crypto: rockchip - introduce PM

Add runtime PM support for rockchip crypto.
Reviewed-by: John Keeping <john@metanate.com>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/rockchip/rk3288_crypto.c

@@ -65,6 +65,48 @@ static void rk_crypto_disable_clk(struct rk_crypto_info *dev)
 	clk_disable_unprepare(dev->sclk);
 }
 
+/*
+ * Power management strategy: The device is suspended unless a TFM exists for
+ * one of the algorithms proposed by this driver.
+ */
+static int rk_crypto_pm_suspend(struct device *dev)
+{
+	struct rk_crypto_info *rkdev = dev_get_drvdata(dev);
+
+	rk_crypto_disable_clk(rkdev);
+	return 0;
+}
+
+static int rk_crypto_pm_resume(struct device *dev)
+{
+	struct rk_crypto_info *rkdev = dev_get_drvdata(dev);
+
+	return rk_crypto_enable_clk(rkdev);
+}
+
+static const struct dev_pm_ops rk_crypto_pm_ops = {
+	SET_RUNTIME_PM_OPS(rk_crypto_pm_suspend, rk_crypto_pm_resume, NULL)
+};
+
+static int rk_crypto_pm_init(struct rk_crypto_info *rkdev)
+{
+	int err;
+
+	pm_runtime_use_autosuspend(rkdev->dev);
+	pm_runtime_set_autosuspend_delay(rkdev->dev, 2000);
+
+	err = pm_runtime_set_suspended(rkdev->dev);
+	if (err)
+		return err;
+	pm_runtime_enable(rkdev->dev);
+	return err;
+}
+
+static void rk_crypto_pm_exit(struct rk_crypto_info *rkdev)
+{
+	pm_runtime_disable(rkdev->dev);
+}
+
 static irqreturn_t rk_crypto_irq_handle(int irq, void *dev_id)
 {
 	struct rk_crypto_info *dev  = platform_get_drvdata(dev_id);
@@ -273,7 +315,9 @@ static int rk_crypto_probe(struct platform_device *pdev)
 	crypto_engine_start(crypto_info->engine);
 	init_completion(&crypto_info->complete);
 
-	rk_crypto_enable_clk(crypto_info);
+	err = rk_crypto_pm_init(crypto_info);
+	if (err)
+		goto err_pm;
 
 	err = rk_crypto_register(crypto_info);
 	if (err) {
@@ -294,6 +338,8 @@ static int rk_crypto_probe(struct platform_device *pdev)
 	return 0;
 
 err_register_alg:
+	rk_crypto_pm_exit(crypto_info);
+err_pm:
 	crypto_engine_exit(crypto_info->engine);
 err_crypto:
 	dev_err(dev, "Crypto Accelerator not successfully registered\n");
@@ -308,7 +354,7 @@ static int rk_crypto_remove(struct platform_device *pdev)
 	debugfs_remove_recursive(crypto_tmp->dbgfs_dir);
 #endif
 	rk_crypto_unregister();
-	rk_crypto_disable_clk(crypto_tmp);
+	rk_crypto_pm_exit(crypto_tmp);
 	crypto_engine_exit(crypto_tmp->engine);
 	return 0;
 }
@@ -318,6 +364,7 @@ static struct platform_driver crypto_driver = {
 	.remove		= rk_crypto_remove,
 	.driver		= {
 		.name	= "rk3288-crypto",
+		.pm		= &rk_crypto_pm_ops,
 		.of_match_table	= crypto_of_id_table,
 	},
 };

drivers/crypto/rockchip/rk3288_crypto.h

@@ -9,6 +9,7 @@
 #include <linux/interrupt.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
+#include <linux/pm_runtime.h>
 #include <linux/scatterlist.h>
 #include <crypto/engine.h>
 #include <crypto/internal/hash.h>

drivers/crypto/rockchip/rk3288_crypto_ahash.c

@@ -328,6 +328,7 @@ static int rk_cra_hash_init(struct crypto_tfm *tfm)
 	struct ahash_alg *alg = __crypto_ahash_alg(tfm->__crt_alg);
 
 	const char *alg_name = crypto_tfm_alg_name(tfm);
+	int err;
 
 	algt = container_of(alg, struct rk_crypto_tmp, alg.hash);
 
@@ -349,7 +350,15 @@ static int rk_cra_hash_init(struct crypto_tfm *tfm)
 	tctx->enginectx.op.prepare_request = rk_hash_prepare;
 	tctx->enginectx.op.unprepare_request = rk_hash_unprepare;
 
+	err = pm_runtime_resume_and_get(tctx->dev->dev);
+	if (err < 0)
+		goto error_pm;
+
 	return 0;
+error_pm:
+	crypto_free_ahash(tctx->fallback_tfm);
+
+	return err;
 }
 
 static void rk_cra_hash_exit(struct crypto_tfm *tfm)
@@ -357,6 +366,7 @@ static void rk_cra_hash_exit(struct crypto_tfm *tfm)
 	struct rk_ahash_ctx *tctx = crypto_tfm_ctx(tfm);
 
 	crypto_free_ahash(tctx->fallback_tfm);
+	pm_runtime_put_autosuspend(tctx->dev->dev);
 }
 
 struct rk_crypto_tmp rk_ahash_sha1 = {

drivers/crypto/rockchip/rk3288_crypto_skcipher.c

@@ -454,6 +454,7 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
 	struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
 	const char *name = crypto_tfm_alg_name(&tfm->base);
 	struct rk_crypto_tmp *algt;
+	int err;
 
 	algt = container_of(alg, struct rk_crypto_tmp, alg.skcipher);
 
@@ -471,7 +472,14 @@ static int rk_ablk_init_tfm(struct crypto_skcipher *tfm)
 
 	ctx->enginectx.op.do_one_request = rk_cipher_run;
 
+	err = pm_runtime_resume_and_get(ctx->dev->dev);
+	if (err < 0)
+		goto error_pm;
+
 	return 0;
+error_pm:
+	crypto_free_skcipher(ctx->fallback_tfm);
+	return err;
 }
 
 static void rk_ablk_exit_tfm(struct crypto_skcipher *tfm)
@@ -480,6 +488,7 @@ static void rk_ablk_exit_tfm(struct crypto_skcipher *tfm)
 
 	memzero_explicit(ctx->key, ctx->keylen);
 	crypto_free_skcipher(ctx->fallback_tfm);
+	pm_runtime_put_autosuspend(ctx->dev->dev);
 }
 
 struct rk_crypto_tmp rk_ecb_aes_alg = {