From: Jim Quinlan <jim2101024@gmail.com>
To: linux-pci@vger.kernel.org,
Nicolas Saenz Julienne <nsaenzjulienne@suse.de>,
Rob Herring <robh@kernel.org>, Mark Brown <broonie@kernel.org>,
bcm-kernel-feedback-list@broadcom.com, jim2101024@gmail.com,
james.quinlan@broadcom.com
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
Bjorn Helgaas <bhelgaas@google.com>,
Florian Fainelli <f.fainelli@gmail.com>,
linux-rpi-kernel@lists.infradead.org (moderated list:BROADCOM
BCM2711/BCM2835 ARM ARCHITECTURE),
linux-arm-kernel@lists.infradead.org (moderated list:BROADCOM
BCM2711/BCM2835 ARM ARCHITECTURE),
linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v4 4/6] PCI: brcmstb: Do not turn off regulators if EP can wake up
Date: Thu, 1 Apr 2021 17:21:44 -0400 [thread overview]
Message-ID: <20210401212148.47033-5-jim2101024@gmail.com> (raw)
In-Reply-To: <20210401212148.47033-1-jim2101024@gmail.com>
If any downstream device may wake up during S2/S3 suspend, we do not want
to turn off its power when suspending.
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
---
drivers/pci/controller/pcie-brcmstb.c | 58 +++++++++++++++++++++++----
1 file changed, 51 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index 1b0de0c7da60..4c79aff66de7 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -193,6 +193,7 @@ static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie,
static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_perst_set_generic(struct brcm_pcie *pcie, u32 val);
+static bool brcm_pcie_link_up(struct brcm_pcie *pcie);
static const char * const supplies[] = {
"vpcie12v-supply",
@@ -304,22 +305,65 @@ struct brcm_pcie {
void (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
struct regulator_bulk_data supplies[PCIE_BRCM_MAX_EP_REGULATORS];
unsigned int num_supplies;
+ bool ep_wakeup_capable;
};
-static int brcm_set_regulators(struct brcm_pcie *pcie, bool on)
+static int pci_dev_may_wakeup(struct pci_dev *dev, void *data)
{
+ bool *ret = data;
+
+ if (device_may_wakeup(&dev->dev)) {
+ *ret = true;
+ dev_dbg(&dev->dev, "disable cancelled for wake-up device\n");
+ }
+ return (int) *ret;
+}
+
+enum {
+ TURN_OFF, /* Turn regulators off, unless an EP is wakeup-capable */
+ TURN_OFF_ALWAYS, /* Turn regulators off, no exceptions */
+ TURN_ON, /* Turn regulators on, unless pcie->ep_wakeup_capable */
+};
+
+static int brcm_set_regulators(struct brcm_pcie *pcie, int how)
+{
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
struct device *dev = pcie->dev;
int ret;
if (!pcie->num_supplies)
return 0;
- if (on)
+ if (how == TURN_ON) {
+ if (pcie->ep_wakeup_capable) {
+ /*
+ * We are resuming from a suspend. In the
+ * previous suspend we did not disable the power
+ * supplies, so there is no need to enable them
+ * (and falsely increase their usage count).
+ */
+ pcie->ep_wakeup_capable = false;
+ return 0;
+ }
+ } else if (how == TURN_OFF) {
+ /*
+ * If at least one device on this bus is enabled as a
+ * wake-up source, do not turn off regulators.
