From patchwork Tue Nov 11 03:20:23 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Frank Rowand X-Patchwork-Id: 5270331 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id B82039F2F1 for ; Tue, 11 Nov 2014 03:24:55 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D38E820155 for ; Tue, 11 Nov 2014 03:24:54 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EB2DE20136 for ; Tue, 11 Nov 2014 03:24:53 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xo20i-0002kz-46; Tue, 11 Nov 2014 03:20:52 +0000 Received: from mail-pa0-x22d.google.com ([2607:f8b0:400e:c03::22d]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xo20e-0002jr-Qv for linux-arm-kernel@lists.infradead.org; Tue, 11 Nov 2014 03:20:49 +0000 Received: by mail-pa0-f45.google.com with SMTP id lf10so9704420pab.32 for ; Mon, 10 Nov 2014 19:20:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:reply-to:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; bh=4oxoZJpKIy5DVF2h52iVZvwz7h2280rFTNkfD5GImos=; b=iBtKz8QCWleXYeb6f46SvVEEH+UBuX4LUz3QJvuNSgpjaATK4YcAWgpu10VHZbeDpR 3iNJdzyCKyVrzofrQ5MSu/OqQ9T6FH82baFz/49A7lwmkktcaPQ4tk30582g8K9sK2yV WJai4zeN2SQNhwYJR5SIRZhTsPN4cbzEqxvVmL0ULFugILC/I8VSGxM496uYjw/7C2K9 B+Imj+gYFGlalnXbB6WaEDQ/GN6gEvTZhIj4oA+ivPMeUboCjpriNW/A3YPezusijqrw m4JzlPlLZ6H1jX5yHlYLQxzgF/CF79iCStvAuLeWQ1Fzn2KWuz4BmHz+JIEuezqy0cKS v+Kw== X-Received: by 10.66.241.239 with SMTP id wl15mr37730583pac.15.1415676026250; Mon, 10 Nov 2014 19:20:26 -0800 (PST) Received: from [192.168.1.62] (c-76-21-77-187.hsd1.ca.comcast.net. [76.21.77.187]) by mx.google.com with ESMTPSA id dl1sm17839802pbc.16.2014.11.10.19.20.23 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 10 Nov 2014 19:20:25 -0800 (PST) Message-ID: <54618077.9000108@gmail.com> Date: Mon, 10 Nov 2014 19:20:23 -0800 From: Frank Rowand User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Stephen Boyd Subject: Re: [PATCH] tty: serial: msm_serial: Use DT aliases References: <1414024381-12204-1-git-send-email-sboyd@codeaurora.org> <5461150B.2010907@codeaurora.org> <54616CB3.5000405@gmail.com> <54616F74.5010408@codeaurora.org> In-Reply-To: <54616F74.5010408@codeaurora.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20141110_192048_950300_DDF46EB2 X-CRM114-Status: GOOD ( 17.63 ) X-Spam-Score: -0.8 (/) Cc: Arnd Bergmann , Kevin Hilman , Greg Kroah-Hartman , Tyler Baker , lkml , linux-serial@vger.kernel.org, linux-arm-msm , Olof Johansson , "linux-arm-kernel@lists.infradead.org" X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: frowand.list@gmail.com Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-3.0 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 11/10/2014 6:07 PM, Stephen Boyd wrote: > On 11/10/2014 05:56 PM, Frank Rowand wrote: >> On 11/10/2014 11:42 AM, Stephen Boyd wrote: >>> diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c >>> index 09364dd8cf3a..d1bc6b6cbc70 100644 >>> --- a/drivers/tty/serial/msm_serial.c >>> +++ b/drivers/tty/serial/msm_serial.c >>> @@ -1046,14 +1046,14 @@ static int msm_serial_probe(struct platform_device *pdev) >>> const struct of_device_id *id; >>> int irq, line; >>> >>> - if (pdev->id == -1) >>> - pdev->id = atomic_inc_return(&msm_uart_next_id) - 1; >>> - >>> if (pdev->dev.of_node) >>> line = of_alias_get_id(pdev->dev.of_node, "serial"); >>> else >>> line = pdev->id; >>> >>> + if (line < 0) >>> + line = atomic_inc_return(&msm_uart_next_id) - 1; >>> + >>> if (unlikely(line < 0 || line >= UART_NR)) >> Then this original check for "line < 0" can also be removed. >> >> > > Well this matches what was there before. It would do atomic_inc_return > if the line was negative and then still check for a negative value. I > don't mind removing it though. Perhaps we should use an ida?: > OK, you are right. If (pdev->id < -1) and (!pdev->dev.of_node) then the check is still needed. You could use an ida. Some drivers use a bit map. I really don't think this should become a complicated algorithm though. If the rule is that either all UARTS have an alias, or no UART has an alias, then I think the patch could be something like the following. This combines your original patch, plus your fix patch, plus making the aliases all or nothing. Not tested, not even compiled. What do you think? Index: linux/drivers/tty/serial/msm_serial.c =================================================================== --- linux.orig/drivers/tty/serial/msm_serial.c +++ linux/drivers/tty/serial/msm_serial.c @@ -1044,17 +1044,28 @@ static int msm_serial_probe(struct platf struct resource *resource; struct uart_port *port; const struct of_device_id *id; - int irq; + int irq, line; + static int no_prev_alias = 1; - if (pdev->id == -1) - pdev->id = atomic_inc_return(&msm_uart_next_id) - 1; + if (pdev->dev.of_node) { + line = of_alias_get_id(pdev->dev.of_node, "serial"); + if (line < 0 && no_prev_alias) + line = atomic_inc_return(&msm_uart_next_id) - 1; + else + no_prev_alias = 0; + } else { + if (pdev->id < 0 && no_prev_alias) + line = atomic_inc_return(&msm_uart_next_id) - 1; + else + line = pdev->id; + } - if (unlikely(pdev->id < 0 || pdev->id >= UART_NR)) + if (unlikely(line < 0 || line >= UART_NR)) return -ENXIO; - dev_info(&pdev->dev, "msm_serial: detected port #%d\n", pdev->id); + dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line); - port = get_port_from_line(pdev->id); + port = get_port_from_line(line); port->dev = &pdev->dev; msm_port = UART_TO_MSM(port);