diff options
| author | Oleksandr Suvorov <oleksandr.suvorov@toradex.com> | 2019-11-11 14:47:08 +0100 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2020-02-12 11:06:07 +0100 |
| commit | 4009291ebb6f79e0ee451539e28d87f5d041ae4b (patch) | |
| tree | 07ec8b180f79cb40b85650bdcd59de9d2be8fd72 /drivers/usb | |
| parent | 9f8104b2b55285be20391db8ab61e8ed966062f7 (diff) | |
usb: phy: phy-generic: add an ability to reset on resume
Regular USB device gets power down in system suspend.
New hardware designs require to include USB devices as part of main
scheme. If this case the power could be provide to a device
unmanagable. The best option to reset this kind of devices is to
reset it on USB physical interface level.
Add this ability. Using "reset-on-resume" DT-option for usb-generic driver
enables reset nested device on resume event by gpio interface.
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
Diffstat (limited to 'drivers/usb')
| -rw-r--r-- | drivers/usb/phy/phy-generic.c | 44 | ||||
| -rw-r--r-- | drivers/usb/phy/phy-generic.h | 1 |
2 files changed, 29 insertions, 16 deletions
diff --git a/drivers/usb/phy/phy-generic.c b/drivers/usb/phy/phy-generic.c index 89d6e7a5fdb7..08b8875ac520 100644 --- a/drivers/usb/phy/phy-generic.c +++ b/drivers/usb/phy/phy-generic.c @@ -57,28 +57,35 @@ void usb_phy_generic_unregister(struct platform_device *pdev) } EXPORT_SYMBOL_GPL(usb_phy_generic_unregister); -static int nop_set_suspend(struct usb_phy *x, int suspend) +static void nop_reset(struct usb_phy_generic *nop) { - struct usb_phy_generic *nop = dev_get_drvdata(x->dev); + if (!nop->gpiod_reset) + return; - if (!IS_ERR(nop->clk)) { - if (suspend) - clk_disable_unprepare(nop->clk); - else - clk_prepare_enable(nop->clk); - } + dev_dbg(nop->dev, "reset\n"); - return 0; + gpiod_set_value_cansleep(nop->gpiod_reset, 1); + usleep_range(10000, 20000); + gpiod_set_value_cansleep(nop->gpiod_reset, 0); } -static void nop_reset(struct usb_phy_generic *nop) +static int nop_set_suspend(struct usb_phy *x, int suspend) { - if (!nop->gpiod_reset) - return; + struct usb_phy_generic *nop = dev_get_drvdata(x->dev); - gpiod_set_value(nop->gpiod_reset, 1); - usleep_range(10000, 20000); - gpiod_set_value(nop->gpiod_reset, 0); + dev_dbg(x->dev, "%s\n", suspend ? "suspend" : "resume"); + + if (suspend) { + if (!IS_ERR(nop->clk)) + clk_disable_unprepare(nop->clk); + } else { + if (!IS_ERR(nop->clk)) + clk_prepare_enable(nop->clk); + + if (nop->reset_on_resume) + nop_reset(nop); + } + return 0; } /* interface to regulator framework */ @@ -172,7 +179,7 @@ void usb_gen_phy_shutdown(struct usb_phy *phy) { struct usb_phy_generic *nop = dev_get_drvdata(phy->dev); - gpiod_set_value(nop->gpiod_reset, 1); + gpiod_set_value_cansleep(nop->gpiod_reset, 1); if (!IS_ERR(nop->clk)) clk_disable_unprepare(nop->clk); @@ -232,6 +239,9 @@ int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop, if (of_property_read_u32(node, "clock-frequency", &clk_rate)) clk_rate = 0; + nop->reset_on_resume = + of_property_read_bool(node, "reset-on-resume"); + needs_vcc = of_property_read_bool(node, "vcc-supply"); nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset", GPIOD_ASIS); @@ -241,6 +251,8 @@ int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop, "vbus-detect", GPIOD_ASIS); err = PTR_ERR_OR_ZERO(nop->gpiod_vbus); + } else { + nop->gpiod_reset = NULL; } } else if (pdata) { type = pdata->type; diff --git a/drivers/usb/phy/phy-generic.h b/drivers/usb/phy/phy-generic.h index 97289627561d..9ddca95fad33 100644 --- a/drivers/usb/phy/phy-generic.h +++ b/drivers/usb/phy/phy-generic.h @@ -15,6 +15,7 @@ struct usb_phy_generic { struct gpio_desc *gpiod_vbus; struct regulator *vbus_draw; bool vbus_draw_enabled; + bool reset_on_resume; unsigned long mA; unsigned int vbus; }; |