[PATCH 116/139] mmc: sdhci-esdhc-imx: fix host version read

From: Luis Henriques
Date: Thu Feb 28 2013 - 09:57:43 EST


3.5.7.7 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Shawn Guo <shawn.guo@xxxxxxxxxx>

commit ef4d0888bb7e1b963880f086575081c3d39cad2d upstream.

When commit 95a2482 (mmc: sdhci-esdhc-imx: add basic imx6q usdhc
support) works around host version issue on imx6q, it gets the
register address fixup "reg ^= 2" lost for imx25/35/51/53 esdhc.
Thus, the controller version on these SoCs is wrongly identified
as v1 while it's actually v2.

Add the address fixup back and take a different approach to correct
imx6q host version, so that the host version read gets back to work
for all SoCs.

Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
Signed-off-by: Chris Ball <cjb@xxxxxxxxxx>
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-esdhc-imx.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index ebbe984..1dc06a6 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -237,15 +237,18 @@ static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)

static u16 esdhc_readw_le(struct sdhci_host *host, int reg)
{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct pltfm_imx_data *imx_data = pltfm_host->priv;
+
if (unlikely(reg == SDHCI_HOST_VERSION)) {
- u16 val = readw(host->ioaddr + (reg ^ 2));
- /*
- * uSDHC supports SDHCI v3.0, but it's encoded as value
- * 0x3 in host controller version register, which violates
- * SDHCI_SPEC_300 definition. Work it around here.
- */
- if ((val & SDHCI_SPEC_VER_MASK) == 3)
- return --val;
+ reg ^= 2;
+ if (is_imx6q_usdhc(imx_data)) {
+ /*
+ * The usdhc register returns a wrong host version.
+ * Correct it here.
+ */
+ return SDHCI_SPEC_300;
+ }
}

return readw(host->ioaddr + reg);
--
1.8.1.2

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