From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755031Ab3COTsN (ORCPT ); Fri, 15 Mar 2013 15:48:13 -0400 Received: from mail.free-electrons.com ([94.23.35.102]:56601 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753522Ab3COTsM (ORCPT ); Fri, 15 Mar 2013 15:48:12 -0400 Message-ID: <51437AF9.2050007@free-electrons.com> Date: Fri, 15 Mar 2013 20:48:09 +0100 From: Maxime Ripard User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: Heikki Krogerus CC: linux-arm-kernel@lists.infradead.org, kevin@allwinnertech.com, sunny@allwinnertech.com, shuge@allwinnertech.com, =?ISO-8859-1?Q?Emilio_?= =?ISO-8859-1?Q?L=F3pez?= , Greg Kroah-Hartman , Jiri Slaby , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/6] serial: 8250_dw: add support for clocks property when using DeviceTree References: <1362694460-1919-1-git-send-email-maxime.ripard@free-electrons.com> <1362694460-1919-2-git-send-email-maxime.ripard@free-electrons.com> <20130315125615.GA27560@xps8300> In-Reply-To: <20130315125615.GA27560@xps8300> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Heikki Le 15/03/2013 13:56, Heikki Krogerus a écrit : >> @@ -137,8 +140,15 @@ static int dw8250_probe_of(struct uart_port *p) >> p->regshift = val; >> >> if (of_property_read_u32(np, "clock-frequency", &val)) { >> - dev_err(p->dev, "no clock-frequency property set\n"); >> - return -EINVAL; >> + /* Get clk rate through clk driver if present */ >> + data->clk = clk_get(p->dev, NULL); >> + if (IS_ERR(data->clk)) { >> + dev_err(p->dev, "clk or clock-frequency not defined\n"); >> + return -EINVAL; >> + } >> + >> + clk_prepare_enable(data->clk); >> + val = clk_get_rate(data->clk); > > Don't get the clk here.. > >> } >> p->uartclk = val; >> >> @@ -300,6 +310,12 @@ static int dw8250_probe(struct platform_device *pdev) > > Get it here so it is then handled for also others besides DT users. > And prefer devm_clk_get(). Something like this: > > ... > uart.port.membase = ioremap(regs->start, resource_size(regs)); > if (!uart.port.membase) > return -ENOMEM; > > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->clk = devm_clk_get(&pdev->dev, NULL); > + clk_prepare_enable(data->clk); > + > uart.port.iotype = UPIO_MEM; > uart.port.serial_in = dw8250_serial_in; > uart.port.serial_out = dw8250_serial_out; > + uart.port.private_data = data; > + uart.port.uartclk = clk_get_rate(data->clk); > > dw8250_setup_port(&uart); > ... > > Then in dw8250_probe_of() you need to use the "clock-frequency" > property only when p->uartclk is 0. Thanks for your feedback. Emilio made a new version of this patch, I'll send it soon. Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com