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: c84117912bdd ("USB: lpc32xx_udc: Fix error handling in probe")
Cc: stable@vger.kernel.org
Cc: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Vladimir Zapolskiy <vz@mleia.com>
Link: https://patch.msgid.link/20251218153519.19453-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index 73c0f28a85852f4ec5716f7b47e42c3e9af28856..a962d4294fbec68cb3c164882d5463746c328b11 100644 (file)
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/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;
 
@@ -3040,7 +3040,7 @@ 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;
                }
        }
 
@@ -3048,7 +3048,7 @@ static int lpc32xx_udc_probe(struct platform_device *pdev)
        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 */
@@ -3056,14 +3056,14 @@ static int lpc32xx_udc_probe(struct platform_device *pdev)
        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 @@ dma_alloc_fail:
        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