From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753388AbaEAAga (ORCPT ); Wed, 30 Apr 2014 20:36:30 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:56640 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753305AbaEAAg2 (ORCPT ); Wed, 30 Apr 2014 20:36:28 -0400 From: Suman Anna To: Ohad Ben-Cohen , Mark Rutland , Kumar Gala CC: Tony Lindgren , Josh Cartwright , Bjorn Andersson , , , , , Suman Anna Subject: [PATCHv5 RFC 08/15] hwspinlock/core: add support for base id in DT Date: Wed, 30 Apr 2014 19:34:29 -0500 Message-ID: <1398904476-26200-9-git-send-email-s-anna@ti.com> X-Mailer: git-send-email 1.9.2 In-Reply-To: <1398904476-26200-1-git-send-email-s-anna@ti.com> References: <1398904476-26200-1-git-send-email-s-anna@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The HwSpinlock core requires a base id for registering a bank of hwspinlocks. This base id needs to be unique across multiple IP instances of a hwspinlock device, so that each hwlock can be represented uniquely in a system. Support has been added to represent this in DT through a common property 'hwlock-base-id', and retrieve the value through a core OF helper function, of_hwspin_lock_get_base_id(). The representation in DT provides a uniform way of assigning a fixed base value for a hwspinlock device across different SoCs. Signed-off-by: Suman Anna --- Documentation/devicetree/bindings/hwlock/hwlock.txt | 6 ++++++ drivers/hwspinlock/hwspinlock_core.c | 21 +++++++++++++++++++++ include/linux/hwspinlock.h | 1 + 3 files changed, 28 insertions(+) diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt index 32381cc..d538a9b 100644 --- a/Documentation/devicetree/bindings/hwlock/hwlock.txt +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt @@ -18,6 +18,12 @@ Common properties: property is needed on hwlock devices, where the number of supported locks within a hwlock device cannot be read from a register. +- hwlock-base-id: An unique base Id for the locks for a particular hwlock + device. This property is mandatory ONLY if a SoC has + several hwlock devices. + + See documentation on struct hwspinlock_pdata in + include/linux/hwspinlock.h for more details. Hwlock Users: ============= diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 3966c0c..4be1664 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -264,6 +264,27 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) EXPORT_SYMBOL_GPL(__hwspin_unlock); /** + * of_hwspin_lock_get_base_id() - OF helper to retrieve base id + * @dn: device node pointer + * + * This is an OF helper function that can be called by the underlying + * platform-specific implementations, to retrieve the base id for the + * set of locks present within a hwspinlock device instance. + * + * Returns the base id value on success, or an appropriate error code + * as returned by the OF layer + */ +int of_hwspin_lock_get_base_id(struct device_node *dn) +{ + unsigned int val; + int ret; + + ret = of_property_read_u32(dn, "hwlock-base-id", &val); + return ret ? ret : val; +} +EXPORT_SYMBOL_GPL(of_hwspin_lock_get_base_id); + +/** * of_hwspin_lock_get_num_locks() - OF helper to retrieve number of locks * @dn: device node pointer * diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h index 068e628..4857728 100644 --- a/include/linux/hwspinlock.h +++ b/include/linux/hwspinlock.h @@ -64,6 +64,7 @@ struct hwspinlock_pdata { int of_hwspin_lock_simple_xlate(struct hwspinlock_device *bank, const struct of_phandle_args *hwlock_spec); +int of_hwspin_lock_get_base_id(struct device_node *dn); int of_hwspin_lock_get_num_locks(struct device_node *dn); int hwspin_lock_register(struct hwspinlock_device *bank, struct device *dev, const struct hwspinlock_ops *ops, int base_id, int num_locks); -- 1.9.2