Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753292AbaATJH4 (ORCPT ); Mon, 20 Jan 2014 04:07:56 -0500 Received: from mail-pa0-f43.google.com ([209.85.220.43]:47247 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753058AbaATJHL (ORCPT ); Mon, 20 Jan 2014 04:07:11 -0500 From: Tushar Behera To: linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, linux-samsung-soc@vger.kernel.org Cc: jslaby@suse.cz, gregkh@linuxfoundation.org, linux@arm.linux.org.uk, ben.dooks@codethink.co.uk, broonie@kernel.org Subject: [PATCH 2/2] serial: pl011: Move uart_register_driver call to device probe Date: Mon, 20 Jan 2014 14:32:35 +0530 Message-Id: <1390208555-27770-3-git-send-email-tushar.behera@linaro.org> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1390208555-27770-1-git-send-email-tushar.behera@linaro.org> References: <1390208555-27770-1-git-send-email-tushar.behera@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with same default major/minor numbers are included in the kernel. A typical case is observed with amba-pl011 and samsung-uart drivers. Signed-off-by: Tushar Behera --- drivers/tty/serial/amba-pl011.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index d58783d..d4eda24 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -2154,9 +2154,19 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) amba_ports[i] = uap; amba_set_drvdata(dev, uap); + + if (!amba_reg.state) { + ret = uart_register_driver(&amba_reg); + if (ret < 0) { + pr_err("Failed to register AMBA-PL011 driver\n"); + return ret; + } + } + ret = uart_add_one_port(&amba_reg, &uap->port); if (ret) { amba_ports[i] = NULL; + uart_unregister_driver(&amba_reg); pl011_dma_remove(uap); } out: @@ -2175,6 +2185,7 @@ static int pl011_remove(struct amba_device *dev) amba_ports[i] = NULL; pl011_dma_remove(uap); + uart_unregister_driver(&amba_reg); return 0; } @@ -2230,22 +2241,14 @@ static struct amba_driver pl011_driver = { static int __init pl011_init(void) { - int ret; printk(KERN_INFO "Serial: AMBA PL011 UART driver\n"); - ret = uart_register_driver(&amba_reg); - if (ret == 0) { - ret = amba_driver_register(&pl011_driver); - if (ret) - uart_unregister_driver(&amba_reg); - } - return ret; + return amba_driver_register(&pl011_driver); } static void __exit pl011_exit(void) { amba_driver_unregister(&pl011_driver); - uart_unregister_driver(&amba_reg); } /* -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/