git.openwrt.org Git - openwrt/staging/neocturne.git/blob

   1 From ec51fbd1b8a2bca2948dede99c14ec63dc57ff6b Mon Sep 17 00:00:00 2001
   2 From: Bjørn Mork <bjorn@mork.no>
   3 Date: Fri, 6 Jan 2023 17:07:38 +0100
   4 Subject: [PATCH] r8152: add USB device driver for config selection
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Subclassing the generic USB device driver to override the
  10 default configuration selection regardless of matching interface
  11 drivers.
  12
  13 The r815x family devices expose a vendor specific function which
  14 the r8152 interface driver wants to handle.  This is the preferred
  15 device mode. Additionally one or more USB class functions are
  16 usually supported for hosts lacking a vendor specific driver. The
  17 choice is USB configuration based, with one alternate function per
  18 configuration.
  19
  20 Example device with both NCM and ECM alternate cfgs:
  21
  22 T:  Bus=02 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#=  4 Spd=5000 MxCh= 0
  23 D:  Ver= 3.20 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 9 #Cfgs=  3
  24 P:  Vendor=0bda ProdID=8156 Rev=31.00
  25 S:  Manufacturer=Realtek
  26 S:  Product=USB 10/100/1G/2.5G LAN
  27 S:  SerialNumber=001000001
  28 C:* #Ifs= 1 Cfg#= 1 Atr=a0 MxPwr=256mA
  29 I:* If#= 0 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=ff Prot=00 Driver=r8152
  30 E:  Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  31 E:  Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  32 E:  Ad=83(I) Atr=03(Int.) MxPS=   2 Ivl=128ms
  33 C:  #Ifs= 2 Cfg#= 2 Atr=a0 MxPwr=256mA
  34 I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=0d Prot=00 Driver=
  35 E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=128ms
  36 I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=01 Driver=
  37 I:  If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=01 Driver=
  38 E:  Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  39 E:  Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  40 C:  #Ifs= 2 Cfg#= 3 Atr=a0 MxPwr=256mA
  41 I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=06 Prot=00 Driver=
  42 E:  Ad=83(I) Atr=03(Int.) MxPS=  16 Ivl=128ms
  43 I:  If#= 1 Alt= 0 #EPs= 0 Cls=0a(data ) Sub=00 Prot=00 Driver=
  44 I:  If#= 1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=
  45 E:  Ad=81(I) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  46 E:  Ad=02(O) Atr=02(Bulk) MxPS=1024 Ivl=0ms
  47
  48 A problem with this is that Linux will prefer class functions over
  49 vendor specific functions. Using the above example, Linux defaults
  50 to cfg #2, running the device in a sub-optimal NCM mode.
  51
  52 Previously we've attempted to work around the problem by
  53 blacklisting the devices in the ECM class driver "cdc_ether", and
  54 matching on the ECM class function in the vendor specific interface
  55 driver. The latter has been used to switch back to the vendor
  56 specific configuration when the driver is probed for a class
  57 function.
  58
  59 This workaround has several issues;
  60 - class driver blacklists is additional maintanence cruft in an
  61   unrelated driver
  62 - class driver blacklists prevents users from optionally running
  63   the devices in class mode
  64 - each device needs double match entries in the vendor driver
  65 - the initial probing as a class function slows down device
  66   discovery
  67
  68 Now these issues have become even worse with the introduction of
  69 firmware supporting both NCM and ECM, where NCM ends up as the
  70 default mode in Linux. To use the same workaround, we now have
  71 to blacklist the devices in to two different class drivers and
  72 add yet another match entry to the vendor specific driver.
  73
  74 This patch implements an alternative workaround strategy -
  75 independent of the interface drivers.  It avoids adding a
  76 blacklist to the cdc_ncm driver and will let us remove the
  77 existing blacklist from the cdc_ether driver.
  78
  79 As an additional bonus, removing the blacklists allow users to
  80 select one of the other device modes if wanted.
