| Message ID | 1606717202-4206-1-git-send-email-pthombar@cadence.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | I3C mastership handover support | expand |
On 30/11/2020 07:20:02+0100, Parshuram Thombare wrote: > Added support to acquire I3C bus through sysfs interface. > > Signed-off-by: Parshuram Thombare <pthombar@cadence.com> > --- > drivers/i3c/master.c | 18 ++++++++++++++++++ > 1 files changed, 18 insertions(+), 0 deletions(-) > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c > index c01ba00..beb7495 100644 > --- a/drivers/i3c/master.c > +++ b/drivers/i3c/master.c > @@ -581,6 +581,23 @@ static ssize_t i2c_scl_frequency_show(struct device *dev, > } > static DEVICE_ATTR_RO(i2c_scl_frequency); > > +static ssize_t i3c_acquire_bus_store(struct device *dev, > + struct device_attribute *attr, > + const char *buf, size_t count) > +{ > + struct i3c_master_controller *master = dev_to_i3cmaster(dev); > + int ret; > + > + i3c_bus_normaluse_lock(&master->bus); > + ret = i3c_master_acquire_bus(master); > + i3c_bus_normaluse_unlock(&master->bus); > + if (!ret) > + i3c_master_enable_mr_events(master); > + > + return ret ?: count; > +} > +static DEVICE_ATTR_WO(i3c_acquire_bus); > + I'm wondering whether we should allow userspace to actually control that. Shouldn't we simply request mastership when a driver needs to talk to a device on the bus? Is it really useful to have that until there is an i3c-dev userspace interface? > static struct attribute *i3c_masterdev_attrs[] = { > &dev_attr_mode.attr, > &dev_attr_current_master.attr, > @@ -591,6 +608,7 @@ static ssize_t i2c_scl_frequency_show(struct device *dev, > &dev_attr_pid.attr, > &dev_attr_dynamic_address.attr, > &dev_attr_hdrcap.attr, > + &dev_attr_i3c_acquire_bus.attr, > NULL, > }; > ATTRIBUTE_GROUPS(i3c_masterdev); > -- > 1.7.1 >
>I'm wondering whether we should allow userspace to actually control >that. Shouldn't we simply request mastership when a driver needs to talk >to a device on the bus? Is it really useful to have that until there is >an i3c-dev userspace interface? Yes, for now it is useful for nothing more than triggering mastership request from user space. It can be dropped and added later if needed for i3c-dev user space interface.
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index c01ba00..beb7495 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -581,6 +581,23 @@ static ssize_t i2c_scl_frequency_show(struct device *dev, } static DEVICE_ATTR_RO(i2c_scl_frequency); +static ssize_t i3c_acquire_bus_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct i3c_master_controller *master = dev_to_i3cmaster(dev); + int ret; + + i3c_bus_normaluse_lock(&master->bus); + ret = i3c_master_acquire_bus(master); + i3c_bus_normaluse_unlock(&master->bus); + if (!ret) + i3c_master_enable_mr_events(master); + + return ret ?: count; +} +static DEVICE_ATTR_WO(i3c_acquire_bus); + static struct attribute *i3c_masterdev_attrs[] = { &dev_attr_mode.attr, &dev_attr_current_master.attr, @@ -591,6 +608,7 @@ static ssize_t i2c_scl_frequency_show(struct device *dev, &dev_attr_pid.attr, &dev_attr_dynamic_address.attr, &dev_attr_hdrcap.attr, + &dev_attr_i3c_acquire_bus.attr, NULL, }; ATTRIBUTE_GROUPS(i3c_masterdev);
Added support to acquire I3C bus through sysfs interface. Signed-off-by: Parshuram Thombare <pthombar@cadence.com> --- drivers/i3c/master.c | 18 ++++++++++++++++++ 1 files changed, 18 insertions(+), 0 deletions(-)