On 08/14/2013 06:27 PM, Philipp Zabel wrote:
> Hi Roger,
>
> Am Mittwoch, den 14.08.2013, 16:58 +0300 schrieb Roger Quadros:
>> Modelling the RESET line as a regulator supply wasn't a good idea
>> as it kind of abuses the regulator framework and also makes adaptation
>> code more complex.
>>
>> Instead, manage the RESET gpio line directly in the driver. Update
>> the device tree binding information.
>>
>> This also makes us easy to migrate to a dedicated GPIO RESET controller
>> whenever it becomes available.
>>
>> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>
> using the reset-gpios property
> Acked-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
>
>> ---
>> .../devicetree/bindings/usb/usb-nop-xceiv.txt | 7 +--
>> drivers/usb/phy/phy-nop.c | 48 ++++++++++++--------
>> 2 files changed, 32 insertions(+), 23 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> index d7e2726..5535f3b 100644
>> --- a/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> +++ b/Documentation/devicetree/bindings/usb/usb-nop-xceiv.txt
>> @@ -15,7 +15,7 @@ Optional properties:
>>
>> - vcc-supply: phandle to the regulator that provides RESET to the PHY.
>>
>> -- reset-supply: phandle to the regulator that provides power to the PHY.
>> +- reset-gpios: Should specify the GPIO for reset.
>>
>> Example:
>>
>> @@ -25,10 +25,9 @@ Example:
>> clocks = <&osc 0>;
>> clock-names = "main_clk";
>> vcc-supply = <&hsusb1_vcc_regulator>;
>> - reset-supply = <&hsusb1_reset_regulator>;
>> + reset-gpios = <&gpio1 7>;
>
> Yes, although the example should probably include GPIO_ACTIVE_LOW or
> GPIO_ACTIVE_HIGH flags.
>
OK.
>> };
>>
>> 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.
>> +hsusb1_vcc_regulator provides power to the PHY and GPIO 7 controls RESET.
>> diff --git a/drivers/usb/phy/phy-nop.c b/drivers/usb/phy/phy-nop.c
>> index 55445e5d..af5e1a6 100644
>> --- a/drivers/usb/phy/phy-nop.c
>> +++ b/drivers/usb/phy/phy-nop.c
>> @@ -35,6 +35,9 @@
>> #include <linux/clk.h>
>> #include <linux/regulator/consumer.h>
>> #include <linux/of.h>
>> +#include <linux/of_gpio.h>
>> +#include <linux/gpio.h>
>> +#include <linux/delay.h>
>>
>> struct nop_usb_xceiv {
>> struct usb_phy phy;
>> @@ -42,6 +45,7 @@ struct nop_usb_xceiv {
>> struct clk *clk;
>> struct regulator *vcc;
>> struct regulator *reset;
>> + int gpio_reset;
>> };
>>
>> static struct platform_device *pd;
>> @@ -70,6 +74,15 @@ static int nop_set_suspend(struct usb_phy *x, int suspend)
>> return 0;
>> }
>>
>> +static void nop_gpio_reset(int gpio, int state)
>> +{
>> + if (gpio_is_valid(gpio))
>> + gpio_set_value(gpio, state);
>> +
>> + if (state)
>> + usleep_range(10000, 20000);
>> +}
>> +
>> static int nop_init(struct usb_phy *phy)
>> {
>> struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
>> @@ -82,11 +95,8 @@ static int nop_init(struct usb_phy *phy)
>> if (!IS_ERR(nop->clk))
>> clk_enable(nop->clk);
>>
>> - if (!IS_ERR(nop->reset)) {
>> - /* De-assert RESET */
>> - if (regulator_enable(nop->reset))
>> - dev_err(phy->dev, "Failed to de-assert reset\n");
>> - }
>> + /* De-assert RESET */
>> + nop_gpio_reset(nop->gpio_reset, 1);
>>
>> return 0;
>> }
>> @@ -95,11 +105,8 @@ static void nop_shutdown(struct usb_phy *phy)
>> {
>> struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
>>
>> - if (!IS_ERR(nop->reset)) {
>> - /* Assert RESET */
>> - if (regulator_disable(nop->reset))
>> - dev_err(phy->dev, "Failed to assert reset\n");
>> - }
>> + /* Assert RESET */
>> + nop_gpio_reset(nop->gpio_reset, 0);
>>
>> if (!IS_ERR(nop->clk))
>> clk_disable(nop->clk);
>> @@ -148,7 +155,6 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>> int err;
>> u32 clk_rate = 0;
>> bool needs_vcc = false;
>> - bool needs_reset = false;
>>
>> nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL);
>> if (!nop)
>> @@ -166,13 +172,15 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>> clk_rate = 0;
>>
>> needs_vcc = of_property_read_bool(node, "vcc-supply");
>> - needs_reset = of_property_read_bool(node, "reset-supply");
>> + nop->gpio_reset = of_get_named_gpio(node, "reset-gpios", 0);
>
> I'd suggest to use of_get_named_gpio_flags to also obtain the polarity
> from the flags.
OK. good point.
>
>> + if (nop->gpio_reset == -EPROBE_DEFER)
>> + return -EPROBE_DEFER;
>>
>> } else if (pdata) {
>> type = pdata->type;
>> clk_rate = pdata->clk_rate;
>> needs_vcc = pdata->needs_vcc;
>> - needs_reset = pdata->needs_reset;
>> + nop->gpio_reset = pdata->gpio_reset;
>> }
>>
>> nop->clk = devm_clk_get(&pdev->dev, "main_clk");
>> @@ -205,12 +213,14 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
>> return -EPROBE_DEFER;
>> }
>>
>> - nop->reset = devm_regulator_get(&pdev->dev, "reset");
>> - if (IS_ERR(nop->reset)) {
>> - dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n",
>> - PTR_ERR(nop->reset));
>> - if (needs_reset)
>> - return -EPROBE_DEFER;
>> + if (gpio_is_valid(nop->gpio_reset)) {
>> + err = devm_gpio_request_one(dev, nop->gpio_reset,
>> + GPIOF_OUT_INIT_HIGH, dev_name(dev));
>> + if (err) {
>> + dev_err(dev, "Error requesting RESET GPIO %d\n",
>> + nop->gpio_reset);
>> + return err;
>> + }
>> }
>>
>> nop->dev = &pdev->dev;
>
Thanks for the review. I'll send a v2.
cheers,
-roger
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