[PATCH v4 1/4] firmware: qcom: scm: Add support for tsens reinit workaround

[Bhupesh Sharma]

Some versions of Qualcomm tsens controller might enter a
'bad state' while running stability tests causing sensor
temperatures/interrupts status to be in an 'invalid' state.

It is recommended to re-initialize the tsens controller
via trustzone (secure registers) using scm call(s) when that
happens.

Add support for the same in the qcom_scm driver.

Cc: Amit Kucheria <amitk@xxxxxxxxxx>
Cc: Thara Gopinath <thara.gopinath@xxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: linux-arm-msm@xxxxxxxxxxxxxxx
Reviewed-by: Bjorn Andersson <andersson@xxxxxxxxxx>
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx>
---
 drivers/firmware/qcom_scm.c | 15 +++++++++++++++
 drivers/firmware/qcom_scm.h |  4 ++++
 include/linux/qcom_scm.h    |  2 ++
 3 files changed, 21 insertions(+)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index cdbfe54c8146..93adcc046a62 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -858,6 +858,21 @@ int qcom_scm_mem_protect_video_var(u32 cp_start, u32 cp_size,
 }
 EXPORT_SYMBOL(qcom_scm_mem_protect_video_var);
 
+int qcom_scm_tsens_reinit(void)
+{
+	int ret;
+	const struct qcom_scm_desc desc = {
+		.svc = QCOM_SCM_SVC_TSENS,
+		.cmd = QCOM_SCM_TSENS_INIT_ID,
+	};
+	struct qcom_scm_res res;
+
+	ret = qcom_scm_call(__scm->dev, &desc, &res);
+
+	return ret ? : res.result[0];
+}
+EXPORT_SYMBOL(qcom_scm_tsens_reinit);
+
 static int __qcom_scm_assign_mem(struct device *dev, phys_addr_t mem_region,
 				 size_t mem_sz, phys_addr_t src, size_t src_sz,
 				 phys_addr_t dest, size_t dest_sz)
diff --git a/drivers/firmware/qcom_scm.h b/drivers/firmware/qcom_scm.h
index 0d51eef2472f..5762f02dde7c 100644
--- a/drivers/firmware/qcom_scm.h
+++ b/drivers/firmware/qcom_scm.h
@@ -94,6 +94,10 @@ extern int scm_legacy_call(struct device *dev, const struct qcom_scm_desc *desc,
 #define QCOM_SCM_PIL_PAS_IS_SUPPORTED	0x07
 #define QCOM_SCM_PIL_PAS_MSS_RESET	0x0a
 
+/* TSENS Services and Function IDs */
+#define QCOM_SCM_SVC_TSENS		0x1e
+#define QCOM_SCM_TSENS_INIT_ID		0x5
+
 #define QCOM_SCM_SVC_IO			0x05
 #define QCOM_SCM_IO_READ		0x01
 #define QCOM_SCM_IO_WRITE		0x02
diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
index f8335644a01a..5c37e1658cef 100644
--- a/include/linux/qcom_scm.h
+++ b/include/linux/qcom_scm.h
@@ -124,4 +124,6 @@ extern int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
 extern int qcom_scm_lmh_profile_change(u32 profile_id);
 extern bool qcom_scm_lmh_dcvsh_available(void);
 
+extern int qcom_scm_tsens_reinit(void);
+
 #endif
-- 
2.37.1