[PATCH v2] tpm: Fix the ioremap() call for Braswell systems

From: Azhar Shaikh
Date: Thu Jun 22 2017 - 17:32:11 EST


ioremap() for Intel Braswell processors was done in
tpm_tis_pnp_init(). But before this function gets called,
platform driver 'tis_drv' gets registered and its probe function
tpm_tis_plat_probe() is invoked, which does a TPM
access. Now for Braswell processors tpm_platform_begin_xfer()
will do an ioread32() without having a mapped address, which
will lead to a bad I/O access warning.
Hence move the ioremap() call from tpm_tis_pnp_init() to init_tis()
before registering the 'tis_drv' or basically before any TPM access.
Accordingly also move the iounmap() call from tpm_tis_pnp_remove()
to cleanup_tis() after all TPM access are completed.

Signed-off-by: Azhar Shaikh <azhar.shaikh@xxxxxxxxx>
---
Changes from v1:
- Do error handling in init_ts().
- Update the commit message.

drivers/char/tpm/tpm_tis.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 506e62ca3576..d97ce22267fb 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -330,12 +330,6 @@ static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
else
tpm_info.irq = -1;

-#ifdef CONFIG_X86
- if (is_bsw())
- ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
- ILB_REMAP_SIZE);
-#endif
-
return tpm_tis_init(&pnp_dev->dev, &tpm_info);
}

@@ -359,12 +353,6 @@ static void tpm_tis_pnp_remove(struct pnp_dev *dev)

tpm_chip_unregister(chip);
tpm_tis_remove(chip);
-
-#ifdef CONFIG_X86
- if (is_bsw())
- iounmap(ilb_base_addr);
-#endif
-
}

static struct pnp_driver tis_pnp_driver = {
@@ -472,6 +460,11 @@ static int __init init_tis(void)
if (rc)
goto err_force;

+#ifdef CONFIG_X86
+ if (is_bsw())
+ ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
+ ILB_REMAP_SIZE);
+#endif
rc = platform_driver_register(&tis_drv);
if (rc)
goto err_platform;
@@ -490,6 +483,10 @@ static int __init init_tis(void)
err_platform:
if (force_pdev)
platform_device_unregister(force_pdev);
+#ifdef CONFIG_X86
+ if (is_bsw())
+ iounmap(ilb_base_addr);
+#endif
err_force:
return rc;
}
@@ -499,6 +496,10 @@ static void __exit cleanup_tis(void)
pnp_unregister_driver(&tis_pnp_driver);
platform_driver_unregister(&tis_drv);

+#ifdef CONFIG_X86
+ if (is_bsw())
+ iounmap(ilb_base_addr);
+#endif
if (force_pdev)
platform_device_unregister(force_pdev);
}
--
1.9.1