Currently the driver depends on the bootloader to enable the clocks.
Add support for clocking. The patch enables the clock at probe and
disables them at remove.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xxxxxxxxxx>
Acked-by: Felipe Balbi <balbi@xxxxxxxxxx>
---
v3:
Add dev_warn
drivers/usb/gadget/udc/udc-xilinx.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)
diff --git a/drivers/usb/gadget/udc/udc-xilinx.c b/drivers/usb/gadget/udc/udc-xilinx.c
index fb4ffedd6f0d..f5ca670776a3 100644
--- a/drivers/usb/gadget/udc/udc-xilinx.c
+++ b/drivers/usb/gadget/udc/udc-xilinx.c
@@ -11,6 +11,7 @@
* USB peripheral controller (at91_udc.c).
*/
+#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
@@ -171,6 +172,7 @@ struct xusb_ep {
* @addr: the usb device base address
* @lock: instance of spinlock
* @dma_enabled: flag indicating whether the dma is included in the system
+ * @clk: pointer to struct clk
* @read_fn: function pointer to read device registers
* @write_fn: function pointer to write to device registers
*/
@@ -188,6 +190,7 @@ struct xusb_udc {
void __iomem *addr;
spinlock_t lock;
bool dma_enabled;
+ struct clk *clk;
unsigned int (*read_fn)(void __iomem *);
void (*write_fn)(void __iomem *, u32, u32);
@@ -2092,6 +2095,27 @@ static int xudc_probe(struct platform_device *pdev)
udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
udc->gadget.name = driver_name;
+ udc->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
+ if (IS_ERR(udc->clk)) {
+ if (PTR_ERR(udc->clk) != -ENOENT) {
+ ret = PTR_ERR(udc->clk);
+ goto fail;
+ }
+
+ /*
+ * Clock framework support is optional, continue on,
+ * anyways if we don't find a matching clock
+ */
+ dev_warn(&pdev->dev, "s_axi_aclk clock property is not found\n");
+ udc->clk = NULL;
+ }
+
+ ret = clk_prepare_enable(udc->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to enable clock.\n");
+ return ret;
+ }
+
spin_lock_init(&udc->lock);
/* Check for IP endianness */
@@ -2147,6 +2171,7 @@ static int xudc_remove(struct platform_device *pdev)
struct xusb_udc *udc = platform_get_drvdata(pdev);
usb_del_gadget_udc(&udc->gadget);
+ clk_disable_unprepare(udc->clk);
return 0;
}
--
2.25.1
