Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753975Ab3I0QE2 (ORCPT ); Fri, 27 Sep 2013 12:04:28 -0400 Received: from smtp.codeaurora.org ([198.145.11.231]:49981 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753012Ab3I0QEU convert rfc822-to-8bit (ORCPT ); Fri, 27 Sep 2013 12:04:20 -0400 Subject: Re: [PATCHv2 1/9] hwspinlock/core: add common dt bindings and OF helpers Mime-Version: 1.0 (Apple Message framework v1283) Content-Type: text/plain; charset=us-ascii From: Kumar Gala In-Reply-To: <4df03ac30dcc79132e3acc2e586d0ca99b431258.1379445653.git.s-anna@ti.com> Date: Fri, 27 Sep 2013 11:04:22 -0500 Cc: Ohad Ben-Cohen , Tony Lindgren , Benoit Cousson , Paul Walmsley , , , Content-Transfer-Encoding: 8BIT Message-Id: <14DB8294-1148-446A-A6D3-34E66BA8732C@codeaurora.org> References: <4df03ac30dcc79132e3acc2e586d0ca99b431258.1379445653.git.s-anna@ti.com> To: Suman Anna X-Mailer: Apple Mail (2.1283) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7500 Lines: 202 On Sep 17, 2013, at 2:30 PM, Suman Anna wrote: > All the platform-specific hwlock driver implementations need the > number of locks and the associated base id for registering the > locks present within a hwspinlock device with the driver core. > These two variables are represented by 'hwlock-num-locks' and > 'hwlock-base-id' properties. The documentation and OF helpers to > retrieve these common properties have been added to the driver core. > > Signed-off-by: Suman Anna > --- > .../devicetree/bindings/hwlock/hwlock.txt | 26 +++++++++ > drivers/hwspinlock/hwspinlock_core.c | 61 +++++++++++++++++++++- > include/linux/hwspinlock.h | 11 ++-- > 3 files changed, 93 insertions(+), 5 deletions(-) > create mode 100644 Documentation/devicetree/bindings/hwlock/hwlock.txt > > diff --git a/Documentation/devicetree/bindings/hwlock/hwlock.txt b/Documentation/devicetree/bindings/hwlock/hwlock.txt > new file mode 100644 > index 0000000..789930e > --- /dev/null > +++ b/Documentation/devicetree/bindings/hwlock/hwlock.txt > @@ -0,0 +1,26 @@ > +Generic hwlock bindings > +======================= > + > +Generic bindings that are common to all the hwlock platform specific driver > +implementations, the retrieved values are used for registering the device > +specific parameters with the hwspinlock core. > + > +The validity and need of these common properties may vary from one driver > +implementation to another. Look through the individual hwlock driver > +binding documentations for identifying which are mandatory and which are > +optional for that specific driver. > + > +Common properties: > +- hwlock-base-id: Base Id for the locks for a particular hwlock device. > + This property is used for representing a set of locks > + present in a hwlock device with a unique base id in > + the driver core. This property is mandatory ONLY if a > + SoC has several hwlock devices. > + > + See documentation on struct hwspinlock_pdata in > + linux/hwspinlock.h for more details. > + > +- hwlock-num-locks: Number of locks present in a hwlock device. This > + property is needed on hwlock devices, where the number > + of supported locks within a hwlock device cannot be > + read from a register. > diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c > index 461a0d7..aec32e7 100644 > --- a/drivers/hwspinlock/hwspinlock_core.c > +++ b/drivers/hwspinlock/hwspinlock_core.c > @@ -1,7 +1,7 @@ > /* > * Hardware spinlock framework > * > - * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com > + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com > * > * Contact: Ohad Ben-Cohen > * > @@ -27,6 +27,7 @@ > #include > #include > #include > +#include > > #include "hwspinlock_internal.h" > > @@ -308,6 +309,64 @@ out: > } > > /** > + * 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, -ENODEV on generic failure 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 = -ENODEV; > + > +#ifdef CONFIG_OF > + if (!dn) > + return -ENODEV; Checking !dn is done in of_property_read_u32, so you don't need to duplicate > + > + ret = of_property_read_u32(dn, "hwlock-base-id", &val); > + if (!ret) > + ret = val; > +#endif > + > + return ret; > +} > +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 > + * > + * This is an OF helper function that can be called by the underlying > + * platform-specific implementations, to retrieve the number of locks > + * present within a hwspinlock device instance. > + * > + * Returns a positive number of locks on success, -ENODEV on generic > + * failure or an appropriate error code as returned by the OF layer > + */ > +int of_hwspin_lock_get_num_locks(struct device_node *dn) > +{ > + unsigned int val; > + int ret = -ENODEV; > + > +#ifdef CONFIG_OF > + if (!dn) > + return -ENODEV; Checking !dn is done in of_property_read_u32, so you don't need to duplicate > + > + ret = of_property_read_u32(dn, "hwlock-num-locks", &val); > + if (!ret) > + ret = val ? val : -ENODEV; > +#endif > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(of_hwspin_lock_get_num_locks); > + > +/** > * hwspin_lock_register() - register a new hw spinlock device > * @bank: the hwspinlock device, which usually provides numerous hw locks > * @dev: the backing device > diff --git a/include/linux/hwspinlock.h b/include/linux/hwspinlock.h > index 3343298..1f6a5b8 100644 > --- a/include/linux/hwspinlock.h > +++ b/include/linux/hwspinlock.h > @@ -1,7 +1,7 @@ > /* > * Hardware spinlock public header > * > - * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com > + * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com > * > * Contact: Ohad Ben-Cohen > * > @@ -26,6 +26,7 @@ > #define HWLOCK_IRQ 0x02 /* Disable interrupts, don't save state */ > > struct device; > +struct device_node; > struct hwspinlock; > struct hwspinlock_device; > struct hwspinlock_ops; > @@ -60,6 +61,8 @@ struct hwspinlock_pdata { > > #if defined(CONFIG_HWSPINLOCK) || defined(CONFIG_HWSPINLOCK_MODULE) > > +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); > int hwspin_lock_unregister(struct hwspinlock_device *bank); > @@ -80,9 +83,9 @@ void __hwspin_unlock(struct hwspinlock *, int, unsigned long *); > * code path get compiled away. This way, if CONFIG_HWSPINLOCK is not > * required on a given setup, users will still work. > * > - * The only exception is hwspin_lock_register/hwspin_lock_unregister, with which > - * we _do_ want users to fail (no point in registering hwspinlock instances if > - * the framework is not available). > + * The only exception is hwspin_lock_register/hwspin_lock_unregister and > + * associated OF helpers, with which we _do_ want users to fail (no point > + * in registering hwspinlock instances if the framework is not available). > * > * Note: ERR_PTR(-ENODEV) will still be considered a success for NULL-checking > * users. Others, which care, can still check this with IS_ERR. > -- > 1.8.3.3 > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Employee of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/