+ */
+ pcie->ep_wakeup_capable = false;
+ if (bridge->bus && brcm_pcie_link_up(pcie)) {
+ pci_walk_bus(bridge->bus, pci_dev_may_wakeup, &pcie->ep_wakeup_capable);
+ if (pcie->ep_wakeup_capable)
+ return 0;
+ }
+ }
+
+ if (how == TURN_ON)
ret = regulator_bulk_enable(pcie->num_supplies, pcie->supplies);
else
ret = regulator_bulk_disable(pcie->num_supplies, pcie->supplies);
if (ret)
dev_err(dev, "failed to %s EP regulators\n",
- on ? "enable" : "disable");
+ how == TURN_ON ? "enable" : "disable");
return ret;
}
@@ -1206,7 +1250,7 @@ static int brcm_pcie_suspend(struct device *dev)
brcm_phy_stop(pcie);
clk_disable_unprepare(pcie->clk);
- return brcm_set_regulators(pcie, false);
+ return brcm_set_regulators(pcie, TURN_OFF);
}
static int brcm_pcie_resume(struct device *dev)
@@ -1221,7 +1265,7 @@ static int brcm_pcie_resume(struct device *dev)
if (ret)
return ret;
- ret = brcm_set_regulators(pcie, true);
+ ret = brcm_set_regulators(pcie, TURN_ON);
if (ret)
return ret;
@@ -1261,7 +1305,7 @@ static void __brcm_pcie_remove(struct brcm_pcie *pcie)
brcm_phy_stop(pcie);
reset_control_assert(pcie->rescal);
clk_disable_unprepare(pcie->clk);
- brcm_set_regulators(pcie, false);
+ brcm_set_regulators(pcie, TURN_OFF_ALWAYS);
}
static int brcm_pcie_remove(struct platform_device *pdev)
@@ -1360,7 +1404,7 @@ static int brcm_pcie_probe(struct platform_device *pdev)
goto fail;
}
- ret = brcm_set_regulators(pcie, true);
+ ret = brcm_set_regulators(pcie, TURN_ON);
if (ret)
goto fail;
--
2.17.1
next prev parent reply other threads:[~2021-04-01 21:22 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-01 21:21 [PATCH v4 0/6] PCI: brcmstb: add slot0 device regulators and panic handler Jim Quinlan
2021-04-01 21:21 ` [PATCH v4 1/6] PCI: brcmstb: Check return value of clk_prepare_enable() Jim Quinlan
2021-04-01 21:21 ` [PATCH v4 2/6] dt-bindings: PCI: Add bindings for Brcmstb endpoint device voltage regulators Jim Quinlan
2021-04-06 16:47 ` Mark Brown
2021-04-06 17:26 ` Jim Quinlan
2021-04-06 17:32 ` Mark Brown
2021-04-06 18:25 ` Jim Quinlan
2021-04-07 11:27 ` Mark Brown
2021-04-07 18:35 ` Florian Fainelli
2021-04-07 20:07 ` Mark Brown
2021-04-08 16:20 ` Rob Herring
2021-04-08 16:33 ` Mark Brown
2021-04-08 16:58 ` Jim Quinlan
2021-04-08 17:55 ` Rob Herring
2021-04-08 17:41 ` Rob Herring
2021-04-01 21:21 ` [PATCH v4 3/6] PCI: brcmstb: Add control of slot0 " Jim Quinlan
2021-04-06 16:34 ` Mark Brown
2021-04-06 16:59 ` Jim Quinlan
2021-04-06 17:23 ` Mark Brown
2021-04-06 17:29 ` Jim Quinlan
2021-04-01 21:21 ` Jim Quinlan [this message]
2021-04-01 21:21 ` [PATCH v4 5/6] PCI: brcmstb: Give 7216 SOCs their own config type Jim Quinlan
2021-04-01 21:21 ` [PATCH v4 6/6] PCI: brcmstb: Add panic/die handler to RC driver Jim Quinlan
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=20210401212148.47033-5-jim2101024@gmail.com \
--to=jim2101024@gmail.com \
--cc=bcm-kernel-feedback-list@broadcom.com \
--cc=bhelgaas@google.com \
--cc=broonie@kernel.org \
--cc=f.fainelli@gmail.com \
--cc=james.quinlan@broadcom.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=linux-rpi-kernel@lists.infradead.org \
--cc=lorenzo.pieralisi@arm.com \
--cc=nsaenzjulienne@suse.de \
--cc=robh@kernel.org \
/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).