[PATCH v6 5/5] mmc: sdhci-of-arasan: implement enhanced strobe callback

Shawn Lin
2016-05-26T01:56:43Z

Currently sdhci-arasan 5.1 can support enhanced strobe function,
and we now limit it just for "arasan,sdhci-5.1". Add
mmc-hs400-enhanced-strobe in DT to enable the function if we're
sure our controller can support it.

Signed-off-by: Shawn Lin <shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org>

Acked-by: Adrian Hunter <adrian.hunter-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Reviewed-by: Doug Anderson <dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
Tested-by: Doug Anderson <dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
---

Changes in v6:
- add Doug's test-tag

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

drivers/mmc/host/sdhci-of-arasan.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index b6f4c1d..533e2bc 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -25,7 +25,9 @@
#include "sdhci-pltfm.h"

#define SDHCI_ARASAN_CLK_CTRL_OFFSET 0x2c
+#define SDHCI_ARASAN_VENDOR_REGISTER 0x78

+#define VENDOR_ENHANCED_STROBE BIT(0)
#define CLK_CTRL_TIMEOUT_SHIFT 16
#define CLK_CTRL_TIMEOUT_MASK (0xf << CLK_CTRL_TIMEOUT_SHIFT)
#define CLK_CTRL_TIMEOUT_MIN_EXP 13
@@ -79,6 +81,21 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
}
}

+static void sdhci_arasan_hs400_enhanced_strobe(struct mmc_host *mmc,
+ struct mmc_ios *ios)
+{
+ u32 vendor;
+ struct sdhci_host *host = mmc_priv(mmc);
+
+ vendor = readl(host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
+ if (ios->enhanced_strobe)
+ vendor |= VENDOR_ENHANCED_STROBE;
+ else
+ vendor &= ~VENDOR_ENHANCED_STROBE;
+
+ writel(vendor, host->ioaddr + SDHCI_ARASAN_VENDOR_REGISTER);
+}
+
static struct sdhci_ops sdhci_arasan_ops = {
.set_clock = sdhci_arasan_set_clock,
.get_max_clock = sdhci_pltfm_clk_get_max_clock,
@@ -245,6 +262,9 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
dev_err(&pdev->dev, "phy_power_on err.\n");
goto err_phy_power;
}
+
+ host->mmc_host_ops.hs400_enhanced_strobe =
+ sdhci_arasan_hs400_enhanced_strobe;
}

ret = sdhci_add_host(host);
--
2.3.7

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