crypto: sun4i-ss - enable pm_runtime

This patch enables power management on the Security System.
sun4i-ss now depends on PM because it simplify code and prevent some ifdef.
But this is not a problem since arch maintainer want ARCH_SUNXI to
depend on PM in the future.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index a467b16..3e51bae 100644 (file)
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -660,6 +660,7 @@ config CRYPTO_DEV_IMGTEC_HASH
 config CRYPTO_DEV_SUN4I_SS
        tristate "Support for Allwinner Security System cryptographic accelerator"
        depends on ARCH_SUNXI && !64BIT
+       depends on PM
        select CRYPTO_MD5
        select CRYPTO_SHA1
        select CRYPTO_AES

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
index 6536fd4..e5954a6 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
@@ -480,6 +480,7 @@ int sun4i_ss_cipher_init(struct crypto_tfm *tfm)
        struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);
        struct sun4i_ss_alg_template *algt;
        const char *name = crypto_tfm_alg_name(tfm);
+       int err;
 
        memset(op, 0, sizeof(struct sun4i_tfm_ctx));
 
@@ -497,13 +498,22 @@ int sun4i_ss_cipher_init(struct crypto_tfm *tfm)
                return PTR_ERR(op->fallback_tfm);
        }
 
+       err = pm_runtime_get_sync(op->ss->dev);
+       if (err < 0)
+               goto error_pm;
+
        return 0;
+error_pm:
+       crypto_free_sync_skcipher(op->fallback_tfm);
+       return err;
 }
 
 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(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 6c2db5d..814cd12 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss-core.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-core.c
@@ -44,7 +44,8 @@ static struct sun4i_ss_alg_template ss_algs[] = {
                                .cra_blocksize = MD5_HMAC_BLOCK_SIZE,
                                .cra_ctxsize = sizeof(struct sun4i_req_ctx),
                                .cra_module = THIS_MODULE,
-                               .cra_init = sun4i_hash_crainit
+                               .cra_init = sun4i_hash_crainit,
+                               .cra_exit = sun4i_hash_craexit,
                        }
                }
        }
@@ -70,7 +71,8 @@ static struct sun4i_ss_alg_template ss_algs[] = {
                                .cra_blocksize = SHA1_BLOCK_SIZE,
                                .cra_ctxsize = sizeof(struct sun4i_req_ctx),
                                .cra_module = THIS_MODULE,
-                               .cra_init = sun4i_hash_crainit
+                               .cra_init = sun4i_hash_crainit,
+                               .cra_exit = sun4i_hash_craexit,
                        }
                }
        }
@@ -223,17 +225,26 @@ static struct sun4i_ss_alg_template ss_algs[] = {
 #endif
 };
 
-static void sun4i_ss_disable(struct sun4i_ss_ctx *ss)
+/*
+ * Power management strategy: The device is suspended unless a TFM exists for
+ * one of the algorithms proposed by this driver.
+ */
+static int sun4i_ss_pm_suspend(struct device *dev)
 {
+       struct sun4i_ss_ctx *ss = dev_get_drvdata(dev);
+
        if (ss->reset)
                reset_control_assert(ss->reset);
 
        clk_disable_unprepare(ss->ssclk);
        clk_disable_unprepare(ss->busclk);
+       return 0;
 }
 
-static int sun4i_ss_enable(struct sun4i_ss_ctx *ss)
+static int sun4i_ss_pm_resume(struct device *dev)
 {
+       struct sun4i_ss_ctx *ss = dev_get_drvdata(dev);
+
        int err;
 
        err = clk_prepare_enable(ss->busclk);
@@ -258,10 +269,38 @@ static int sun4i_ss_enable(struct sun4i_ss_ctx *ss)
 
        return err;
 err_enable:
-       sun4i_ss_disable(ss);
+       sun4i_ss_pm_suspend(dev);
+       return err;
+}
+
+const struct dev_pm_ops sun4i_ss_pm_ops = {
+       SET_RUNTIME_PM_OPS(sun4i_ss_pm_suspend, sun4i_ss_pm_resume, NULL)
+};
+
+/*
+ * When power management is enabled, this function enables the PM and set the
+ * device as suspended
+ * When power management is disabled, this function just enables the device
+ */
+static int sun4i_ss_pm_init(struct sun4i_ss_ctx *ss)
+{
+       int err;
+
+       pm_runtime_use_autosuspend(ss->dev);
+       pm_runtime_set_autosuspend_delay(ss->dev, 2000);
+
+       err = pm_runtime_set_suspended(ss->dev);
+       if (err)
+               return err;
+       pm_runtime_enable(ss->dev);
        return err;
 }
 
+static void sun4i_ss_pm_exit(struct sun4i_ss_ctx *ss)
+{
+       pm_runtime_disable(ss->dev);
+}
+
 static int sun4i_ss_probe(struct platform_device *pdev)
 {
        u32 v;
@@ -308,10 +347,6 @@ static int sun4i_ss_probe(struct platform_device *pdev)
                ss->reset = NULL;
        }
 
-       err = sun4i_ss_enable(ss);
-       if (err)
-               goto error_enable;
-
        /*
         * Check that clock have the correct rates given in the datasheet
         * Try to set the clock to the maximum allowed
@@ -319,7 +354,7 @@ static int sun4i_ss_probe(struct platform_device *pdev)
        err = clk_set_rate(ss->ssclk, cr_mod);
        if (err) {
                dev_err(&pdev->dev, "Cannot set clock rate to ssclk\n");
-               goto error_enable;
+               return err;
        }
 
