This patch tests USB2 software LPM for a USB2 LPM-capable device.
When a lpm-capable device is addressed, if the host also supports software
LPM, apply a test by putting the device into L1 state and resume it to see
if the device can do L1 suspend/resume successfully.
If the device fails to enter L1 or resume from L1 state, it may not
function normally and usbcore may disconnect and re-enumerate it. In this
case, store the device's Vid and Pid information, make sure the host will
not test LPM for it twice.
Signed-off-by: Andiry Xu <andiry.xu@xxxxxxx>
---
drivers/usb/host/xhci-mem.c | 10 ++++
drivers/usb/host/xhci-pci.c | 4 ++
drivers/usb/host/xhci.c | 120 +++++++++++++++++++++++++++++++++++++++++++
drivers/usb/host/xhci.h | 16 +++++-
4 files changed, 149 insertions(+), 1 deletions(-)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 83ba59b..1e066a4 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1483,6 +1483,8 @@ void xhci_free_command(struct xhci_hcd *xhci,
void xhci_mem_cleanup(struct xhci_hcd *xhci)
{
struct pci_dev *pdev = to_pci_dev(xhci_to_hcd(xhci)->self.controller);
+ struct dev_info *dev_info, *next;
+ unsigned long flags;
int size;
int i;
@@ -1540,6 +1542,13 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
scratchpad_free(xhci);
+ spin_lock_irqsave(&xhci->lock, flags);
+ list_for_each_entry_safe(dev_info, next, &xhci->lpm_failed_devs, list) {
+ list_del(&dev_info->list);
+ kfree(dev_info);
+ }
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
xhci->num_usb2_ports = 0;
xhci->num_usb3_ports = 0;
kfree(xhci->usb2_ports);
@@ -2128,6 +2137,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
if (xhci_setup_port_arrays(xhci, flags))
goto fail;
+ INIT_LIST_HEAD(&xhci->lpm_failed_devs);
xhci_calculate_hird(xhci);
return 0;
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 17541d0..bc79c9a 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -336,6 +336,10 @@ static const struct hc_driver xhci_pci_hc_driver = {
.hub_status_data = xhci_hub_status_data,
.bus_suspend = xhci_bus_suspend,
.bus_resume = xhci_bus_resume,
+ /*
+ * call back when device connected and addressed
+ */
+ .update_device = xhci_update_device,
};
/*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 95c6d91..fb636ed 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -2900,6 +2900,126 @@ int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev)
return 0;
}
+static int xhci_usb2_software_lpm_test(struct xhci_hcd *xhci,
+ struct usb_device *udev, unsigned long flags)
+{
+ struct usb_hcd *hcd = xhci_to_hcd(xhci);
+ struct dev_info *dev_info;
+ __le32 __iomem **port_array;
+ __le32 __iomem *addr, *pm_addr;
+ u32 temp, dev_id;
+ unsigned int port_num;
+ int ret;
+
+ if (hcd->speed == HCD_USB3 || !xhci->sw_lpm_support ||
+ !udev->lpm_capable)
+ return -EINVAL;
+
+ /* we only support lpm for non-hub device connected to root hub yet */
+ if (!udev->parent || udev->parent->parent ||
+ udev->descriptor.bDeviceClass == USB_CLASS_HUB)
+ return -EINVAL;
+
+ /* Look for devices in lpm_failed_devs list */
+ dev_id = le16_to_cpu(udev->descriptor.idVendor) << 16 |
+ le16_to_cpu(udev->descriptor.idProduct);
+ list_for_each_entry(dev_info, &xhci->lpm_failed_devs, list) {
+ if (dev_info->dev_id == dev_id)
+ return -EINVAL;
+ }
+
+ port_array = xhci->usb2_ports;
+ port_num = udev->portnum - 1;
+
+ if (port_num > HCS_MAX_PORTS(xhci->hcs_params1)) {
+ xhci_dbg(xhci, "invalid port number %d\n", udev->portnum);
+ return -EINVAL;
+ }
+
+ /* Test USB 2.0 software LPM */
+ xhci_dbg(xhci, "test port %d software LPM\n", port_num);
+ /* Set L1 Device Slot and HIRD */
+ pm_addr = port_array[port_num] + 1;
+ temp = PORT_L1DS(udev->slot_id) | PORT_HIRD(xhci->hird);
+ xhci_writel(xhci, temp, pm_addr);
+
+ /* Set port link state to U2(L1) */
+ addr = port_array[port_num];
+ xhci_set_link_state(xhci, port_array, port_num, XDEV_U2);
