[PATCH 2/2] tpm: support driver-specific sysfs attrs in tpm_tis_core

[Andrey Pronin <apronin@chromium.org>]

Add attr_group to phy_ops that a driver relying on tpm_tis_core_init
can set to have its specific attributes registered in sysfs.

Signed-off-by: Andrey Pronin <apronin@chromium.org>
---
 drivers/char/tpm/tpm-sysfs.c    | 1 -
 drivers/char/tpm/tpm.h          | 8 +++++++-
 drivers/char/tpm/tpm_tis_core.c | 3 +++
 drivers/char/tpm/tpm_tis_core.h | 1 +
 4 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index 95ce90d..22c9874 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -304,7 +304,6 @@ void tpm_sysfs_add_device(struct tpm_chip *chip)
 	 * is called before ops is null'd and the sysfs core synchronizes this
 	 * removal so that no callbacks are running or can run again
 	 */
-	WARN_ON(chip->groups_cnt != 0);
 	chip->groups[chip->groups_cnt++] = &tpm_dev_group;
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		chip->groups[chip->groups_cnt++] = &tpm2_dev_group;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 8890df2..8c69649 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -173,7 +173,13 @@ struct tpm_chip {
 
 	struct dentry **bios_dir;
 
-	const struct attribute_group *groups[3];
+	/* up to 4 attribute groups:
+	 * - driver-specific
+	 * - common TPM1.2 and TPM2.0
+	 * - TPM1.2/2.0-specific
+	 * - ppi
+	 */
+	const struct attribute_group *groups[5];
 	unsigned int groups_cnt;
 #ifdef CONFIG_ACPI
 	acpi_handle acpi_dev_handle;
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index 8110b52..6d5d8f4 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -796,6 +796,9 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		}
 	}
 
+	if (priv->phy_ops->attr_group)
+		chip->groups[chip->groups_cnt++] = priv->phy_ops->attr_group;
+
 	return tpm_chip_register(chip);
 out_err:
 	tpm_tis_remove(chip);
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 9191aab..4417ed9 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -95,6 +95,7 @@ struct tpm_tis_data {
 };
 
 struct tpm_tis_phy_ops {
+	const struct attribute_group *attr_group;
 	int (*read_bytes)(struct tpm_tis_data *data, u32 addr, u16 len,
 			  u8 *result);
 	int (*write_bytes)(struct tpm_tis_data *data, u32 addr, u16 len,
-- 
2.6.6