[PATCH v2 16/17] crypto: qce: Defer probe in case interconnect is not yet initialized

[Bhupesh Sharma]

On some Qualcomm parts the qce crypto driver needs the interconnect between
the crypto block and main memory to be initialized first before the crypto
registers can be accessed. So it makes sense to defer the qce crypto driver
probing in case the interconnect driver is not yet probed.

This fixes the qce probe failure issues when both qce and
interconnect drivers are compiled as static part of the kernel.

Cc: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
Cc: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: Andy Gross <agross@xxxxxxxxxx>
Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Stephen Boyd <sboyd@xxxxxxxxxx>
Cc: Michael Turquette <mturquette@xxxxxxxxxxxx>
Cc: Vinod Koul <vkoul@xxxxxxxxxx>
Cc: dmaengine@xxxxxxxxxxxxxxx
Cc: linux-clk@xxxxxxxxxxxxxxx
Cc: linux-crypto@xxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: bhupesh.linux@xxxxxxxxx
Signed-off-by: Bhupesh Sharma <bhupesh.sharma@xxxxxxxxxx>
---
 drivers/crypto/qce/core.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/crypto/qce/core.c b/drivers/crypto/qce/core.c
index 3e742e9911fa..9915b184f780 100644
--- a/drivers/crypto/qce/core.c
+++ b/drivers/crypto/qce/core.c
@@ -222,6 +222,20 @@ static int qce_crypto_probe(struct platform_device *pdev)
 		return ret;
 
 	qce->mem_path = of_icc_get(qce->dev, "memory");
+
+	/* Check for NULL return path, which indicates
+	 * interconnect API is disabled or the "interconnects"
+	 * DT property is missing.
+	 */
+	if (!qce->mem_path)
+		/* On some qcom parts, the qce crypto block needs interconnect
+		 * paths to be configured before the registers can be accessed.
+		 * Check here for the same.
+		 */
+		if (!strcmp(of_id->compatible, "qcom,ipq6018-qce") ||
+		    !strcmp(of_id->compatible, "qcom,sdm845-qce"))
+			return -EPROBE_DEFER;
+
 	if (IS_ERR(qce->mem_path))
 		return PTR_ERR(qce->mem_path);
 
-- 
2.30.2