From mboxrd@z Thu Jan 1 00:00:00 1970 From: wlf Subject: Re: [PATCH v3 2/2] phy: rockchip-inno-usb2: correct 480MHz output clock stable time Date: Tue, 15 Nov 2016 11:23:26 +0800 Message-ID: <4919785a-2460-145d-e2e4-944ae7940633@rock-chips.com> References: <1479115631-20137-1-git-send-email-wulf@rock-chips.com> <1479115631-20137-3-git-send-email-wulf@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Doug Anderson Cc: Kishon Vijay Abraham I , =?UTF-8?Q?Heiko_St=c3=bcbner?= , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "open list:ARM/Rockchip SoC..." , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Rob Herring , Frank Wang , =?UTF-8?B?6buE5rab?= , Brian Norris , Guenter Roeck List-Id: devicetree@vger.kernel.org Hi Doug, 在 2016年11月15日 02:17, Doug Anderson 写道: > William, > > On Mon, Nov 14, 2016 at 1:27 AM, William Wu wrote: >> 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 >> --- >> 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 Thanks! I'll add Reviewed-by and fix the spelling issue. > > > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html