diff mbox series

[14/33] iris: vidc: add helpers for state management

Message ID 1690550624-14642-15-git-send-email-quic_vgarodia@quicinc.com (mailing list archive)
State Not Applicable
Headers show
Series Qualcomm video decoder/encoder driver | expand

Commit Message

Vikash Garodia July 28, 2023, 1:23 p.m. UTC
This implements the functions to handle different core
and instance state transitions.

Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
Signed-off-by: Vikash Garodia <quic_vgarodia@quicinc.com>
---
 .../platform/qcom/iris/vidc/inc/msm_vidc_state.h   |  102 ++
 .../platform/qcom/iris/vidc/src/msm_vidc_state.c   | 1607 ++++++++++++++++++++
 2 files changed, 1709 insertions(+)
 create mode 100644 drivers/media/platform/qcom/iris/vidc/inc/msm_vidc_state.h
 create mode 100644 drivers/media/platform/qcom/iris/vidc/src/msm_vidc_state.c

Comments

Konrad Dybcio July 28, 2023, 5:52 p.m. UTC | #1
On 28.07.2023 15:23, Vikash Garodia wrote:
> This implements the functions to handle different core
> and instance state transitions.
> 
> Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
> Signed-off-by: Vikash Garodia <quic_vgarodia@quicinc.com>
> ---
[...]

> +enum msm_vidc_core_sub_state {
> +	CORE_SUBSTATE_NONE                   = 0x0,
> +	CORE_SUBSTATE_POWER_ENABLE           = BIT(0),
> +	CORE_SUBSTATE_GDSC_HANDOFF           = BIT(1),
> +	CORE_SUBSTATE_PM_SUSPEND             = BIT(2),
> +	CORE_SUBSTATE_FW_PWR_CTRL            = BIT(3),
> +	CORE_SUBSTATE_PAGE_FAULT             = BIT(4),
> +	CORE_SUBSTATE_CPU_WATCHDOG           = BIT(5),
> +	CORE_SUBSTATE_VIDEO_UNRESPONSIVE     = BIT(6),
> +	CORE_SUBSTATE_MAX                    = BIT(7),
Why store it in an enum if they're not consecutive? You can make them
preprocessor #defines.

> +};
> +
> +enum msm_vidc_core_event_type {
> +	CORE_EVENT_NONE                      = BIT(0),
> +	CORE_EVENT_UPDATE_SUB_STATE          = BIT(1),
> +};
Ditto (even though techinically they're consecutive)

> +
> +enum msm_vidc_state {
> +	MSM_VIDC_OPEN,
> +	MSM_VIDC_INPUT_STREAMING,
> +	MSM_VIDC_OUTPUT_STREAMING,
> +	MSM_VIDC_STREAMING,
> +	MSM_VIDC_CLOSE,
> +	MSM_VIDC_ERROR,
> +};
> +
> +#define MSM_VIDC_SUB_STATE_NONE          0
> +#define MSM_VIDC_MAX_SUB_STATES          6
> +/*
> + * max value of inst->sub_state if all
> + * the 6 valid bits are set i.e 111111==>63
> + */
> +#define MSM_VIDC_MAX_SUB_STATE_VALUE     ((1 << MSM_VIDC_MAX_SUB_STATES) - 1)
> +
> +enum msm_vidc_sub_state {
> +	MSM_VIDC_DRAIN                     = BIT(0),
> +	MSM_VIDC_DRC                       = BIT(1),
> +	MSM_VIDC_DRAIN_LAST_BUFFER         = BIT(2),
> +	MSM_VIDC_DRC_LAST_BUFFER           = BIT(3),
> +	MSM_VIDC_INPUT_PAUSE               = BIT(4),
> +	MSM_VIDC_OUTPUT_PAUSE              = BIT(5),
Ditto

[...]

> +static int msm_vidc_core_init_wait_state(struct msm_vidc_core *core,
> +					 enum msm_vidc_core_event_type type,
> +					 struct msm_vidc_event_data *data)
> +{
> +	int rc = 0;
rc seems never assigned again, good to drop

[...]

> +
> +static int msm_vidc_core_init_state(struct msm_vidc_core *core,
> +				    enum msm_vidc_core_event_type type,
> +				    struct msm_vidc_event_data *data)
> +{
> +	int rc = 0;
Ditto

[...]

> +static int msm_vidc_core_error_state(struct msm_vidc_core *core,
> +				     enum msm_vidc_core_event_type type,
> +				     struct msm_vidc_event_data *data)
> +{
> +	int rc = 0;
Ditto

[...]

> +int msm_vidc_update_core_state(struct msm_vidc_core *core,
> +			       enum msm_vidc_core_state request_state, const char *func)
> +{
> +	struct msm_vidc_core_state_handle *state_handle = NULL;
> +	int rc = 0;
Ditto

[...]

> +int msm_vidc_change_core_state(struct msm_vidc_core *core,
> +			       enum msm_vidc_core_state request_state, const char *func)
> +{
> +	enum msm_vidc_allow allow;
> +	int rc = 0;
Ditto

[...]

> +bool is_state(struct msm_vidc_inst *inst, enum msm_vidc_state state)
> +{
> +	return inst->state == state;
> +}
> +
> +bool is_sub_state(struct msm_vidc_inst *inst, enum msm_vidc_sub_state sub_state)
> +{
> +	return (inst->sub_state & sub_state);
> +}
Why are there 2 separate funcs for core and inst? Don't we have
a pointer within one to the other?


[...]

> +
> +int msm_vidc_update_state(struct msm_vidc_inst *inst,
> +			  enum msm_vidc_state request_state, const char *func)
> +{
> +	struct msm_vidc_state_handle *state_handle = NULL;
> +	int rc = 0;
rc is unused

[...]

> +static int msm_vidc_set_sub_state(struct msm_vidc_inst *inst,
> +				  enum msm_vidc_sub_state sub_state, const char *func)
> +{
> +	char sub_state_name[MAX_NAME_LENGTH];
> +	int cnt, rc = 0;
ditto

Konrad
Dikshita Agarwal Aug. 14, 2023, 7:17 p.m. UTC | #2
On 7/28/2023 11:22 PM, Konrad Dybcio wrote:
> On 28.07.2023 15:23, Vikash Garodia wrote:
>> This implements the functions to handle different core
>> and instance state transitions.
>>
>> Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
>> Signed-off-by: Vikash Garodia <quic_vgarodia@quicinc.com>
>> ---
> [...]
> 
>> +enum msm_vidc_core_sub_state {
>> +	CORE_SUBSTATE_NONE                   = 0x0,
>> +	CORE_SUBSTATE_POWER_ENABLE           = BIT(0),
>> +	CORE_SUBSTATE_GDSC_HANDOFF           = BIT(1),
>> +	CORE_SUBSTATE_PM_SUSPEND             = BIT(2),
>> +	CORE_SUBSTATE_FW_PWR_CTRL            = BIT(3),
>> +	CORE_SUBSTATE_PAGE_FAULT             = BIT(4),
>> +	CORE_SUBSTATE_CPU_WATCHDOG           = BIT(5),
>> +	CORE_SUBSTATE_VIDEO_UNRESPONSIVE     = BIT(6),
>> +	CORE_SUBSTATE_MAX                    = BIT(7),
> Why store it in an enum if they're not consecutive? You can make them
> preprocessor #defines.
> 
I understand that these are not consecutive but a enum for these makes them
under one roof which is easy to read and maintain, we will loose this if
replaced with macro.
>> +};
>> +
>> +enum msm_vidc_core_event_type {
>> +	CORE_EVENT_NONE                      = BIT(0),
>> +	CORE_EVENT_UPDATE_SUB_STATE          = BIT(1),
>> +};
> Ditto (even though techinically they're consecutive)
> 
>> +
>> +enum msm_vidc_state {
>> +	MSM_VIDC_OPEN,
>> +	MSM_VIDC_INPUT_STREAMING,
>> +	MSM_VIDC_OUTPUT_STREAMING,
>> +	MSM_VIDC_STREAMING,
>> +	MSM_VIDC_CLOSE,
>> +	MSM_VIDC_ERROR,
>> +};
>> +
>> +#define MSM_VIDC_SUB_STATE_NONE          0
>> +#define MSM_VIDC_MAX_SUB_STATES          6
>> +/*
>> + * max value of inst->sub_state if all
>> + * the 6 valid bits are set i.e 111111==>63
>> + */
>> +#define MSM_VIDC_MAX_SUB_STATE_VALUE     ((1 << MSM_VIDC_MAX_SUB_STATES) - 1)
>> +
>> +enum msm_vidc_sub_state {
>> +	MSM_VIDC_DRAIN                     = BIT(0),
>> +	MSM_VIDC_DRC                       = BIT(1),
>> +	MSM_VIDC_DRAIN_LAST_BUFFER         = BIT(2),
>> +	MSM_VIDC_DRC_LAST_BUFFER           = BIT(3),
>> +	MSM_VIDC_INPUT_PAUSE               = BIT(4),
>> +	MSM_VIDC_OUTPUT_PAUSE              = BIT(5),
> Ditto
> 
these are bit wise and are being used in state machine. At a time, two or
more bits can be set to define the state of and instance, hence needed.

