From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jaehoon Chung Subject: Re: [PATCH v2 1/4] dt: bindings: mmc: Document the practice of using subnodes for slots Date: Tue, 03 Jun 2014 10:13:26 +0900 Message-ID: <538D2136.5030008@samsung.com> References: <1401563014-13856-1-git-send-email-hdegoede@redhat.com> <1401563014-13856-2-git-send-email-hdegoede@redhat.com> <538AF124.9040106@redhat.com> <538C3812.9060705@samsung.com> <538C39CA.4020301@samsung.com> Reply-To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-reply-to: List-Post: , List-Help: , List-Archive: Sender: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org List-Subscribe: , List-Unsubscribe: , To: Ulf Hansson , Jaehoon Chung Cc: Hans de Goede , Olof Johansson , linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Chris Ball , Sascha Hauer , Maxime Ripard , Arend van Spriel , Chen-Yu Tsai , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-mmc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , devicetree , Seungwon Jeon List-Id: linux-mmc@vger.kernel.org + Seungwon Jeon On 06/02/2014 05:52 PM, Ulf Hansson wrote: > On 2 June 2014 10:46, Jaehoon Chung wrote: >> On 06/02/2014 05:38 PM, Jaehoon Chung wrote: >>> On 06/02/2014 05:29 PM, Ulf Hansson wrote: >>>> On 1 June 2014 11:23, Hans de Goede wrote: >>>>> Hi, >>>>> >>>>> >>>>> On 05/31/2014 10:13 PM, Olof Johansson wrote: >>>>>> >>>>>> On Sat, May 31, 2014 at 12:03 PM, Hans de Goede >>>>>> wrote: >>>>>>> >>>>>>> The following existing MMC host controller bindings use slot subnodes: >>>>>>> >>>>>>> Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/k3-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/socfpga-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/atmel-hsmci.txt >>>>>>> Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt >>>>>>> >>>>>>> This commit documents this practice in the standard mmc bindings >>>>>>> documentation. >>>>>>> >>>>>>> Signed-off-by: Hans de Goede >>>>>> >>>>>> >>>>>> There are today only two drivers that use this kind of binding, dw_mmc >>>>>> and the at91 one. >>>>> >>>>> >>>>> Correct. >>>>> >>>>> >>>>>> Neither seems to actually ever have been used with >>>>>> more than one slot. I doubt anyone building an exynos-based system >>>>>> will ever do a multi-slot solution, and it seems that the at91 driver >>>>>> doesn't actually handle more than one slot. >>>>>> >>>>>> I'm personally not that excited about complicating the bindings by >>>>>> opening up for this -- I would rather work towards removing the >>>>>> concept of slots if it's one of those things that are going to remain >>>>>> unused. We have actually been talking about reworking the dw_mmc >>>>>> binding to remove the slot concept (and simplify the driver by doing >>>>>> so). >>>>> >>>>> >>>>> I'm fine with removing the slot subnode, I added it because of it being >>>>> brought up in the powerup sequence discussion. I explicitly asked there >>>>> if adding such a subnode level was seen as desirable but nobody >>>>> answered :| >>>>> >>>>> Anyways, either way works for me. I can do a v3 dropping the slot subnode >>>>> level again. I would really like to move forward with a decision on how-to >>>>> represent non probable info for sdio devices in device nodes. So do you >>>>> have any other remarks other then that the slot subnode should be dropped ? >>>>> And if not can you please review and ack (*) v3 of this patch-set once >>>>> I've send it? >>>>> >>>>> Chris Ball and Ulf Hansson, what is your take on this, are you willing to >>>>> take this patch set? And do you want it with or without the slot subnodes ? >>>> >>>> I certainly appreciate you working actively on this Hans, I will look >>>> into the patchset as soon as I can. >>>> >>>> I share Olof's view about the slot nodes, we must not add DT bindings >>>> that isn't really needed. >>>> >>>> Regarding the slot subnodes; Jaehoon Chung recently posted a patchset >>>> for adding the parsing of it, intended for dwmmc. I withdraw my ack >>>> for it, and let's try to go in the other direction instead. >>>> >>>> [PATCHv3 0/4] mmc: fixed the mmc_of_parse for dwmmc. >>>> >>>> Thus I suggest we should clean-up host drivers to support only one >>>> card per host, and entirely skip the slot concept. >>> >>> Well, almost platform is used the only one card per host, although some controller is supported the slot concept. >>> But we don't know that controller should be used the multi slot per host, in future. >>> So I think we can't skip the slot concept. >> If we need to change the dw-mmc controller, let me know, plz. >> I want to fix this problem before release the 3.16. >> Actually, i think it can remove the subnode, if ensure not to use multi-slot at dwmmc. > > That seems like the best approach. Please try to