Re: [PATCH v1 05/11] drivers: usb: twl6030: Add dt support for twl6030 usb

[Rajendra Nayak <rnayak@ti.com>]

On Tuesday 10 July 2012 11:58 AM, ABRAHAM, KISHON VIJAY wrote:
> Hi,
>
> On Tue, Jul 10, 2012 at 11:28 AM, Rajendra Nayak<rnayak@ti.com>  wrote:
>> On Thursday 28 June 2012 05:21 PM, Kishon Vijay Abraham I wrote:
>>>
>>> Add device tree support for twl6030 usb driver.
>>> Update the Documentation with device tree binding information.
>>>
>>> Signed-off-by: Kishon Vijay Abraham I<kishon@ti.com>
>>> ---
>>>    .../devicetree/bindings/usb/twlxxxx-usb.txt        |   18 ++++++++
>>>    drivers/usb/otg/twl6030-usb.c                      |   45
>>> ++++++++++++++------
>>>    2 files changed, 50 insertions(+), 13 deletions(-)
>>>    create mode 100644 Documentation/devicetree/bindings/usb/twlxxxx-usb.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/usb/twlxxxx-usb.txt
>>> b/Documentation/devicetree/bindings/usb/twlxxxx-usb.txt
>>> new file mode 100644
>>> index 0000000..f293271
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/usb/twlxxxx-usb.txt
>>> @@ -0,0 +1,18 @@
>>> +USB COMPARATOR OF TWL CHIPS
>>> +
>>> +TWL6030 USB COMPARATOR
>>> + - compatible : Should be "ti,twl6030-usb"
>>> + - interrupts : Two interrupt numbers to the cpu should be specified.
>>> First
>>> +   interrupt number is the otg interrupt number that raises ID interrupts
>>> when
>>> +   the controller has to act as host and the second interrupt number is
>>> the
>>> +   usb interrupt number that raises VBUS interrupts when the controller
>>> has to
>>> +   act as device
>>> + - regulator :<supply-name>   can be "vusb" or "ldousb"
>>> + -<supply-name>-supply : phandle to the regulator device tree node
>>> +
>>> +twl6030-usb {
>>> +       compatible = "ti,twl6030-usb";
>>> +       interrupts =<   4 10>;
>>> +       regulator = "vusb";
>>> +       vusb-supply =<&vusb>;
>>
>>
>> This doesn't seem right. Why do you ned a 'regulator' string along
>> with the phandle?
>
> The original code was something like
> 	if (twl->features&  TWL6025_SUBCLASS)
> 		regulator_name = "ldousb";
> 	else
> 		regulator_name = "vusb";
>
> I wasn't sure how to handle this *TWL6025_SUBCLASS* stuff.
>
>>
>>> +};
>>> diff --git a/drivers/usb/otg/twl6030-usb.c b/drivers/usb/otg/twl6030-usb.c
>>> index 6a361d2..20b7abe 100644
>>> --- a/drivers/usb/otg/twl6030-usb.c
>>> +++ b/drivers/usb/otg/twl6030-usb.c
>>> @@ -105,7 +105,7 @@ struct twl6030_usb {
>>>          u8                      asleep;
>>>          bool                    irq_enabled;
>>>          bool                    vbus_enable;
>>> -       unsigned long           features;
>>> +       const char              *regulator;
>>>    };
>>>
>>>    #define       comparator_to_twl(x) container_of((x), struct twl6030_usb,
>>> comparator)
>>> @@ -153,13 +153,6 @@ static int twl6030_start_srp(struct phy_companion
>>> *comparator)
>>>
>>>    static int twl6030_usb_ldo_init(struct twl6030_usb *twl)
>>>    {
>>> -       char *regulator_name;
>>> -
>>> -       if (twl->features&   TWL6025_SUBCLASS)
>>>
>>> -               regulator_name = "ldousb";
>>> -       else
>>> -               regulator_name = "vusb";
>>> -
>>>          /* Set to OTG_REV 1.3 and turn on the ID_WAKEUP_COMP */
>>>          twl6030_writeb(twl, TWL6030_MODULE_ID0 , 0x1, TWL6030_BACKUP_REG);
>>>
>>> @@ -169,7 +162,7 @@ static int twl6030_usb_ldo_init(struct twl6030_usb
>>> *twl)
>>>          /* Program MISC2 register and set bit VUSB_IN_VBAT */
>>>          twl6030_writeb(twl, TWL6030_MODULE_ID0 , 0x10, TWL6030_MISC2);
>>>
>>> -       twl->usb3v3 = regulator_get(twl->dev, regulator_name);
>>> +       twl->usb3v3 = regulator_get(twl->dev, twl->regulator);
>>>          if (IS_ERR(twl->usb3v3))
>>>                  return -ENODEV;
>>>
>>> @@ -324,9 +317,9 @@ static int __devinit twl6030_usb_probe(struct
>>> platform_device *pdev)
>>>    {
>>>          struct twl6030_usb      *twl;
>>>          int                     status, err;
>>> -       struct twl4030_usb_data *pdata;
>>> -       struct device *dev =&pdev->dev;
>>>
>>> -       pdata = dev->platform_data;
>>> +       struct device_node      *np = pdev->dev.of_node;
>>> +       struct device           *dev =&pdev->dev;
>>>
>>> +       struct twl4030_usb_data *pdata = dev->platform_data;
>>>
>>>          twl = devm_kzalloc(dev, sizeof *twl, GFP_KERNEL);
>>>          if (!twl)
>>> @@ -335,13 +328,28 @@ static int __devinit twl6030_usb_probe(struct
>>> platform_device *pdev)
>>>          twl->dev                =&pdev->dev;
>>>
>>>          twl->irq1               = platform_get_irq(pdev, 0);
>>>          twl->irq2               = platform_get_irq(pdev, 1);
>>> -       twl->features           = pdata->features;
>>>          twl->linkstat           = OMAP_MUSB_UNKNOWN;
>>>
>>>          twl->comparator.set_vbus        = twl6030_set_vbus;
>>>          twl->comparator.start_srp       = twl6030_start_srp;
>>>          omap_usb2_set_comparator(&twl->comparator);
>>>
>>> +       if (np) {
>>> +               err = of_property_read_string(np,
>>> "regulator",&twl->regulator);
>>>
>>> +               if (err<   0) {
>>> +                       dev_err(&pdev->dev, "unable to get regulator\n");
>>> +                       return err;
>>> +               }
>>
>>
>> Isn't there a better way for the driver to know which supply to use instead
>> of DT passing the supply name?
>
> The problem I see is this same driver is used for twl6030 and twl6025
> and the regulator used is different for these two chips (And I think

hmm, so based on what chip is used on a board, shouldn't the board dts
file just map the right regulator with a supply name?
This doesn't look like something the driver should be bothered about.

> twl6025 will also use the same dt file as twl6030 as I don't see a
> different file for 6025).
>
> Thanks
> Kishon