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[PATCH v2 0/2] phy: rockchip-inno-usb2: correct 480MHz clk_ops callbacks and stable time

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  [PATCH v2 0/2] phy: rockchip-inno-usb2: correct 480MHz clk_ops callbacks and stable time William Wu <wulf@rock-chips.com> - 2016-11-14 08:10 +0100
    [PATCH v2 2/2] phy: rockchip-inno-usb2: correct 480MHz output clock stable time William Wu <wulf@rock-chips.com> - 2016-11-14 08:10 +0100

#1521361 — [PATCH v2 0/2] phy: rockchip-inno-usb2: correct 480MHz clk_ops callbacks and stable time

This series try to correct the 480MHz output clock of USB2 PHY
clk_ops callback and fix the delay time. It aims to make the
480MHz clock more sensible and stable.

Tested on rk3366/rk3399 EVB board.

William Wu (2):
  phy: rockchip-inno-usb2: correct clk_ops callback
  phy: rockchip-inno-usb2: correct 480MHz output clock stable time

 drivers/phy/phy-rockchip-inno-usb2.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

-- 
2.0.0

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#1521363 — [PATCH v2 2/2] phy: rockchip-inno-usb2: correct 480MHz output clock stable time

We found that the system crashed due to 480MHz output clock of
USB2 PHY was unstable after clock had been enabled by gpu module.

Theoretically, 1 millisecond is a critical value for 480MHz
output clock stable time, so we try to change the delay time
to 1.2 millisecond to avoid this issue.

And the commit ed907fb1d7c3 ("phy: rockchip-inno-usb2: correct
clk_ops callback") used prepare callbacks instead of enable
callbacks to support gate a clk if the operation may sleep. So
we can switch from delay to sleep functions.

Signed-off-by: William Wu <wulf@rock-chips.com>
---
Changes in v2:
- use usleep_range() function instead of mdelay()

 drivers/phy/phy-rockchip-inno-usb2.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/phy/phy-rockchip-inno-usb2.c b/drivers/phy/phy-rockchip-inno-usb2.c
index 365e077..578290b 100644
--- a/drivers/phy/phy-rockchip-inno-usb2.c
+++ b/drivers/phy/phy-rockchip-inno-usb2.c
@@ -166,7 +166,7 @@ static int rockchip_usb2phy_clk480m_prepare(struct clk_hw *hw)
 			return ret;
 
 		/* waitting for the clk become stable */
-		mdelay(1);
+		usleep_range(1200);
 	}
 
 	return 0;
-- 
2.0.0

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