Hi Thierry, Thanks for review. I will amend accordingly and submit a new revision. JC On 8/31/20 8:50 PM, Thierry Reding wrote: > On Mon, Aug 31, 2020 at 12:40:43PM +0800, JC Kuo wrote: >> This commit implements the complete programming sequence for ELPG >> entry and exit. >> >> 1. At ELPG entry, invokes tegra_xusb_padctl_enable_phy_sleepwalk() >> and tegra_xusb_padctl_enable_phy_wake() to configure XUSB PADCTL >> sleepwalk and wake detection circuits to maintain USB lines level >> and respond to wake events (wake-on-connect, wake-on-disconnect, >> device-initiated-wake). >> >> 2. At ELPG exit, invokes tegra_xusb_padctl_disable_phy_sleepwalk() >> and tegra_xusb_padctl_disable_phy_wake() to disarm sleepwalk and >> wake detection circuits. >> >> At runtime suspend, XUSB host controller can enter ELPG to reduce >> power consumption. When XUSB PADCTL wake detection circuit detects >> a wake event, an interrupt will be raised. xhci-tegra driver then >> will invoke pm_runtime_resume() for xhci-tegra. >> >> Runtime resume could also be triggered by protocol drivers, this is >> the host-initiated-wake event. At runtime resume, xhci-tegra driver >> brings XUSB host controller out of ELPG to handle the wake events. >> >> The same ELPG enter/exit procedure will be performed for system >> suspend/resume path so USB devices can remain connected across SC7. >> >> Signed-off-by: JC Kuo <jckuo@xxxxxxxxxx> >> --- >> drivers/usb/host/xhci-tegra.c | 391 +++++++++++++++++++++++++++++++--- >> 1 file changed, 361 insertions(+), 30 deletions(-) >> >> diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c >> index ce6526c2caf6..9530cfc83f45 100644 >> --- a/drivers/usb/host/xhci-tegra.c >> +++ b/drivers/usb/host/xhci-tegra.c >> @@ -15,9 +15,11 @@ >> #include <linux/kernel.h> >> #include <linux/module.h> >> #include <linux/of_device.h> >> +#include <linux/of_irq.h> >> #include <linux/phy/phy.h> >> #include <linux/phy/tegra/xusb.h> >> #include <linux/platform_device.h> >> +#include <linux/usb/ch9.h> >> #include <linux/pm.h> >> #include <linux/pm_domain.h> >> #include <linux/pm_runtime.h> >> @@ -224,6 +226,7 @@ struct tegra_xusb { >> >> int xhci_irq; >> int mbox_irq; >> + int padctl_irq; >> >> void __iomem *ipfs_base; >> void __iomem *fpci_base; >> @@ -268,10 +271,13 @@ struct tegra_xusb { >> dma_addr_t phys; >> } fw; >> >> + bool suspended; >> struct tegra_xusb_context context; >> }; >> >> static struct hc_driver __read_mostly tegra_xhci_hc_driver; >> +static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool runtime); >> +static int tegra_xusb_enter_elpg(struct tegra_xusb *tegra, bool runtime); >> >> static inline u32 fpci_readl(struct tegra_xusb *tegra, unsigned int offset) >> { >> @@ -657,6 +663,9 @@ static irqreturn_t tegra_xusb_mbox_thread(int irq, void *data) >> >> mutex_lock(&tegra->lock); >> >> + if (pm_runtime_suspended(tegra->dev) || tegra->suspended) >> + goto out; >> + >> value = fpci_readl(tegra, tegra->soc->mbox.data_out); >> tegra_xusb_mbox_unpack(&msg, value); >> >> @@ -670,6 +679,7 @@ static irqreturn_t tegra_xusb_mbox_thread(int