drivers: usb: nordic: Power consumption fix with cable detached

This commit fixes the issue with excess current being drawn
during sleep due to active HFCLK with external crystal.
Clock-related operations were moved to cable attachmend and
detachment handlers to ensure that HFCLK is not requested
when it's not needed.

Signed-off-by: Paweł Zadrożniak <[email protected]>

Author: pawelzadrozniak

drivers/usb/device/usb_dc_nrfx.c

@@ -525,6 +525,7 @@ static int hf_clock_enable(bool on, bool blocking)
 {
 	int ret = -ENODEV;
 	struct device *clock;
+	static bool clock_requested;
 
 	clock = device_get_binding(CONFIG_CLOCK_CONTROL_NRF_M16SRC_DRV_NAME);
 	if (!clock) {
@@ -533,8 +534,18 @@ static int hf_clock_enable(bool on, bool blocking)
 	}
 
 	if (on) {
+		if (clock_requested) {
+			/* Do not request HFCLK multiple times. */
+			return 0;
+		}
 		ret = clock_control_on(clock, (void *)blocking);
 	} else {
+		if (!clock_requested) {
+			/* Cancel the operation if clock has not
+			 * been requested by this driver before.
+			 */
+			return 0;
+		}
 		ret = clock_control_off(clock, (void *)blocking);
 	}
 
@@ -544,9 +555,14 @@ static int hf_clock_enable(bool on, bool blocking)
 		return ret;
 	}
 
+	clock_requested = on;
 	LOG_DBG("HF clock %s success (%d)", on ? "start" : "stop", ret);
 
-	return ret;
+	/* NOTE: Non-blocking HF clock enable can return -EINPROGRESS
+	 * if HF clock start was already requested. Such error code
+	 * does not need to be propagated, hence returned value is 0.
+	 */
+	return 0;
 }
 
 static void usbd_enable_endpoints(struct nrf_usbd_ctx *ctx)
@@ -731,6 +747,8 @@ static inline void usbd_work_process_pwr_events(struct usbd_pwr_event *pwr_evt)
 	case USBD_ATTACHED:
 		LOG_DBG("USB detected");
 		nrfx_usbd_enable();
+		(void) hf_clock_enable(true, false);
+
 		break;
 
 	case USBD_POWERED:
@@ -748,6 +766,7 @@ static inline void usbd_work_process_pwr_events(struct usbd_pwr_event *pwr_evt)
 		LOG_DBG("USB Removed");
 		ctx->ready = false;
 		nrfx_usbd_disable();
+		(void) hf_clock_enable(false, false);
 
 		if (ctx->status_cb) {
 			ctx->status_cb(USB_DC_DISCONNECTED, NULL);
@@ -1248,14 +1267,6 @@ int usb_dc_attach(void)
 		    DT_NORDIC_NRF_USBD_USBD_0_IRQ_PRIORITY,
 		    nrfx_isr, nrfx_usbd_irq_handler, 0);
 
-	/* NOTE: Non-blocking HF clock enable can return -EINPROGRESS
-	 * if HF clock start was already requested.
-	 */
-	ret = hf_clock_enable(true, false);
-	if (ret && ret != -EINPROGRESS) {
-		return ret;
-	}
-
 	err = nrfx_usbd_init(usbd_event_handler);
 
 	if (err != NRFX_SUCCESS) {
@@ -1280,7 +1291,6 @@ int usb_dc_attach(void)
 int usb_dc_detach(void)
 {
 	struct nrf_usbd_ctx *ctx = get_usbd_ctx();
-	int ret;
 
 	k_mutex_lock(&ctx->drv_lock, K_FOREVER);
 
@@ -1289,18 +1299,13 @@ int usb_dc_detach(void)
 
 	nrfx_usbd_disable();
 	nrfx_usbd_uninit();
-
-	ret = hf_clock_enable(false, false);
-	if (ret) {
-		return ret;
-		k_mutex_unlock(&ctx->drv_lock);
-	}
-
+	(void) hf_clock_enable(false, false);
 	nrf5_power_usb_power_int_enable(false);
 
 	ctx->attached = false;
 	k_mutex_unlock(&ctx->drv_lock);
-	return ret;
+
+	return 0;
 }
 
 int usb_dc_reset(void)