Re: [PATCH 01/13] usb: phy: nop: Add device tree support and binding information

[Roger Quadros <rogerq@ti.com>]

On 02/05/2013 09:26 AM, Felipe Balbi wrote:
> Hi,
> 
> On Mon, Feb 04, 2013 at 05:58:48PM +0200, Roger Quadros wrote:
>> The PHY clock, clock rate, VCC regulator and RESET regulator
>> can now be provided via device tree.
>>
>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>> ---
>>  .../devicetree/bindings/usb/usb-nop-xceiv.txt      |   34 ++++++++++++++++++++
>>  drivers/usb/otg/nop-usb-xceiv.c                    |   31 ++++++++++++++++++
>>  2 files changed, 65 insertions(+), 0 deletions(-)
>>  create mode 100644 Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>>
>> diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> new file mode 100644
>> index 0000000..d7e2726
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> @@ -0,0 +1,34 @@
>> +USB NOP PHY
>> +
>> +Required properties:
>> +- compatible: should be usb-nop-xceiv
>> +
>> +Optional properties:
>> +- clocks: phandle to the PHY clock. Use as per Documentation/devicetree
>> +  /bindings/clock/clock-bindings.txt
>> +  This property is required if clock-frequency is specified.
>> +
>> +- clock-names: Should be "main_clk"
>> +
>> +- clock-frequency: the clock frequency (in Hz) that the PHY clock must
>> +  be configured to.
>> +
>> +- vcc-supply: phandle to the regulator that provides RESET to the PHY.
>> +
>> +- reset-supply: phandle to the regulator that provides power to the PHY.
>> +
>> +Example:
>> +
>> +	hsusb1_phy {
>> +		compatible = "usb-nop-xceiv";
>> +		clock-frequency = <19200000>;
>> +		clocks = <&osc 0>;
>> +		clock-names = "main_clk";
>> +		vcc-supply = <&hsusb1_vcc_regulator>;
>> +		reset-supply = <&hsusb1_reset_regulator>;
>> +	};
>> +
>> +hsusb1_phy is a NOP USB PHY device that gets its clock from an oscillator
>> +and expects that clock to be configured to 19.2MHz by the NOP PHY driver.
>> +hsusb1_vcc_regulator provides power to the PHY and hsusb1_reset_regulator
>> +controls RESET.
>> diff --git a/drivers/usb/otg/nop-usb-xceiv.c b/drivers/usb/otg/nop-usb-xceiv.c
>> index ac027a1..adbb7ab 100644
>> --- a/drivers/usb/otg/nop-usb-xceiv.c
>> +++ b/drivers/usb/otg/nop-usb-xceiv.c
>> @@ -34,6 +34,7 @@
>>  #include <linux/slab.h>
>>  #include <linux/clk.h>
>>  #include <linux/regulator/consumer.h>
>> +#include <linux/of.h>
>>  
>>  struct nop_usb_xceiv {
>>  	struct usb_phy		phy;
>> @@ -138,8 +139,19 @@ static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
>>  	return 0;
>>  }
>>  
>> +static void nop_xeiv_get_dt_pdata(struct device *dev,
> 
> asking to remove, but xeiv != xceiv :-)
> 
>> +				struct nop_usb_xceiv_platform_data *pdata)
>> +{
>> +	struct device_node *node = dev->of_node;
>> +	u32 clk_rate;
>> +
>> +	if (!of_property_read_u32(node, "clock-frequency", &clk_rate))
>> +		pdata->clk_rate = clk_rate;
>> +}
>> +
>>  static int nop_usb_xceiv_probe(struct platform_device *pdev)
>>  {
>> +	struct device *dev = &pdev->dev;
>>  	struct nop_usb_xceiv_platform_data *pdata = pdev->dev.platform_data;
>>  	struct nop_usb_xceiv	*nop;
>>  	enum usb_phy_type	type = USB_PHY_TYPE_USB2;
>> @@ -153,6 +165,17 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>>  	if (!nop->phy.otg)
>>  		return -ENOMEM;
>>  
>> +	if (dev->of_node) {
>> +		pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
>> +		if (!pdata) {
>> +			dev_err(dev, "Memory allocation failure\n");
>> +			return -ENOMEM;
>> +		}
>> +		nop_xeiv_get_dt_pdata(dev, pdata);
> 
> actually, I would prefer to not create pdata at all. I mean, ideally
> pdata would be used to initialize fields in your own structure, so first
> move clk_rate to your own private structure, copy pdata's clk_rate value
> to that, then you don't need this hackery when using DT.
> 
OK, got it. Will revise.

cheers,
-roger