diff options
| -rw-r--r-- | drivers/usb/host/xhci-pci.c | 9 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.c | 319 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.h | 7 |
3 files changed, 335 insertions, 0 deletions
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index 19e89216436e..890ba735dee7 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -170,6 +170,13 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) if (retval) goto put_usb3_hcd; /* Roothub already marked as USB 3.0 speed */ + + /* We know the LPM timeout algorithms for this host, let the USB core + * enable and disable LPM for devices under the USB 3.0 roothub. + */ + if (xhci->quirks & XHCI_LPM_SUPPORT) + hcd_to_bus(xhci->shared_hcd)->root_hub->lpm_capable = 1; + return 0; put_usb3_hcd: @@ -293,6 +300,8 @@ static const struct hc_driver xhci_pci_hc_driver = { */ .update_device = xhci_update_device, .set_usb2_hw_lpm = xhci_set_usb2_hardware_lpm, + .enable_usb3_lpm_timeout = xhci_enable_usb3_lpm_timeout, + .disable_usb3_lpm_timeout = xhci_disable_usb3_lpm_timeout, }; /*-------------------------------------------------------------------------*/ diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 05034f346fad..518d002d54cc 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -3837,6 +3837,325 @@ int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd, return 0; } +/*---------------------- USB 3.0 Link PM functions ------------------------*/ + +static u16 xhci_get_timeout_no_hub_lpm(struct usb_device *udev, + enum usb3_link_state state) +{ + unsigned long long sel; + unsigned long long pel; + unsigned int max_sel_pel; + char *state_name; + + switch (state) { + case USB3_LPM_U1: + /* Convert SEL and PEL stored in nanoseconds to microseconds */ + sel = DIV_ROUND_UP(udev->u1_params.sel, 1000); + pel = DIV_ROUND_UP(udev->u1_params.pel, 1000); + max_sel_pel = USB3_LPM_MAX_U1_SEL_PEL; + state_name = "U1"; + break; + case USB3_LPM_U2: + sel = DIV_ROUND_UP(udev->u2_params.sel, 1000); + pel = DIV_ROUND_UP(udev->u2_params.pel, 1000); + max_sel_pel = USB3_LPM_MAX_U2_SEL_PEL; + state_name = "U2"; + break; + default: + dev_warn(&udev->dev, "%s: Can't get timeout for non-U1 or U2 state.\n", + __func__); + return -EINVAL; + } + + if (sel <= max_sel_pel && pel <= max_sel_pel) + return USB3_LPM_DEVICE_INITIATED; + + if (sel > max_sel_pel) + dev_dbg(&udev->dev, "Device-initiated %s disabled " + "due to long SEL %llu ms\n", + state_name, sel); + else + dev_dbg(&udev->dev, "Device-initiated %s disabled " + "due to long PEL %llu\n ms", + state_name, pel); + return USB3_LPM_DISABLED; +} + +static u16 xhci_call_host_update_timeout_for_endpoint(struct xhci_hcd *xhci, + struct usb_device *udev, + struct usb_endpoint_descriptor *desc, + enum usb3_link_state state, + u16 *timeout) +{ + return USB3_LPM_DISABLED; +} + +static int xhci_update_timeout_for_endpoint(struct xhci_hcd *xhci, + struct usb_device *udev, + struct usb_endpoint_descriptor *desc, + enum usb3_link_state state, + u16 *timeout) +{ + u16 alt_timeout; + + alt_timeout = xhci_call_host_update_timeout_for_endpoint(xhci, udev, + desc, state, timeout); + + /* If we found we can't enable hub-initiated LPM, or + * the U1 or U2 exit latency was too high to allow + * device-initiated LPM as well, just stop searching. + */ + if (alt_timeout == USB3_LPM_DISABLED || + alt_timeout == USB3_LPM_DEVICE_INITIATED) { + *timeout = alt_timeout; + return -E2BIG; + } + if (alt_timeout > *timeout) + *timeout = alt_timeout; + return 0; +} + +static int xhci_update_timeout_for_interface(struct xhci_hcd *xhci, + struct usb_device *udev, + struct usb_host_interface *alt, + enum usb3_link_state state, + u16 *timeout) +{ + int j; + + for (j = 0; j < alt->desc.bNumEndpoints; j++) { + if (xhci_update_timeout_for_endpoint(xhci, udev, + &alt->endpoint[j].desc, state, timeout)) + return -E2BIG; + continue; + } + return 0; +} + +static int xhci_check_tier_policy(struct xhci_hcd *xhci, + struct usb_device *udev, + enum