remove the subnodes > and make use of mmc_of_parse, as is. > > Kind regards > Uffe > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > From mboxrd@z Thu Jan 1 00:00:00 1970 From: jh80.chung@samsung.com (Jaehoon Chung) Date: Tue, 03 Jun 2014 10:13:26 +0900 Subject: [linux-sunxi] [PATCH v2 1/4] dt: bindings: mmc: Document the practice of using subnodes for slots In-Reply-To: References: <1401563014-13856-1-git-send-email-hdegoede@redhat.com> <1401563014-13856-2-git-send-email-hdegoede@redhat.com> <538AF124.9040106@redhat.com> <538C3812.9060705@samsung.com> <538C39CA.4020301@samsung.com> Message-ID: <538D2136.5030008@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org + Seungwon Jeon On 06/02/2014 05:52 PM, Ulf Hansson wrote: > On 2 June 2014 10:46, Jaehoon Chung wrote: >> On 06/02/2014 05:38 PM, Jaehoon Chung wrote: >>> On 06/02/2014 05:29 PM, Ulf Hansson wrote: >>>> On 1 June 2014 11:23, Hans de Goede wrote: >>>>> Hi, >>>>> >>>>> >>>>> On 05/31/2014 10:13 PM, Olof Johansson wrote: >>>>>> >>>>>> On Sat, May 31, 2014 at 12:03 PM, Hans de Goede >>>>>> wrote: >>>>>>> >>>>>>> The following existing MMC host controller bindings use slot subnodes: >>>>>>> >>>>>>> Documentation/devicetree/bindings/mmc/synopsys-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/k3-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/exynos-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/socfpga-dw-mshc.txt >>>>>>> Documentation/devicetree/bindings/mmc/atmel-hsmci.txt >>>>>>> Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.txt >>>>>>> >>>>>>> This commit documents this practice in the standard mmc bindings >>>>>>> documentation. >>>>>>> >>>>>>> Signed-off-by: Hans de Goede >>>>>> >>>>>> >>>>>> There are today only two drivers that use this kind of binding, dw_mmc >>>>>> and the at91 one. >>>>> >>>>> >>>>> Correct. >>>>> >>>>> >>>>>> Neither seems to actually ever have been used with >>>>>> more than one slot. I doubt anyone building an exynos-based system >>>>>> will ever do a multi-slot solution, and it seems that the at91 driver >>>>>> doesn't actually handle more than one slot. >>>>>> >>>>>> I'm personally not that excited about complicating the bindings by >>>>>> opening up for this -- I would rather work towards removing the >>>>>> concept of slots if it's one of those things that are going to remain >>>>>> unused. We have actually been talking about reworking the dw_mmc >>>>>> binding to remove the slot concept (and simplify the driver by doing >>>>>> so). >>>>> >>>>> >>>>> I'm fine with removing the slot subnode, I added it because of it being >>>>> brought up in the powerup sequence discussion. I explicitly asked there >>>>> if adding such a subnode level was seen as desirable but nobody >>>>> answered :| >>>>> >>>>> Anyways, either way works for me. I can do a v3 dropping the slot subnode >>>>> level again. I would really like to move forward with a decision on how-to >>>>> represent non probable info for sdio devices in device nodes. So do you >>>>> have any other remarks other then that the slot subnode should be dropped ? >>>>> And if not can you please review and ack (*) v3 of this patch-set once >>>>> I've send it? >>>>> >>>>> Chris Ball and Ulf Hansson, what is your take on this, are you willing to >>>>> take this patch set? And do you want it with or without the slot subnodes ? >>>> >>>> I certainly appreciate you working actively on this Hans, I will look >>>> into the patchset as soon as I can. >>>> >>>> I share Olof's view about the slot nodes, we must not add DT bindings >>>> that isn't really needed. >>>> >>>> Regarding the slot subnodes; Jaehoon Chung recently posted a patchset >>>> for adding the parsing of it, intended for dwmmc. I withdraw my ack >>>> for it, and let's try to go in the other direction instead. >>>> >>>> [PATCHv3 0/4] mmc: fixed the mmc_of_parse for dwmmc. >>>> >>>> Thus I suggest we should clean-up host drivers to support only one >>>> card per host, and entirely skip the slot concept. >>> >>> Well, almost platform is used the only one card per host, although some controller is supported the slot concept. >>> But we don't know that controller should be used the multi slot per host, in future. >>> So I think we can't skip the slot concept. >> If we need to change the dw-mmc controller, let me know, plz. >> I want to fix this problem before release the 3.16. >> Actually, i think it can remove the subnode, if ensure not to use multi-slot at dwmmc. > > That seems like the best approach. Please try to remove the subnodes > and make use of mmc_of_parse, as is. > > Kind regards > Uffe > -- > To unsubscribe from this list: send the line "unsubscribe linux-mmc" in > the body of a message to majordomo at vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >