From: Sherry Sun sherry.sun@nxp.com
[ Upstream commit f398e0aa325c61fa20903833a5b534ecb8e6e418 ]
Now fsl_lpuart driver use both of_alias_get_id() and ida_simple_get() in .probe(), which has the potential bug. For example, when remove the lpuart7 alias in dts, of_alias_get_id() will return error, then call ida_simple_get() to allocate the id 0 for lpuart7, this may confilct with the lpuart4 which has alias 0.
aliases { ... serial0 = &lpuart4; serial1 = &lpuart5; serial2 = &lpuart6; serial3 = &lpuart7; }
So remove the ida_simple_get() in .probe(), return an error directly when calling of_alias_get_id() fails, which is consistent with other uart drivers behavior.
Fixes: 3bc3206e1c0f ("serial: fsl_lpuart: Remove the alias node dependence") Signed-off-by: Sherry Sun sherry.sun@nxp.com Link: https://lore.kernel.org/r/20220321112211.8895-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/fsl_lpuart.c | 24 ++++-------------------- 1 file changed, 4 insertions(+), 20 deletions(-)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index b9f8add284e3..52a603a6f9b8 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -229,8 +229,6 @@ /* IMX lpuart has four extra unused regs located at the beginning */ #define IMX_REG_OFF 0x10
-static DEFINE_IDA(fsl_lpuart_ida); - enum lpuart_type { VF610_LPUART, LS1021A_LPUART, @@ -265,7 +263,6 @@ struct lpuart_port { int rx_dma_rng_buf_len; unsigned int dma_tx_nents; wait_queue_head_t dma_wait; - bool id_allocated; };
struct lpuart_soc_data { @@ -2638,23 +2635,18 @@ static int lpuart_probe(struct platform_device *pdev)
ret = of_alias_get_id(np, "serial"); if (ret < 0) { - ret = ida_simple_get(&fsl_lpuart_ida, 0, UART_NR, GFP_KERNEL); - if (ret < 0) { - dev_err(&pdev->dev, "port line is full, add device failed\n"); - return ret; - } - sport->id_allocated = true; + dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret); + return ret; } if (ret >= ARRAY_SIZE(lpuart_ports)) { dev_err(&pdev->dev, "serial%d out of range\n", ret); - ret = -EINVAL; - goto failed_out_of_range; + return -EINVAL; } sport->port.line = ret;
ret = lpuart_enable_clks(sport); if (ret) - goto failed_clock_enable; + return ret; sport->port.uartclk = lpuart_get_baud_clk_rate(sport);
lpuart_ports[sport->port.line] = sport; @@ -2697,10 +2689,6 @@ static int lpuart_probe(struct platform_device *pdev) failed_attach_port: failed_irq_request: lpuart_disable_clks(sport); -failed_clock_enable: -failed_out_of_range: - if (sport->id_allocated) - ida_simple_remove(&fsl_lpuart_ida, sport->port.line); return ret; }
@@ -2710,9 +2698,6 @@ static int lpuart_remove(struct platform_device *pdev)
uart_remove_one_port(&lpuart_reg, &sport->port);
- if (sport->id_allocated) - ida_simple_remove(&fsl_lpuart_ida, sport->port.line); - lpuart_disable_clks(sport);
if (sport->dma_tx_chan) @@ -2842,7 +2827,6 @@ static int __init lpuart_serial_init(void)
static void __exit lpuart_serial_exit(void) { - ida_destroy(&fsl_lpuart_ida); platform_driver_unregister(&lpuart_driver); uart_unregister_driver(&lpuart_reg); }