[PATCH 2/2] platform/x86: ISST: Use only TPMI interface when present

[Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>]

When the TPMI interface is present, use this interface instead of legacy.
On some systems legacy IO device is also present. Using both interfaces
together is confusing and may set the hardware in inconsistent state.

When TPMI interface is present, don't load legacy drivers.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com
---
 drivers/platform/x86/intel/speed_select_if/isst_if_common.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
index f886f9369fad..6283af37e73b 100644
--- a/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
+++ b/drivers/platform/x86/intel/speed_select_if/isst_if_common.c
@@ -775,6 +775,9 @@ int isst_if_cdev_register(int device_type, struct isst_if_cmd_cb *cb)
 	if (device_type >= ISST_IF_DEV_MAX)
 		return -EINVAL;
 
+	if (device_type < ISST_IF_DEV_TPMI && isst_hpm_support)
+		return -ENODEV;
+
 	mutex_lock(&punit_misc_dev_open_lock);
 	/* Device is already open, we don't want to add new callbacks */
 	if (misc_device_open) {
-- 
2.44.0