[PATCH] clk: rockchip: Don't restore invalid cached phase

[Shawn Lin]

We inevitably cache the invalid phase when the clock provider
be reparented from orphan to its real parent in the first place,
thus we may mess up the initialization of MMC cards since we
only set the default sample phase and drive phase later on.
So we should skip to restore the invalid phase. And this patch
also corrects the error path to return invalid pointer to clk if
clk_notifier_register failed introduced by the same offending
commit.

Fixes: 60cf09e45fbc ("clk: rockchip: Restore the clock phase after the rate was changed")
Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
---

 drivers/clk/rockchip/clk-mmc-phase.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/rockchip/clk-mmc-phase.c b/drivers/clk/rockchip/clk-mmc-phase.c
index dc4c227..c8c6119 100644
--- a/drivers/clk/rockchip/clk-mmc-phase.c
+++ b/drivers/clk/rockchip/clk-mmc-phase.c
@@ -181,7 +181,8 @@ static int rockchip_mmc_clk_rate_notify(struct notifier_block *nb,
 	if (event == PRE_RATE_CHANGE)
 		mmc_clock->cached_phase =
 			rockchip_mmc_get_phase(&mmc_clock->hw);
-	else if (event == POST_RATE_CHANGE)
+	else if (mmc_clock->cached_phase != -EINVAL &&
+		 event == POST_RATE_CHANGE)
 		rockchip_mmc_set_phase(&mmc_clock->hw, mmc_clock->cached_phase);
 
 	return NOTIFY_DONE;
@@ -211,8 +212,10 @@ struct clk *rockchip_clk_register_mmc(const char *name,
 	mmc_clock->shift = shift;
 
 	clk = clk_register(NULL, &mmc_clock->hw);
-	if (IS_ERR(clk))
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
 		goto err_register;
+	}
 
 	mmc_clock->clk_rate_change_nb.notifier_call =
 				&rockchip_mmc_clk_rate_notify;
@@ -225,5 +228,5 @@ struct clk *rockchip_clk_register_mmc(const char *name,
 	clk_unregister(clk);
 err_register:
 	kfree(mmc_clock);
-	return clk;
+	return ERR_PTR(ret);
 }
-- 
1.9.1