target/linux/apm821xx/patches-5.4/104-usb-xhci-provide-a-debugfs-hook-for-erasing-rom.patch

   1 From d6e220fb600a6b1f73155b541aa9826ec75d4559 Mon Sep 17 00:00:00 2001
   2 From: Vinod Koul <vkoul@kernel.org>
   3 Date: Mon, 13 Jan 2020 14:10:05 +0530
   4 Subject: [PATCH 104/104] usb: xhci: provide a debugfs hook for erasing rom
   5
   6 run "echo 1 > /sys/kernel/debug/renesas-usb/rom_erase" to erase firmware
   7 when driver is loaded.
   8
   9 Subsequent init of driver shall reload the firmware
  10
  11 Signed-off-by: Vinod Koul <vkoul@kernel.org>
  12 Signed-off-by: Christian Lamparter <chunkeey@gmail.com> [5.4 backport]
  13 ---
  14  drivers/usb/host/xhci-pci-renesas.c | 35 +++++++++++++++++++++++++++++
  15  1 file changed, 35 insertions(+)
  16
  17 --- a/drivers/usb/host/xhci-pci-renesas.c
  18 +++ b/drivers/usb/host/xhci-pci-renesas.c
  19 @@ -2,6 +2,7 @@
  20  /* Copyright (C) 2019-2020 Linaro Limited */
  21
  22  #include <linux/acpi.h>
  23 +#include <linux/debugfs.h>
  24  #include <linux/firmware.h>
  25  #include <linux/module.h>
  26  #include <linux/pci.h>
  27 @@ -229,6 +230,9 @@ static int renesas_fw_verify(struct pci_
  28
  29         return 0;
  30  }
  31 +
  32 +static void debugfs_init(struct pci_dev *pdev);
  33 +
  34  static int renesas_check_rom_state(struct pci_dev *pdev)
  35  {
  36         const struct renesas_fw_entry *entry;
  37 @@ -252,6 +256,7 @@ static int renesas_check_rom_state(struc
  38                 if (version == entry->expected_version) {
  39                         dev_dbg(&pdev->dev, "Detected valid ROM version..\n");
  40                         valid_version = true;
  41 +                       debugfs_init(pdev);
  42                 }
  43         }
  44         if (valid_version == false)
  45 @@ -536,6 +541,34 @@ static void renesas_rom_erase(struct pci
  46         dev_dbg(&pdev->dev, "ROM Erase... Done success\n");
  47  }
  48
  49 +static int debugfs_rom_erase(void *data, u64 value)
  50 +{
  51 +       struct pci_dev *pdev = data;
  52 +
  53 +       if (value == 1) {
  54 +               dev_dbg(&pdev->dev, "Userspace requested ROM erase\n");
  55 +               renesas_rom_erase(pdev);
  56 +               return 0;
  57 +       }
  58 +       return -EINVAL;
  59 +}
  60 +DEFINE_DEBUGFS_ATTRIBUTE(rom_erase_ops, NULL, debugfs_rom_erase, "%llu\n");
  61 +
  62 +static struct dentry *debugfs_root;
  63 +
  64 +static void debugfs_init(struct pci_dev *pdev)
  65 +{
  66 +       debugfs_root = debugfs_create_dir("renesas-usb", NULL);
  67 +
  68 +       debugfs_create_file("rom_erase", 0200, debugfs_root,
  69 +                           pdev, &rom_erase_ops);
  70 +}
  71 +
  72 +static void debugfs_exit(void)
  73 +{
  74 +       debugfs_remove_recursive(debugfs_root);
  75 +}
  76 +
  77  static bool renesas_download_rom(struct pci_dev *pdev,
  78                                  const u32 *fw, size_t step)
  79  {
  80 @@ -889,6 +922,8 @@ static int renesas_xhci_pci_probe(struct
  81
  82  static void renesas_xhci_pci_remove(struct pci_dev *dev)
  83  {
  84 +       debugfs_exit();
  85 +
  86         if (renesas_fw_alive_check(dev)) {
  87                 /*
  88                  * bail out early, if this was a renesas device w/o FW.