+
+ /* wait for ACK */
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ msleep(10);
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ /* Check L1 Status */
+ ret = handshake(xhci, pm_addr, PORT_L1S_MASK, PORT_L1S_SUCCESS, 125);
+ if (ret != -ETIMEDOUT) {
+ /* enter L1 successfully */
+ temp = xhci_readl(xhci, addr);
+ xhci_dbg(xhci, "port %d entered L1 state, port status 0x%x\n",
+ port_num, temp);
+ ret = 0;
+ } else {
+ temp = xhci_readl(xhci, pm_addr);
+ xhci_dbg(xhci, "port %d software lpm failed, L1 status %d\n",
+ port_num, temp & PORT_L1S_MASK);
+ ret = -EINVAL;
+ }
+
+ /* Resume the port */
+ xhci_set_link_state(xhci, port_array, port_num, XDEV_U0);
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ msleep(10);
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ /* Clear PLC */
+ xhci_test_and_clear_bit(xhci, port_array, port_num, PORT_PLC);
+
+ /* Check PORTSC to make sure the device is in the right state */
+ if (!ret) {
+ temp = xhci_readl(xhci, addr);
+ xhci_dbg(xhci, "resumed port %d status 0x%x\n", port_num, temp);
+ if (!(temp & PORT_CONNECT) || !(temp & PORT_PE) ||
+ (temp & PORT_PLS_MASK) != XDEV_U0) {
+ xhci_dbg(xhci, "port L1 resume fail\n");
+ ret = -EINVAL;
+ }
+ }
+
+ if (ret) {
+ /* Insert dev to lpm_failed_devs list */
+ xhci_warn(xhci, "device LPM test failed, may disconnect and "
+ "re-enumerate\n");
+ dev_info = kzalloc(sizeof(struct dev_info), GFP_ATOMIC);
+ if (!dev_info)
+ return -ENOMEM;
+ dev_info->dev_id = dev_id;
+ INIT_LIST_HEAD(&dev_info->list);
+ list_add(&dev_info->list, &xhci->lpm_failed_devs);
+ } else
+ xhci_ring_device(xhci, udev->slot_id);
+
+ return ret;
+}
+
+int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct xhci_hcd *xhci = hcd_to_xhci(hcd);
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ ret = xhci_usb2_software_lpm_test(xhci, udev, flags);
+ if (!ret)
+ xhci_dbg(xhci, "software LPM test succeed\n");
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ return 0;
+}
+
/* Once a hub descriptor is fetched for a device, we need to update the xHC's
* internal data structures for the device.
*/
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 983d8e8..bbaeddb 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -272,6 +272,7 @@ struct xhci_op_regs {
*/
#define PORT_PLS_MASK (0xf << 5)
#define XDEV_U0 (0x0 << 5)
+#define XDEV_U2 (0x2 << 5)
#define XDEV_U3 (0x3 << 5)
#define XDEV_RESUME (0xf << 5)
/* true: port has power (see HCC_PPC) */
@@ -362,7 +363,11 @@ struct xhci_op_regs {
/* Bits 24:31 for port testing */
/* USB2 Protocol PORTSPMSC */
-#define PORT_RWE (1 << 0x3)
+#define PORT_L1S_MASK 7
+#define PORT_L1S_SUCCESS 1
+#define PORT_RWE (1 << 3)
+#define PORT_HIRD(p) (((p) & 0xf) << 4)
+#define PORT_L1DS(p) (((p) & 0xff) << 8)
/**
* struct xhci_intr_reg - Interrupt Register Set
@@ -1196,6 +1201,12 @@ struct s3_save {
u64 erst_dequeue;
};
+/* Use for lpm */
+struct dev_info {
+ u32 dev_id;
+ struct list_head list;
+};
+
struct xhci_bus_state {
unsigned long bus_suspended;
unsigned long next_statechange;
@@ -1259,6 +1270,8 @@ struct xhci_hcd {
struct xhci_erst erst;
/* Scratchpad */
struct xhci_scratchpad *scratchpad;
+ /* Store LPM test failed devices' information */
+ struct list_head lpm_failed_devs;
/* slot enabling and address device helpers */
struct completion addr_dev;
@@ -1517,6 +1530,7 @@ int xhci_free_streams(struct usb_hcd *hcd, struct usb_device *udev,
struct usb_host_endpoint **eps, unsigned int num_eps,
gfp_t mem_flags);
int xhci_address_device(struct usb_hcd *hcd, struct usb_device *udev);
+int xhci_update_device(struct usb_hcd *hcd, struct usb_device *udev);
int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
struct usb_tt *tt, gfp_t mem_flags);
int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags);
--
1.7.1
--
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