Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752782Ab3EMFEi (ORCPT ); Mon, 13 May 2013 01:04:38 -0400 Received: from mail-oa0-f44.google.com ([209.85.219.44]:35048 "EHLO mail-oa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013Ab3EMFEh (ORCPT ); Mon, 13 May 2013 01:04:37 -0400 MIME-Version: 1.0 In-Reply-To: References: <1367803801-17111-1-git-send-email-chao.xie@marvell.com> <1367803801-17111-4-git-send-email-chao.xie@marvell.com> Date: Mon, 13 May 2013 13:04:36 +0800 Message-ID: Subject: Re: [PATCH V4 3/3] pwm: pxa: add device tree support From: Chao Xie To: Eric Miao Cc: Chao Xie , Thierry Reding , linux-kernel Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3145 Lines: 87 >> + const struct of_device_id *of_id = >> + of_match_device(pxa_pwm_of_match, &pdev->dev); >> + unsigned int npwm; >> + >> + if (!of_id) >> + return -ENODEV; >> + >> + npwm = (unsigned int)of_id->data; >> + pwm->chip.npwm = (npwm & HAS_SECONDARY_PWM) ? 2 : 1; >> + >> + return 0; >> +} >> + >> static int pwm_probe(struct platform_device *pdev) >> { >> const struct platform_device_id *id = platform_get_device_id(pdev); >> @@ -144,7 +180,6 @@ static int pwm_probe(struct platform_device *pdev) >> pwm->chip.dev = &pdev->dev; >> pwm->chip.ops = &pxa_pwm_ops; >> pwm->chip.base = -1; >> - pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1; >> >> r = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> if (r == NULL) { >> @@ -156,6 +191,20 @@ static int pwm_probe(struct platform_device *pdev) >> if (IS_ERR(pwm->mmio_base)) >> return PTR_ERR(pwm->mmio_base); >> >> + if (!id) { >> + if (IS_ENABLED(CONFIG_OF)) >> + ret = pxa_pwm_parse_data_dt(pdev, pwm); >> + else >> + ret = -ENODEV; >> + } else { >> + pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1; >> + } > > ^^ braces not necessarily here, and I'm not really sure if we should check > CONFIG_OF firstly, and leave the platform_device_id thing as a legacy > fall back, what do you think? > > if (IS_ENABLED(CONFIG_OF)) { > ... > } else { > const struct platform_device_id *id = platform_get_device_id(...); > ... > } > it has some reasons. You ways works for 1. PWM defined in DT configuration file and CONFIG_OF is defined 2. CONFIG_OF is not defined. If COFNIG_OF is defined, but PWM is not defined in device tree configuration file. The device can still match the driver is the id_table is matched or name is matched. So I covered addtional situation 1. PWM is not defined in DT configuration file but CONFIG_OF is defined. So i keep the possiblility that event CONFIG_OF is defined, but PWM is not defined in DT file, and we still can use old way to probe the device. >> + >> + if (ret) { >> + dev_err(&pdev->dev, "failed to parse data from device id\n"); >> + return ret; >> + } >> + >> ret = pwmchip_add(&pwm->chip); >> if (ret < 0) { >> dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); >> @@ -181,6 +230,7 @@ static struct platform_driver pwm_driver = { >> .driver = { >> .name = "pxa25x-pwm", >> .owner = THIS_MODULE, >> + .of_match_table = pxa_pwm_of_match, >> }, >> .probe = pwm_probe, >> .remove = pwm_remove, >> -- >> 1.7.4.1 >> -- 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/