usb3_link_state state) +{ + return -EINVAL; +} + +/* Returns the U1 or U2 timeout that should be enabled. + * If the tier check or timeout setting functions return with a non-zero exit + * code, that means the timeout value has been finalized and we shouldn't look + * at any more endpoints. + */ +static u16 xhci_calculate_lpm_timeout(struct usb_hcd *hcd, + struct usb_device *udev, enum usb3_link_state state) +{ + struct xhci_hcd *xhci = hcd_to_xhci(hcd); + struct usb_host_config *config; + char *state_name; + int i; + u16 timeout = USB3_LPM_DISABLED; + + if (state == USB3_LPM_U1) + state_name = "U1"; + else if (state == USB3_LPM_U2) + state_name = "U2"; + else { + dev_warn(&udev->dev, "Can't enable unknown link state %i\n", + state); + return timeout; + } + + if (xhci_check_tier_policy(xhci, udev, state) < 0) + return timeout; + + /* Gather some information about the currently installed configuration + * and alternate interface settings. + */ + if (xhci_update_timeout_for_endpoint(xhci, udev, &udev->ep0.desc, + state, &timeout)) + return timeout; + + config = udev->actconfig; + if (!config) + return timeout; + + for (i = 0; i < USB_MAXINTERFACES; i++) { + struct usb_driver *driver; + struct usb_interface *intf = config->interface[i]; + + if (!intf) + continue; + + /* Check if any currently bound drivers want hub-initiated LPM + * disabled. + */ + if (intf->dev.driver) { + driver = to_usb_driver(intf->dev.driver); + if (driver && driver->disable_hub_initiated_lpm) { + dev_dbg(&udev->dev, "Hub-initiated %s disabled " + "at request of driver %s\n", + state_name, driver->name); + return xhci_get_timeout_no_hub_lpm(udev, state); + } + } + + /* Not sure how this could happen... */ + if (!intf->cur_altsetting) + continue; + + if (xhci_update_timeout_for_interface(xhci, udev, + intf->cur_altsetting, + state, &timeout)) + return timeout; + } + return timeout; +} + +/* + * Issue an Evaluate Context command to change the Maximum Exit Latency in the + * slot context. If that succeeds, store the new MEL in the xhci_virt_device. + */ +static int xhci_change_max_exit_latency(struct xhci_hcd *xhci, + struct usb_device *udev, u16 max_exit_latency) +{ + struct xhci_virt_device *virt_dev; + struct xhci_command *command; + struct xhci_input_control_ctx *ctrl_ctx; + struct xhci_slot_ctx *slot_ctx; + unsigned long flags; + int ret; + + spin_lock_irqsave(&xhci->lock, flags); + if (max_exit_latency == xhci->devs[udev->slot_id]->current_mel) { + spin_unlock_irqrestore(&xhci->lock, flags); + return 0; + } + + /* Attempt to issue an Evaluate Context command to change the MEL. */ + virt_dev = xhci->devs[udev->slot_id]; + command = xhci->lpm_command; + xhci_slot_copy(xhci, command->in_ctx, virt_dev->out_ctx); + spin_unlock_irqrestore(&xhci->lock, flags); + + ctrl_ctx = xhci_get_input_control_ctx(xhci, command->in_ctx); + ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG); + slot_ctx = xhci_get_slot_ctx(xhci, command->in_ctx); + slot_ctx->dev_info2 &= cpu_to_le32(~((u32) MAX_EXIT)); + slot_ctx->dev_info2 |= cpu_to_le32(max_exit_latency); + + xhci_dbg(xhci, "Set up evaluate context for LPM MEL change.\n"); + xhci_dbg(xhci, "Slot %u Input Context:\n", udev->slot_id); + xhci_dbg_ctx(xhci, command->in_ctx, 0); + + /* Issue and wait for the evaluate context command. */ + ret = xhci_configure_endpoint(xhci, udev, command, + true, true); + xhci_dbg(xhci, "Slot %u Output Context:\n", udev->slot_id); + xhci_dbg_ctx(xhci, virt_dev->out_ctx, 0); + + if (!ret) { + spin_lock_irqsave(&xhci->lock, flags); + virt_dev->current_mel = max_exit_latency; + spin_unlock_irqrestore(&xhci->lock, flags); + } + return ret; +} + +static int calculate_max_exit_latency(struct usb_device *udev, + enum usb3_link_state state_changed, + u16 hub_encoded_timeout) +{ + unsigned long long u1_mel_us = 0; + unsigned long long u2_mel_us = 0; + unsigned long long mel_us = 0; + bool disabling_u1; + bool disabling_u2; + bool enabling_u1; + bool enabling_u2; + + disabling_u1 = (state_changed == USB3_LPM_U1 && + hub_encoded_timeout == USB3_LPM_DISABLED); + disabling_u2 = (state_changed == USB3_LPM_U2 && + hub_encoded_timeout == USB3_LPM_DISABLED); + + enabling_u1 = (state_changed == USB3_LPM_U1 && + hub_encoded_timeout != USB3_LPM_DISABLED); + enabling_u2 = (state_changed == USB3_LPM_U2 && + hub_encoded_timeout != USB3_LPM_DISABLED); + + /* If U1 was already enabled and we're not disabling it, + * or we're going to enable U1, account for the U1 max exit latency. + */ + if ((udev->u1_params.timeout != USB3_LPM_DISABLED && !disabling_u1) || + enabling_u1) + u1_mel_us = DIV_ROUND_UP(udev->u1_params.mel, 1000); + if ((udev->u2_params.timeout != USB3_LPM_DISABLED && !disabling_u2) || + enabling_u2) + u2_mel_us = DIV_ROUND_UP(udev->u2_params.mel, 1000); + + if (u1_mel_us > u2_mel_us) + mel_us = u1_mel_us; + else + mel_us = u2_mel_us; + /* xHCI host controller max exit latency field is only 16 bits wide. */ + if (mel_us > MAX_EXIT) { + dev_warn(&udev->dev, "Link PM max exit latency of %lluus " + "is too big.\n", mel_us); + return -E2BIG; + } + return mel_us; +} + +/* Returns the USB3 hub-encoded value for the U1/U2 timeout. */ +int xhci_enable_usb3_lpm_timeout(struct usb_hcd *hcd, + struct usb_device *udev, enum usb3_link_state state) +{ + struct xhci_hcd *xhci; + u16 hub_encoded_timeout; + int mel; + int ret; + + xhci = hcd_to_xhci(hcd); + /* The LPM timeout values are pretty host-controller specific, so don't + * enable hub-initiated timeouts unless the vendor has provided + * information about their timeout algorithm. + */ + if (!xhci || !(xhci->quirks & XHCI_LPM_SUPPORT) || + !xhci->devs[udev->slot_id]) + return USB3_LPM_DISABLED; + + hub_encoded_timeout = xhci_calculate_lpm_timeout(hcd, udev, state); + mel = calculate_max_exit_latency(udev, state, hub_encoded_timeout); + if (mel < 0) { + /* Max Exit Latency is too big, disable LPM. */ + hub_encoded_timeout = USB3_LPM_DISABLED; + mel = 0; + } + + ret = xhci_change_max_exit_latency(xhci, udev, mel); + if (ret) + return ret; + return hub_encoded_timeout; +} + +int xhci_disable_usb3_lpm_timeout(struct usb_hcd *hcd, + struct usb_device *udev, enum usb3_link_state state) +{ + struct xhci_hcd *xhci; + u16 mel; + int ret; + + xhci = hcd_to_xhci(hcd); + if (!xhci || !(xhci->quirks & XHCI_LPM_SUPPORT) || + !xhci->devs[udev->slot_id]) + return 0; + + mel = calculate_max_exit_latency(udev, state, USB3_LPM_DISABLED); + ret = xhci_change_max_exit_latency(xhci, udev, mel); + if (ret) + return ret; + return 0; +} +/*-------------------------------------------------------------------------*/ + int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev) { struct xhci_hcd *xhci = hcd_to_xhci(hcd); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index f5cb7417f231..d55b3678c8b8 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -916,6 +916,8 @@ struct xhci_virt_device { u8 real_port; struct xhci_interval_bw_table *bw_table; struct xhci_tt_bw_info *tt_info; + /* The current max exit latency for the enabled USB3 link states. */ + u16 current_mel; }; /* @@ -1486,6 +1488,7 @@ struct xhci_hcd { #define XHCI_SW_BW_CHECKING (1 << 8) #define XHCI_AMD_0x96_HOST (1 << 9) #define XHCI_TRUST_TX_LENGTH (1 << 10) +#define XHCI_LPM_SUPPORT (1 << 11) unsigned int num_active_eps; unsigned int limit_active_eps; /* There are two roothubs to keep track of bus suspend info for */ @@ -1783,6 +1786,10 @@ void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id, /* xHCI roothub code */ void xhci_set_link_state(struct xhci_hcd *xhci, __le32 __iomem **port_array, int port_id, u32 link_state); +int xhci_enable_usb3_lpm_timeout(struct usb_hcd *hcd, + struct usb_device *udev, enum usb3_link_state state); +int xhci_disable_usb3_lpm_timeout(struct usb_hcd *hcd, + struct usb_device *udev, enum usb3_link_state state); void xhci_test_and_clear_bit(struct xhci_hcd *xhci, __le32 __iomem **port_array, int port_id, u32 port_bit); int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue, u16 wIndex, |