[PATCH v5 15/15] usb: phy-mxs: Add sync time after controller clear phcd

Sergei Shtylyov sergei.shtylyov at cogentembedded.com
Mon Dec 9 13:20:08 EST 2013


Hello.

On 12/09/2013 09:31 AM, Peter Chen wrote:

> After clear portsc.phcd, PHY needs 200us stable time for switch
> 32K clock to AHB clock.

> Signed-off-by: Peter Chen <peter.chen at freescale.com>
> ---
>   drivers/usb/phy/phy-mxs-usb.c |   11 +++++++++++
>   1 files changed, 11 insertions(+), 0 deletions(-)

> diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
> index e18fdf3..7ae5225 100644
> --- a/drivers/usb/phy/phy-mxs-usb.c
> +++ b/drivers/usb/phy/phy-mxs-usb.c
> @@ -151,6 +151,15 @@ static inline bool is_imx6sl_phy(struct mxs_phy *mxs_phy)
>   	return mxs_phy->data == &imx6sl_phy_data;
>   }
>
> +/*
> + * PHY needs some 32K cycles to switch from 32K clock to
> + * bus (such as AHB/AXI, etc) clock.
> + */
> +static void mxs_phy_clock_switch(void)
> +{
> +	usleep_range(300, 400);
> +}
> +

    Don't think this is a good name for this function since it doesn't really 
switch anything, just waits. I'd suggest something like 
mxs_phy_clock_switch_delay().

WBR, Sergei




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