[PATCH v2] soc: qcom: smem: fix qcom_smem_is_available and check if __smem is valid

[Christian Marangi <ansuelsmth@gmail.com>]

Commit 7a94d5f31b54 ("soc: qcom: smem: better track SMEM uninitialized
state") changed the usage of __smem and init now as an error pointer
instead of NULL.

qcom_smem_is_available() wasn't updated to reflect this change and also
.qcom_smem_remove doesn't reset it on module exit.

Update both entry to reflect new handling of __smem.

Fixes: 7a94d5f31b54 ("soc: qcom: smem: better track SMEM uninitialized state")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/aSAnR3ECa04CoPqp@stanley.mountain/
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
Changes v2:
- Drop unrelated changes

 drivers/soc/qcom/smem.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c
index fef840b54574..c18a0c946f76 100644
--- a/drivers/soc/qcom/smem.c
+++ b/drivers/soc/qcom/smem.c
@@ -396,7 +396,7 @@ EXPORT_SYMBOL_GPL(qcom_smem_bust_hwspin_lock_by_host);
  */
 bool qcom_smem_is_available(void)
 {
-	return !!__smem;
+	return !IS_ERR(__smem);
 }
 EXPORT_SYMBOL_GPL(qcom_smem_is_available);
 
@@ -1247,7 +1247,8 @@ static void qcom_smem_remove(struct platform_device *pdev)
 {
 	platform_device_unregister(__smem->socinfo);
 
-	__smem = NULL;
+	/* Set to -EPROBE_DEFER to signal unprobed state */
+	__smem = ERR_PTR(-EPROBE_DEFER);
 }
 
 static const struct of_device_id qcom_smem_of_match[] = {
-- 
2.51.0