irq, void *data) >> >> tegra_xusb_mbox_handle(tegra, &msg); >> >> +out: >> mutex_unlock(&tegra->lock); >> return IRQ_HANDLED; >> } >> @@ -812,12 +822,27 @@ static void tegra_xusb_phy_disable(struct tegra_xusb *tegra) >> >> static int tegra_xusb_runtime_suspend(struct device *dev) >> { >> - return 0; >> + struct tegra_xusb *tegra = dev_get_drvdata(dev); >> + int ret; >> + >> + synchronize_irq(tegra->mbox_irq); >> + mutex_lock(&tegra->lock); >> + ret = tegra_xusb_enter_elpg(tegra, true); >> + mutex_unlock(&tegra->lock); >> + >> + return ret; >> } >> >> static int tegra_xusb_runtime_resume(struct device *dev) >> { >> - return 0; >> + struct tegra_xusb *tegra = dev_get_drvdata(dev); >> + int err; >> + >> + mutex_lock(&tegra->lock); >> + err = tegra_xusb_exit_elpg(tegra, true); >> + mutex_unlock(&tegra->lock); >> + >> + return err; >> } >> >> #ifdef CONFIG_PM_SLEEP >> @@ -1121,6 +1146,22 @@ static int __tegra_xusb_enable_firmware_messages(struct tegra_xusb *tegra) >> return err; >> } >> >> +static irqreturn_t tegra_xusb_padctl_irq(int irq, void *data) >> +{ >> + struct tegra_xusb *tegra = data; >> + >> + mutex_lock(&tegra->lock); >> + if (tegra->suspended) { >> + mutex_unlock(&tegra->lock); >> + return IRQ_HANDLED; >> + } >> + mutex_unlock(&tegra->lock); > > Blank lines before and after a block can help make this less cluttered. > >> + >> + pm_runtime_resume(tegra->dev); >> + >> + return IRQ_HANDLED; >> +} >> + >> static int tegra_xusb_enable_firmware_messages(struct tegra_xusb *tegra) >> { >> int err; >> @@ -1244,6 +1285,51 @@ static void tegra_xhci_id_work(struct work_struct *work) >> } >> } >> >> +static bool is_usb2_otg_phy(struct tegra_xusb *tegra, int index) > > unsigned int index? > >> +{ >> + return (tegra->usbphy[index] != NULL); >> +} >> + >> +static bool is_usb3_otg_phy(struct tegra_xusb *tegra, int index) > > Here too. > >> +{ >> + struct tegra_xusb_padctl *padctl = tegra->padctl; >> + int i, port; > > These can also be unsigned. > >> + >> + for (i = 0; i < tegra->num_usb_phys; i++) { >> + if (is_usb2_otg_phy(tegra, i)) { >> + port = tegra_xusb_padctl_get_usb3_companion(padctl,i); > > Space after ",". > >> + if (index == port) >> + return true; >> + } >> + } >> + >> + return false; >> +} >> + >> +static bool is_host_mode_phy(struct tegra_xusb *tegra, int phy_type, int index) >> +{ >> + if (strcmp(tegra->soc->phy_types[phy_type].name, "hsic") == 0) >> + return true; >> + >> + if (strcmp(tegra->soc->phy_types[phy_type].name, "usb2") == 0) { >> + if (is_usb2_otg_phy(tegra, index)) { >> + return ((index == tegra->otg_usb2_port) && >> + tegra->host_mode); >> + } else >> + return true; >> + } >> + >> + if (strcmp(tegra->soc->phy_types[phy_type].name, "usb3") == 0) { >> + if (is_usb3_otg_phy(tegra, index)) { >> + return ((index == tegra->otg_usb3_port) && >> + tegra->host_mode); >> + } else >> + return true; >> + } >> + >> + return false; >> +} >> + >> static int tegra_xusb_get_usb2_port(struct tegra_xusb *tegra, >> struct usb_phy *usbphy) >> { >> @@ -1336,6 +1422,7 @@ static void tegra_xusb_deinit_usb_phy(struct