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 <rog...@ti.com>
using the reset-gpios property
Acked-by: Philipp Zabel <p.za...@pengutronix.de>
> ---
> .../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.
> };
>
> 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.
> + 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;
regards
Philipp
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