In case of SPI wiring issues (e.g. MISO pin permanent high) the core init won't provide any error message on failure. Add some helpful error messages to tpm_tis_core_init(), which helps to better understand why the driver won't probe.
Signed-off-by: Stefan Wahren <[email protected]> --- drivers/char/tpm/tpm_tis_core.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index fdef214b9f6b..830e331fcebe 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -1133,8 +1133,10 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, dev_set_drvdata(&chip->dev, priv); rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor); - if (rc < 0) + if (rc < 0) { + dev_err(dev, "Failed to read TPM_DID_VID register: %d\n", rc); return rc; + } priv->manufacturer_id = vendor; @@ -1162,19 +1164,25 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, chip->ops->clk_enable(chip, true); if (wait_startup(chip, 0) != 0) { + dev_err(dev, "TPM device not accessible (0x%0x)\n", + vendor); rc = -ENODEV; goto out_err; } /* Take control of the TPM's interrupt hardware and shut it off */ rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask); - if (rc < 0) + if (rc < 0) { + dev_err(dev, "Failed to read TPM_INT_ENABLE register: %d\n", rc); goto out_err; + } /* Figure out the capabilities */ rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps); - if (rc < 0) + if (rc < 0) { + dev_err(dev, "Failed to read TPM_INTF_CAPS register: %d\n", rc); goto out_err; + } dev_dbg(dev, "TPM interface capabilities (0x%x):\n", intfcaps); @@ -1209,6 +1217,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq, rc = tpm_tis_request_locality(chip, 0); if (rc < 0) { + dev_err(dev, "Failed to request locality (0x%0x)\n", vendor); rc = -ENODEV; goto out_err; } -- 2.34.1