tegra_xusb *tegra) >> static int tegra_xusb_probe(struct platform_device *pdev) >> { >> struct tegra_xusb *tegra; >> + struct device_node *np; >> struct resource *regs; >> struct xhci_hcd *xhci; >> unsigned int i, j, k; >> @@ -1383,6 +1470,14 @@ static int tegra_xusb_probe(struct platform_device *pdev) >> if (IS_ERR(tegra->padctl)) >> return PTR_ERR(tegra->padctl); >> >> + np = of_parse_phandle(pdev->dev.of_node, "nvidia,xusb-padctl", 0); >> + if (!np) >> + return -ENODEV; >> + >> + tegra->padctl_irq = of_irq_get(np, 0); >> + if (tegra->padctl_irq < 0) >> + return tegra->padctl_irq; >> + >> tegra->host_clk = devm_clk_get(&pdev->dev, "xusb_host"); >> if (IS_ERR(tegra->host_clk)) { >> err = PTR_ERR(tegra->host_clk); >> @@ -1527,6 +1622,7 @@ static int tegra_xusb_probe(struct platform_device *pdev) >> goto put_powerdomains; >> } >> >> + tegra->hcd->skip_phy_initialization = 1; >> tegra->hcd->regs = tegra->regs; >> tegra->hcd->rsrc_start = regs->start; >> tegra->hcd->rsrc_len = resource_size(regs); >> @@ -1609,12 +1705,6 @@ static int tegra_xusb_probe(struct platform_device *pdev) >> goto put_usb3; >> } >> >> - err = tegra_xusb_enable_firmware_messages(tegra); >> - if (err < 0) { >> - dev_err(&pdev->dev, "failed to enable messages: %d\n", err); >> - goto remove_usb3; >> - } >> - >> err = devm_request_threaded_irq(&pdev->dev, tegra->mbox_irq, >> tegra_xusb_mbox_irq, >> tegra_xusb_mbox_thread, 0, >> @@ -1624,12 +1714,40 @@ static int tegra_xusb_probe(struct platform_device *pdev) >> goto remove_usb3; >> } >> >> + err = devm_request_threaded_irq(&pdev->dev, tegra->padctl_irq, >> + NULL, >> + tegra_xusb_padctl_irq, >> + IRQF_ONESHOT | >> + IRQF_TRIGGER_HIGH, >> + dev_name(&pdev->dev), tegra); > > The alignment here is off. Also, try to make good use of those 100 > columns. > >> + if (err < 0) { >> + dev_err(&pdev->dev, "failed to request padctl IRQ: %d\n", err); >> + goto remove_usb3; >> + } >> + >> + err = tegra_xusb_enable_firmware_messages(tegra); >> + if (err < 0) { >> + dev_err(&pdev->dev, "failed to enable messages: %d\n", err); >> + goto remove_usb3; >> + } >> + >> err = tegra_xusb_init_usb_phy(tegra); >> if (err < 0) { >> dev_err(&pdev->dev, "failed to init USB PHY: %d\n", err); >> goto remove_usb3; >> } >> >> + /* Enable wake for both USB 2.0 and USB 3.0 roothubs */ >> + device_init_wakeup(&tegra->hcd->self.root_hub->dev, true); >> + device_init_wakeup(&xhci->shared_hcd->self.root_hub->dev, true); >> + device_init_wakeup(tegra->dev, true); >> + >> + pm_runtime_use_autosuspend(tegra->dev); >> + pm_runtime_set_autosuspend_delay(tegra->dev, 2000); >> + pm_runtime_mark_last_busy(tegra->dev); >> + pm_runtime_set_active(tegra->dev); >> + pm_runtime_enable(tegra->dev); >> + >> return 0; >> >> remove_usb3: >> @@ -1665,6 +1783,7 @@ static int tegra_xusb_remove(struct platform_device *pdev) >> >> tegra_xusb_deinit_usb_phy(tegra); >> >> + pm_runtime_get_sync(&pdev->dev); >> usb_remove_hcd(xhci->shared_hcd); >> usb_put_hcd(xhci->shared_hcd); >> xhci->shared_hcd = NULL; >> @@ -1674,8 +1793,8 @@ static int tegra_xusb_remove(struct