pci_ioremap_bar could fail. The patch returns in case of failure to acquire IOMEM. It also releases the acquired resource in the exit path. Signed-off-by: Aditya Pakki <pakki001@xxxxxxx> --- v3: Change the order of pci_iounmap and dw_dma_remove v2: Failed to release resource in exit path and incorrect code in non DMA case, suggested by Andy Shevchenko v1: Missed return by default in CONFIG_SERIAL_8250_DMA, suggested by Jiri Slaby --- drivers/tty/serial/8250/8250_lpss.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c index 53ca9ba6ab4b..69d6e32da713 100644 --- a/drivers/tty/serial/8250/8250_lpss.c +++ b/drivers/tty/serial/8250/8250_lpss.c @@ -170,9 +170,11 @@ static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port) int ret; chip->dev = &pdev->dev; + chip->pdata = &qrk_serial_dma_pdata; chip->irq = pci_irq_vector(pdev, 0); chip->regs = pci_ioremap_bar(pdev, 1); - chip->pdata = &qrk_serial_dma_pdata; + if (!chip->regs) + return; /* Falling back to PIO mode if DMA probing fails */ ret = dw_dma_probe(chip); @@ -199,7 +201,10 @@ static void qrk_serial_exit_dma(struct lpss8250 *lpss) if (!param->dma_dev) return; + dw_dma_remove(&lpss->dma_chip); + + pci_iounmap(param->dma_dev, &lpss->dma_chip->regs); } #else /* CONFIG_SERIAL_8250_DMA */ static void qrk_serial_setup_dma(struct lpss8250 *lpss, struct uart_port *port) {} -- 2.17.1