parse_and_map failed\n",
-			__FILE__);
-		rv = -EBUSY;
-		goto err_rmr;
-	}
+	hcd->rsrc_start = res->start;
+	hcd->rsrc_len = resource_size(res);
+	hcd->regs = regs;
 
 	ohci = hcd_to_ohci(hcd);
 	if (is_bigendian) {
@@ -158,20 +150,18 @@ static int ohci_hcd_ppc_of_probe(struct platform_device *op)
 	* the ehci driver is loaded.
 	*/
 	if (np !=  NULL) {
-		if (!of_address_to_resource(np, 0, &res)) {
-			if (!request_mem_region(res.start, 0x4, hcd_name)) {
+		if (!of_address_to_resource(np, 0, &ehci_res)) {
+			if (!request_mem_region(ehci_res.start, 0x4, hcd_name)) {
 				writel_be((readl_be(&ohci->regs->control) |
 					OHCI_USB_SUSPEND), &ohci->regs->control);
 					(void) readl_be(&ohci->regs->control);
 			} else
-				release_mem_region(res.start, 0x4);
+				release_mem_region(ehci_res.start, 0x4);
 		} else
 			pr_debug("%s: cannot get ehci offset from fdt\n", __FILE__);
 		of_node_put(np);
 	}
 
-	irq_dispose_mapping(irq);
-err_rmr:
  	usb_put_hcd(hcd);
 
 	return rv;
@@ -185,8 +175,6 @@ static void ohci_hcd_ppc_of_remove(struct platform_device *op)
 
 	usb_remove_hcd(hcd);
 
-	irq_dispose_mapping(hcd->irq);
-
 	usb_put_hcd(hcd);
 }
 
-- 
2.55.0