USB: pxa27x_udc: check return value of clk_enable

clk_enable() may fail according to the API contract.
Previously, udc_enable() ignored its return value and returned void.

Modify udc_enable() to return the error code. Additionally, update
all of its callers (pxa_udc_pullup, pxa_udc_vbus_session,
pxa27x_udc_start, pxa_udc_probe, and pxa_udc_resume) to check
this return value and handle the failure properly with necessary
cleanups or rollbacks.

Signed-off-by: Zhaoyang Yu <2426767509@qq.com>
Link: https://patch.msgid.link/tencent_46693FE6DB434ACFB7412B16F6078AC01A06@qq.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/pxa27x_udc.c b/drivers/usb/gadget/udc/pxa27x_udc.c
index 4fac477d24c05ef4bb460c74461fd98cecc0aeae..1abea0d48c35d29f94d123fbca3b77929bac159a 100644 (file)
--- a/drivers/usb/gadget/udc/pxa27x_udc.c
+++ b/drivers/usb/gadget/udc/pxa27x_udc.c
@@ -1462,7 +1462,7 @@ static int pxa_udc_wakeup(struct usb_gadget *_gadget)
        return 0;
 }
 
-static void udc_enable(struct pxa_udc *udc);
+static int udc_enable(struct pxa_udc *udc);
 static void udc_disable(struct pxa_udc *udc);
 
 /**
@@ -1519,14 +1519,20 @@ static int should_disable_udc(struct pxa_udc *udc)
 static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active)
 {
        struct pxa_udc *udc = to_gadget_udc(_gadget);
+       int ret;
 
        if (!udc->gpiod && !udc->udc_command)
                return -EOPNOTSUPP;
 
        dplus_pullup(udc, is_active);
 
-       if (should_enable_udc(udc))
-               udc_enable(udc);
+       if (should_enable_udc(udc)) {
+               ret = udc_enable(udc);
+               if (ret) {
+                       dplus_pullup(udc, !is_active);
+                       return ret;
+               }
+       }
        if (should_disable_udc(udc))
                udc_disable(udc);
        return 0;
@@ -1545,10 +1551,16 @@ static int pxa_udc_pullup(struct usb_gadget *_gadget, int is_active)
 static int pxa_udc_vbus_session(struct usb_gadget *_gadget, int is_active)
 {
        struct pxa_udc *udc = to_gadget_udc(_gadget);
+       int ret;
 
        udc->vbus_sensed = is_active;
-       if (should_enable_udc(udc))
-               udc_enable(udc);
+       if (should_enable_udc(udc)) {
+               ret = udc_enable(udc);
+               if (ret) {
+                       udc->vbus_sensed = !is_active;
+                       return ret;
+               }
+       }
        if (should_disable_udc(udc))
                udc_disable(udc);
 
@@ -1691,12 +1703,18 @@ static void udc_init_data(struct pxa_udc *dev)
  * Enables the udc device : enables clocks, udc interrupts, control endpoint
  * interrupts, sets usb as UDC client and setups endpoints.
  */
-static void udc_enable(struct pxa_udc *udc)
+static int udc_enable(struct pxa_udc *udc)
 {
+       int ret;
+
        if (udc->enabled)
-               return;
+               return 0;
 
-       clk_enable(udc->clk);
+       ret = clk_enable(udc->clk);
+       if (ret) {
+               dev_err(udc->dev, "clk_enable failed: %d\n", ret);
+               return ret;
+       }
        udc_writel(udc, UDCICR0, 0);
        udc_writel(udc, UDCICR1, 0);
        udc_clear_mask_UDCCR(udc, UDCCR_UDE);
@@ -1726,6 +1744,8 @@ static void udc_enable(struct pxa_udc *udc)
        pio_irq_enable(&udc->pxa_ep[0]);
 
        udc->enabled = 1;
+
+       return 0;
 }
 
 /**
@@ -1761,10 +1781,16 @@ static int pxa27x_udc_start(struct usb_gadget *g,
                }
        }
 
-       if (should_enable_udc(udc))
-               udc_enable(udc);
+       if (should_enable_udc(udc)) {
+               retval = udc_enable(udc);
+               if (retval)
+                       goto fail_enable;
+       }
        return 0;
 
+fail_enable:
+       if (!IS_ERR_OR_NULL(udc->transceiver))
+               otg_set_peripheral(udc->transceiver->otg, NULL);
 fail:
        udc->driver = NULL;
        return retval;
@@ -2430,10 +2456,16 @@ static int pxa_udc_probe(struct platform_device *pdev)
                goto err_add_gadget;
 
        pxa_init_debugfs(udc);
-       if (should_enable_udc(udc))
-               udc_enable(udc);
+       if (should_enable_udc(udc)) {
+               retval = udc_enable(udc);
+               if (retval)
+                       goto err_enable;
+       }
        return 0;
 
+err_enable:
+       usb_del_gadget_udc(&udc->gadget);
+       pxa_cleanup_debugfs(udc);
 err_add_gadget:
        if (!IS_ERR_OR_NULL(udc->transceiver))
                usb_unregister_notifier(udc->transceiver, &pxa27x_udc_phy);
@@ -2509,13 +2541,19 @@ static int pxa_udc_resume(struct platform_device *_dev)
 {
        struct pxa_udc *udc = platform_get_drvdata(_dev);
        struct pxa_ep *ep;
+       int ret;
 
        ep = &udc->pxa_ep[0];
        udc_ep_writel(ep, UDCCSR, udc->udccsr0 & (UDCCSR0_FST | UDCCSR0_DME));
 
        dplus_pullup(udc, udc->pullup_resume);
-       if (should_enable_udc(udc))
-               udc_enable(udc);
+       if (should_enable_udc(udc)) {
+               ret = udc_enable(udc);
+               if (ret) {
+                       dplus_pullup(udc, !udc->pullup_resume);
+                       return ret;
+               }
+       }
        /*
         * We do not handle OTG yet.
         *