> [...]
> 
>> +static int msm_vidc_core_init_wait_state(struct msm_vidc_core *core,
>> +					 enum msm_vidc_core_event_type type,
>> +					 struct msm_vidc_event_data *data)
>> +{
>> +	int rc = 0;
> rc seems never assigned again, good to drop
> 
> [...]
> 
Sure, will remove in next version
>> +
>> +static int msm_vidc_core_init_state(struct msm_vidc_core *core,
>> +				    enum msm_vidc_core_event_type type,
>> +				    struct msm_vidc_event_data *data)
>> +{
>> +	int rc = 0;
> Ditto
> 
> [...]
> 
>> +static int msm_vidc_core_error_state(struct msm_vidc_core *core,
>> +				     enum msm_vidc_core_event_type type,
>> +				     struct msm_vidc_event_data *data)
>> +{
>> +	int rc = 0;
> Ditto
> 
> [...]
> 
>> +int msm_vidc_update_core_state(struct msm_vidc_core *core,
>> +			       enum msm_vidc_core_state request_state, const char *func)
>> +{
>> +	struct msm_vidc_core_state_handle *state_handle = NULL;
>> +	int rc = 0;
> Ditto
> 
> [...]
> 
>> +int msm_vidc_change_core_state(struct msm_vidc_core *core,
>> +			       enum msm_vidc_core_state request_state, const char *func)
>> +{
>> +	enum msm_vidc_allow allow;
>> +	int rc = 0;
> Ditto
> 
will remove all such instances of unused rc in next version
> [...]
> 
>> +bool is_state(struct msm_vidc_inst *inst, enum msm_vidc_state state)
>> +{
>> +	return inst->state == state;
>> +}
>> +
>> +bool is_sub_state(struct msm_vidc_inst *inst, enum msm_vidc_sub_state sub_state)
>> +{
>> +	return (inst->sub_state & sub_state);
>> +}
> Why are there 2 separate funcs for core and inst? Don't we have
> a pointer within one to the other?
> 
> 
core and instance sub states are maintained differently for ex in SSR, we
need to check the core sub state, if we combine instance and core state
checks, we won't know against which sub state we should check.
> [...]
> 

>> +
>> +int msm_vidc_update_state(struct msm_vidc_inst *inst,
>> +			  enum msm_vidc_state request_state, const char *func)
>> +{
>> +	struct msm_vidc_state_handle *state_handle = NULL;
>> +	int rc = 0;
> rc is unused
> 
> [...]
> 
>> +static int msm_vidc_set_sub_state(struct msm_vidc_inst *inst,
>> +				  enum msm_vidc_sub_state sub_state, const char *func)
>> +{
>> +	char sub_state_name[MAX_NAME_LENGTH];
>> +	int cnt, rc = 0;
> ditto
> 
Thanks for pointing these out, will remove all unused rc.

