From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756562AbbAHPuI (ORCPT ); Thu, 8 Jan 2015 10:50:08 -0500 Received: from relay1.mentorg.com ([192.94.38.131]:34212 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755953AbbAHPuG (ORCPT ); Thu, 8 Jan 2015 10:50:06 -0500 Message-ID: <54AEA727.40100@mentor.com> Date: Thu, 8 Jan 2015 17:49:59 +0200 From: Vladimir Zapolskiy User-Agent: Mozilla/5.0 (X11; Linux i686; rv:31.0) Gecko/20100101 Icedove/31.0 MIME-Version: 1.0 To: Ezequiel Garcia , Andrew Bresticker , Thierry Reding , James Hartley , Arnd Bergmann , Greg Kroah-Hartman CC: , , , Naidu Tellapati , Sai Masarapu Subject: Re: [PATCH v7 1/4] pwm: Imagination Technologies PWM DAC driver References: <1420651215-3836-1-git-send-email-ezequiel.garcia@imgtec.com> <1420651215-3836-2-git-send-email-ezequiel.garcia@imgtec.com> In-Reply-To: <1420651215-3836-2-git-send-email-ezequiel.garcia@imgtec.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [137.202.0.76] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ezequiel, On 07.01.2015 19:20, Ezequiel Garcia wrote: > From: Naidu Tellapati > > The Pistachio SOC from Imagination Technologies includes a Pulse Width > Modulation DAC which produces 1 to 4 digital bit-outputs which represent > digital waveforms. These PWM outputs are primarily in charge of controlling > backlight LED devices. > > Reviewed-by: Andrew Bresticker > Signed-off-by: Naidu Tellapati > Signed-off-by: Sai Masarapu > Signed-off-by: Ezequiel Garcia > --- > drivers/pwm/Kconfig | 13 +++ > drivers/pwm/Makefile | 1 + > drivers/pwm/pwm-img.c | 250 ++++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 264 insertions(+) > create mode 100644 drivers/pwm/pwm-img.c > [snip] > +static int img_pwm_probe(struct platform_device *pdev) > +{ > + int ret; > + struct resource *res; > + struct img_pwm_chip *pwm; > + > + pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL); > + if (!pwm) > + return -ENOMEM; > + > + pwm->dev = &pdev->dev; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + pwm->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(pwm->base)) > + return PTR_ERR(pwm->base); > + > + pwm->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, > + "img,cr-periph"); > + if (IS_ERR(pwm->periph_regs)) > + return PTR_ERR(pwm->periph_regs); > + > + pwm->sys_clk = devm_clk_get(&pdev->dev, "sys"); > + if (IS_ERR(pwm->sys_clk)) { > + dev_err(&pdev->dev, "failed to get system clock\n"); > + return PTR_ERR(pwm->sys_clk); > + } > + > + pwm->pwm_clk = devm_clk_get(&pdev->dev, "pwm"); > + if (IS_ERR(pwm->pwm_clk)) { > + dev_err(&pdev->dev, "failed to get pwm clock\n"); > + return PTR_ERR(pwm->pwm_clk); > + } > + > + ret = clk_prepare_enable(pwm->sys_clk); > + if (ret < 0) { > + dev_err(&pdev->dev, "could not prepare or enable sys clock\n"); > + return ret; > + } > + > + ret = clk_prepare_enable(pwm->pwm_clk); > + if (ret < 0) { > + dev_err(&pdev->dev, "could not prepare or enable pwm clock\n"); > + goto disable_sysclk; > + } > + > + pwm->chip.dev = &pdev->dev; > + pwm->chip.ops = &img_pwm_ops; > + pwm->chip.base = -1; > + pwm->chip.npwm = 4; > + > + ret = pwmchip_add(&pwm->chip); > + if (ret < 0) { > + dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret); > + goto disable_pwmclk; > + } > + > + platform_set_drvdata(pdev, pwm); > + > +disable_pwmclk: > + clk_disable_unprepare(pwm->pwm_clk); > +disable_sysclk: > + clk_disable_unprepare(pwm->sys_clk); > + > + return 0; return ret on error paths? Also should you reenable sys and pwm clocks after successful driver registration? > +} > + -- With best wishes, Vladimir