[PATCH v3 2/2] phy: rockchip-inno-usb2: correct 480MHz output clock stable time

Hi Doug,

? 2016?11?15? 02:17, Doug Anderson ??:

William,

On Mon, Nov 14, 2016 at 1:27 AM, William Wu [off-list ref] wrote:

quoted

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 <redacted>
---
Changes in v3:
- fix kbuild test error: too few arguments to function 'usleep_range'

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..0e52b25 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, 1300);

Sight nit that you could also fix the spelling from "waitting" to "waiting".

...but that's pre-existing, so:

Reviewed-by: Douglas Anderson <dianders@chromium.org>

Thanks! I'll add  Reviewed-by and fix the spelling issue.