Am 1. März 2017 12:51:16 MEZ schrieb Enric Balletbo i Serra <enric.balle...@collabora.com>: >From: Sonny Rao <sonny...@chromium.org> > >The suspend/resume behavior of the TPM can be controlled >by setting "powered-while-suspended" in the DTS. > >Signed-off-by: Sonny Rao <sonny...@chromium.org> >Signed-off-by: Enric Balletbo i Serra <enric.balle...@collabora.com> >--- >Documentation/devicetree/bindings/tpm/tpm.txt | 25 >+++++++++++++++++++++++++ >drivers/char/tpm/tpm_i2c_infineon.c | 25 >++++++++++++++++++++++++- > 2 files changed, 49 insertions(+), 1 deletion(-) > create mode 100644 Documentation/devicetree/bindings/tpm/tpm.txt > >diff --git a/Documentation/devicetree/bindings/tpm/tpm.txt >b/Documentation/devicetree/bindings/tpm/tpm.txt >new file mode 100644 >index 0000000..af4de0d >--- /dev/null >+++ b/Documentation/devicetree/bindings/tpm/tpm.txt
Hi, for this device there exists a binding in the i2c subfolder https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/i2c/trivial-devices.txt?id=refs/tags/v4.10 Peter >@@ -0,0 +1,25 @@ >+TPM (Trusted Platform Module) >+ >+A TPM on the I2C bus is a child of the node for the bus. >+ >+Required properties: >+- compatible: should be "infineon,<chip>" >+- reg: the I2C address >+ >+Optional properties: >+- powered-while-suspended: present when the TPM is left powered on >between >+ suspend and resume (makes the suspend/resume callbacks do nothing). >+ >+Example: >+ i2c@12C90000 { >+ samsung,i2c-sda-delay = <100>; >+ samsung,i2c-max-bus-freq = <66000>; >+ gpios = <&gpa1 2 3 3 0>, >+ <&gpa1 3 3 3 0>; >+ >+ tpm { >+ compatible = "infineon,slb9635tt"; >+ reg = <0x20>; >+ powered-while-suspended; >+ }; >+ }; >diff --git a/drivers/char/tpm/tpm_i2c_infineon.c >b/drivers/char/tpm/tpm_i2c_infineon.c >index 62ee44e..19d9522 100644 >--- a/drivers/char/tpm/tpm_i2c_infineon.c >+++ b/drivers/char/tpm/tpm_i2c_infineon.c >@@ -70,6 +70,7 @@ struct tpm_inf_dev { > u8 buf[TPM_BUFSIZE + sizeof(u8)]; /* max. buffer size + addr */ > struct tpm_chip *chip; > enum i2c_chip_type chip_type; >+ bool powered_while_suspended; > }; > > static struct tpm_inf_dev tpm_dev; >@@ -599,6 +600,11 @@ static int tpm_tis_i2c_init(struct device *dev) > goto out_err; > } > >+ if (dev->of_node && >+ of_get_property(dev->of_node, "powered-while-suspended", NULL)) { >+ tpm_dev.powered_while_suspended = true; >+ } >+ > /* read four bytes from DID_VID register */ > if (iic_tpm_read(TPM_DID_VID(0), (u8 *)&vendor, 4) < 0) { > dev_err(dev, "could not read vendor id\n"); >@@ -662,7 +668,24 @@ static const struct of_device_id >tpm_tis_i2c_of_match[] = { > MODULE_DEVICE_TABLE(of, tpm_tis_i2c_of_match); > #endif > >-static SIMPLE_DEV_PM_OPS(tpm_tis_i2c_ops, tpm_pm_suspend, >tpm_pm_resume); >+static int __maybe_unused tpm_tis_i2c_suspend(struct device *dev) >+{ >+ if (tpm_dev.powered_while_suspended) >+ return 0; >+ >+ return tpm_pm_suspend(dev); >+} >+ >+static int __maybe_unused tpm_tis_i2c_resume(struct device *dev) >+{ >+ if (tpm_dev.powered_while_suspended) >+ return 0; >+ >+ return tpm_pm_resume(dev); >+} >+ >+static SIMPLE_DEV_PM_OPS(tpm_tis_i2c_ops, tpm_tis_i2c_suspend, >+ tpm_tis_i2c_resume); > > static int tpm_tis_i2c_probe(struct i2c_client *client, > const struct i2c_device_id *id) -- Sent from my mobile
