linux-pci.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Rajat Jain <rajatxjain@gmail.com>
To: Bjorn Helgaas <bhelgaas@google.com>,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Rajat Jain <rajatjain@juniper.net>,
	Guenter Roeck <groeck@juniper.net>,
	Alex Williamson <alex.williamson@redhat.com>
Subject: [PATCH] pciehp: Remove a non-existent card, regardless of "surprise" capability
Date: Tue, 18 Feb 2014 18:53:19 -0800	[thread overview]
Message-ID: <53041C9F.7050801@gmail.com> (raw)

In case a card is physically yanked out, it should immediately be
removed, regardless of the "surprise" capability bit. Thus:

* Always handle the physical removal - regardless of the "surprise" bit.
* Don't use "surprise" capability when making decisions about enabling
presence detect notifications.
* Reword the comments to indicate the intent.

Signed-off-by: Rajat Jain <rajatxjain@gmail.com>
Signed-off-by: Rajat Jain <rajatjain@juniper.net>
Signed-off-by: Guenter Roeck <groeck@juniper.net>
---
 drivers/pci/hotplug/pciehp_ctrl.c |    9 ++++++++-
 drivers/pci/hotplug/pciehp_hpc.c  |    9 +++++----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index e027e36..c75e6a6 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -534,9 +534,16 @@ static void interrupt_event_handler(struct work_struct *work)
 		pciehp_green_led_off(p_slot);
 		break;
 	case INT_PRESENCE_ON:
-	case INT_PRESENCE_OFF:
 		if (!HP_SUPR_RM(ctrl))
 			break;
+		ctrl_dbg(ctrl, "Surprise Insertion\n");
+		handle_surprise_event(p_slot);
+		break;
+	case INT_PRESENCE_OFF:
+		/*
+		 * Regardless of surprise capability, we need to
+		 * definitely remove a card that has been pulled out!
+		 */
 		ctrl_dbg(ctrl, "Surprise Removal\n");
 		handle_surprise_event(p_slot);
 		break;
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index da4b020..d7d058f 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -619,9 +619,10 @@ static void pcie_disable_notification(struct controller *ctrl)
 
 /*
  * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
- * bus reset of the bridge, but if the slot supports surprise removal (or
- * link state change based hotplug), we need to disable presence detection
- * (or link state notifications) around the bus reset and clear any spurious
+ * bus reset of the bridge, but at the same time we want to ensure that it is
+ * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
+ * disable link state notification and presence detection change notification
+ * momentarily, if we see that they could interfere. Also, clear any spurious
  * events after.
  */
 int pciehp_reset_slot(struct slot *slot, int probe)
@@ -633,7 +634,7 @@ int pciehp_reset_slot(struct slot *slot, int probe)
 	if (probe)
 		return 0;
 
-	if (HP_SUPR_RM(ctrl) && !ATTN_BUTTN(ctrl)) {
+	if (!ATTN_BUTTN(ctrl)) {
 		ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
 		stat_mask |= PCI_EXP_SLTSTA_PDC;
 	}
-- 
1.7.9.5


             reply	other threads:[~2014-02-19  2:53 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-02-19  2:53 Rajat Jain [this message]
2014-02-19 22:07 ` [PATCH] pciehp: Remove a non-existent card, regardless of "surprise" capability Bjorn Helgaas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=53041C9F.7050801@gmail.com \
    --to=rajatxjain@gmail.com \
    --cc=alex.williamson@redhat.com \
    --cc=bhelgaas@google.com \
    --cc=groeck@juniper.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=rajatjain@juniper.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).