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* Pinmuxing and SDHC speeds on sdhci-esdhc-imx
@ 2018-10-09 13:38 Adam Ford
  2018-10-10  3:28 ` Bough Chen
  0 siblings, 1 reply; 2+ messages in thread
From: Adam Ford @ 2018-10-09 13:38 UTC (permalink / raw)
  To: linux-mmc, Linux Kernel Mailing List, aisheng.dong, haibo.chen,
	Fabio Estevam

I have a question regarding the pinstate and the corresponding uhs_signaling.

The uhs_signaling shows a variety of timing options,

 MMC_TIMING_UHS_SDR12,  MMC_TIMING_UHS_SDR25:,  MMC_TIMING_UHS_SDR50,
MMC_TIMING_UHS_SDR104,  MMC_TIMING_MMC_HS200,  MMC_TIMING_UHS_DDR50,
MMC_TIMING_MMC_DDR52,  MMC_TIMING_MMC_HS400, and MMC_TIMING_LEGACY

However the esdhc_change_pinstate function only lists
MMC_TIMING_UHS_SDR50, MMC_TIMING_UHS_DDR50, MMC_TIMING_UHS_SDR104,
MMC_TIMING_MMC_HS200, and MMC_TIMING_MMC_HS40, and a defaut.

From what I can tell, this means that  MMC_TIMING_MMC_DDR52 uses the
default pinmux.  I am wondering if it should use pins_100mhz.  We have
an eMMC part that we want to operate at this point and it seems like
it missing.  If so, I can submit a patch.

It also seems like that SDR12, SDR25 use the default.  I assume this is OK.

adam

^ permalink raw reply	[flat|nested] 2+ messages in thread

* RE: Pinmuxing and SDHC speeds on sdhci-esdhc-imx
  2018-10-09 13:38 Pinmuxing and SDHC speeds on sdhci-esdhc-imx Adam Ford
@ 2018-10-10  3:28 ` Bough Chen
  0 siblings, 0 replies; 2+ messages in thread
From: Bough Chen @ 2018-10-10  3:28 UTC (permalink / raw)
  To: Adam Ford, linux-mmc, Linux Kernel Mailing List, A.s. Dong,
	haibo.chen, Fabio Estevam

Hi Adam

Yes, MMC_DDR52 can use pins_100mhz. You can do that, thanks!

Best Regards
Bough Chen

> -----Original Message-----
> From: linux-mmc-owner@vger.kernel.org
> [mailto:linux-mmc-owner@vger.kernel.org] On Behalf Of Adam Ford
> Sent: 2018年10月9日 21:38
> To: linux-mmc@vger.kernel.org; Linux Kernel Mailing List
> <linux-kernel@vger.kernel.org>; A.s. Dong <aisheng.dong@nxp.com>;
> haibo.chen@freescale.com; Fabio Estevam <fabio.estevam@nxp.com>
> Subject: Pinmuxing and SDHC speeds on sdhci-esdhc-imx
> 
> I have a question regarding the pinstate and the corresponding uhs_signaling.
> 
> The uhs_signaling shows a variety of timing options,
> 
>  MMC_TIMING_UHS_SDR12,  MMC_TIMING_UHS_SDR25:,
> MMC_TIMING_UHS_SDR50, MMC_TIMING_UHS_SDR104,
> MMC_TIMING_MMC_HS200,  MMC_TIMING_UHS_DDR50,
> MMC_TIMING_MMC_DDR52,  MMC_TIMING_MMC_HS400, and
> MMC_TIMING_LEGACY
> 
> However the esdhc_change_pinstate function only lists
> MMC_TIMING_UHS_SDR50, MMC_TIMING_UHS_DDR50,
> MMC_TIMING_UHS_SDR104, MMC_TIMING_MMC_HS200, and
> MMC_TIMING_MMC_HS40, and a defaut.
> 
> From what I can tell, this means that  MMC_TIMING_MMC_DDR52 uses the
> default pinmux.  I am wondering if it should use pins_100mhz.  We have an
> eMMC part that we want to operate at this point and it seems like it missing.
> If so, I can submit a patch.
> 
> It also seems like that SDR12, SDR25 use the default.  I assume this is OK.
> 
> adam

^ permalink raw reply	[flat|nested] 2+ messages in thread

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2018-10-09 13:38 Pinmuxing and SDHC speeds on sdhci-esdhc-imx Adam Ford
2018-10-10  3:28 ` Bough Chen

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