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

[Corentin Labbe]

This patch enables power management on the Security System.

Signed-off-by: Corentin Labbe <clabbe.montj...@gmail.com>
---
 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