[PATCH 3/3] firmware: qcom: scm: drop the __scm global

[Albert Esteve]

Stop publishing a driver-wide singleton. Mark the instance
ready with scm->available, look it up from the platform driver
for module-parameter stores, and use platform_get_drvdata() on
shutdown.

Signed-off-by: Albert Esteve <aesteve@xxxxxxxxxx>
---
 drivers/firmware/qcom/qcom_scm.c | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index 73e9752e3cca..68cd8dc622c6 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -63,6 +63,9 @@ struct qcom_scm {
 
 	struct qcom_tzmem_pool *mempool;
 	unsigned int wq_cnt;
+
+	/* Published with smp_store_release() once the SCM API is usable. */
+	int available;
 };
 
 struct qcom_scm_current_perm_info {
@@ -174,8 +177,6 @@ static const char * const download_mode_name[] = {
 	[QCOM_DLOAD_BOTHDUMP]	= "full,mini",
 };
 
-static struct qcom_scm *__scm;
-
 static int qcom_scm_clk_enable(struct qcom_scm *scm)
 {
 	int ret;
@@ -1962,7 +1963,7 @@ EXPORT_SYMBOL_GPL(qcom_scm_lmh_dcvsh_available);
  * This is only supposed to be called once by the TZMem module. It takes the
  * SCM struct device as argument and uses it to pass the call as at the time
  * the SHM Bridge is enabled, the SCM is not yet fully set up and doesn't
- * accept global user calls. Don't try to use the __scm pointer here.
+ * accept global user calls.
  */
 int qcom_scm_shm_bridge_enable(struct device *scm_dev)
 {
@@ -2657,7 +2658,7 @@ static void qcom_scm_qtee_init(struct qcom_scm *scm)
 bool qcom_scm_is_available(struct qcom_scm *scm)
 {
 	/* Paired with smp_store_release() in qcom_scm_probe */
-	return scm && scm == smp_load_acquire(&__scm);
+	return scm && smp_load_acquire(&scm->available);
 }
 EXPORT_SYMBOL_GPL(qcom_scm_is_available);
 
@@ -2817,7 +2818,7 @@ static int set_download_mode(const char *val, const struct kernel_param *kp)
 
 	download_mode = ret;
 	/* Pairs with smp_store_release() in qcom_scm_probe(). */
-	scm = smp_load_acquire(&__scm);
+	scm = qcom_scm_get();
 	if (scm)
 		qcom_scm_set_download_mode(scm, download_mode);
 
@@ -2858,7 +2859,7 @@ static int set_minidump_dest(const char *val, const struct kernel_param *kp)
 	minidump_dest = minidump_dest_map[i].val;
 
 	/* Pairs with smp_store_release() in qcom_scm_probe(). */
-	scm = smp_load_acquire(&__scm);
+	scm = qcom_scm_get();
 	if (scm && scm->minidump_sram && (download_mode & QCOM_DLOAD_MINIDUMP))
 		writel_relaxed(minidump_dest, scm->minidump_sram);
 
@@ -2983,7 +2984,7 @@ static int qcom_scm_probe(struct platform_device *pdev)
 	 * be called after the TrustZone memory pool is initialized and the
 	 * waitqueue interrupt requested.
 	 */
-	smp_store_release(&__scm, scm);
+	smp_store_release(&scm->available, 1);
 
 	__get_convention(scm->dev);
 
@@ -3033,8 +3034,10 @@ static int qcom_scm_probe(struct platform_device *pdev)
 
 static void qcom_scm_shutdown(struct platform_device *pdev)
 {
+	struct qcom_scm *scm = platform_get_drvdata(pdev);
+
 	/* Clean shutdown, disable download mode to allow normal restart */
-	qcom_scm_set_download_mode(__scm, QCOM_DLOAD_NODUMP);
+	qcom_scm_set_download_mode(scm, QCOM_DLOAD_NODUMP);
 	qcom_pas_ops_unregister();
 }
 

-- 
2.55.0