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);
projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / commitdiff