Thanks,
Dikshita
> Konrad
diff mbox series

Patch

diff --git a/drivers/media/platform/qcom/iris/vidc/inc/msm_vidc_state.h b/drivers/media/platform/qcom/iris/vidc/inc/msm_vidc_state.h
new file mode 100644
index 0000000..7fe4fcc
--- /dev/null
+++ b/drivers/media/platform/qcom/iris/vidc/inc/msm_vidc_state.h
@@ -0,0 +1,102 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _MSM_VIDC_STATE_H_
+#define _MSM_VIDC_STATE_H_
+
+#include "msm_vidc_internal.h"
+
+enum msm_vidc_core_state {
+	MSM_VIDC_CORE_DEINIT,
+	MSM_VIDC_CORE_INIT_WAIT,
+	MSM_VIDC_CORE_INIT,
+	MSM_VIDC_CORE_ERROR,
+};
+
+enum msm_vidc_core_sub_state {
+	CORE_SUBSTATE_NONE                   = 0x0,
+	CORE_SUBSTATE_POWER_ENABLE           = BIT(0),
+	CORE_SUBSTATE_GDSC_HANDOFF           = BIT(1),
+	CORE_SUBSTATE_PM_SUSPEND             = BIT(2),
+	CORE_SUBSTATE_FW_PWR_CTRL            = BIT(3),
+	CORE_SUBSTATE_PAGE_FAULT             = BIT(4),
+	CORE_SUBSTATE_CPU_WATCHDOG           = BIT(5),
+	CORE_SUBSTATE_VIDEO_UNRESPONSIVE     = BIT(6),
+	CORE_SUBSTATE_MAX                    = BIT(7),
+};
+
+enum msm_vidc_core_event_type {
+	CORE_EVENT_NONE                      = BIT(0),
+	CORE_EVENT_UPDATE_SUB_STATE          = BIT(1),
+};
+
+enum msm_vidc_state {
+	MSM_VIDC_OPEN,
+	MSM_VIDC_INPUT_STREAMING,
+	MSM_VIDC_OUTPUT_STREAMING,
+	MSM_VIDC_STREAMING,
+	MSM_VIDC_CLOSE,
+	MSM_VIDC_ERROR,
+};
+
+#define MSM_VIDC_SUB_STATE_NONE          0
+#define MSM_VIDC_MAX_SUB_STATES          6
+/*
+ * max value of inst->sub_state if all
+ * the 6 valid bits are set i.e 111111==>63
+ */
+#define MSM_VIDC_MAX_SUB_STATE_VALUE     ((1 << MSM_VIDC_MAX_SUB_STATES) - 1)
+
+enum msm_vidc_sub_state {
+	MSM_VIDC_DRAIN                     = BIT(0),
+	MSM_VIDC_DRC                       = BIT(1),
+	MSM_VIDC_DRAIN_LAST_BUFFER         = BIT(2),
+	MSM_VIDC_DRC_LAST_BUFFER           = BIT(3),
+	MSM_VIDC_INPUT_PAUSE               = BIT(4),
+	MSM_VIDC_OUTPUT_PAUSE              = BIT(5),
+};
+
+enum msm_vidc_event {
+	MSM_VIDC_TRY_FMT,
+	MSM_VIDC_S_FMT,
+	MSM_VIDC_REQBUFS,
+	MSM_VIDC_S_CTRL,
+	MSM_VIDC_STREAMON,
+	MSM_VIDC_STREAMOFF,
+	MSM_VIDC_CMD_START,
+	MSM_VIDC_CMD_STOP,
+	MSM_VIDC_BUF_QUEUE,
+};
+
+/* core statemachine functions */
+enum msm_vidc_allow msm_vidc_allow_core_state_change(struct msm_vidc_core *core,
+						     enum msm_vidc_core_state req_state);
+int msm_vidc_update_core_state(struct msm_vidc_core *core,
+			       enum msm_vidc_core_state request_state, const char *func);
+bool core_in_valid_state(struct msm_vidc_core *core);
+bool is_core_state(struct msm_vidc_core *core, enum msm_vidc_core_state state);
+bool is_core_sub_state(struct msm_vidc_core *core, enum msm_vidc_core_sub_state sub_state);
+const char *core_state_name(enum msm_vidc_core_state state);
+const char *core_sub_state_name(enum msm_vidc_core_sub_state sub_state);
+
+/* inst statemachine functions */
+bool is_drc_pending(struct msm_vidc_inst *inst);
+bool is_drain_pending(struct msm_vidc_inst *inst);
+int msm_vidc_update_state(struct msm_vidc_inst *inst,
+			  enum msm_vidc_state request_state, const char *func);
+int msm_vidc_change_state(struct msm_vidc_inst *inst,
+			  enum msm_vidc_state request_state, const char *func);
+int msm_vidc_change_sub_state(struct msm_vidc_inst *inst,
+			      enum msm_vidc_sub_state clear_sub_state,
+			      enum msm_vidc_sub_state set_sub_state,
+			      const char *func);
+const char *state_name(enum msm_vidc_state state);
+const char *sub_state_name(enum msm_vidc_sub_state sub_state);
+bool is_state(struct msm_vidc_inst *inst, enum msm_vidc_state state);
+bool is_sub_state(struct msm_vidc_inst *inst,
+		  enum msm_vidc_sub_state sub_state);
+
+#endif // _MSM_VIDC_STATE_H_
diff --git a/drivers/media/platform/qcom/iris/vidc/src/msm_vidc_state.c b/drivers/media/platform/qcom/iris/vidc/src/msm_vidc_state.c
new file mode 100644
index 0000000..0361e69
--- /dev/null
+++ b/drivers/media/platform/qcom/iris/vidc/src/msm_vidc_state.c
@@ -0,0 +1,1607 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2020-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include "msm_vidc.h"
+#include "msm_vidc_control.h"
+#include "msm_vidc_core.h"
+#include "msm_vidc_debug.h"
+#include "msm_vidc_driver.h"
+#include "msm_vidc_state.h"
+#include "msm_vidc_vb2.h"
+#include "venus_hfi.h"
+
+bool core_in_valid_state(struct msm_vidc_core *core)
+{
+	return (core->state == MSM_VIDC_CORE_INIT ||
+		core->state == MSM_VIDC_CORE_INIT_WAIT);
+}
+
+bool is_core_state(struct msm_vidc_core *core, enum msm_vidc_core_state state)
+{
+	return core->state == state;
+}
+
+bool is_drc_pending(struct msm_vidc_inst *inst)
+{
+	return is_sub_state(inst, MSM_VIDC_DRC) &&
+		is_sub_state(inst, MSM_VIDC_DRC_LAST_BUFFER);
+}
+
+bool is_drain_pending(struct msm_vidc_inst *inst)
+{
+	return is_sub_state(inst, MSM_VIDC_DRAIN) &&
+		is_sub_state(inst, MSM_VIDC_DRAIN_LAST_BUFFER);
+}
+
+static const char * const core_state_name_arr[] = {
+	[MSM_VIDC_CORE_DEINIT] =    "CORE_DEINIT",
+	[MSM_VIDC_CORE_INIT_WAIT] = "CORE_INIT_WAIT",
+	[MSM_VIDC_CORE_INIT] =      "CORE_INIT",
+	[MSM_VIDC_CORE_ERROR] =     "CORE_ERROR",
+};
+
+const char *core_state_name(enum msm_vidc_core_state state)
+{
+	const char *name = "UNKNOWN STATE";
+
+	if (state >= ARRAY_SIZE(core_state_name_arr))
+		goto exit;
+
+	name = core_state_name_arr[state];
+
+exit:
+	return name;
+}
+
+static const char * const event_name_arr[] = {
+	[MSM_VIDC_TRY_FMT] =   "TRY_FMT",
+	[MSM_VIDC_S_FMT] =     "S_FMT",
+	[MSM_VIDC_REQBUFS] =   "REQBUFS",
+	[MSM_VIDC_S_CTRL] =    "S_CTRL",
+	[MSM_VIDC_STREAMON] =  "STREAMON",
+	[MSM_VIDC_STREAMOFF] = "STREAMOFF",
+	[MSM_VIDC_CMD_START] = "CMD_START",
+	[MSM_VIDC_CMD_STOP] =  "CMD_STOP",
+	[MSM_VIDC_BUF_QUEUE] = "BUF_QUEUE",
+};
+
+static const char *event_name(enum msm_vidc_event event)
+{
+	const char *name = "UNKNOWN EVENT";
+
+	if (event >= ARRAY_SIZE(event_name_arr))
+		goto exit;
+
+	name = event_name_arr[event];
+
+exit:
+	return name;
+}
+
+static int __strict_inst_check(struct msm_vidc_inst *inst, const char *function)
+{
+	bool fatal = !mutex_is_locked(&inst->lock);
+
+	WARN_ON(fatal);
+
+	return fatal ? -EINVAL : 0;
+}
+
+struct msm_vidc_core_sub_state_allow {
+	enum msm_vidc_core_state       state;
+	enum msm_vidc_allow            allow;
+	u32                            sub_state_mask;
+};
+
+static u32 msm_vidc_core_sub_state_mask(enum msm_vidc_core_state state,
+					u32 allow)
+{
+	int cnt;
+	u32 sub_state_mask = 0;
+	static struct msm_vidc_core_sub_state_allow sub_state[] = {
+		/* state, allow, sub_state */
+		{MSM_VIDC_CORE_DEINIT,    MSM_VIDC_ALLOW,       CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_DEINIT,     MSM_VIDC_IGNORE,     CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_INIT_WAIT,  MSM_VIDC_ALLOW,      CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_INIT_WAIT,  MSM_VIDC_DISALLOW,   CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_INIT_WAIT,  MSM_VIDC_IGNORE,     CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_INIT,       MSM_VIDC_ALLOW,      CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_ERROR,      MSM_VIDC_ALLOW,      CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+		{MSM_VIDC_CORE_ERROR,      MSM_VIDC_DISALLOW,   CORE_SUBSTATE_POWER_ENABLE       |
+								CORE_SUBSTATE_GDSC_HANDOFF       |
+								CORE_SUBSTATE_PM_SUSPEND         |
+								CORE_SUBSTATE_FW_PWR_CTRL        |
+								CORE_SUBSTATE_PAGE_FAULT         |
+								CORE_SUBSTATE_CPU_WATCHDOG       |
+								CORE_SUBSTATE_VIDEO_UNRESPONSIVE },
+	};
+