platform_device *pdev) >> dma_free_coherent(&pdev->dev, tegra->fw.size, tegra->fw.virt, >> tegra->fw.phys); >> >> - pm_runtime_put_sync(&pdev->dev); >> pm_runtime_disable(&pdev->dev); >> + pm_runtime_put(&pdev->dev); >> >> tegra_xusb_powergate_partitions(tegra); >> >> @@ -1717,9 +1836,17 @@ static bool xhci_hub_ports_suspended(struct xhci_hub *hub) >> static int tegra_xusb_check_ports(struct tegra_xusb *tegra) >> { >> struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd); >> + struct xhci_hub *rhub = xhci_get_rhub(xhci->main_hcd); >> + struct xhci_bus_state *bus_state = &rhub->bus_state; >> unsigned long flags; >> int err = 0; >> >> + if (bus_state->bus_suspended) { >> + /* xusb_hub_suspend() has just directed one or more USB2 port(s) >> + * to U3 state, it takes 3ms to enter U3. */ >> + usleep_range(3000, 4000); >> + } >> + >> spin_lock_irqsave(&xhci->lock, flags); >> >> if (!xhci_hub_ports_suspended(&xhci->usb2_rhub) || >> @@ -1765,45 +1892,184 @@ static void tegra_xusb_restore_context(struct tegra_xusb *tegra) >> } >> } >> >> -static int tegra_xusb_enter_elpg(struct tegra_xusb *tegra, bool wakeup) >> +static enum usb_device_speed >> +tegra_xhci_portsc_to_speed(struct tegra_xusb *tegra, u32 portsc) >> +{ >> + if (DEV_LOWSPEED(portsc)) >> + return USB_SPEED_LOW; >> + else if (DEV_HIGHSPEED(portsc)) >> + return USB_SPEED_HIGH; >> + else if (DEV_FULLSPEED(portsc)) >> + return USB_SPEED_FULL; >> + else if (DEV_SUPERSPEED_ANY(portsc)) >> + return USB_SPEED_SUPER; >> + else >> + return USB_SPEED_UNKNOWN; >> +} > > As in a prior patch you can make this simpler by dropping the elses. > >> + >> +static void tegra_xhci_enable_phy_sleepwalk_wake(struct tegra_xusb *tegra) >> +{ >> + struct tegra_xusb_padctl *padctl = tegra->padctl; >> + struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd); >> + enum usb_device_speed speed; >> + struct phy *phy; >> + int index, offset; >> + int i, j, k; > > It looks like these can all be unsigned int. > >> + struct xhci_hub *rhub; >> + u32 portsc; >> + >> + for (i = 0, k = 0; i < tegra->soc->num_types; i++) { >> + if (strcmp(tegra->soc->phy_types[i].name, "usb3") == 0) >> + rhub = &xhci->usb3_rhub; >> + else >> + rhub = &xhci->usb2_rhub; >> + >> + if (strcmp(tegra->soc->phy_types[i].name, "hsic") == 0) >> + offset = tegra->soc->ports.usb2.count; >> + else >> + offset = 0; >> + >> + for (j = 0; j < tegra->soc->phy_types[i].num; j++) { >> + phy = tegra->phys[k++]; >> + >> + if (!phy) >> + continue; >> + >> + index = j + offset; >> + >> + if (index >= rhub->num_ports) >> + continue; >> + >> + if (!is_host_mode_phy(tegra, i, j)) >> + continue; >> + >> + portsc = readl(rhub->ports[index]->addr); >> + speed = tegra_xhci_portsc_to_speed(tegra, portsc); >> + tegra_xusb_padctl_enable_phy_sleepwalk(padctl, phy, >> + speed); >> + tegra_xusb_padctl_enable_phy_wake(padctl, phy); >> + } >> + } >> +} >> + >> +static void tegra_xhci_disable_phy_wake(struct tegra_xusb *tegra) >> +{ >> + struct tegra_xusb_padctl *padctl = tegra->padctl; >> + int i; > > Same here. > >> + >> + for (i = 0; i < tegra->num_phys; i++) { >> + if (!tegra->phys[i]) >> + continue; >> + >> + tegra_xusb_padctl_disable_phy_wake(padctl, tegra->phys[i]); >> + } >> +} >> + >> +static void tegra_xhci_disable_phy_sleepwalk(struct tegra_xusb *tegra) >> +{ >> + struct tegra_xusb_padctl *padctl = tegra->padctl; >> + int i; > > And here. > >> + >> + for (i = 0; i < tegra->num_phys; i++) { >> + if (!tegra->phys[i]) >> + continue; >> + >> + tegra_xusb_padctl_disable_phy_sleepwalk(padctl, tegra->phys[i]); >> + } >> +} >> + >> +static int tegra_xusb_enter_elpg(struct tegra_xusb *tegra, bool runtime) >> { >> struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd); >> + struct device *dev = tegra->dev; >> + bool wakeup = runtime ? true : device_may_wakeup(dev); >> + unsigned int i; >> int err; >> + u32 usbcmd; >> + >> + dev_dbg(dev, "entering ELPG\n"); >> + >> + usbcmd = readl(&xhci->op_regs->command); >> + usbcmd &= ~CMD_EIE; >> + writel(usbcmd, &xhci->op_regs->command); >> >> err = tegra_xusb_check_ports(tegra); >> if (err < 0) { >> dev_err(tegra->dev, "not all ports suspended: %d\n", err); >> - return err; >> + goto out; >> } >> >> err = xhci_suspend(xhci, wakeup); >> if (err < 0) { >> dev_err(tegra->dev, "failed to suspend XHCI: %d\n", err); >> - return err; >> + goto out; >> } >> >> tegra_xusb_save_context(tegra); >> - tegra_xusb_phy_disable(tegra); >> + >> + if (wakeup) >> + tegra_xhci_enable_phy_sleepwalk_wake(tegra); >> + >> + tegra_xusb_powergate_partitions(tegra); >> + >> + for (i = 0; i < tegra->num_phys; i++) { >> + if (!tegra->phys[i]) >> + continue; >> + >> + phy_power_off(tegra->phys[i]); >> + if (!wakeup) >> + phy_exit(tegra->phys[i]); >> + } >> tegra_xusb_clk_disable(tegra); > > Use blank lines to separate blocks of code. > >> >> - return 0; >> +out: >> + if (!err) >> + dev_dbg(tegra->dev, "entering ELPG done\n"); >> + else { >> + usbcmd = readl(&xhci->op_regs->command); >> + usbcmd |= CMD_EIE; >> + writel(usbcmd, &xhci->op_regs->command); >> + >> + dev_dbg(tegra->dev, "entering ELPG failed\n"); >> + pm_runtime_mark_last_busy(tegra->dev); >> + } >> + >> + return err; >> } >> >> -static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool wakeup) >> +static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool runtime) >> { >> struct xhci_hcd *xhci = hcd_to_xhci(tegra->hcd); >> + struct device *dev = tegra->dev; >> + bool wakeup = runtime ? true : device_may_wakeup(dev); >> + unsigned int i; >> + u32 usbcmd; >> int err; >> >> + dev_dbg(dev, "exiting ELPG\n"); >> + pm_runtime_mark_last_busy(tegra->dev); >> + >> err = tegra_xusb_clk_enable(tegra); >> if (err < 0) { >> dev_err(tegra->dev, "failed to enable clocks: %d\n", err); >> - return err; >> + goto out; >> } >> >> - err = tegra_xusb_phy_enable(tegra); >> - if (err < 0) { >> - dev_err(tegra->dev, "failed to enable PHYs: %d\n", err); >> - goto disable_clk; >> + err = tegra_xusb_unpowergate_partitions(tegra); >> + if (err) >> + goto disable_clks; >> + >> + if (wakeup) >> + tegra_xhci_disable_phy_wake(tegra); >> + >> + for (i = 0; i < tegra->num_phys; i++) { >> + if (!tegra->phys[i]) >> + continue; >> + >> + if (!wakeup) >> + phy_init(tegra->phys[i]); >> + >> + phy_power_on(tegra->phys[i]); >> } >> >> tegra_xusb_config(tegra); >> @@ -1821,31 +2087,78 @@ static int tegra_xusb_exit_elpg(struct tegra_xusb *tegra, bool wakeup) >> goto disable_phy; >> } >> >> - err = xhci_resume(xhci, true); >> + if (wakeup) >> + tegra_xhci_disable_phy_sleepwalk(tegra); >> + >> + err = xhci_resume(xhci, 0); >> if (err < 0) { >> dev_err(tegra->dev, "failed to resume XHCI: %d\n", err); >> goto disable_phy; >> } >> >> - return 0; >> + usbcmd = readl(&xhci->op_regs->command); >> + usbcmd |= CMD_EIE; >> + writel(usbcmd, &xhci->op_regs->command); >> + >> + goto out; >> >> disable_phy: >> - tegra_xusb_phy_disable(tegra); >> -disable_clk: >> + for (i = 0; i < tegra->num_phys; i++) { >> + if (!tegra->phys[i]) >> + continue; >> + >> + phy_power_off(tegra->phys[i]); >> + if (!wakeup) >> + phy_exit(tegra->phys[i]); >> + } >> + tegra_xusb_powergate_partitions(tegra); >> +disable_clks: >> tegra_xusb_clk_disable(tegra); >> +out: >> + if (!err) >> + dev_dbg(dev, "exiting ELPG done\n"); >> + else >> + dev_dbg(dev, "exiting ELPG failed\n"); >> + >> return err; >> } >> >> static int tegra_xusb_suspend(struct device *dev) >> { >> struct tegra_xusb *tegra = dev_get_drvdata(dev); >> - bool wakeup = device_may_wakeup(dev); >> int err; >> >> synchronize_irq(tegra->mbox_irq); >> - > > I think that blank line actually helped with readability. > > Thierry > >> mutex_lock(&tegra->lock); >> - err = tegra_xusb_enter_elpg(tegra, wakeup); >> + >> + if (pm_runtime_suspended(dev)) { >> + err = tegra_xusb_exit_elpg(tegra, true); >> + if (err < 0) >> + goto out; >> + } >> + >> + err = tegra_xusb_enter_elpg(tegra, false); >> + if (err < 0) { >> + if (pm_runtime_suspended(dev)) { >> + pm_runtime_disable(dev); >> + pm_runtime_set_active(dev); >> + pm_runtime_enable(dev); >> + } >> + >> + goto out; >> + } >> + >> +out: >> + if (!err) { >> + tegra->suspended = true; >> + pm_runtime_disable(dev); >> + >> + if (device_may_wakeup(dev)) { >> + if (enable_irq_wake(tegra->padctl_irq)) >> + dev_err(dev, "failed to enable padctl wakes\n"); >> + } >> + } >> + >> mutex_unlock(&tegra->lock); >> >> return err; >> @@ -1854,14 +2167,32 @@ static int tegra_xusb_suspend(struct device *dev) >> static int tegra_xusb_resume(struct device *dev) >> { >> struct tegra_xusb *tegra = dev_get_drvdata(dev); >> - bool wakeup = device_may_wakeup(dev); >> int err; >> >> mutex_lock(&tegra->lock); >> - err = tegra_xusb_exit_elpg(tegra, wakeup); >> + >> + if (!tegra->suspended) { >> + mutex_unlock(&tegra->lock); >> + return 0; >> + } >> + >> + err = tegra_xusb_exit_elpg(tegra, false); >> + if (err < 0) { >> + mutex_unlock(&tegra->lock); >> + return err; >> + } >> + >> + if (device_may_wakeup(dev)) { >> + if (disable_irq_wake(tegra->padctl_irq)) >> + dev_err(dev, "failed to disable padctl wakes\n"); >> + } >> + tegra->suspended = false; >> mutex_unlock(&tegra->lock); >> >> - return err; >> + pm_runtime_set_active(dev); >> + pm_runtime_enable(dev); >> + >> + return 0; >> } >> #endif >> >> -- >> 2.25.1 >>