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authorChristophe RICARD <christophe.ricard@gmail.com>2016-02-23 22:25:49 +0100
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>2016-06-25 17:26:35 +0300
commit86ff205b8e7b5b85ef1eb5e13f92f37c40a7181a (patch)
treec3dab30435d95bda5aa31292a52a5eed9ca05f36 /drivers/char/tpm/st33zp24
parent22eb90db936755e5d600a4561a0cc7a82c791eb9 (diff)
tpm: st33zp24: Add support for acpi probing for spi device.
Add support for acpi probing. SMO3324 is used for st33zp24. It has been tested with the following acpi node on Minnowboard: Device (TPM1) { Name (_ADR, Zero) // _ADR: Address Name (_HID, "SMO3324") // _HID: Hardware ID Name (_CID, "SMO3324") // _CID: Compatible ID Name (_DDN, "SMO TPM") // _DDN: DOS Device Name Name (_UID, One) // _UID: Unique ID Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings { Name (SBUF, ResourceTemplate () { SpiSerialBus (0, PolarityLow, FourWireMode, 8, ControllerInitiated, 4000000, ClockPolarityLow, ClockPhaseFirst, "\\_SB.SPI1", 0x00, ResourceConsumer, ,) GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone, 0x0000, "\\_SB.GPO2", 0x00, ResourceConsumer, ,) { // Pin list 0x0001 } GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly, "\\_SB.GPO2", 0x00, ResourceConsumer, ,) { // Pin list 0x0002, } }) Return (SBUF) /* \_SB_.SPI1.TPM1._CRS.SBUF */ } Method (_STA, 0, NotSerialized) // _STA: Status { Return (0x0F) } } Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Diffstat (limited to 'drivers/char/tpm/st33zp24')
-rw-r--r--drivers/char/tpm/st33zp24/spi.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/drivers/char/tpm/st33zp24/spi.c b/drivers/char/tpm/st33zp24/spi.c
index eb351ba48689..173db725b535 100644
--- a/drivers/char/tpm/st33zp24/spi.c
+++ b/drivers/char/tpm/st33zp24/spi.c
@@ -19,8 +19,10 @@
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
+#include <linux/acpi.h>
#include <linux/tpm.h>
#include <linux/platform_data/st33zp24.h>
@@ -227,6 +229,42 @@ static const struct st33zp24_phy_ops spi_phy_ops = {
.recv = st33zp24_spi_recv,
};
+static int st33zp24_spi_acpi_request_resources(struct st33zp24_spi_phy *phy)
+{
+ struct spi_device *spi_dev = phy->spi_device;
+ const struct acpi_device_id *id;
+ struct gpio_desc *gpiod_lpcpd;
+ struct device *dev;
+
+ if (!spi_dev)
+ return -EINVAL;
+
+ dev = &spi_dev->dev;
+
+ /* Match the struct device against a given list of ACPI IDs */
+ id = acpi_match_device(dev->driver->acpi_match_table, dev);
+ if (!id)
+ return -ENODEV;
+
+ /* Get LPCPD GPIO from ACPI */
+ gpiod_lpcpd = devm_gpiod_get_index(dev, "TPM IO LPCPD", 1,
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(gpiod_lpcpd)) {
+ dev_err(dev, "Failed to retrieve lpcpd-gpios from acpi.\n");
+ phy->io_lpcpd = -1;
+ /*
+ * lpcpd pin is not specified. This is not an issue as
+ * power management can be also managed by TPM specific
+ * commands. So leave with a success status code.
+ */
+ return 0;
+ }
+
+ phy->io_lpcpd = desc_to_gpio(gpiod_lpcpd);
+
+ return 0;
+}
+
static int st33zp24_spi_of_request_resources(struct st33zp24_spi_phy *phy)
{
struct device_node *pp;
@@ -328,6 +366,10 @@ static int st33zp24_spi_probe(struct spi_device *dev)
ret = st33zp24_spi_request_resources(dev, phy);
if (ret)
return ret;
+ } else if (ACPI_HANDLE(&dev->dev)) {
+ ret = st33zp24_spi_acpi_request_resources(phy);
+ if (ret)
+ return ret;
}
phy->latency = st33zp24_spi_evaluate_latency(phy);
@@ -362,6 +404,12 @@ static const struct of_device_id of_st33zp24_spi_match[] = {
};
MODULE_DEVICE_TABLE(of, of_st33zp24_spi_match);
+static const struct acpi_device_id st33zp24_spi_acpi_match[] = {
+ {"SMO3324"},
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, st33zp24_spi_acpi_match);
+
static SIMPLE_DEV_PM_OPS(st33zp24_spi_ops, st33zp24_pm_suspend,
st33zp24_pm_resume);
@@ -370,6 +418,7 @@ static struct spi_driver st33zp24_spi_driver = {
.name = TPM_ST33_SPI,
.pm = &st33zp24_spi_ops,
.of_match_table = of_match_ptr(of_st33zp24_spi_match),
+ .acpi_match_table = ACPI_PTR(st33zp24_spi_acpi_match),
},
.probe = st33zp24_spi_probe,
.remove = st33zp24_spi_remove,