Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032223AbbKEJQb (ORCPT ); Thu, 5 Nov 2015 04:16:31 -0500 Received: from mail-yk0-f173.google.com ([209.85.160.173]:34703 "EHLO mail-yk0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030926AbbKEJQR (ORCPT ); Thu, 5 Nov 2015 04:16:17 -0500 MIME-Version: 1.0 In-Reply-To: <1446702633-14019-1-git-send-email-drinkcat@chromium.org> References: <1446702633-14019-1-git-send-email-drinkcat@chromium.org> Date: Thu, 5 Nov 2015 11:16:16 +0200 Message-ID: Subject: Re: [PATCH] spi: mediatek: single device does not require cs_gpios From: Andy Shevchenko To: Nicolas Boichat Cc: Mark Brown , Leilk Liu , Matthias Brugger , linux-spi@vger.kernel.org, "linux-kernel@vger.kernel.org" , linux-arm Mailing List , linux-mediatek@lists.infradead.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3377 Lines: 83 On Thu, Nov 5, 2015 at 7:50 AM, Nicolas Boichat wrote: > When only one device is present, it is not necessary to specify > cs_gpios, as the CS line can be controlled by the hardware > module. > > Without this patch, older device tree bindings used before > 37457607 "spi: mediatek: mt8173 spi multiple devices support" > would cause a panic on boot. This fixes the crash, and > re-introduces backward compatibility. > > Signed-off-by: Nicolas Boichat > --- > > Applies on top of broonie/spi.git topic/mtk. Thanks! > > drivers/spi/spi-mt65xx.c | 26 ++++++++++++++++++-------- > 1 file changed, 18 insertions(+), 8 deletions(-) > > diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c > index 563954a..f694031 100644 > --- a/drivers/spi/spi-mt65xx.c > +++ b/drivers/spi/spi-mt65xx.c > @@ -410,7 +410,7 @@ static int mtk_spi_setup(struct spi_device *spi) > if (!spi->controller_data) > spi->controller_data = (void *)&mtk_default_chip_info; > > - if (mdata->dev_comp->need_pad_sel) > + if (mdata->dev_comp->need_pad_sel && spi->cs_gpio >= 0) gpio_is_valid() ? > gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH)); > > return 0; > @@ -632,13 +632,23 @@ static int mtk_spi_probe(struct platform_device *pdev) > goto err_put_master; > } > > - for (i = 0; i < master->num_chipselect; i++) { > - ret = devm_gpio_request(&pdev->dev, master->cs_gpios[i], > - dev_name(&pdev->dev)); > - if (ret) { > - dev_err(&pdev->dev, > - "can't get CS GPIO %i\n", i); > - goto err_put_master; > + if (!master->cs_gpios && master->num_chipselect > 1) { > + dev_err(&pdev->dev, > + "cs_gpios not specified and num_chipselect > 1\n"); > + ret = -EINVAL; > + goto err_put_master; > + } > + > + if (master->cs_gpios) { > + for (i = 0; i < master->num_chipselect; i++) { > + ret = devm_gpio_request(&pdev->dev, > + master->cs_gpios[i], > + dev_name(&pdev->dev)); > + if (ret) { > + dev_err(&pdev->dev, > + "can't get CS GPIO %i\n", i); > + goto err_put_master; > + } > } > } > } > -- > 2.6.0.rc2.230.g3dd15c0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-spi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- With Best Regards, Andy Shevchenko -- 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/