diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2022-02-23 18:12:40 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-25 12:36:31 +0300 |
| commit | 5318f70da7e82649d794fc27d8a127c22aa3566e (patch) | |
| tree | 2e787bf868ea7d7d36d5300a5c66a9cb0c6369cb /drivers/tty/serial | |
| parent | 67ec6dd0b257bd81b4e9fcac89b29da72f6265e5 (diff) | |
| download | linux-5318f70da7e82649d794fc27d8a127c22aa3566e.tar.xz | |
serial: 8250_lpss: Balance reference count for PCI DMA device
The pci_get_slot() increases its reference count, the caller
must decrement the reference count by calling pci_dev_put().
Fixes: 9a1870ce812e ("serial: 8250: don't use slave_id of dma_slave_config")
Depends-on: a13e19cf3dc1 ("serial: 8250_lpss: split LPSS driver to separate module")
Reported-by: Qing Wang <wangqing@vivo.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220223151240.70248-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
| -rw-r--r-- | drivers/tty/serial/8250/8250_lpss.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c index d3bafec7619d..0f5af061e0b4 100644 --- a/drivers/tty/serial/8250/8250_lpss.c +++ b/drivers/tty/serial/8250/8250_lpss.c @@ -117,8 +117,7 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { struct dw_dma_slave *param = &lpss->dma_param; struct pci_dev *pdev = to_pci_dev(port->dev); - unsigned int dma_devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0); - struct pci_dev *dma_dev = pci_get_slot(pdev->bus, dma_devfn); + struct pci_dev *dma_dev; switch (pdev->device) { case PCI_DEVICE_ID_INTEL_BYT_UART1: @@ -137,6 +136,8 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) return -EINVAL; } + dma_dev = pci_get_slot(pdev->bus, PCI_DEVFN(PCI_SLOT(pdev->devfn), 0)); + param->dma_dev = &dma_dev->dev; param->m_master = 0; param->p_master = 1; @@ -152,6 +153,14 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) return 0; } +static void byt_serial_exit(struct lpss8250 *lpss) +{ + struct dw_dma_slave *param = &lpss->dma_param; + + /* Paired with pci_get_slot() in the byt_serial_setup() above */ + put_device(param->dma_dev); +} + static int ehl_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { struct uart_8250_dma *dma = &lpss->data.dma; @@ -170,6 +179,13 @@ static int ehl_serial_setup(struct lpss8250 *lpss, struct uart_port *port) return 0; } +static void ehl_serial_exit(struct lpss8250 *lpss) +{ + struct uart_8250_port *up = serial8250_get_port(lpss->data.line); + + up->dma = NULL; +} + #ifdef CONFIG_SERIAL_8250_DMA static const struct dw_dma_platform_data qrk_serial_dma_pdata = { .nr_channels = 2, @@ -344,8 +360,7 @@ static int lpss8250_probe(struct pci_dev *pdev, const struct pci_device_id *id) return 0; err_exit: - if (lpss->board->exit) - lpss->board->exit(lpss); + lpss->board->exit(lpss); pci_free_irq_vectors(pdev); return ret; } @@ -356,8 +371,7 @@ static void lpss8250_remove(struct pci_dev *pdev) serial8250_unregister_port(lpss->data.line); - if (lpss->board->exit) - lpss->board->exit(lpss); + lpss->board->exit(lpss); pci_free_irq_vectors(pdev); } @@ -365,12 +379,14 @@ static const struct lpss8250_board byt_board = { .freq = 100000000, .base_baud = 2764800, .setup = byt_serial_setup, + .exit = byt_serial_exit, }; static const struct lpss8250_board ehl_board = { .freq = 200000000, .base_baud = 12500000, .setup = ehl_serial_setup, + .exit = ehl_serial_exit, }; static const struct lpss8250_board qrk_board = { |