usb: gadget: lpc32xx_udc: fix clock imbalance in error path

A recent change fixing a device reference leak introduced a clock
imbalance by reusing an error path so that the clock may be disabled
before having been enabled.

Note that the clock framework allows for passing in NULL clocks so there
is no risk for a NULL pointer dereference.

Also drop the bogus I2C client NULL check added by the offending commit
as the pointer has already been verified to be non-NULL.

Fixes: c841179 ("USB: lpc32xx_udc: Fix error handling in probe")
Cc: [email protected]
Cc: Ma Ke <[email protected]>
Signed-off-by: Johan Hovold <[email protected]>
Reviewed-by: Vladimir Zapolskiy <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: jhovold

drivers/usb/gadget/udc/lpc32xx_udc.c

@@ -3020,7 +3020,7 @@ static int lpc32xx_udc_probe(struct platform_device *pdev)
 	pdev->dev.dma_mask = &lpc32xx_usbd_dmamask;
 	retval = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(32));
 	if (retval)
-		goto i2c_fail;
+		goto err_put_client;
 
 	udc->board = &lpc32xx_usbddata;
 
@@ -3040,30 +3040,30 @@ static int lpc32xx_udc_probe(struct platform_device *pdev)
 		udc->udp_irq[i] = platform_get_irq(pdev, i);
 		if (udc->udp_irq[i] < 0) {
 			retval = udc->udp_irq[i];
-			goto i2c_fail;
+			goto err_put_client;
 		}
 	}
 
 	udc->udp_baseaddr = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(udc->udp_baseaddr)) {
 		dev_err(udc->dev, "IO map failure\n");
 		retval = PTR_ERR(udc->udp_baseaddr);
-		goto i2c_fail;
+		goto err_put_client;
 	}
 
 	/* Get USB device clock */
 	udc->usb_slv_clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(udc->usb_slv_clk)) {
 		dev_err(udc->dev, "failed to acquire USB device clock\n");
 		retval = PTR_ERR(udc->usb_slv_clk);
-		goto i2c_fail;
+		goto err_put_client;
 	}
 
 	/* Enable USB device clock */
 	retval = clk_prepare_enable(udc->usb_slv_clk);
 	if (retval < 0) {
 		dev_err(udc->dev, "failed to start USB device clock\n");
-		goto i2c_fail;
+		goto err_put_client;
 	}
 
 	/* Setup deferred workqueue data */
@@ -3165,9 +3165,10 @@ static int lpc32xx_udc_probe(struct platform_device *pdev)
 	dma_free_coherent(&pdev->dev, UDCA_BUFF_SIZE,
 			  udc->udca_v_base, udc->udca_p_base);
 i2c_fail:
-	if (udc->isp1301_i2c_client)
-		put_device(&udc->isp1301_i2c_client->dev);
 	clk_disable_unprepare(udc->usb_slv_clk);
+err_put_client:
+	put_device(&udc->isp1301_i2c_client->dev);
+
 	dev_err(udc->dev, "%s probe failed, %d\n", driver_name, retval);
 
 	return retval;
@@ -3195,10 +3196,9 @@ static void lpc32xx_udc_remove(struct platform_device *pdev)
 	dma_free_coherent(&pdev->dev, UDCA_BUFF_SIZE,
 			  udc->udca_v_base, udc->udca_p_base);
 
-	if (udc->isp1301_i2c_client)
-		put_device(&udc->isp1301_i2c_client->dev);
-
 	clk_disable_unprepare(udc->usb_slv_clk);
+
+	put_device(&udc->isp1301_i2c_client->dev);
 }
 
 #ifdef CONFIG_PM