From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Subject: [PATCH v2] backlight: pwm: reject legacy pwm request for device defined in dt Date: Mon, 12 Oct 2015 15:29:03 +0300 Message-ID: <1444652943-19712-1-git-send-email-vladimir_zapolskiy@mentor.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from relay1.mentorg.com ([192.94.38.131]:40822 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751134AbbJLMab (ORCPT ); Mon, 12 Oct 2015 08:30:31 -0400 Sender: linux-pwm-owner@vger.kernel.org List-Id: linux-pwm@vger.kernel.org To: Thierry Reding , Lee Jones , Jingoo Han Cc: Nicolas Ferre , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org Platform PWM backlight data provided by board's device tree should be complete enough to successfully request a pwm device using pwm_get() API. This change fixes a bug, when an arbitrary (first found) PWM is connected to a "pwm-backlight" compatible device, when explicit PWM device reference is not given. Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt already describes "pwms" as a required property, instead of blind selection of a potentially wrong PWM reject legacy PWM device registration request, leave legacy API only for non-dt cases. Based on initial implementation done by Dmitry Eremin-Solenikov. Reported-by: Dmitry Eremin-Solenikov Signed-off-by: Vladimir Zapolskiy Acked-by: Thierry Reding Acked-by: Lee Jones --- The change is based on lee-backlight/for-backlight-next Changes from v1 to v2: * rebased on top of Nicolas' commit 68feaca0b13 ("backlight: pwm: Handle EPROBE_DEFER while requesting the PWM") Links to previous discussions of the change: * https://patchwork.ozlabs.org/patch/483993/ * https://patchwork.ozlabs.org/patch/398849/ drivers/video/backlight/pwm_bl.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index eff379b..ae3c6b6 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -271,19 +271,18 @@ static int pwm_backlight_probe(struct platform_device *pdev) } pb->pwm = devm_pwm_get(&pdev->dev, NULL); - if (IS_ERR(pb->pwm)) { - ret = PTR_ERR(pb->pwm); - if (ret == -EPROBE_DEFER) - goto err_alloc; - + if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER + && !pdev->dev.of_node) { dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n"); pb->legacy = true; pb->pwm = pwm_request(data->pwm_id, "pwm-backlight"); - if (IS_ERR(pb->pwm)) { - dev_err(&pdev->dev, "unable to request legacy PWM\n"); - ret = PTR_ERR(pb->pwm); - goto err_alloc; - } + } + + if (IS_ERR(pb->pwm)) { + ret = PTR_ERR(pb->pwm); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "unable to request PWM\n"); + goto err_alloc; } dev_dbg(&pdev->dev, "got pwm for backlight\n"); -- 2.5.0 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Date: Mon, 12 Oct 2015 12:29:03 +0000 Subject: [PATCH v2] backlight: pwm: reject legacy pwm request for device defined in dt Message-Id: <1444652943-19712-1-git-send-email-vladimir_zapolskiy@mentor.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Thierry Reding , Lee Jones , Jingoo Han Cc: Nicolas Ferre , linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org Platform PWM backlight data provided by board's device tree should be complete enough to successfully request a pwm device using pwm_get() API. This change fixes a bug, when an arbitrary (first found) PWM is connected to a "pwm-backlight" compatible device, when explicit PWM device reference is not given. Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt already describes "pwms" as a required property, instead of blind selection of a potentially wrong PWM reject legacy PWM device registration request, leave legacy API only for non-dt cases. Based on initial implementation done by Dmitry Eremin-Solenikov. Reported-by: Dmitry Eremin-Solenikov Signed-off-by: Vladimir Zapolskiy Acked-by: Thierry Reding Acked-by: Lee Jones --- The change is based on lee-backlight/for-backlight-next Changes from v1 to v2: * rebased on top of Nicolas' commit 68feaca0b13 ("backlight: pwm: Handle EPROBE_DEFER while requesting the PWM") Links to previous discussions of the change: * https://patchwork.ozlabs.org/patch/483993/ * https://patchwork.ozlabs.org/patch/398849/ drivers/video/backlight/pwm_bl.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c index eff379b..ae3c6b6 100644 --- a/drivers/video/backlight/pwm_bl.c +++ b/drivers/video/backlight/pwm_bl.c @@ -271,19 +271,18 @@ static int pwm_backlight_probe(struct platform_device *pdev) } pb->pwm = devm_pwm_get(&pdev->dev, NULL); - if (IS_ERR(pb->pwm)) { - ret = PTR_ERR(pb->pwm); - if (ret = -EPROBE_DEFER) - goto err_alloc; - + if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER + && !pdev->dev.of_node) { dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n"); pb->legacy = true; pb->pwm = pwm_request(data->pwm_id, "pwm-backlight"); - if (IS_ERR(pb->pwm)) { - dev_err(&pdev->dev, "unable to request legacy PWM\n"); - ret = PTR_ERR(pb->pwm); - goto err_alloc; - } + } + + if (IS_ERR(pb->pwm)) { + ret = PTR_ERR(pb->pwm); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "unable to request PWM\n"); + goto err_alloc; } dev_dbg(&pdev->dev, "got pwm for backlight\n"); -- 2.5.0