* Re: [PATCH v2 2/9] usb: phy: nop: Don't use regulator framework for RESET line
[not found] ` <1376561909-4406-3-git-send-email-rogerq@ti.com>
@ 2013-09-23 18:05 ` Roger Quadros
0 siblings, 0 replies; 4+ messages in thread
From: Roger Quadros @ 2013-09-23 18:05 UTC (permalink / raw)
To: balbi
Cc: devicetree, bcousson, tony, linux-usb, broonie, p.zabel,
linux-omap, linux-arm-kernel, Roger Quadros
Hi Felipe,
There is an issue with this patch and is shown below.
I will send a v3 for this.
On 08/15/2013 01:18 PM, Roger Quadros wrote:
> 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@ti.com>
> ---
> .../devicetree/bindings/usb/usb-nop-xceiv.txt | 7 +-
> drivers/usb/phy/phy-nop.c | 71 ++++++++++++++-----
> 2 files changed, 55 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..1bd37fa 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 GPIO_ACTIVE_LOW>;
> };
>
> 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..1f88c32 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 +45,8 @@ struct nop_usb_xceiv {
> struct clk *clk;
> struct regulator *vcc;
> struct regulator *reset;
> + int gpio_reset;
> + bool reset_active_low;
> };
>
> static struct platform_device *pd;
> @@ -70,6 +75,23 @@ static int nop_set_suspend(struct usb_phy *x, int suspend)
> return 0;
> }
>
> +static void nop_reset_set(struct nop_usb_xceiv *nop, int asserted)
> +{
> + int value;
> +
> + if (!gpio_is_valid(nop->gpio_reset))
> + return;
> +
> + value = asserted;
> + if (nop->reset_active_low)
> + value = !value;
> +
> + gpio_set_value_cansleep(nop->gpio_reset, value);
> +
> + if (!asserted)
> + usleep_range(10000, 20000);
> +}
> +
> static int nop_init(struct usb_phy *phy)
> {
> struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
> @@ -82,11 +104,8 @@ 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_reset_set(nop, 0);
>
> return 0;
> }
> @@ -95,11 +114,8 @@ 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_reset_set(nop, 1);
>
> if (!IS_ERR(nop->clk))
> clk_disable(nop->clk);
> @@ -148,7 +164,6 @@ 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)
> @@ -159,20 +174,28 @@ static int nop_usb_xceiv_probe(struct platform_device *pdev)
> if (!nop->phy.otg)
> return -ENOMEM;
>
> + nop->reset_active_low = true; /* default behaviour */
> +
> if (dev->of_node) {
> struct device_node *node = dev->of_node;
> + enum of_gpio_flags flags;
>
> if (of_property_read_u32(node, "clock-frequency", &clk_rate))
> 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_flags(node, "reset-gpios",
> + 0, &flags);
> + if (nop->gpio_reset == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> +
> + nop->reset_active_low = flags & OF_GPIO_ACTIVE_LOW;
>
> } 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 +228,22 @@ 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)) {
> + unsigned long gpio_flags;
> +
> + /* Assert RESET */
> + if (nop->reset_active_low)
> + gpio_flags = GPIOF_OUT_INIT_HIGH;
> + else
> + gpio_flags = GPIOF_OUT_INIT_LOW;
The operations inside if/else need to be reversed.
> +
> + err = devm_gpio_request_one(dev, nop->gpio_reset,
> + gpio_flags, dev_name(dev));
> + if (err) {
> + dev_err(dev, "Error requesting RESET GPIO %d\n",
> + nop->gpio_reset);
> + return err;
> + }
> }
>
> nop->dev = &pdev->dev;
>
cheers,
-roger
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