The Aspeed SoCs use uhci-platform. With the new dynamic clock
control framework, the corresponding IP block clock must be
properly enabled.
This is a simplified variant of what ehci-platform does, it
looks for *one* clock attached to the device, and if it's
there, enables it.
Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
---
v3. Fix tab vs. spaces and probe error path
v2. Don't forget to git add latest changes :-) This adds the
part where we turn the clock off when removing the driver.
drivers/usb/host/uhci-hcd.h | 3 +++
drivers/usb/host/uhci-platform.c | 24 ++++++++++++++++++++++--
2 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/host/uhci-hcd.h b/drivers/usb/host/uhci-hcd.h
index f1cc47292a59..7f9f33c8c232 100644
--- a/drivers/usb/host/uhci-hcd.h
+++ b/drivers/usb/host/uhci-hcd.h
@@ -4,6 +4,7 @@
#include <linux/list.h>
#include <linux/usb.h>
+#include <linux/clk.h>
#define usb_packetid(pipe) (usb_pipein(pipe) ? USB_PID_IN : USB_PID_OUT)
#define PIPE_DEVEP_MASK 0x0007ff00
@@ -447,6 +448,8 @@ struct uhci_hcd {
int total_load; /* Sum of array values */
short load[MAX_PHASE]; /* Periodic allocations */
+ struct clk *clk; /* (optional) clock source */
+
/* Reset host controller */
void (*reset_hc) (struct uhci_hcd *uhci);
int (*check_and_reset_hc) (struct uhci_hcd *uhci);
diff --git a/drivers/usb/host/uhci-platform.c b/drivers/usb/host/uhci-platform.c
index 6cb16d4b2257..0d86ad244922 100644
--- a/drivers/usb/host/uhci-platform.c
+++ b/drivers/usb/host/uhci-platform.c
@@ -89,6 +89,8 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
if (!hcd)
return -ENOMEM;
+ uhci = hcd_to_uhci(hcd);
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
hcd->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(hcd->regs)) {
@@ -98,8 +100,6 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
- uhci = hcd_to_uhci(hcd);
-
uhci->regs = hcd->regs;
/* Grab some things from the device-tree */
@@ -119,6 +119,21 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
"Enabled Aspeed implementation workarounds\n");
}
}
+
+ /* Get and enable clock if any specified */
+ uhci->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(uhci->clk)) {
+ ret = PTR_ERR(uhci->clk);
+ goto err_rmr;
+ }
+ if (uhci->clk) {
+ ret = clk_prepare_enable(uhci->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
+ goto err_rmr;
+ }
+ }
+
ret = usb_add_hcd(hcd, pdev->resource[1].start, IRQF_SHARED);
if (ret)
goto err_rmr;
@@ -127,6 +142,8 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
return 0;
err_rmr:
+ if (uhci->clk)
+ clk_disable_unprepare(uhci->clk);
usb_put_hcd(hcd);
return ret;
@@ -135,7 +152,10 @@ static int uhci_hcd_platform_probe(struct platform_device *pdev)
static int uhci_hcd_platform_remove(struct platform_device *pdev)
{
struct usb_hcd *hcd = platform_get_drvdata(pdev);
+ struct uhci_hcd *uhci = hcd_to_uhci(hcd);
+ if (uhci->clk)
+ clk_disable_unprepare(uhci->clk);
usb_remove_hcd(hcd);
usb_put_hcd(hcd);
--
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