[Patch v9 3/3] phy: Add Qualcomm DWC3 HS/SS PHY driver
Kishon Vijay Abraham I
kishon at ti.com
Sun Sep 14 23:37:12 PDT 2014
Hi,
On Sunday 14 September 2014 07:54 AM, Felipe Balbi wrote:
> Hi,
>
> On Sat, Sep 13, 2014 at 12:16:01PM +0530, Kishon Vijay Abraham I wrote:
>> On Saturday 13 September 2014 12:58 AM, Andy Gross wrote:
>>> This patch adds a new driver for the Qualcomm USB 3.0 PHY that exists on some
>>> Qualcomm platforms. This driver uses the generic PHY framework and will
>>> interact with the DWC3 controller.
>>
>> Do you have dt documentation for this driver?
>
> see patch 1
hmm.. missed that.
>
>>> +static inline void qcom_dwc3_phy_write_readback(
>>> + struct qcom_dwc3_usb_phy *phy_dwc3, u32 offset,
>>> + const u32 mask, u32 val)
>>> +{
>>> + u32 write_val, tmp = readl(phy_dwc3->base + offset);
>>> +
>>> + tmp &= ~mask; /* retain other bits */
>>> + write_val = tmp | val;
>>> +
>>> + writel(write_val, phy_dwc3->base + offset);
>>> +
>>> + /* Read back to see if val was written */
>>
>> Does it fail sometime? I'm not sure if this should be present in the
>> driver since this looks more of a debug code.
>
> this was mentioned before. Silicon bug.
okay.
>
>>> + writel_relaxed(data | SSUSB_CTRL_SS_PHY_RESET,
>>> + phy_dwc3->base + SSUSB_PHY_CTRL_REG);
>>> + usleep_range(2000, 2200);
>>
>> use msleep here..
>
> why ? usleep_range() gives the scheduler oportunity to group timers.
Was of the opinion that for larger delays msleep should be used. But looks like
it is only for 10+ ms (Documentation/timers/timers-howto.txt).
Thanks
Kishon
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