From: "Winkler, Tomas" <tomas.wink...@intel.com>
Utilize runtime_pm for driving tpm crb idle states.
The framework calls cmd_ready from the pm_runtime_resume handler
and go idle from the pm_runtime_suspend handler.
The TPM framework should wake the device before transmit and receive.
In case the runtime_pm framework is not compiled in or enabled, the device
will be in the permanent ready state.
Signed-off-by: Tomas Winkler <tomas.wink...@intel.com>
---
V2: new in the series
V3: resend
V4: fix unbalanced runtime pm put and get
drivers/char/tpm/tpm-interface.c | 5 +++++
drivers/char/tpm/tpm_crb.c | 42 ++++++++++++++++++++++++++++++++++++----
2 files changed, 43 insertions(+), 4 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 8de61876f633..7743e8a21b82 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -29,6 +29,7 @@
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>
+#include <linux/pm_runtime.h>
#include "tpm.h"
#include "tpm_eventlog.h"
@@ -356,6 +357,8 @@ ssize_t tpm_transmit(struct tpm_chip *chip, const u8 *buf,
size_t bufsiz,
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_lock(&chip->tpm_mutex);
+ pm_runtime_get_sync(chip->dev.parent);
+
rc = chip->ops->send(chip, (u8 *) buf, count);
if (rc < 0) {
dev_err(&chip->dev,
@@ -397,6 +400,8 @@ out_recv:
dev_err(&chip->dev,
"tpm_transmit: tpm_recv: error %zd\n", rc);
out:
+ pm_runtime_put_sync(chip->dev.parent);
+
if (!(flags & TPM_TRANSMIT_UNLOCKED))
mutex_unlock(&chip->tpm_mutex);
return rc;
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index def50b7d47b2..eccd82af6215 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -19,6 +19,7 @@
#include <linux/highmem.h>
#include <linux/rculist.h>
#include <linux/module.h>
+#include <linux/pm_runtime.h>
#include "tpm.h"
#define ACPI_SIG_TPM2 "TPM2"
@@ -153,8 +154,6 @@ static int __maybe_unused crb_cmd_ready(struct device *dev,
return 0;
}
-static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume);
-
static u8 crb_status(struct tpm_chip *chip)
{
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
@@ -437,11 +436,21 @@ static int crb_acpi_add(struct acpi_device *device)
if (rc)
return rc;
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
rc = tpm_chip_register(chip);
- if (rc)
+ if (rc) {
crb_go_idle(dev, priv);
+ pm_runtime_put_noidle(dev);
+ pm_runtime_disable(dev);
+ return rc;
+ }
- return rc;
+ pm_runtime_put(dev);
+
+ return 0;
}
static int crb_acpi_remove(struct acpi_device *device)
@@ -451,9 +460,34 @@ static int crb_acpi_remove(struct acpi_device *device)
tpm_chip_unregister(chip);
+ pm_runtime_disable(dev);
+
return 0;
}
+#ifdef CONFIG_PM
+static int crb_pm_runtime_suspend(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+
+ return crb_go_idle(dev, priv);
+}
+
+static int crb_pm_runtime_resume(struct device *dev)
+{
+ struct tpm_chip *chip = dev_get_drvdata(dev);
+ struct crb_priv *priv = dev_get_drvdata(&chip->dev);
+
+ return crb_cmd_ready(dev, priv);
+}
+#endif /* CONFIG_PM */
+
+static const struct dev_pm_ops crb_pm = {
+ SET_SYSTEM_SLEEP_PM_OPS(tpm_pm_suspend, tpm_pm_resume)
+ SET_RUNTIME_PM_OPS(crb_pm_runtime_suspend, crb_pm_runtime_resume, NULL)
+};
+
static struct acpi_device_id crb_device_ids[] = {
{"MSFT0101", 0},
{"", 0},
--
2.7.4
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