From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755608AbcH1QG2 (ORCPT ); Sun, 28 Aug 2016 12:06:28 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:36260 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752371AbcH1QG0 (ORCPT ); Sun, 28 Aug 2016 12:06:26 -0400 Date: Sun, 28 Aug 2016 18:06:21 +0200 From: Daniel Vetter To: Peter Rosin Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, dri-devel@lists.freedesktop.org, Wolfram Sang Subject: Re: [PATCH v2] i2c: move locking operations to their own struct Message-ID: <20160828160621.GX10980@phenom.ffwll.local> Mail-Followup-To: Peter Rosin , linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, dri-devel@lists.freedesktop.org, Wolfram Sang References: <1472159221-10807-1-git-send-email-peda@axentia.se> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1472159221-10807-1-git-send-email-peda@axentia.se> X-Operating-System: Linux phenom 4.6.0-1-amd64 User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 25, 2016 at 11:07:01PM +0200, Peter Rosin wrote: > This makes it trivial to constify them, so do that. > > Signed-off-by: Peter Rosin Acked-by: Daniel Vetter Feel free to merge through i2c tree. -Daniel > --- > drivers/gpu/drm/drm_dp_helper.c | 10 +++++++--- > drivers/i2c/i2c-core.c | 13 ++++++++----- > drivers/i2c/i2c-mux.c | 25 ++++++++++++++++--------- > include/linux/i2c.h | 25 ++++++++++++++++++------- > 4 files changed, 49 insertions(+), 24 deletions(-) > > Changes since v1: > > - Also fix the user in drivers/gpu (only compile-tested, but > it's simple enough...) > > This takes care of the 0-day splat reported in: > http://marc.info/?l=linux-i2c&m=147215193023544&w=2 > > Cheers, > Peter > > diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c > index eae5ef963cb7..2bd064493ae7 100644 > --- a/drivers/gpu/drm/drm_dp_helper.c > +++ b/drivers/gpu/drm/drm_dp_helper.c > @@ -790,6 +790,12 @@ static void unlock_bus(struct i2c_adapter *i2c, unsigned int flags) > mutex_unlock(&i2c_to_aux(i2c)->hw_mutex); > } > > +static const struct i2c_lock_operations drm_dp_i2c_lock_ops = { > + .lock_bus = lock_bus, > + .trylock_bus = trylock_bus, > + .unlock_bus = unlock_bus, > +}; > + > /** > * drm_dp_aux_init() - minimally initialise an aux channel > * @aux: DisplayPort AUX channel > @@ -807,9 +813,7 @@ void drm_dp_aux_init(struct drm_dp_aux *aux) > aux->ddc.algo_data = aux; > aux->ddc.retries = 3; > > - aux->ddc.lock_bus = lock_bus; > - aux->ddc.trylock_bus = trylock_bus; > - aux->ddc.unlock_bus = unlock_bus; > + aux->ddc.lock_ops = &drm_dp_i2c_lock_ops; > } > EXPORT_SYMBOL(drm_dp_aux_init); > > diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c > index 56e50ca905ba..0bdda24a10b2 100644 > --- a/drivers/i2c/i2c-core.c > +++ b/drivers/i2c/i2c-core.c > @@ -1691,6 +1691,12 @@ static int __process_new_adapter(struct device_driver *d, void *data) > return i2c_do_add_adapter(to_i2c_driver(d), data); > } > > +static const struct i2c_lock_operations i2c_adapter_lock_ops = { > + .lock_bus = i2c_adapter_lock_bus, > + .trylock_bus = i2c_adapter_trylock_bus, > + .unlock_bus = i2c_adapter_unlock_bus, > +}; > + > static int i2c_register_adapter(struct i2c_adapter *adap) > { > int res = -EINVAL; > @@ -1710,11 +1716,8 @@ static int i2c_register_adapter(struct i2c_adapter *adap) > goto out_list; > } > > - if (!adap->lock_bus) { > - adap->lock_bus = i2c_adapter_lock_bus; > - adap->trylock_bus = i2c_adapter_trylock_bus; > - adap->unlock_bus = i2c_adapter_unlock_bus; > - } > + if (!adap->lock_ops) > + adap->lock_ops = &i2c_adapter_lock_ops; > > rt_mutex_init(&adap->bus_lock); > rt_mutex_init(&adap->mux_lock); > diff --git a/drivers/i2c/i2c-mux.c b/drivers/i2c/i2c-mux.c > index 764f195795e4..14741ff31041 100644 > --- a/drivers/i2c/i2c-mux.c > +++ b/drivers/i2c/i2c-mux.c > @@ -263,6 +263,18 @@ struct i2c_mux_core *i2c_mux_alloc(struct i2c_adapter *parent, > } > EXPORT_SYMBOL_GPL(i2c_mux_alloc); > > +static const struct i2c_lock_operations i2c_mux_lock_ops = { > + .lock_bus = i2c_mux_lock_bus, > + .trylock_bus = i2c_mux_trylock_bus, > + .unlock_bus = i2c_mux_unlock_bus, > +}; > + > +static const struct i2c_lock_operations i2c_parent_lock_ops = { > + .lock_bus = i2c_parent_lock_bus, > + .trylock_bus = i2c_parent_trylock_bus, > + .unlock_bus = i2c_parent_unlock_bus, > +}; > + > int i2c_mux_add_adapter(struct i2c_mux_core *muxc, > u32 force_nr, u32 chan_id, > unsigned int class) > @@ -312,15 +324,10 @@ int i2c_mux_add_adapter(struct i2c_mux_core *muxc, > priv->adap.retries = parent->retries; > priv->adap.timeout = parent->timeout; > priv->adap.quirks = parent->quirks; > - if (muxc->mux_locked) { > - priv->adap.lock_bus = i2c_mux_lock_bus; > - priv->adap.trylock_bus = i2c_mux_trylock_bus; > - priv->adap.unlock_bus = i2c_mux_unlock_bus; > - } else { > - priv->adap.lock_bus = i2c_parent_lock_bus; > - priv->adap.trylock_bus = i2c_parent_trylock_bus; > - priv->adap.unlock_bus = i2c_parent_unlock_bus; > - } > + if (muxc->mux_locked) > + priv->adap.lock_ops = &i2c_mux_lock_ops; > + else > + priv->adap.lock_ops = &i2c_parent_lock_ops; > > /* Sanity check on class */ > if (i2c_mux_parent_classes(parent) & class) > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > index c1f60a345db7..616f67635734 100644 > --- a/include/linux/i2c.h > +++ b/include/linux/i2c.h > @@ -427,6 +427,20 @@ struct i2c_algorithm { > }; > > /** > + * struct i2c_lock_operations - represent I2C locking operations > + * @lock_bus: Get exclusive access to an I2C bus segment > + * @trylock_bus: Try to get exclusive access to an I2C bus segment > + * @unlock_bus: Release exclusive access to an I2C bus segment > + * > + * The main operations are wrapped by i2c_lock_bus and i2c_unlock_bus. > + */ > +struct i2c_lock_operations { > + void (*lock_bus)(struct i2c_adapter *, unsigned int flags); > + int (*trylock_bus)(struct i2c_adapter *, unsigned int flags); > + void (*unlock_bus)(struct i2c_adapter *, unsigned int flags); > +}; > + > +/** > * struct i2c_timings - I2C timing information > * @bus_freq_hz: the bus frequency in Hz > * @scl_rise_ns: time SCL signal takes to rise in ns; t(r) in the I2C specification > @@ -536,6 +550,7 @@ struct i2c_adapter { > void *algo_data; > > /* data fields that are valid for all devices */ > + const struct i2c_lock_operations *lock_ops; > struct rt_mutex bus_lock; > struct rt_mutex mux_lock; > > @@ -552,10 +567,6 @@ struct i2c_adapter { > > struct i2c_bus_recovery_info *bus_recovery_info; > const struct i2c_adapter_quirks *quirks; > - > - void (*lock_bus)(struct i2c_adapter *, unsigned int flags); > - int (*trylock_bus)(struct i2c_adapter *, unsigned int flags); > - void (*unlock_bus)(struct i2c_adapter *, unsigned int flags); > }; > #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev) > > @@ -597,7 +608,7 @@ int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)); > static inline void > i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) > { > - adapter->lock_bus(adapter, flags); > + adapter->lock_ops->lock_bus(adapter, flags); > } > > /** > @@ -611,7 +622,7 @@ i2c_lock_bus(struct i2c_adapter *adapter, unsigned int flags) > static inline int > i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) > { > - return adapter->trylock_bus(adapter, flags); > + return adapter->lock_ops->trylock_bus(adapter, flags); > } > > /** > @@ -623,7 +634,7 @@ i2c_trylock_bus(struct i2c_adapter *adapter, unsigned int flags) > static inline void > i2c_unlock_bus(struct i2c_adapter *adapter, unsigned int flags) > { > - adapter->unlock_bus(adapter, flags); > + adapter->lock_ops->unlock_bus(adapter, flags); > } > > static inline void > -- > 2.1.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch