[PATCH v6 6/6] crypto: qcom: Add ACPI support

[Vinod Koul]

From: Timur Tabi <ti...@codeaurora.org>

Add support for probing on ACPI systems, with ACPI HID QCOM8160.

On ACPI systems, clocks are always enabled, the PRNG should
already be enabled, and the register region is read-only.
The driver only verifies that the hardware is already
enabled never tries to disable or configure it.

Signed-off-by: Timur Tabi <ti...@codeaurora.org>
Tested-by: Jeffrey Hugo <jh...@codeaurora.org>
[port to crypto API]
Signed-off-by: Vinod Koul <vk...@kernel.org>
---
 drivers/crypto/qcom-rng.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c
index 80544326e310..e54249ccc009 100644
--- a/drivers/crypto/qcom-rng.c
+++ b/drivers/crypto/qcom-rng.c
@@ -4,6 +4,7 @@
 // Based on msm-rng.c and downstream driver
 
 #include <crypto/internal/rng.h>
+#include <linux/acpi.h>
 #include <linux/clk.h>
 #include <linux/crypto.h>
 #include <linux/module.h>
@@ -168,9 +169,13 @@ static int qcom_rng_probe(struct platform_device *pdev)
        if (IS_ERR(rng->base))
                return PTR_ERR(rng->base);
 
-       rng->clk = devm_clk_get(&pdev->dev, "core");
-       if (IS_ERR(rng->clk))
-               return PTR_ERR(rng->clk);
+       /* ACPI systems have clk already on, so skip clk_get */
+       if (!has_acpi_companion(&pdev->dev)) {
+               rng->clk = devm_clk_get(&pdev->dev, "core");
+               if (IS_ERR(rng->clk))
+                       return PTR_ERR(rng->clk);
+       }
+
 
        rng->skip_init = (unsigned long)device_get_match_data(&pdev->dev);
 
@@ -193,6 +198,14 @@ static int qcom_rng_remove(struct platform_device *pdev)
        return 0;
 }
 
+#if IS_ENABLED(CONFIG_ACPI)
+static const struct acpi_device_id qcom_rng_acpi_match[] = {
+       { .id = "QCOM8160", .driver_data = 1 },
+       {}
+};
+MODULE_DEVICE_TABLE(acpi, qcom_rng_acpi_match);
+#endif
+
 static const struct of_device_id qcom_rng_of_match[] = {
        { .compatible = "qcom,prng", .data = (void *)0},
        { .compatible = "qcom,prng-ee", .data = (void *)1},
@@ -206,6 +219,7 @@ static struct platform_driver qcom_rng_driver = {
        .driver = {
                .name = KBUILD_MODNAME,
                .of_match_table = of_match_ptr(qcom_rng_of_match),
+               .acpi_match_table = ACPI_PTR(qcom_rng_acpi_match),
        }
 };
 module_platform_driver(qcom_rng_driver);
-- 
2.14.4