From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932309AbbCLVAi (ORCPT ); Thu, 12 Mar 2015 17:00:38 -0400 Received: from mail-ie0-f175.google.com ([209.85.223.175]:35191 "EHLO mail-ie0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932217AbbCLVAe (ORCPT ); Thu, 12 Mar 2015 17:00:34 -0400 From: Dmitry Torokhov To: Herbert Xu Cc: linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/6] hwrng: add devm_* interfaces Date: Thu, 12 Mar 2015 14:00:02 -0700 Message-Id: <1426194007-22182-2-git-send-email-dmitry.torokhov@gmail.com> X-Mailer: git-send-email 2.2.0.rc0.207.ga3a616c In-Reply-To: <1426194007-22182-1-git-send-email-dmitry.torokhov@gmail.com> References: <1426194007-22182-1-git-send-email-dmitry.torokhov@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This change adds devm_hwrng_register and devm_hwrng_unregister which use can simplify error unwinding and unbinding code paths in device drivers. Signed-off-by: Dmitry Torokhov --- drivers/char/hw_random/core.c | 42 ++++++++++++++++++++++++++++++++++++++++++ include/linux/hw_random.h | 4 ++++ 2 files changed, 46 insertions(+) diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 32a8a86..83161dd 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -536,6 +536,48 @@ void hwrng_unregister(struct hwrng *rng) } EXPORT_SYMBOL_GPL(hwrng_unregister); +static void devm_hwrng_release(struct device *dev, void *res) +{ + hwrng_unregister(*(struct hwrng **)res); +} + +static int devm_hwrng_match(struct device *dev, void *res, void *data) +{ + struct hwrng **r = res; + + if (WARN_ON(!r || !*r)) + return 0; + + return *r == data; +} + +int devm_hwrng_register(struct device *dev, struct hwrng *rng) +{ + struct hwrng **ptr; + int error; + + ptr = devres_alloc(devm_hwrng_release, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + error = hwrng_register(rng); + if (error) { + devres_free(ptr); + return error; + } + + *ptr = rng; + devres_add(dev, ptr); + return 0; +} +EXPORT_SYMBOL_GPL(devm_hwrng_register); + +void devm_hwrng_unregister(struct device *dev, struct hwrng *rng) +{ + devres_release(dev, devm_hwrng_release, devm_hwrng_match, rng); +} +EXPORT_SYMBOL_GPL(devm_hwrng_unregister); + static int __init hwrng_modinit(void) { return register_miscdev(); diff --git a/include/linux/hw_random.h b/include/linux/hw_random.h index eb7b414..4f7d8f4 100644 --- a/include/linux/hw_random.h +++ b/include/linux/hw_random.h @@ -50,10 +50,14 @@ struct hwrng { struct completion cleanup_done; }; +struct device; + /** Register a new Hardware Random Number Generator driver. */ extern int hwrng_register(struct hwrng *rng); +extern int devm_hwrng_register(struct device *dev, struct hwrng *rng); /** Unregister a Hardware Random Number Generator driver. */ extern void hwrng_unregister(struct hwrng *rng); +extern void devm_hwrng_unregister(struct device *dve, struct hwrng *rng); /** Feed random bits into the pool. */ extern void add_hwgenerator_randomness(const char *buffer, size_t count, size_t entropy); -- 2.2.0.rc0.207.ga3a616c