Re: [PATCH] usb: chipidea: imx: Do not access CLKONOFF on i.MX51

[Andrey Smirnov]

On Mon, May 8, 2017 at 5:47 PM, Peter Chen <hzpeterchen@xxxxxxxxx> wrote:
> On Mon, May 08, 2017 at 07:15:01AM -0700, Andrey Smirnov wrote:
>> Unlike i.MX53, i.MX51's USBOH3 register file does not implemenent
>> registers past offset 0x018, which includes
>> MX53_USB_CLKONOFF_CTRL_OFFSET and trying to access that register on
>> said platform results in external abort.
>>
>> Fix it by enabling CLKONOFF accessing codepath only for i.MX53.
>>
>> Fixes 3be3251db0887f721f9c110e1966900922fc4ff4
>> ("usb: chipidea: imx: Disable internal 60Mhz clock with ULPI PHY")
>>
>> Cc: cphealy@xxxxxxxxx
>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>> Cc: linux-usb@xxxxxxxxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
>> ---
>>  drivers/usb/chipidea/usbmisc_imx.c | 44 +++++++++++++++++++++++++++++---------
>>  1 file changed, 34 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
>> index e77a4ed..fc21f92 100644
>> --- a/drivers/usb/chipidea/usbmisc_imx.c
>> +++ b/drivers/usb/chipidea/usbmisc_imx.c
>> @@ -195,7 +195,7 @@ static int usbmisc_imx27_init(struct imx_usbmisc_data *data)
>>       return 0;
>>  }
>>
>> -static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
>> +static int usbmisc_imx5x_init(struct imx_usbmisc_data *data, bool has_clkonoff)
>>  {
>>       struct imx_usbmisc *usbmisc = dev_get_drvdata(data->dev);
>>       void __iomem *reg = NULL;
>> @@ -242,10 +242,15 @@ static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
>>                       val = readl(reg) | MX53_USB_UHx_CTRL_WAKE_UP_EN
>>                               | MX53_USB_UHx_CTRL_ULPI_INT_EN;
>>                       writel(val, reg);
>> -                     /* Disable internal 60Mhz clock */
>> -                     reg = usbmisc->base + MX53_USB_CLKONOFF_CTRL_OFFSET;
>> -                     val = readl(reg) | MX53_USB_CLKONOFF_CTRL_H2_INT60CKOFF;
>> -                     writel(val, reg);
>> +                     if (has_clkonoff) {
>> +                             /* Disable internal 60Mhz clock */
>> +                             reg = usbmisc->base +
>> +                                     MX53_USB_CLKONOFF_CTRL_OFFSET;
>> +                             val = readl(reg) |
>> +                                     MX53_USB_CLKONOFF_CTRL_H2_INT60CKOFF;
>> +                             writel(val, reg);
>> +                     }
>> +
>>               }
>>               if (data->disable_oc) {
>>                       reg = usbmisc->base + MX53_USB_UH2_CTRL_OFFSET;
>> @@ -267,10 +272,15 @@ static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
>>                       val = readl(reg) | MX53_USB_UHx_CTRL_WAKE_UP_EN
>>                               | MX53_USB_UHx_CTRL_ULPI_INT_EN;
>>                       writel(val, reg);
>> -                     /* Disable internal 60Mhz clock */
>> -                     reg = usbmisc->base + MX53_USB_CLKONOFF_CTRL_OFFSET;
>> -                     val = readl(reg) | MX53_USB_CLKONOFF_CTRL_H3_INT60CKOFF;
>> -                     writel(val, reg);
>> +
>> +                     if (has_clkonoff) {
>> +                             /* Disable internal 60Mhz clock */
>> +                             reg = usbmisc->base +
>> +                                     MX53_USB_CLKONOFF_CTRL_OFFSET;
>> +                             val = readl(reg) |
>> +                                     MX53_USB_CLKONOFF_CTRL_H3_INT60CKOFF;
>> +                             writel(val, reg);
>> +                     }
>>               }
>>               if (data->disable_oc) {
>>                       reg = usbmisc->base + MX53_USB_UH3_CTRL_OFFSET;
>> @@ -285,6 +295,16 @@ static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
>>       return 0;
>>  }
>>
>> +static int usbmisc_imx51_init(struct imx_usbmisc_data *data)
>> +{
>> +     return usbmisc_imx5x_init(data, false);
>> +}
>> +
>> +static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
>> +{
>> +     return usbmisc_imx5x_init(data, true);
>> +}
>> +
>>  static int usbmisc_imx6q_set_wakeup
>>       (struct imx_usbmisc_data *data, bool enabled)
>>  {
>> @@ -456,6 +476,10 @@ static const struct usbmisc_ops imx27_usbmisc_ops = {
>>       .init = usbmisc_imx27_init,
>>  };
>>
>> +static const struct usbmisc_ops imx51_usbmisc_ops = {
>> +     .init = usbmisc_imx51_init,
>> +};
>> +
>>  static const struct usbmisc_ops imx53_usbmisc_ops = {
>>       .init = usbmisc_imx53_init,
>>  };
>> @@ -536,7 +560,7 @@ static const struct of_device_id usbmisc_imx_dt_ids[] = {
>>       },
>>       {
>>               .compatible = "fsl,imx51-usbmisc",
>> -             .data = &imx53_usbmisc_ops,
>> +             .data = &imx51_usbmisc_ops,
>>       },
>>       {
>>               .compatible = "fsl,imx53-usbmisc",
>
> Thanks for fixing it.
>
> I prefer using is_imx53_usbmisc stands for if it is imx53 usbmisc
> at usbmisc_imx53_init to fix it, you can prefer to:
> drivers/usb/phy/phy-mxs-usb.c.
>

OK, sounds good, I'll update and resubmit the patch.

Thanks,
Andrey Smirnov