+	for (cnt = 0; cnt < ARRAY_SIZE(sub_state); cnt++) {
+		if (sub_state[cnt].state == state && sub_state[cnt].allow == allow) {
+			sub_state_mask = sub_state[cnt].sub_state_mask;
+			break;
+		}
+	}
+
+	return sub_state_mask;
+}
+
+static int msm_vidc_core_deinit_state(struct msm_vidc_core *core,
+				      enum msm_vidc_core_event_type type,
+				      struct msm_vidc_event_data *data)
+{
+	int rc = 0;
+
+	switch (type) {
+	case CORE_EVENT_UPDATE_SUB_STATE:
+	{
+		u32 req_sub_state = data->edata.uval;
+		u32 allow_mask = msm_vidc_core_sub_state_mask(core->state, MSM_VIDC_ALLOW);
+
+		req_sub_state = data->edata.uval;
+
+		/* none of the requested substate supported */
+		if (!(req_sub_state & allow_mask)) {
+			d_vpr_e("%s: invalid substate update request %#x\n",
+				__func__, req_sub_state);
+			return -EINVAL;
+		}
+
+		/* update core substate */
+		core->sub_state |= req_sub_state & allow_mask;
+		return rc;
+	}
+	default: {
+		d_vpr_e("%s: unexpected core event type %u\n",
+			__func__, type);
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_core_init_wait_state(struct msm_vidc_core *core,
+					 enum msm_vidc_core_event_type type,
+					 struct msm_vidc_event_data *data)
+{
+	int rc = 0;
+
+	switch (type) {
+	case CORE_EVENT_UPDATE_SUB_STATE:
+	{
+		u32 req_sub_state = data->edata.uval;
+		u32 allow_mask = msm_vidc_core_sub_state_mask(core->state, MSM_VIDC_ALLOW);
+
+		req_sub_state = data->edata.uval;
+
+		/* none of the requested substate supported */
+		if (!(req_sub_state & allow_mask)) {
+			d_vpr_e("%s: invalid substate update request %#x\n",
+				__func__, req_sub_state);
+			return -EINVAL;
+		}
+
+		/* update core substate */
+		core->sub_state |= req_sub_state & allow_mask;
+		return rc;
+	}
+	default: {
+		d_vpr_e("%s: unexpected core event type %u\n",
+			__func__, type);
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_core_init_state(struct msm_vidc_core *core,
+				    enum msm_vidc_core_event_type type,
+				    struct msm_vidc_event_data *data)
+{
+	int rc = 0;
+
+	switch (type) {
+	case CORE_EVENT_UPDATE_SUB_STATE:
+	{
+		u32 req_sub_state = data->edata.uval;
+		u32 allow_mask = msm_vidc_core_sub_state_mask(core->state, MSM_VIDC_ALLOW);
+
+		req_sub_state = data->edata.uval;
+
+		/* none of the requested substate supported */
+		if (!(req_sub_state & allow_mask)) {
+			d_vpr_e("%s: invalid substate update request %#x\n",
+				__func__, req_sub_state);
+			return -EINVAL;
+		}
+
+		/* update core substate */
+		core->sub_state |= req_sub_state & allow_mask;
+		return rc;
+	}
+	default: {
+		d_vpr_e("%s: unexpected core event type %u\n",
+			__func__, type);
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_core_error_state(struct msm_vidc_core *core,
+				     enum msm_vidc_core_event_type type,
+				     struct msm_vidc_event_data *data)
+{
+	int rc = 0;
+
+	switch (type) {
+	case CORE_EVENT_UPDATE_SUB_STATE:
+	{
+		u32 req_sub_state = data->edata.uval;
+		u32 allow_mask = msm_vidc_core_sub_state_mask(core->state, MSM_VIDC_ALLOW);
+
+		req_sub_state = data->edata.uval;
+
+		/* none of the requested substate supported */
+		if (!(req_sub_state & allow_mask)) {
+			d_vpr_e("%s: invalid substate update request %#x\n",
+				__func__, req_sub_state);
+			return -EINVAL;
+		}
+
+		/* update core substate */
+		core->sub_state |= req_sub_state & allow_mask;
+		return rc;
+	}
+	default: {
+		d_vpr_e("%s: unexpected core event type %u\n",
+			__func__, type);
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+struct msm_vidc_core_state_handle {
+	enum msm_vidc_core_state   state;
+	int			 (*handle)(struct msm_vidc_core *core,
+					   enum msm_vidc_core_event_type type,
+					   struct msm_vidc_event_data *data);
+};
+
+static struct msm_vidc_core_state_handle
+	*msm_vidc_get_core_state_handle(enum msm_vidc_core_state req_state)
+{
+	int cnt;
+	struct msm_vidc_core_state_handle *core_state_handle = NULL;
+	static struct msm_vidc_core_state_handle state_handle[] = {
+		{MSM_VIDC_CORE_DEINIT,      msm_vidc_core_deinit_state      },
+		{MSM_VIDC_CORE_INIT_WAIT,   msm_vidc_core_init_wait_state   },
+		{MSM_VIDC_CORE_INIT,        msm_vidc_core_init_state        },
+		{MSM_VIDC_CORE_ERROR,       msm_vidc_core_error_state       },
+	};
+
+	for (cnt = 0; cnt < ARRAY_SIZE(state_handle); cnt++) {
+		if (state_handle[cnt].state == req_state) {
+			core_state_handle = &state_handle[cnt];
+			break;
+		}
+	}
+
+	/* if req_state does not exist in the table */
+	if (cnt == ARRAY_SIZE(state_handle)) {
+		d_vpr_e("%s: invalid core state \"%s\" requested\n",
+			__func__, core_state_name(req_state));
+		return core_state_handle;
+	}
+
+	return core_state_handle;
+}
+
+int msm_vidc_update_core_state(struct msm_vidc_core *core,
+			       enum msm_vidc_core_state request_state, const char *func)
+{
+	struct msm_vidc_core_state_handle *state_handle = NULL;
+	int rc = 0;
+
+	/* get core state handler for requested state */
+	state_handle = msm_vidc_get_core_state_handle(request_state);
+	if (!state_handle)
+		return -EINVAL;
+
+	d_vpr_h("%s: core state changed to %s from %s\n", func,
+		core_state_name(state_handle->state), core_state_name(core->state));
+
+	/* finally update core state and handler */
+	core->state = state_handle->state;
+	core->state_handle = state_handle->handle;
+
+	return rc;
+}
+
+struct msm_vidc_core_state_allow {
+	enum msm_vidc_core_state   from;
+	enum msm_vidc_core_state   to;
+	enum msm_vidc_allow        allow;
+};
+
+enum msm_vidc_allow msm_vidc_allow_core_state_change(struct msm_vidc_core *core,
+						     enum msm_vidc_core_state req_state)
+{
+	int cnt;
+	enum msm_vidc_allow allow = MSM_VIDC_DISALLOW;
+	static struct msm_vidc_core_state_allow state[] = {
+		/* from, to, allow */
+		{MSM_VIDC_CORE_DEINIT,      MSM_VIDC_CORE_DEINIT,      MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_DEINIT,      MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_DEINIT,      MSM_VIDC_CORE_INIT,        MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CORE_DEINIT,      MSM_VIDC_CORE_ERROR,       MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_CORE_DEINIT,      MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_CORE_INIT,        MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_CORE_ERROR,       MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_INIT,        MSM_VIDC_CORE_DEINIT,      MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_INIT,        MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CORE_INIT,        MSM_VIDC_CORE_INIT,        MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_INIT,        MSM_VIDC_CORE_ERROR,       MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_ERROR,       MSM_VIDC_CORE_DEINIT,      MSM_VIDC_ALLOW     },
+		{MSM_VIDC_CORE_ERROR,       MSM_VIDC_CORE_INIT_WAIT,   MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_ERROR,       MSM_VIDC_CORE_INIT,        MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CORE_ERROR,       MSM_VIDC_CORE_ERROR,       MSM_VIDC_IGNORE    },
+	};
+
+	for (cnt = 0; cnt < ARRAY_SIZE(state); cnt++) {
+		if (state[cnt].from == core->state && state[cnt].to == req_state) {
+			allow = state[cnt].allow;
+			break;
+		}
+	}
+
+	return allow;
+}
+
+int msm_vidc_change_core_state(struct msm_vidc_core *core,
+			       enum msm_vidc_core_state request_state, const char *func)
+{
+	enum msm_vidc_allow allow;
+	int rc = 0;
+
+	/* core must be locked */
+	rc = __strict_check(core, func);
+	if (rc) {
+		d_vpr_e("%s(): core was not locked\n", func);
+		return rc;
