Re: [PATCH v4 2/2] usb: dwc3: adapt dwc3 core to use Generic PHY Framework

From: Vivek Gautam
Date: Wed Jan 22 2014 - 01:04:58 EST


Hi,


On Tue, Jan 21, 2014 at 7:30 PM, Roger Quadros <rogerq@xxxxxx> wrote:
> Hi Kishon,
>
> On 01/21/2014 12:11 PM, Kishon Vijay Abraham I wrote:
>> Adapted dwc3 core to use the Generic PHY Framework. So for init, exit,
>> power_on and power_off the following APIs are used phy_init(), phy_exit(),
>> phy_power_on() and phy_power_off().
>>
>> However using the old USB phy library wont be removed till the PHYs of all
>> other SoC's using dwc3 core is adapted to the Generic PHY Framework.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
>> ---
>> Changes from v3:
>> * avoided using quirks
>>
>> Documentation/devicetree/bindings/usb/dwc3.txt | 6 ++-
>> drivers/usb/dwc3/core.c | 60 ++++++++++++++++++++++++
>> drivers/usb/dwc3/core.h | 7 +++
>> 3 files changed, 71 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
>> index e807635..471366d 100644
>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>> @@ -6,11 +6,13 @@ Required properties:
>> - compatible: must be "snps,dwc3"
>> - reg : Address and length of the register set for the device
>> - interrupts: Interrupts used by the dwc3 controller.
>> +
>> +Optional properties:
>> - usb-phy : array of phandle for the PHY device. The first element
>> in the array is expected to be a handle to the USB2/HS PHY and
>> the second element is expected to be a handle to the USB3/SS PHY
>> -
>> -Optional properties:
>> + - phys: from the *Generic PHY* bindings
>> + - phy-names: from the *Generic PHY* bindings
>> - tx-fifo-resize: determines if the FIFO *has* to be reallocated.
>>
>> This is usually a subnode to DWC3 glue to which it is connected.
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index e009d4e..036d589 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -82,6 +82,11 @@ static void dwc3_core_soft_reset(struct dwc3 *dwc)
>>
>> usb_phy_init(dwc->usb2_phy);
>> usb_phy_init(dwc->usb3_phy);
>> + if (dwc->usb2_generic_phy)
>> + phy_init(dwc->usb2_generic_phy);
>
> What if phy_init() fails? You need to report and fail. Same applies for all PHY apis in this patch.
>
>> + if (dwc->usb3_generic_phy)
>> + phy_init(dwc->usb3_generic_phy);
>> +
>> mdelay(100);
>>
>> /* Clear USB3 PHY reset */
>> @@ -343,6 +348,11 @@ static void dwc3_core_exit(struct dwc3 *dwc)
>> {
>> usb_phy_shutdown(dwc->usb2_phy);
>> usb_phy_shutdown(dwc->usb3_phy);
>> + if (dwc->usb2_generic_phy)
>> + phy_exit(dwc->usb2_generic_phy);
>> + if (dwc->usb3_generic_phy)
>> + phy_exit(dwc->usb3_generic_phy);
>> +
>> }
>>
>> #define DWC3_ALIGN_MASK (16 - 1)
>> @@ -433,6 +443,32 @@ static int dwc3_probe(struct platform_device *pdev)
>> }
>> }
>>
>> + dwc->usb2_generic_phy = devm_phy_get(dev, "usb2-phy");
>> + if (IS_ERR(dwc->usb2_generic_phy)) {
>> + ret = PTR_ERR(dwc->usb2_generic_phy);
>> + if (ret == -ENOSYS || ret == -ENODEV) {
>> + dwc->usb2_generic_phy = NULL;
>> + } else if (ret == -EPROBE_DEFER) {
>> + return ret;
>> + } else {
>> + dev_err(dev, "no usb2 phy configured\n");
>> + return ret;
>> + }
>> + }
>> +
>> + dwc->usb3_generic_phy = devm_phy_get(dev, "usb3-phy");
>> + if (IS_ERR(dwc->usb3_generic_phy)) {
>> + ret = PTR_ERR(dwc->usb3_generic_phy);
>> + if (ret == -ENOSYS || ret == -ENODEV) {
>> + dwc->usb3_generic_phy = NULL;
>> + } else if (ret == -EPROBE_DEFER) {
>> + return ret;
>> + } else {
>> + dev_err(dev, "no usb3 phy configured\n");
>> + return ret;
>> + }
>> + }
>> +
>> dwc->xhci_resources[0].start = res->start;
>> dwc->xhci_resources[0].end = dwc->xhci_resources[0].start +
>> DWC3_XHCI_REGS_END;
>> @@ -482,6 +518,11 @@ static int dwc3_probe(struct platform_device *pdev)
>> usb_phy_set_suspend(dwc->usb2_phy, 0);
>> usb_phy_set_suspend(dwc->usb3_phy, 0);
>>
>> + if (dwc->usb2_generic_phy)
>> + phy_power_on(dwc->usb2_generic_phy);
>> + if (dwc->usb3_generic_phy)
>> + phy_power_on(dwc->usb3_generic_phy);
>> +
>
> Is it OK to power on the phy before phy_init()?

Isn't phy_init() being done before phy_power_on() in the
core_soft_reset() in this patch ?
Isn't that what you want here ?

>
> I suggest to move phy_init() from core_soft_reset() to here, just before phy_power_on().

core_soft_reset() is called before phy_power_on() itself from
dwc3_core_init(), right ?
will moving the phy_inti() here make nay difference ?

>
>> ret = dwc3_event_buffers_setup(dwc);
>> if (ret) {
>> dev_err(dwc->dev, "failed to setup event buffers\n");
[...]
snip


--
Best Regards
Vivek Gautam
Samsung R&D Institute, Bangalore
India
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