USB: gadget: udc: Process disconnect synchronously

As the comment in usb_disconnect() hints, do not defer the
disconnect processing, and instead just do it directly in
the irq handler. This allows the driver to avoid using a
nowadays deprecated tasklet.

Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Link: https://lore.kernel.org/r/20210119001653.127975-1-dave@stgolabs.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
index 6c726d2..d046c09 100644 (file)
--- a/drivers/usb/gadget/udc/snps_udc_core.c
+++ b/drivers/usb/gadget/udc/snps_udc_core.c
@@ -36,7 +36,6 @@
 #include <asm/unaligned.h>
 #include "amd5536udc.h"
 
-static void udc_tasklet_disconnect(unsigned long);
 static void udc_setup_endpoints(struct udc *dev);
 static void udc_soft_reset(struct udc *dev);
 static struct udc_request *udc_alloc_bna_dummy(struct udc_ep *ep);
@@ -95,9 +94,6 @@ static struct timer_list udc_pollstall_timer;
 static int stop_pollstall_timer;
 static DECLARE_COMPLETION(on_pollstall_exit);
 
-/* tasklet for usb disconnect */
-static DECLARE_TASKLET_OLD(disconnect_tasklet, udc_tasklet_disconnect);
-
 /* endpoint names used for print */
 static const char ep0_string[] = "ep0in";
 static const struct {
@@ -1637,6 +1633,8 @@ static void usb_connect(struct udc *dev)
  */
 static void usb_disconnect(struct udc *dev)
 {
+       u32 tmp;
+
        /* Return if already disconnected */
        if (!dev->connected)
                return;
@@ -1648,23 +1646,6 @@ static void usb_disconnect(struct udc *dev)
        /* mask interrupts */
        udc_mask_unused_interrupts(dev);
 
-       /* REVISIT there doesn't seem to be a point to having this
-        * talk to a tasklet ... do it directly, we already hold
-        * the spinlock needed to process the disconnect.
-        */
-
-       tasklet_schedule(&disconnect_tasklet);
-}
-
-/* Tasklet for disconnect to be outside of interrupt context */
-static void udc_tasklet_disconnect(unsigned long par)
-{
-       struct udc *dev = udc;
-       u32 tmp;
-
-       DBG(dev, "Tasklet disconnect\n");
-       spin_lock_irq(&dev->lock);
-
        if (dev->driver) {
                spin_unlock(&dev->lock);
                dev->driver->disconnect(&dev->gadget);
@@ -1673,13 +1654,10 @@ static void udc_tasklet_disconnect(unsigned long par)
                /* empty queues */
                for (tmp = 0; tmp < UDC_EP_NUM; tmp++)
                        empty_req_queue(&dev->ep[tmp]);
-
        }
 
        /* disable ep0 */
-       ep_init(dev->regs,
-                       &dev->ep[UDC_EP0IN_IX]);
-
+       ep_init(dev->regs, &dev->ep[UDC_EP0IN_IX]);
 
        if (!soft_reset_occured) {
                /* init controller by soft reset */
@@ -1695,8 +1673,6 @@ static void udc_tasklet_disconnect(unsigned long par)
                tmp = AMD_ADDBITS(tmp, UDC_DEVCFG_SPD_FS, UDC_DEVCFG_SPD);
                writel(tmp, &dev->regs->cfg);
        }
-
-       spin_unlock_irq(&dev->lock);
 }
 
 /* Reset the UDC core */