+	}
+
+	/* current and requested state is same */
+	if (core->state == request_state)
+		return 0;
+
+	/* check if requested state movement is allowed */
+	allow = msm_vidc_allow_core_state_change(core, request_state);
+	if (allow == MSM_VIDC_IGNORE) {
+		d_vpr_h("%s: %s core state change %s -> %s\n", func,
+			allow_name(allow), core_state_name(core->state),
+			core_state_name(request_state));
+		return 0;
+	} else if (allow == MSM_VIDC_DISALLOW) {
+		d_vpr_e("%s: %s core state change %s -> %s\n", func,
+			allow_name(allow), core_state_name(core->state),
+			core_state_name(request_state));
+		return -EINVAL;
+	}
+
+	/* go ahead and update core state */
+	return msm_vidc_update_core_state(core, request_state, func);
+}
+
+bool is_core_sub_state(struct msm_vidc_core *core, enum msm_vidc_core_sub_state sub_state)
+{
+	return !!(core->sub_state & sub_state);
+}
+
+const char *core_sub_state_name(enum msm_vidc_core_sub_state sub_state)
+{
+	switch (sub_state) {
+	case CORE_SUBSTATE_NONE:                 return "NONE ";
+	case CORE_SUBSTATE_GDSC_HANDOFF:         return "GDSC_HANDOFF ";
+	case CORE_SUBSTATE_PM_SUSPEND:           return "PM_SUSPEND ";
+	case CORE_SUBSTATE_FW_PWR_CTRL:          return "FW_PWR_CTRL ";
+	case CORE_SUBSTATE_POWER_ENABLE:         return "POWER_ENABLE ";
+	case CORE_SUBSTATE_PAGE_FAULT:           return "PAGE_FAULT ";
+	case CORE_SUBSTATE_CPU_WATCHDOG:         return "CPU_WATCHDOG ";
+	case CORE_SUBSTATE_VIDEO_UNRESPONSIVE:   return "VIDEO_UNRESPONSIVE ";
+	case CORE_SUBSTATE_MAX:                  return "MAX ";
+	}
+
+	return "UNKNOWN ";
+}
+
+static int prepare_core_sub_state_name(enum msm_vidc_core_sub_state sub_state,
+				       char *buf, u32 size)
+{
+	int i = 0;
+
+	if (!buf || !size)
+		return -EINVAL;
+
+	strscpy(buf, "\0", size);
+	if (sub_state == CORE_SUBSTATE_NONE) {
+		strscpy(buf, "CORE_SUBSTATE_NONE", size);
+		return 0;
+	}
+
+	for (i = 0; BIT(i) < CORE_SUBSTATE_MAX; i++) {
+		if (sub_state & BIT(i))
+			strlcat(buf, core_sub_state_name(BIT(i)), size);
+	}
+
+	return 0;
+}
+
+static int msm_vidc_update_core_sub_state(struct msm_vidc_core *core,
+					  enum msm_vidc_core_sub_state sub_state,
+					  const char *func)
+{
+	struct msm_vidc_event_data data;
+	char sub_state_name[MAX_NAME_LENGTH];
+	int ret = 0, rc = 0;
+
+	/* no substate update */
+	if (!sub_state)
+		return 0;
+
+	/* invoke update core substate event */
+	memset(&data, 0, sizeof(struct msm_vidc_event_data));
+	data.edata.uval = sub_state;
+	rc = core->state_handle(core, CORE_EVENT_UPDATE_SUB_STATE, &data);
+	if (rc) {
+		ret = prepare_core_sub_state_name(sub_state, sub_state_name,
+						  sizeof(sub_state_name) - 1);
+		if (!ret)
+			d_vpr_e("%s: state %s, requested invalid core substate %s\n",
+				func, core_state_name(core->state), sub_state_name);
+		return rc;
+	}
+
+	return rc;
+}
+
+int msm_vidc_change_core_sub_state(struct msm_vidc_core *core,
+				   enum msm_vidc_core_sub_state clear_sub_state,
+				   enum msm_vidc_core_sub_state set_sub_state,
+				   const char *func)
+{
+	int rc = 0;
+	enum msm_vidc_core_sub_state prev_sub_state;
+
+	/* core must be locked */
+	rc = __strict_check(core, func);
+	if (rc) {
+		d_vpr_e("%s(): core was not locked\n", func);
+		return rc;
+	}
+
+	/* sanitize core state handler */
+	if (!core->state_handle) {
+		d_vpr_e("%s: invalid core state handle\n", __func__);
+		return -EINVAL;
+	}
+
+	/* final value will not change */
+	if (clear_sub_state == set_sub_state)
+		return 0;
+
+	/* sanitize clear & set value */
+	if (set_sub_state > CORE_SUBSTATE_MAX ||
+	    clear_sub_state > CORE_SUBSTATE_MAX) {
+		d_vpr_e("%s: invalid sub states. clear %#x or set %#x\n",
+			func, clear_sub_state, set_sub_state);
+		return -EINVAL;
+	}
+
+	prev_sub_state = core->sub_state;
+
+	/* set sub state */
+	rc = msm_vidc_update_core_sub_state(core, set_sub_state, func);
+	if (rc)
+		return rc;
+
+	/* check if all core substates updated */
+	if ((core->sub_state & set_sub_state) != set_sub_state)
+		d_vpr_e("%s: all substates not updated %#x, expected %#x\n",
+			func, core->sub_state & set_sub_state, set_sub_state);
+
+	/* clear sub state */
+	core->sub_state &= ~clear_sub_state;
+
+	/* print substates only when there is a change */
+	if (core->sub_state != prev_sub_state) {
+		rc = prepare_core_sub_state_name(core->sub_state, core->sub_state_name,
+						 sizeof(core->sub_state_name) - 1);
+		if (!rc)
+			d_vpr_h("%s: core sub state changed to %s\n", func, core->sub_state_name);
+	}
+
+	return 0;
+}
+
+/* do not modify the state names as it is used in test scripts */
+static const char * const state_name_arr[] = {
+	[MSM_VIDC_OPEN] =             "OPEN",
+	[MSM_VIDC_INPUT_STREAMING] =  "INPUT_STREAMING",
+	[MSM_VIDC_OUTPUT_STREAMING] = "OUTPUT_STREAMING",
+	[MSM_VIDC_STREAMING] =        "STREAMING",
+	[MSM_VIDC_CLOSE] =            "CLOSE",
+	[MSM_VIDC_ERROR] =            "ERROR",
+};
+
+const char *state_name(enum msm_vidc_state state)
+{
+	const char *name = "UNKNOWN STATE";
+
+	if (state >= ARRAY_SIZE(state_name_arr))
+		goto exit;
+
+	name = state_name_arr[state];
+
+exit:
+	return name;
+}
+
+bool is_state(struct msm_vidc_inst *inst, enum msm_vidc_state state)
+{
+	return inst->state == state;
+}
+
+bool is_sub_state(struct msm_vidc_inst *inst, enum msm_vidc_sub_state sub_state)
+{
+	return (inst->sub_state & sub_state);
+}
+
+const char *sub_state_name(enum msm_vidc_sub_state sub_state)
+{
+	switch (sub_state) {
+	case MSM_VIDC_DRAIN:               return "DRAIN ";
+	case MSM_VIDC_DRC:                 return "DRC ";
+	case MSM_VIDC_DRAIN_LAST_BUFFER:   return "DRAIN_LAST_BUFFER ";
+	case MSM_VIDC_DRC_LAST_BUFFER:     return "DRC_LAST_BUFFER ";
+	case MSM_VIDC_INPUT_PAUSE:         return "INPUT_PAUSE ";
+	case MSM_VIDC_OUTPUT_PAUSE:        return "OUTPUT_PAUSE ";
+	}
+
+	return "SUB_STATE_NONE";
+}
+
+static int prepare_sub_state_name(enum msm_vidc_sub_state sub_state,
+				  char *buf, u32 size)
+{
+	int i = 0;
+
+	if (!buf || !size)
+		return -EINVAL;
+
+	strscpy(buf, "\0", size);
+	if (sub_state == MSM_VIDC_SUB_STATE_NONE) {
+		strscpy(buf, "SUB_STATE_NONE", size);
+		return 0;
+	}
+
+	for (i = 0; i < MSM_VIDC_MAX_SUB_STATES; i++) {
+		if (sub_state & BIT(i))
+			strlcat(buf, sub_state_name(BIT(i)), size);
+	}
+
+	return 0;
+}
+
+struct msm_vidc_state_allow {
+	enum msm_vidc_state        from;
+	enum msm_vidc_state        to;
+	enum msm_vidc_allow        allow;
+};
+
+static enum msm_vidc_allow msm_vidc_allow_state_change(struct msm_vidc_inst *inst,
+						       enum msm_vidc_state req_state)
+{
+	int cnt;
+	enum msm_vidc_allow allow = MSM_VIDC_DISALLOW;
+	static struct msm_vidc_state_allow state[] = {
+		/* from, to, allow */
+		{MSM_VIDC_OPEN,             MSM_VIDC_OPEN,               MSM_VIDC_IGNORE    },
+		{MSM_VIDC_OPEN,             MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OPEN,             MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OPEN,             MSM_VIDC_STREAMING,          MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_OPEN,             MSM_VIDC_CLOSE,              MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OPEN,             MSM_VIDC_ERROR,              MSM_VIDC_ALLOW     },
+
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_OPEN,               MSM_VIDC_ALLOW     },
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_IGNORE    },
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_STREAMING,          MSM_VIDC_ALLOW     },
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_CLOSE,              MSM_VIDC_ALLOW     },
