From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tomasz Figa Subject: Re: [PATCH 1/2 v3] spi: s3c64xx: use "cs-gpios" from spi node instead of "cs-gpio" Date: Wed, 11 Jun 2014 19:50:51 +0200 Message-ID: <539896FB.4050702@gmail.com> References: <1402468318-7342-1-git-send-email-ch.naveen@samsung.com> <539839D6.1050305@collabora.co.uk> <5398918F.4060800@collabora.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5398918F.4060800@collabora.co.uk> Sender: linux-samsung-soc-owner@vger.kernel.org To: Javier Martinez Canillas , Naveen Krishna Ch Cc: Naveen Krishna Chatradhi , "linux-arm-kernel@lists.infradead.org" , spi-devel-general@lists.sourceforge.net, "linux-samsung-soc@vger.kernel.org" , broonie@kernel.org, grant.likely@secretlab.ca, jaswinder.singh@linaro.org, Kukjin Kim , cpgs@samsung.com, devicetree@vger.kernel.org, Doug Anderson , Tomasz Figa List-Id: devicetree@vger.kernel.org On 11.06.2014 19:27, Javier Martinez Canillas wrote: > On 06/11/2014 01:38 PM, Naveen Krishna Ch wrote: >> On 11 June 2014 16:43, Javier Martinez Canillas >> wrote: >>> On 06/11/2014 08:31 AM, Naveen Krishna Chatradhi wrote: [snip] >>> >>>> return ERR_PTR(-EINVAL); >>>> } >>>> + cs->line = spi->cs_gpio; >>>> >>> >>> I wonder why are you keeping cs->line? AFAICT it's only used in >>> s3c64xx_spi_setup() to request the GPIO and since you get the struct spi_device >>> pointer as a parameter then you can just use spi->s_gpio instead. >> I'm trying not to touch the non-DT part of the code. >> >> struct s3c64xx_spi_csinfo *cs = spi->controller_data; >> >> This will update the cs->line and cs->fb_delay in case of non-DT. > > I see, then I prefer the opposite and do something like this on s3c64xx_spi_probe(): > > if (!pdev->dev.of_node) > spi->cs_gpio = cs->line; Hmm, as far as I understand, spi here is spi_device, not spi_master. I don't think you have access to SPI devices on your bus in controller probe(). What I think could work is reworking the driver to: - in DT case, don't do anything in the driver about the GPIO chip select, because it will be handled automatically by the core. - in non-DT case, in s3c64xx_spi_setup(), just take the GPIO pin from s3c64xx_spi_csinfo struct passed through spi->controller_data, request it and save it to spi->cs_gpio, - in non-DT case, in s3c64xx_spi_cleanup(), free the GPIO requested in s3c64xx_spi_setup() and set spi->cs_gpio to -ENOENT (as done initially in spi_alloc_device()). Best regards, Tomasz