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[PATCH v3] mmc: sdhci-of-arasan: fix set_clock when a phy is supported

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commit 61b914eb81f8 ("mmc: sdhci-of-arasan: add phy support for
sdhci-of-arasan") introduce phy support for arasan. According to
the vendor's databook, we should make sure the phy is in poweroff
status before we configure the clk stuff. Otherwise it may cause
some IO sample timing issues from the test. And we don't need this
extra operation while running in low performance mode since phy
doesn't trigger sampling block.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>

---

Changes in v3:
- avoid use sleep function with the scope of spinlock because
phy APIs call mutex.

Changes in v2:
- Rename commit msg title to indicate it's a fix

 drivers/mmc/host/sdhci-of-arasan.c | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 2e482b1..b6f4c1d 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -55,8 +55,32 @@ static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
 	return freq;
 }
 
+static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+	bool ctrl_phy = false;
+
+	if (clock > MMC_HIGH_52_MAX_DTR && (!IS_ERR(sdhci_arasan->phy)))
+		ctrl_phy = true;
+
+	if (ctrl_phy) {
+		spin_unlock_irq(&host->lock);
+		phy_power_off(sdhci_arasan->phy);
+		spin_lock_irq(&host->lock);
+	}
+
+	sdhci_set_clock(host, clock);
+
+	if (ctrl_phy) {
+		spin_unlock_irq(&host->lock);
+		phy_power_on(sdhci_arasan->phy);
+		spin_lock_irq(&host->lock);
+	}
+}
+
 static struct sdhci_ops sdhci_arasan_ops = {
-	.set_clock = sdhci_set_clock,
+	.set_clock = sdhci_arasan_set_clock,
 	.get_max_clock = sdhci_pltfm_clk_get_max_clock,
 	.get_timeout_clock = sdhci_arasan_get_timeout_clock,
 	.set_bus_width = sdhci_set_bus_width,
-- 
2.3.7

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[PATCH v3] mmc: sdhci-of-arasan: fix set_clock when a phy is supported Shawn Lin <shawn.lin@rock-chips.com> - 2016-05-04 03:50 +0200
  Re: [PATCH v3] mmc: sdhci-of-arasan: fix set_clock when a phy is  supported Adrian Hunter <adrian.hunter@intel.com> - 2016-05-04 12:00 +0200
  Re: [PATCH v3] mmc: sdhci-of-arasan: fix set_clock when a phy is supported Ulf Hansson <ulf.hansson@linaro.org> - 2016-05-04 13:20 +0200

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