From a27d938251ef40c43db81af16fc26b2cec181d4d Mon Sep 17 00:00:00 2001 From: John Garry Date: Thu, 30 Aug 2018 17:08:50 +0800 Subject: [PATCH] serial: 8250_of: Fix for lack of interrupt support In commit c58caaab3bf8 ("serial: 8250: of: Defer probe on missing IRQ"), a check was added for the UART driver being probed prior to the parent IRQ controller. Unfortunately this breaks certain boards which have no interrupt support, like Huawei D03. Indeed, the 8250 DT bindings state that interrupts should be supported - not must. To fix, switch from irq_of_parse_and_map() to of_irq_get(), which does relay whether the IRQ host controller domain is not ready, i.e. defer probe, instead of assuming it. Fixes: c58caaab3bf8 ("serial: 8250: of: Defer probe on missing IRQ") Signed-off-by: John Garry Reviewed-by: Rob Herring Reviewed-by: Alexander Sverdlin Tested-by: Alexander Sverdlin Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_of.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c index af8beefe9b5c..877fd7f8a8ed 100644 --- a/drivers/tty/serial/8250/8250_of.c +++ b/drivers/tty/serial/8250/8250_of.c @@ -58,7 +58,7 @@ static int of_platform_serial_setup(struct platform_device *ofdev, struct resource resource; struct device_node *np = ofdev->dev.of_node; u32 clk, spd, prop; - int ret; + int ret, irq; memset(port, 0, sizeof *port); @@ -143,21 +143,27 @@ static int of_platform_serial_setup(struct platform_device *ofdev, if (ret >= 0) port->line = ret; - port->irq = irq_of_parse_and_map(np, 0); - if (!port->irq) { - ret = -EPROBE_DEFER; - goto err_unprepare; + irq = of_irq_get(np, 0); + if (irq < 0) { + if (irq == -EPROBE_DEFER) { + ret = -EPROBE_DEFER; + goto err_unprepare; + } + /* IRQ support not mandatory */ + irq = 0; } + port->irq = irq; + info->rst = devm_reset_control_get_optional_shared(&ofdev->dev, NULL); if (IS_ERR(info->rst)) { ret = PTR_ERR(info->rst); - goto err_dispose; + goto err_unprepare; } ret = reset_control_deassert(info->rst); if (ret) - goto err_dispose; + goto err_unprepare; port->type = type; port->uartclk = clk; @@ -184,8 +190,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev, port->handle_irq = fsl8250_handle_irq; return 0; -err_dispose: - irq_dispose_mapping(port->irq); err_unprepare: clk_disable_unprepare(info->clk); err_pmruntime: -- 2.45.2