git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 165376f6b23e9a779850e750fb2eb06622e5a531 Mon Sep 17 00:00:00 2001
   2 From: RD Babiera <rdbabiera@google.com>
   3 Date: Thu, 29 Feb 2024 00:11:02 +0000
   4 Subject: usb: typec: altmodes/displayport: create sysfs nodes as driver's default device attribute group
   5
   6 From: RD Babiera <rdbabiera@google.com>
   7
   8 commit 165376f6b23e9a779850e750fb2eb06622e5a531 upstream.
   9
  10 The DisplayPort driver's sysfs nodes may be present to the userspace before
  11 typec_altmode_set_drvdata() completes in dp_altmode_probe. This means that
  12 a sysfs read can trigger a NULL pointer error by deferencing dp->hpd in
  13 hpd_show or dp->lock in pin_assignment_show, as dev_get_drvdata() returns
  14 NULL in those cases.
  15
  16 Remove manual sysfs node creation in favor of adding attribute group as
  17 default for devices bound to the driver. The ATTRIBUTE_GROUPS() macro is
  18 not used here otherwise the path to the sysfs nodes is no longer compliant
  19 with the ABI.
  20
  21 Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode")
  22 Cc: stable@vger.kernel.org
  23 Signed-off-by: RD Babiera <rdbabiera@google.com>
  24 Link: https://lore.kernel.org/r/20240229001101.3889432-2-rdbabiera@google.com
  25 [Minor conflict resolved due to code context change.]
  26 Signed-off-by: Jianqi Ren <jianqi.ren.cn@windriver.com>
  27 Signed-off-by: He Zhe <zhe.he@windriver.com>
  28 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  29 ---
  30  drivers/usb/typec/altmodes/displayport.c |   18 +++++++++---------
  31  1 file changed, 9 insertions(+), 9 deletions(-)
  32
  33 --- a/drivers/usb/typec/altmodes/displayport.c
  34 +++ b/drivers/usb/typec/altmodes/displayport.c
  35 @@ -527,15 +527,20 @@ static ssize_t pin_assignment_show(struc
  36  }
  37  static DEVICE_ATTR_RW(pin_assignment);
  38
  39 -static struct attribute *dp_altmode_attrs[] = {
  40 +static struct attribute *displayport_attrs[] = {
  41         &dev_attr_configuration.attr,
  42         &dev_attr_pin_assignment.attr,
  43         NULL
  44  };
  45
  46 -static const struct attribute_group dp_altmode_group = {
  47 +static const struct attribute_group displayport_group = {
  48         .name = "displayport",
  49 -       .attrs = dp_altmode_attrs,
  50 +       .attrs = displayport_attrs,
  51 +};
  52 +
  53 +static const struct attribute_group *displayport_groups[] = {
  54 +       &displayport_group,
  55 +       NULL,
  56  };
  57
  58  int dp_altmode_probe(struct typec_altmode *alt)
  59 @@ -543,7 +548,6 @@ int dp_altmode_probe(struct typec_altmod
  60         const struct typec_altmode *port = typec_altmode_get_partner(alt);
  61         struct fwnode_handle *fwnode;
  62         struct dp_altmode *dp;
  63 -       int ret;
  64
  65         /* FIXME: Port can only be DFP_U. */
  66
  67 @@ -554,10 +558,6 @@ int dp_altmode_probe(struct typec_altmod
  68               DP_CAP_PIN_ASSIGN_DFP_D(alt->vdo)))
  69                 return -ENODEV;
  70
  71 -       ret = sysfs_create_group(&alt->dev.kobj, &dp_altmode_group);
  72 -       if (ret)
  73 -               return ret;
  74 -
  75         dp = devm_kzalloc(&alt->dev, sizeof(*dp), GFP_KERNEL);
  76         if (!dp)
  77                 return -ENOMEM;
  78 @@ -588,7 +588,6 @@ void dp_altmode_remove(struct typec_altm
  79  {
  80         struct dp_altmode *dp = typec_altmode_get_drvdata(alt);
  81
  82 -       sysfs_remove_group(&alt->dev.kobj, &dp_altmode_group);
  83         cancel_work_sync(&dp->work);
  84
  85         if (dp->connector_fwnode) {
  86 @@ -613,6 +612,7 @@ static struct typec_altmode_driver dp_al
  87         .driver = {
  88                 .name = "typec_displayport",
  89                 .owner = THIS_MODULE,
  90 +               .dev_groups = displayport_groups,
  91         },
  92  };
  93  module_typec_altmode_driver(dp_altmode_driver);