Re: [PATCH] esdhc: fix DMA_MASK to not break mx25 DMA access

[Chris Ball <cjb@laptop.org>]

Hi Wilson and Sascha,

On Tue, Jul 17 2012, Wilson & Cassie wrote:
> Patch to not set reserved bits in i.MX25 PROCTL register.  DMA stops working if those bits get set.
>
> Signed-off-by: Wilson Callan <wilson.callan at savantsystems.com>
> Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
>
> --- linux-3.4.4/drivers/mmc/host/sdhci-esdhc-imx.c.orig	2012-07-04 13:58:16.239979741 -0400
> +++ linux-3.4.4/drivers/mmc/host/sdhci-esdhc-imx.c	2012-07-04 14:34:38.939949292 -0400
> @@ -310,8 +310,10 @@ static void esdhc_writeb_le(struct sdhci
>  				SDHCI_CTRL_D3CD);
>  		/* ensure the endianess */
>  		new_val |= ESDHC_HOST_CONTROL_LE;
> -		/* DMA mode bits are shifted */
> -		new_val |= (val & SDHCI_CTRL_DMA_MASK) << 5;
> +		if (!is_imx25_esdhc(imx_data)) { // bits 8&9 are reserved on mx25
> +			/* DMA mode bits are shifted */
> +			new_val |= (val & SDHCI_CTRL_DMA_MASK) << 5;
> +		}
>  
>  		esdhc_clrset_le(host, 0xffff, new_val, reg);
>  		return;

This patch broke the imx build.  Please test patches before submitting them.

  CC      drivers/mmc/host/sdhci-esdhc-imx.o
/home/cjb/git/mmc/drivers/mmc/host/sdhci-esdhc-imx.c: In function ‘esdhc_writeb_le’:
/home/cjb/git/mmc/drivers/mmc/host/sdhci-esdhc-imx.c:319:23: error: ‘imx_data’ undeclared (first use in this function)

Fixed by:

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-i
index 6175577..e23f813 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -299,6 +299,8 @@ static void esdhc_writew_le(struct sdhci_host *host, u16 val
 
 static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
 {
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct pltfm_imx_data *imx_data = pltfm_host->priv;
        u32 new_val;
 
        switch (reg) {

And pushed out to mmc-next as part of the original patch.

- Chris.
-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child