[PATCH] USB: gadget: udc: Process disconnect synchronously

From: Davidlohr Bueso
Date: Mon Jan 18 2021 - 19:18:15 EST


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.

Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
---
drivers/usb/gadget/udc/snps_udc_core.c | 30 +++-----------------------
1 file changed, 3 insertions(+), 27 deletions(-)

diff --git a/drivers/usb/gadget/udc/snps_udc_core.c b/drivers/usb/gadget/udc/snps_udc_core.c
index 6c726d2e1788..d046c09fa566 100644
--- 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 */
--
2.26.2