diff options
| author | Niklas Neronin <niklas.neronin@linux.intel.com> | 2025-11-19 16:24:08 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-11-21 14:53:00 +0100 |
| commit | 70651cc3f5a4c7cec529f121e36ea3b45ea84778 (patch) | |
| tree | 99d0233b5fb1293889bb9a5f3e128373c4cbb608 /drivers/usb/host | |
| parent | 2085fa6c0f337dc30bb869bceceb641a48f03f0a (diff) | |
usb: xhci: use cached HCSPARAMS1 value
The Structural Parameters 1 (HCSPARAMS1) register is read and cached in
'xhci->hcs_params1' during host controller initialization. Since this
register is read-only and its value remains constant for the lifetime of
the controller, re-reading it later is unnecessary.
Replace subsequent register reads with the cached 'xhci->hcs_params1'
value to avoid redundant MMIO access.
Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20251119142417.2820519-15-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host')
| -rw-r--r-- | drivers/usb/host/xhci.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 7ac8198d0d7b..dbe64ea47936 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4235,8 +4235,7 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev) xhci_err(xhci, "Error while assigning device slot ID: %s\n", xhci_trb_comp_code_string(command->status)); xhci_err(xhci, "Max number of devices this xHCI host supports is %u.\n", - HCS_MAX_SLOTS( - readl(&xhci->cap_regs->hcs_params1))); + HCS_MAX_SLOTS(xhci->hcs_params1)); xhci_free_command(xhci, command); return 0; } |