All of lore.kernel.org
 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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.