+		{MSM_VIDC_INPUT_STREAMING,  MSM_VIDC_ERROR,              MSM_VIDC_ALLOW     },
+
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_OPEN,               MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_IGNORE    },
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_STREAMING,          MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_CLOSE,              MSM_VIDC_ALLOW     },
+		{MSM_VIDC_OUTPUT_STREAMING, MSM_VIDC_ERROR,              MSM_VIDC_ALLOW     },
+
+		{MSM_VIDC_STREAMING,        MSM_VIDC_OPEN,               MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_STREAMING,        MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_ALLOW     },
+		{MSM_VIDC_STREAMING,        MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_ALLOW     },
+		{MSM_VIDC_STREAMING,        MSM_VIDC_STREAMING,          MSM_VIDC_IGNORE    },
+		{MSM_VIDC_STREAMING,        MSM_VIDC_CLOSE,              MSM_VIDC_ALLOW     },
+		{MSM_VIDC_STREAMING,        MSM_VIDC_ERROR,              MSM_VIDC_ALLOW     },
+
+		{MSM_VIDC_CLOSE,            MSM_VIDC_OPEN,               MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CLOSE,            MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CLOSE,            MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CLOSE,            MSM_VIDC_STREAMING,          MSM_VIDC_DISALLOW  },
+		{MSM_VIDC_CLOSE,            MSM_VIDC_CLOSE,              MSM_VIDC_IGNORE    },
+		{MSM_VIDC_CLOSE,            MSM_VIDC_ERROR,              MSM_VIDC_IGNORE    },
+
+		{MSM_VIDC_ERROR,            MSM_VIDC_OPEN,               MSM_VIDC_IGNORE    },
+		{MSM_VIDC_ERROR,            MSM_VIDC_INPUT_STREAMING,    MSM_VIDC_IGNORE    },
+		{MSM_VIDC_ERROR,            MSM_VIDC_OUTPUT_STREAMING,   MSM_VIDC_IGNORE    },
+		{MSM_VIDC_ERROR,            MSM_VIDC_STREAMING,          MSM_VIDC_IGNORE    },
+		{MSM_VIDC_ERROR,            MSM_VIDC_CLOSE,              MSM_VIDC_IGNORE    },
+		{MSM_VIDC_ERROR,            MSM_VIDC_ERROR,              MSM_VIDC_IGNORE    },
+	};
+
+	for (cnt = 0; cnt < ARRAY_SIZE(state); cnt++) {
+		if (state[cnt].from == inst->state && state[cnt].to == req_state) {
+			allow = state[cnt].allow;
+			break;
+		}
+	}
+
+	return allow;
+}
+
+static int msm_vidc_open_state(struct msm_vidc_inst *inst,
+			       enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_TRY_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* allow try_fmt request in open state */
+		rc = msm_vidc_try_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* allow s_fmt request in open state */
+		rc = msm_vidc_s_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_CTRL:
+	{
+		struct v4l2_ctrl *ctrl = (struct v4l2_ctrl *)data;
+
+		/* allow set_control request in open state */
+		rc = msm_vidc_s_ctrl(inst, ctrl);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_REQBUFS:
+	{
+		struct v4l2_requestbuffers *b = (struct v4l2_requestbuffers *)data;
+
+		/* allow reqbufs request in open state */
+		rc = msm_vidc_reqbufs(inst, b);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMON:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* allow streamon request in open state */
+		rc = msm_vidc_start_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* ignore streamoff request in open state */
+		i_vpr_h(inst, "%s: streamoff of (%s) ignored in state (%s)\n",
+			__func__, v4l2_type_name(q->type), state_name(inst->state));
+		break;
+	}
+	case MSM_VIDC_CMD_START:
+	{
+		/* disallow start cmd request in open state */
+		i_vpr_e(inst, "%s: (%s) not allowed, sub_state (%s)\n",
+			__func__, event_name(event), inst->sub_state_name);
+
+		return -EBUSY;
+	}
+	case MSM_VIDC_CMD_STOP:
+	{
+		/* ignore stop cmd request in open state */
+		i_vpr_h(inst, "%s: (%s) ignored, sub_state (%s)\n",
+			__func__, event_name(event), inst->sub_state_name);
+		break;
+	}
+	case MSM_VIDC_BUF_QUEUE:
+	{
+		struct msm_vidc_buffer *buf = (struct msm_vidc_buffer *)data;
+
+		/* defer qbuf request in open state */
+		print_vidc_buffer(VIDC_LOW, "low ", "qbuf deferred", inst, buf);
+		break;
+	}
+	default:
+	{
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_input_streaming_state(struct msm_vidc_inst *inst,
+					  enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_BUF_QUEUE:
+	{
+		struct msm_vidc_buffer *buf = (struct msm_vidc_buffer *)data;
+
+		/* disallow */
+		if (!is_input_buffer(buf->type) && !is_output_buffer(buf->type)) {
+			i_vpr_e(inst, "%s: invalid buf type %u\n", __func__, buf->type);
+			return -EINVAL;
+		}
+
+		/* defer output port */
+		if (is_output_buffer(buf->type)) {
+			print_vidc_buffer(VIDC_LOW, "low ", "qbuf deferred", inst, buf);
+			return 0;
+		}
+
+		rc = msm_vidc_buf_queue(inst, buf);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_TRY_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* disallow */
+		if (f->type == INPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(f->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_try_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* disallow */
+		if (f->type == INPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(f->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_s_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_CTRL:
+	{
+		struct v4l2_ctrl *ctrl = (struct v4l2_ctrl *)data;
+		u32 cap_id = msm_vidc_get_cap_id(inst, ctrl->id);
+
+		if (cap_id == INST_CAP_NONE) {
+			i_vpr_e(inst, "%s: invalid cap_id %u\n", __func__, cap_id);
+			return -EINVAL;
+		}
+
+		/* disallow */
+		if (is_decode_session(inst)) {
+			/* check dynamic allowed if master port is streaming */
+			if (!(inst->capabilities[cap_id].flags & CAP_FLAG_DYNAMIC_ALLOWED)) {
+				i_vpr_e(inst, "%s: cap_id %#x not allowed in state %s\n",
+					__func__, cap_id, state_name(inst->state));
+				return -EINVAL;
+			}
+		}
+
+		rc = msm_vidc_s_ctrl(inst, ctrl);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_REQBUFS:
+	{
+		struct v4l2_requestbuffers *b = (struct v4l2_requestbuffers *)data;
+
+		/* disallow */
+		if (b->type == INPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(b->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_reqbufs(inst, b);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMON:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* disallow */
+		if (q->type == INPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) type\n",
+				__func__, event_name(event), v4l2_type_name(q->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_start_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* ignore */
+		if (q->type == OUTPUT_MPLANE) {
+			i_vpr_h(inst, "%s: streamoff of (%s) ignored in state (%s)\n",
+				__func__, v4l2_type_name(q->type), state_name(inst->state));
+			return 0;
+		}
+
+		/* sanitize type field */
+		if (q->type != INPUT_MPLANE) {
+			i_vpr_e(inst, "%s: invalid type %d\n", __func__, q->type);
+			return -EINVAL;
+		}
+
+		rc = msm_vidc_stop_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_START:
+	{
+		/* disallow if START called for non DRC/drain cases */
+		if (!is_drc_pending(inst) && !is_drain_pending(inst)) {
+			i_vpr_e(inst, "%s: (%s) not allowed, sub_state (%s)\n",
+				__func__, event_name(event), inst->sub_state_name);
+			return -EBUSY;
+		}
+
+		/* client would call start(resume) to complete DRC/drain sequence */
+		rc = msm_vidc_start_cmd(inst);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_STOP:
+	{
+		/* back to back drain not allowed */
+		if (is_sub_state(inst, MSM_VIDC_DRAIN)) {
+			i_vpr_e(inst, "%s: drain (%s) not allowed, sub_state (%s)\n\n",
