[PATCH 2/2] crypto: sun4i-ss: enable pm_runtime

[Corentin Labbe <clabbe.montjoie@xxxxxxxxx>]

This patch enables power management on the Security System.

Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
---
 drivers/crypto/sunxi-ss/sun4i-ss-cipher.c |  5 +++
 drivers/crypto/sunxi-ss/sun4i-ss-core.c   | 42 ++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
index fa4b1b47822e..1fedec9e83b0 100644
--- a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
@@ -10,6 +10,8 @@
  *
  * You could find the datasheet in Documentation/arm/sunxi.rst
  */
+
+#include <linux/pm_runtime.h>
 #include "sun4i-ss.h"
 
 static int noinline_for_stack sun4i_ss_opti_poll(struct skcipher_request *areq)
@@ -497,13 +499,16 @@ int sun4i_ss_cipher_init(struct crypto_tfm *tfm)
 		return PTR_ERR(op->fallback_tfm);
 	}
 
+	pm_runtime_get_sync(op->ss->dev);
 	return 0;
 }
 
 void sun4i_ss_cipher_exit(struct crypto_tfm *tfm)
 {
 	struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);
+
 	crypto_free_sync_skcipher(op->fallback_tfm);
+	pm_runtime_put_sync(op->ss->dev);
 }
 
 /* check and set the AES key, prepare the mode to be used */
diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-core.c b/drivers/crypto/sunxi-ss/sun4i-ss-core.c
index 2c9ff01dddfc..5e6e1a308f60 100644
--- a/drivers/crypto/sunxi-ss/sun4i-ss-core.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-core.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <crypto/scatterwalk.h>
 #include <linux/scatterlist.h>
 #include <linux/interrupt.h>
@@ -258,6 +259,37 @@ static int sun4i_ss_enable(struct sun4i_ss_ctx *ss)
 	return err;
 }
 
+#ifdef CONFIG_PM
+static int sun4i_ss_pm_suspend(struct device *dev)
+{
+	struct sun4i_ss_ctx *ss = dev_get_drvdata(dev);
+
+	sun4i_ss_disable(ss);
+	return 0;
+}
+
+static int sun4i_ss_pm_resume(struct device *dev)
+{
+	struct sun4i_ss_ctx *ss = dev_get_drvdata(dev);
+
+	return sun4i_ss_enable(ss);
+}
+#endif
+
+const struct dev_pm_ops sun4i_ss_pm_ops = {
+	SET_RUNTIME_PM_OPS(sun4i_ss_pm_suspend, sun4i_ss_pm_resume, NULL)
+};
+
+static void sun4i_ss_pm_init(struct sun4i_ss_ctx *ss)
+{
+	pm_runtime_use_autosuspend(ss->dev);
+	pm_runtime_set_autosuspend_delay(ss->dev, 1000);
+
+	pm_runtime_get_noresume(ss->dev);
+	pm_runtime_set_active(ss->dev);
+	pm_runtime_enable(ss->dev);
+}
+
 static int sun4i_ss_probe(struct platform_device *pdev)
 {
 	u32 v;
@@ -357,9 +389,12 @@ static int sun4i_ss_probe(struct platform_device *pdev)
 	writel(0, ss->base + SS_CTL);
 
 	ss->dev = &pdev->dev;
+	platform_set_drvdata(pdev, ss);
 
 	spin_lock_init(&ss->slock);
 
+	sun4i_ss_pm_init(ss);
+
 	for (i = 0; i < ARRAY_SIZE(ss_algs); i++) {
 		ss_algs[i].ss = ss;
 		switch (ss_algs[i].type) {
@@ -388,7 +423,8 @@ static int sun4i_ss_probe(struct platform_device *pdev)
 			break;
 		}
 	}
-	platform_set_drvdata(pdev, ss);
+
+	pm_runtime_put_sync(ss->dev);
 	return 0;
 error_alg:
 	i--;
@@ -405,6 +441,7 @@ static int sun4i_ss_probe(struct platform_device *pdev)
 			break;
 		}
 	}
+	pm_runtime_disable(ss->dev);
 error_enable:
 	sun4i_ss_disable(ss);
 	return err;
@@ -429,6 +466,8 @@ static int sun4i_ss_remove(struct platform_device *pdev)
 		}
 	}
 
+	pm_runtime_disable(ss->dev);
+
 	writel(0, ss->base + SS_CTL);
 	sun4i_ss_disable(ss);
 	return 0;
@@ -445,6 +484,7 @@ static struct platform_driver sun4i_ss_driver = {
 	.remove         = sun4i_ss_remove,
 	.driver         = {
 		.name           = "sun4i-ss",
+		.pm		= &sun4i_ss_pm_ops,
 		.of_match_table	= a20ss_crypto_of_match_table,
 	},
 };
-- 
2.21.0