        /*
@@ -347,12 +382,26 @@ static int sun4i_ss_probe(struct platform_device *pdev)
                dev_warn(&pdev->dev, "Clock ss is at %lu (%lu MHz) (must be <= %lu)\n",
                         cr, cr / 1000000, cr_mod);
 
+       ss->dev = &pdev->dev;
+       platform_set_drvdata(pdev, ss);
+
+       spin_lock_init(&ss->slock);
+
+       err = sun4i_ss_pm_init(ss);
+       if (err)
+               return err;
+
        /*
         * Datasheet named it "Die Bonding ID"
         * I expect to be a sort of Security System Revision number.
         * Since the A80 seems to have an other version of SS
         * this info could be useful
         */
+
+       err = pm_runtime_get_sync(ss->dev);
+       if (err < 0)
+               goto error_pm;
+
        writel(SS_ENABLED, ss->base + SS_CTL);
        v = readl(ss->base + SS_CTL);
        v >>= 16;
@@ -360,9 +409,7 @@ static int sun4i_ss_probe(struct platform_device *pdev)
        dev_info(&pdev->dev, "Die ID %d\n", v);
        writel(0, ss->base + SS_CTL);
 
-       ss->dev = &pdev->dev;
-
-       spin_lock_init(&ss->slock);
+       pm_runtime_put_sync(ss->dev);
 
        for (i = 0; i < ARRAY_SIZE(ss_algs); i++) {
                ss_algs[i].ss = ss;
@@ -392,7 +439,6 @@ static int sun4i_ss_probe(struct platform_device *pdev)
                        break;
                }
        }
-       platform_set_drvdata(pdev, ss);
        return 0;
 error_alg:
        i--;
@@ -409,8 +455,8 @@ error_alg:
                        break;
                }
        }
-error_enable:
-       sun4i_ss_disable(ss);
+error_pm:
+       sun4i_ss_pm_exit(ss);
        return err;
 }
 
@@ -433,8 +479,7 @@ static int sun4i_ss_remove(struct platform_device *pdev)
                }
        }
 
-       writel(0, ss->base + SS_CTL);
-       sun4i_ss_disable(ss);
+       sun4i_ss_pm_exit(ss);
        return 0;
 }
 
@@ -449,6 +494,7 @@ 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,
        },
 };

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c
index fcffba5..9930c9c 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss-hash.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-hash.c
@@ -19,17 +19,29 @@ int sun4i_hash_crainit(struct crypto_tfm *tfm)
        struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);
        struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);
        struct sun4i_ss_alg_template *algt;
+       int err;
 
        memset(op, 0, sizeof(struct sun4i_tfm_ctx));
 
        algt = container_of(alg, struct sun4i_ss_alg_template, alg.hash);
        op->ss = algt->ss;
 
+       err = pm_runtime_get_sync(op->ss->dev);
+       if (err < 0)
+               return err;
+
        crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
                                 sizeof(struct sun4i_req_ctx));
        return 0;
 }
 
+void sun4i_hash_craexit(struct crypto_tfm *tfm)
+{
+       struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);
+
+       pm_runtime_put(op->ss->dev);
+}
+
 /* sun4i_hash_init: initialize request context */
 int sun4i_hash_init(struct ahash_request *areq)
 {

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-prng.c b/drivers/crypto/sunxi-ss/sun4i-ss-prng.c
index 63d6364..729aafd 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss-prng.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-prng.c
@@ -17,7 +17,7 @@ int sun4i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
 {
        struct sun4i_ss_alg_template *algt;
        struct rng_alg *alg = crypto_rng_alg(tfm);
-       int i;
+       int i, err;
        u32 v;
        u32 *data = (u32 *)dst;
        const u32 mode = SS_OP_PRNG | SS_PRNG_CONTINUE | SS_ENABLED;
@@ -28,6 +28,10 @@ int sun4i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
        algt = container_of(alg, struct sun4i_ss_alg_template, alg.rng);
        ss = algt->ss;
 
+       err = pm_runtime_get_sync(ss->dev);
+       if (err < 0)
+               return err;
+
        spin_lock_bh(&ss->slock);
 
        writel(mode, ss->base + SS_CTL);
@@ -52,5 +56,8 @@ int sun4i_ss_prng_generate(struct crypto_rng *tfm, const u8 *src,
 
        writel(0, ss->base + SS_CTL);
        spin_unlock_bh(&ss->slock);
+
+       pm_runtime_put(ss->dev);
+
        return 0;
 }

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss.h b/drivers/crypto/sunxi-ss/sun4i-ss.h
index 35a27a7..60425ac 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss.h
+++ b/drivers/crypto/sunxi-ss/sun4i-ss.h
@@ -22,6 +22,7 @@
 #include <linux/scatterlist.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 #include <crypto/md5.h>
 #include <crypto/skcipher.h>
 #include <crypto/sha.h>
@@ -177,6 +178,7 @@ struct sun4i_req_ctx {
 };
 
 int sun4i_hash_crainit(struct crypto_tfm *tfm);
+void sun4i_hash_craexit(struct crypto_tfm *tfm);
 int sun4i_hash_init(struct ahash_request *areq);
 int sun4i_hash_update(struct ahash_request *areq);
 int sun4i_hash_final(struct ahash_request *areq);