  81
  82 Signed-off-by: Bjørn Mork <bjorn@mork.no>
  83 Signed-off-by: David S. Miller <davem@davemloft.net>
  84 ---
  85  drivers/net/usb/r8152.c | 113 ++++++++++++++++++++++++++++------------
  86  1 file changed, 81 insertions(+), 32 deletions(-)
  87
  88 --- a/drivers/net/usb/r8152.c
  89 +++ b/drivers/net/usb/r8152.c
  90 @@ -9625,6 +9625,9 @@ static int rtl8152_probe(struct usb_inte
  91         if (version == RTL_VER_UNKNOWN)
  92                 return -ENODEV;
  93
  94 +       if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
  95 +               return -ENODEV;
  96 +
  97         if (!rtl_vendor_mode(intf))
  98                 return -ENODEV;
  99
 100 @@ -9834,43 +9837,35 @@ static void rtl8152_disconnect(struct us
 101         }
 102  }
 103
 104 -#define REALTEK_USB_DEVICE(vend, prod) { \
 105 -       USB_DEVICE_INTERFACE_CLASS(vend, prod, USB_CLASS_VENDOR_SPEC), \
 106 -}, \
 107 -{ \
 108 -       USB_DEVICE_AND_INTERFACE_INFO(vend, prod, USB_CLASS_COMM, \
 109 -                       USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE), \
 110 -}
 111
 112  /* table of devices that work with this driver */
 113  static const struct usb_device_id rtl8152_table[] = {
 114         /* Realtek */
 115 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8050),
 116 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8053),
 117 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8152),
 118 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8153),
 119 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8155),
 120 -       REALTEK_USB_DEVICE(VENDOR_ID_REALTEK, 0x8156),
 121 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8050) },
 122 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8053) },
 123 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8152) },
 124 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8153) },
 125 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8155) },
 126 +       { USB_DEVICE(VENDOR_ID_REALTEK, 0x8156) },
 127
 128         /* Microsoft */
 129 -       REALTEK_USB_DEVICE(VENDOR_ID_MICROSOFT, 0x07ab),
 130 -       REALTEK_USB_DEVICE(VENDOR_ID_MICROSOFT, 0x07c6),
 131 -       REALTEK_USB_DEVICE(VENDOR_ID_MICROSOFT, 0x0927),
 132 -       REALTEK_USB_DEVICE(VENDOR_ID_MICROSOFT, 0x0c5e),
 133 -       REALTEK_USB_DEVICE(VENDOR_ID_SAMSUNG, 0xa101),
 134 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x304f),
 135 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x3054),
 136 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x3062),
 137 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x3069),
 138 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x3082),
 139 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x7205),
 140 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x720c),
 141 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x7214),
 142 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0x721e),
 143 -       REALTEK_USB_DEVICE(VENDOR_ID_LENOVO,  0xa387),
 144 -       REALTEK_USB_DEVICE(VENDOR_ID_LINKSYS, 0x0041),
 145 -       REALTEK_USB_DEVICE(VENDOR_ID_NVIDIA,  0x09ff),
 146 -       REALTEK_USB_DEVICE(VENDOR_ID_TPLINK,  0x0601),
 147 +       { USB_DEVICE(VENDOR_ID_MICROSOFT, 0x07ab) },
 148 +       { USB_DEVICE(VENDOR_ID_MICROSOFT, 0x07c6) },
 149 +       { USB_DEVICE(VENDOR_ID_MICROSOFT, 0x0927) },
 150 +       { USB_DEVICE(VENDOR_ID_SAMSUNG, 0xa101) },
 151 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x304f) },
 152 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x3054) },
 153 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x3062) },
 154 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x3069) },
 155 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x3082) },
 156 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x7205) },
 157 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x720c) },
 158 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x7214) },
 159 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0x721e) },
 160 +       { USB_DEVICE(VENDOR_ID_LENOVO,  0xa387) },
 161 +       { USB_DEVICE(VENDOR_ID_LINKSYS, 0x0041) },
 162 +       { USB_DEVICE(VENDOR_ID_NVIDIA,  0x09ff) },
 163 +       { USB_DEVICE(VENDOR_ID_TPLINK,  0x0601) },
 164         {}
 165  };
 166
 167 @@ -9890,7 +9885,61 @@ static struct usb_driver rtl8152_driver
 168         .disable_hub_initiated_lpm = 1,
 169  };
 170
 171 -module_usb_driver(rtl8152_driver);
 172 +static int rtl8152_cfgselector_probe(struct usb_device *udev)
 173 +{
 174 +       struct usb_host_config *c;
 175 +       int i, num_configs;
 176 +
 177 +       /* The vendor mode is not always config #1, so to find it out. */
 178 +       c = udev->config;
 179 +       num_configs = udev->descriptor.bNumConfigurations;
 180 +       for (i = 0; i < num_configs; (i++, c++)) {
 181 +               struct usb_interface_descriptor *desc = NULL;
 182 +
 183 +               if (!c->desc.bNumInterfaces)
 184 +                       continue;
 185 +               desc = &c->intf_cache[0]->altsetting->desc;
 186 +               if (desc->bInterfaceClass == USB_CLASS_VENDOR_SPEC)
 187 +                       break;
 188 +       }
 189 +
 190 +       if (i == num_configs)
 191 +               return -ENODEV;
 192 +
 193 +       if (usb_set_configuration(udev, c->desc.bConfigurationValue)) {
 194 +               dev_err(&udev->dev, "Failed to set configuration %d\n",
 195 +                       c->desc.bConfigurationValue);
 196 +               return -ENODEV;
 197 +       }
 198 +
 199 +       return 0;
 200 +}
 201 +
 202 +static struct usb_device_driver rtl8152_cfgselector_driver = {
 203 +       .name =         MODULENAME "-cfgselector",
 204 +       .probe =        rtl8152_cfgselector_probe,
 205 +       .id_table =     rtl8152_table,
 206 +       .generic_subclass = 1,
 207 +};
 208 +
 209 +static int __init rtl8152_driver_init(void)
 210 +{
 211 +       int ret;
 212 +
 213 +       ret = usb_register_device_driver(&rtl8152_cfgselector_driver, THIS_MODULE);
 214 +       if (ret)
 215 +               return ret;
 216 +       return usb_register(&rtl8152_driver);
 217 +}
 218 +
 219 +static void __exit rtl8152_driver_exit(void)
 220 +{
 221 +       usb_deregister(&rtl8152_driver);
 222 +       usb_deregister_device_driver(&rtl8152_cfgselector_driver);
 223 +}
 224 +
 225 +module_init(rtl8152_driver_init);
 226 +module_exit(rtl8152_driver_exit);
 227
 228  MODULE_AUTHOR(DRIVER_AUTHOR);
 229  MODULE_DESCRIPTION(DRIVER_DESC);