tpm: add support for nonblocking operation

Currently the TPM driver only supports blocking calls, which doesn't allow
asynchronous IO operations to the TPM hardware.
This patch changes it and adds support for nonblocking write and a new poll
function to enable applications, which want to take advantage of this.

Tested-by: Philip Tricca <philip.b.tricca@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off--by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

1 files changed, 19 insertions, 5 deletions

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 7d958ff426e0..129f640424b7 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -1409,19 +1409,32 @@ static int __init tpm_init(void)
 	tpmrm_class = class_create(THIS_MODULE, "tpmrm");
 	if (IS_ERR(tpmrm_class)) {
 		pr_err("couldn't create tpmrm class\n");
-		class_destroy(tpm_class);
-		return PTR_ERR(tpmrm_class);
+		rc = PTR_ERR(tpmrm_class);
+		goto out_destroy_tpm_class;
 	}
 
 	rc = alloc_chrdev_region(&tpm_devt, 0, 2*TPM_NUM_DEVICES, "tpm");
 	if (rc < 0) {
 		pr_err("tpm: failed to allocate char dev region\n");
-		class_destroy(tpmrm_class);
-		class_destroy(tpm_class);
-		return rc;
+		goto out_destroy_tpmrm_class;
+	}
+
+	rc = tpm_dev_common_init();
+	if (rc) {
+		pr_err("tpm: failed to allocate char dev region\n");
+		goto out_unreg_chrdev;
 	}
 
 	return 0;
+
+out_unreg_chrdev:
+	unregister_chrdev_region(tpm_devt, 2 * TPM_NUM_DEVICES);
+out_destroy_tpmrm_class:
+	class_destroy(tpmrm_class);
+out_destroy_tpm_class:
+	class_destroy(tpm_class);
+
+	return rc;
 }
 
 static void __exit tpm_exit(void)
@@ -1430,6 +1443,7 @@ static void __exit tpm_exit(void)
 	class_destroy(tpm_class);
 	class_destroy(tpmrm_class);
 	unregister_chrdev_region(tpm_devt, 2*TPM_NUM_DEVICES);
+	tpm_dev_common_exit();
 }
 
 subsys_initcall(tpm_init);