+				__func__, event_name(event), inst->sub_state_name);
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_stop_cmd(inst);
+		if (rc)
+			return rc;
+		break;
+	}
+	default:
+	{
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_output_streaming_state(struct msm_vidc_inst *inst,
+					   enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_BUF_QUEUE:
+	{
+		struct msm_vidc_buffer *buf = (struct msm_vidc_buffer *)data;
+
+		/* disallow */
+		if (!is_input_buffer(buf->type) && !is_output_buffer(buf->type)) {
+			i_vpr_e(inst, "%s: invalid buf type %u\n", __func__, buf->type);
+			return -EINVAL;
+		}
+
+		/* defer input port */
+		if (is_input_buffer(buf->type)) {
+			print_vidc_buffer(VIDC_LOW, "low ", "qbuf deferred", inst, buf);
+			return 0;
+		}
+
+		rc = msm_vidc_buf_queue(inst, buf);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_TRY_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* disallow */
+		if (f->type == OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(f->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_try_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_FMT:
+	{
+		struct v4l2_format *f = (struct v4l2_format *)data;
+
+		/* disallow */
+		if (f->type == OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(f->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_s_fmt(inst, f);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_CTRL:
+	{
+		struct v4l2_ctrl *ctrl = (struct v4l2_ctrl *)data;
+		u32 cap_id = msm_vidc_get_cap_id(inst, ctrl->id);
+
+		if (cap_id == INST_CAP_NONE) {
+			i_vpr_e(inst, "%s: invalid cap_id %u\n", __func__, cap_id);
+			return -EINVAL;
+		}
+
+		/* disallow */
+		if (is_encode_session(inst)) {
+			/* check dynamic allowed if master port is streaming */
+			if (!(inst->capabilities[cap_id].flags & CAP_FLAG_DYNAMIC_ALLOWED)) {
+				i_vpr_e(inst, "%s: cap_id %#x not allowed in state %s\n",
+					__func__, cap_id, state_name(inst->state));
+				return -EINVAL;
+			}
+		}
+
+		rc = msm_vidc_s_ctrl(inst, ctrl);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_REQBUFS:
+	{
+		struct v4l2_requestbuffers *b = (struct v4l2_requestbuffers *)data;
+
+		/* disallow */
+		if (b->type == OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) port\n",
+				__func__, event_name(event), v4l2_type_name(b->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_reqbufs(inst, b);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMON:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* disallow */
+		if (q->type == OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: (%s) not allowed for (%s) type\n",
+				__func__, event_name(event), v4l2_type_name(q->type));
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_start_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* ignore */
+		if (q->type == INPUT_MPLANE) {
+			i_vpr_h(inst, "%s: streamoff of (%s) ignored in state (%s)\n",
+				__func__, v4l2_type_name(q->type), state_name(inst->state));
+			return 0;
+		}
+
+		/* sanitize type field */
+		if (q->type != OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: invalid type %d\n", __func__, q->type);
+			return -EINVAL;
+		}
+
+		rc = msm_vidc_stop_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_START:
+	{
+		/* disallow if START called for non DRC/drain cases */
+		if (!is_drc_pending(inst) && !is_drain_pending(inst)) {
+			i_vpr_e(inst, "%s: (%s) not allowed, sub_state (%s)\n",
+				__func__, event_name(event), inst->sub_state_name);
+			return -EBUSY;
+		}
+
+		/* client would call start(resume) to complete DRC/drain sequence */
+		rc = msm_vidc_start_cmd(inst);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_STOP:
+	{
+		/* drain not allowed as input is not streaming */
+		i_vpr_e(inst, "%s: drain (%s) not allowed, sub state %s\n",
+			__func__, event_name(event), inst->sub_state_name);
+		return -EBUSY;
+	}
+	default: {
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_streaming_state(struct msm_vidc_inst *inst,
+				    enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_BUF_QUEUE:
+	{
+		struct msm_vidc_buffer *buf = (struct msm_vidc_buffer *)data;
+
+		/* disallow */
+		if (!is_input_buffer(buf->type) && !is_output_buffer(buf->type)) {
+			i_vpr_e(inst, "%s: invalid buf type %u\n", __func__, buf->type);
+			return -EINVAL;
+		}
+
+		rc = msm_vidc_buf_queue(inst, buf);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_S_CTRL:
+	{
+		struct v4l2_ctrl *ctrl = (struct v4l2_ctrl *)data;
+		u32 cap_id = msm_vidc_get_cap_id(inst, ctrl->id);
+
+		if (cap_id == INST_CAP_NONE) {
+			i_vpr_e(inst, "%s: invalid cap_id %u\n", __func__, cap_id);
+			return -EINVAL;
+		}
+
+		/* disallow */
+		if (!(inst->capabilities[cap_id].flags & CAP_FLAG_DYNAMIC_ALLOWED)) {
+			i_vpr_e(inst, "%s: cap_id %#x not allowed in state %s\n",
+				__func__, cap_id, state_name(inst->state));
+			return -EINVAL;
+		}
+
+		rc = msm_vidc_s_ctrl(inst, ctrl);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		/* sanitize type field */
+		if (q->type != INPUT_MPLANE && q->type != OUTPUT_MPLANE) {
+			i_vpr_e(inst, "%s: invalid type %d\n", __func__, q->type);
+			return -EINVAL;
+		}
+
+		rc = msm_vidc_stop_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_START:
+	{
+		/* disallow if START called for non DRC/drain cases */
+		if (!is_drc_pending(inst) && !is_drain_pending(inst)) {
+			i_vpr_e(inst, "%s: (%s) not allowed, sub_state (%s)\n",
+				__func__, event_name(event), inst->sub_state_name);
+			return -EBUSY;
+		}
+
+		/* client would call start(resume) to complete DRC/drain sequence */
+		rc = msm_vidc_start_cmd(inst);
+		if (rc)
+			return rc;
+		break;
+	}
+	case MSM_VIDC_CMD_STOP:
+	{
+		/* back to back drain not allowed */
+		if (is_sub_state(inst, MSM_VIDC_DRAIN)) {
+			i_vpr_e(inst, "%s: drain (%s) not allowed, sub_state (%s)\n\n",
+				__func__, event_name(event), inst->sub_state_name);
+			return -EBUSY;
+		}
+
+		rc = msm_vidc_stop_cmd(inst);
+		if (rc)
+			return rc;
+		break;
+	}
+	default: {
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_close_state(struct msm_vidc_inst *inst,
+				enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		rc = msm_vidc_stop_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	default: {
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+static int msm_vidc_error_state(struct msm_vidc_inst *inst,
+				enum msm_vidc_event event, void *data)
+{
+	int rc = 0;
+
+	/* inst must be locked */
+	rc = __strict_inst_check(inst, __func__);
+	if (rc) {
+		i_vpr_e(inst, "%s(): inst was not locked\n", __func__);
+		return -EINVAL;
+	}
+
+	switch (event) {
+	case MSM_VIDC_STREAMOFF:
+	{
+		struct vb2_queue *q = (struct vb2_queue *)data;
+
+		rc = msm_vidc_stop_streaming(inst, q);
+		if (rc)
+			return rc;
+		break;
+	}
+	default: {
+		i_vpr_e(inst, "%s: unexpected event %s\n", __func__, event_name(event));
+		return -EINVAL;
+	}
+	}
+
+	return rc;
+}
+
+struct msm_vidc_state_handle {
+	enum msm_vidc_state   state;
+	int                 (*handle)(struct msm_vidc_inst *inst,
+				      enum msm_vidc_event event, void *data);
+};
+
+static struct msm_vidc_state_handle *msm_vidc_get_state_handle(struct msm_vidc_inst *inst,
+							       enum msm_vidc_state req_state)
+{
+	int cnt;
+	struct msm_vidc_state_handle *inst_state_handle = NULL;
+	static struct msm_vidc_state_handle state_handle[] = {
+		{MSM_VIDC_OPEN,             msm_vidc_open_state             },
+		{MSM_VIDC_INPUT_STREAMING,  msm_vidc_input_streaming_state  },
