[PATCH v2] mmc: sdhci-of-arasan: fix set_clock when a phy is supported

From: Shawn Lin
Date: Thu Apr 28 2016 - 04:40:00 EST


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@xxxxxxxxxxxxxx>

---

Changes in v2:
- change commit msg title to indicate it's a fix
- fix a typo in commmit msg

drivers/mmc/host/sdhci-of-arasan.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 2e482b1..20b859e 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -55,8 +55,26 @@ 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)
+ phy_power_off(sdhci_arasan->phy);
+
+ sdhci_set_clock(host, clock);
+
+ if (ctrl_phy)
+ phy_power_on(sdhci_arasan->phy);
+}
+
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