+		{MSM_VIDC_OUTPUT_STREAMING, msm_vidc_output_streaming_state },
+		{MSM_VIDC_STREAMING,        msm_vidc_streaming_state        },
+		{MSM_VIDC_CLOSE,            msm_vidc_close_state            },
+		{MSM_VIDC_ERROR,            msm_vidc_error_state            },
+	};
+
+	for (cnt = 0; cnt < ARRAY_SIZE(state_handle); cnt++) {
+		if (state_handle[cnt].state == req_state) {
+			inst_state_handle = &state_handle[cnt];
+			break;
+		}
+	}
+
+	/* check if req_state does not exist in the table */
+	if (cnt == ARRAY_SIZE(state_handle)) {
+		i_vpr_e(inst, "%s: invalid state %s\n", __func__, state_name(req_state));
+		return inst_state_handle;
+	}
+
+	return inst_state_handle;
+}
+
+int msm_vidc_update_state(struct msm_vidc_inst *inst,
+			  enum msm_vidc_state request_state, const char *func)
+{
+	struct msm_vidc_state_handle *state_handle = NULL;
+	int rc = 0;
+
+	/* get inst state handler for requested state */
+	state_handle = msm_vidc_get_state_handle(inst, request_state);
+	if (!state_handle)
+		return -EINVAL;
+
+	if (request_state == MSM_VIDC_ERROR)
+		i_vpr_e(inst, FMT_STRING_STATE_CHANGE,
+			func, state_name(request_state), state_name(inst->state));
+	else
+		i_vpr_h(inst, FMT_STRING_STATE_CHANGE,
+			func, state_name(request_state), state_name(inst->state));
+
+	/* finally update inst state and handler */
+	inst->state = state_handle->state;
+	inst->event_handle = state_handle->handle;
+
+	return rc;
+}
+
+int msm_vidc_change_state(struct msm_vidc_inst *inst,
+			  enum msm_vidc_state request_state, const char *func)
+{
+	enum msm_vidc_allow allow;
+	int rc;
+
+	if (is_session_error(inst)) {
+		i_vpr_h(inst,
+			"%s: inst is in bad state, can not change state to %s\n",
+			func, state_name(request_state));
+		return 0;
+	}
+
+	/* current and requested state is same */
+	if (inst->state == request_state)
+		return 0;
+
+	/* check if requested state movement is allowed */
+	allow = msm_vidc_allow_state_change(inst, request_state);
+	if (allow != MSM_VIDC_ALLOW) {
+		i_vpr_e(inst, "%s: %s state change %s -> %s\n", func,
+			allow_name(allow), state_name(inst->state),
+			state_name(request_state));
+		return (allow == MSM_VIDC_DISALLOW ? -EINVAL : 0);
+	}
+
+	/* go ahead and update inst state */
+	rc = msm_vidc_update_state(inst, request_state, func);
+	if (rc)
+		return rc;
+
+	return 0;
+}
+
+struct msm_vidc_sub_state_allow {
+	enum msm_vidc_state            state;
+	enum msm_vidc_allow            allow;
+	u32                            sub_state_mask;
+};
+
+static int msm_vidc_set_sub_state(struct msm_vidc_inst *inst,
+				  enum msm_vidc_sub_state sub_state, const char *func)
+{
+	char sub_state_name[MAX_NAME_LENGTH];
+	int cnt, rc = 0;
+	static struct msm_vidc_sub_state_allow sub_state_allow[] = {
+		/* state, allow, sub_state */
+		{MSM_VIDC_OPEN,              MSM_VIDC_DISALLOW,    MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_INPUT_PAUSE         |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+
+		{MSM_VIDC_INPUT_STREAMING,   MSM_VIDC_DISALLOW,    MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+		{MSM_VIDC_INPUT_STREAMING,   MSM_VIDC_ALLOW,       MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_INPUT_PAUSE          },
+
+		{MSM_VIDC_OUTPUT_STREAMING,  MSM_VIDC_DISALLOW,    MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_INPUT_PAUSE          },
+		{MSM_VIDC_OUTPUT_STREAMING,  MSM_VIDC_ALLOW,       MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+
+		{MSM_VIDC_STREAMING,         MSM_VIDC_ALLOW,       MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_INPUT_PAUSE         |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+
+		{MSM_VIDC_CLOSE,             MSM_VIDC_ALLOW,       MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_INPUT_PAUSE         |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+
+		{MSM_VIDC_ERROR,             MSM_VIDC_ALLOW,       MSM_VIDC_DRC                 |
+								   MSM_VIDC_DRAIN               |
+								   MSM_VIDC_DRC_LAST_BUFFER     |
+								   MSM_VIDC_DRAIN_LAST_BUFFER   |
+								   MSM_VIDC_INPUT_PAUSE         |
+								   MSM_VIDC_OUTPUT_PAUSE         },
+	};
+
+	/* no substate to update */
+	if (!sub_state)
+		return 0;
+
+	/* check if any substate is disallowed */
+	for (cnt = 0; cnt < ARRAY_SIZE(sub_state_allow); cnt++) {
+		/* skip other states */
+		if (sub_state_allow[cnt].state != inst->state)
+			continue;
+
+		/* continue if not disallowed */
+		if (sub_state_allow[cnt].allow != MSM_VIDC_DISALLOW)
+			continue;
+
+		if (sub_state_allow[cnt].sub_state_mask & sub_state) {
+			prepare_sub_state_name(sub_state, sub_state_name, sizeof(sub_state_name));
+			i_vpr_e(inst, "%s: state (%s), disallow substate (%s)\n",
+				func, state_name(inst->state), sub_state_name);
+			return -EINVAL;
+		}
+	}
+
+	/* remove ignorable substates from a given substate */
+	for (cnt = 0; cnt < ARRAY_SIZE(sub_state_allow); cnt++) {
+		/* skip other states */
+		if (sub_state_allow[cnt].state != inst->state)
+			continue;
+
+		/* continue if not ignored */
+		if (sub_state_allow[cnt].allow != MSM_VIDC_IGNORE)
+			continue;
+
+		if (sub_state_allow[cnt].sub_state_mask & sub_state) {
+			prepare_sub_state_name(sub_state, sub_state_name, sizeof(sub_state_name));
+			i_vpr_h(inst, "%s: state (%s), ignore substate (%s)\n",
+				func, state_name(inst->state), sub_state_name);
+
+			/* remove ignorable substate bits from actual */
+			sub_state &= ~(sub_state_allow[cnt].sub_state_mask & sub_state);
+			break;
+		}
+	}
+
+	/* check if all substate bits are allowed */
+	for (cnt = 0; cnt < ARRAY_SIZE(sub_state_allow); cnt++) {
+		/* skip other states */
+		if (sub_state_allow[cnt].state != inst->state)
+			continue;
+
+		/* continue if not allowed */
+		if (sub_state_allow[cnt].allow != MSM_VIDC_ALLOW)
+			continue;
+
+		if ((sub_state_allow[cnt].sub_state_mask & sub_state) != sub_state) {
+			prepare_sub_state_name(sub_state, sub_state_name, sizeof(sub_state_name));
+			i_vpr_e(inst, "%s: state (%s), not all substates allowed (%s)\n",
+				func, state_name(inst->state), sub_state_name);
+			return -EINVAL;
+		}
+	}
+
+	/* update substate */
+	inst->sub_state |= sub_state;
+
+	return rc;
+}
+
+int msm_vidc_change_sub_state(struct msm_vidc_inst *inst,
+			      enum msm_vidc_sub_state clear_sub_state,
+			      enum msm_vidc_sub_state set_sub_state, const char *func)
+{
+	enum msm_vidc_sub_state prev_sub_state;
+	int rc = 0;
+
+	if (is_session_error(inst)) {
+		i_vpr_h(inst,
+			"%s: inst is in bad state, can not change sub state\n", func);
+		return 0;
+	}
+
+	/* final value will not change */
+	if (!clear_sub_state && !set_sub_state)
+		return 0;
+
+	/* sanitize clear & set value */
+	if ((clear_sub_state & set_sub_state) ||
+	    set_sub_state > MSM_VIDC_MAX_SUB_STATE_VALUE ||
+	    clear_sub_state > MSM_VIDC_MAX_SUB_STATE_VALUE) {
+		i_vpr_e(inst, "%s: invalid sub states to clear %#x or set %#x\n",
+			func, clear_sub_state, set_sub_state);
+		return -EINVAL;
+	}
+
+	prev_sub_state = inst->sub_state;
+
+	/* set sub state */
+	rc = msm_vidc_set_sub_state(inst, set_sub_state, __func__);
+	if (rc)
+		return rc;
+
+	/* clear sub state */
+	inst->sub_state &= ~clear_sub_state;
+
+	/* print substates only when there is a change */
+	if (inst->sub_state != prev_sub_state) {
+		rc = prepare_sub_state_name(inst->sub_state, inst->sub_state_name,
+					    sizeof(inst->sub_state_name));
+		if (!rc)
+			i_vpr_h(inst, "%s: state %s and sub state changed to %s\n",
+				func, state_name(inst->state), inst->sub_state_name);
+	}
+
+	return 0;
+}