Hi, On Wed, Nov 04, 2020 at 11:16:31AM -0500, Thara Gopinath wrote: > Hi Cristian, > > On 10/28/20 4:29 PM, Cristian Marussi wrote: > > Expose a new generic get/put protocols API based on protocol handles; > > provide also a devres managed version also for notifications. > > minor nit.. Maybe yous should reword this! Kind of confusing to understand! > > Also, if it was me, I will separate the notifications and get/put hooks > into two separate patches. Not an issue though if you want to keep it > in the same patch.
You're right I have to reword the commit message, and I'll review the possibility of a further split, even though many parts of this series are tightly bound together given the kind of changes so sometimes to avoid breaking bisectability I had to push painfully long patches (like 6/8 :< )...but maybe I've got it wrong and this is not the case here. > > > All SCMI drivers still keep using the old handle based interface. > > > > Signed-off-by: Cristian Marussi <[email protected]> > > --- > > drivers/firmware/arm_scmi/driver.c | 126 +++++++++++++++++++++++++++++ > > drivers/firmware/arm_scmi/notify.c | 123 ++++++++++++++++++++++++++++ > > include/linux/scmi_protocol.h | 34 +++++++- > > 3 files changed, 282 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/firmware/arm_scmi/driver.c > > b/drivers/firmware/arm_scmi/driver.c > > index 8ca04acb6abb..4d86aafbf465 100644 > > --- a/drivers/firmware/arm_scmi/driver.c > > +++ b/drivers/firmware/arm_scmi/driver.c > > @@ -15,6 +15,7 @@ > > */ > > #include <linux/bitmap.h> > > +#include <linux/device.h> > > #include <linux/export.h> > > #include <linux/idr.h> > > #include <linux/io.h> > > @@ -728,6 +729,38 @@ void scmi_release_protocol(struct scmi_handle *handle, > > u8 protocol_id) > > mutex_unlock(&info->protocols_mtx); > > } > > +/** > > + * scmi_get_protocol_operations - Get protocol operations > > + * @handle: A reference to the SCMI platform instance. > > + * @protocol_id: The protocol being requested. > > + * @ph: A pointer reference used to pass back the associated protocol > > handle. > > + * > > + * Get hold of a protocol accounting for its usage, eventually triggering > > its > > + * initialization, and returning the protocol specific operations and > > related > > + * protocol handle which will be used as first argument in most of the > > protocols > > + * operations methods. > > + * > > + * Return: A reference to the requested protocol operations or error. > > + * Must be checked for errors by caller. > > + */ > > +static const void __must_check * > > +scmi_get_protocol_operations(struct scmi_handle *handle, u8 protocol_id, > > + struct scmi_protocol_handle **ph) > > +{ > > + struct scmi_protocol_instance *pi; > > + > > + if (!ph) > > + return ERR_PTR(-EINVAL); > > + > > + pi = scmi_get_protocol_instance(handle, protocol_id); > > + if (IS_ERR(pi)) > > + return pi; > > + > > + *ph = &pi->ph; > > + > > + return pi->proto->ops; > > +} > > + > > void scmi_setup_protocol_implemented(const struct scmi_handle *handle, > > u8 *prot_imp) > > { > > @@ -751,6 +784,95 @@ scmi_is_protocol_implemented(const struct scmi_handle > > *handle, u8 prot_id) > > return false; > > } > > +struct scmi_protocol_devres { > > + struct scmi_handle *handle; > > + u8 protocol_id; > > +}; > > + > > +static void scmi_devm_release_protocol(struct device *dev, void *res) > > +{ > > + struct scmi_protocol_devres *dres = res; > > + > > + scmi_release_protocol(dres->handle, dres->protocol_id); > > +} > > + > > +/** > > + * scmi_devm_get_protocol_ops - Devres managed get protocol operations > > + * @sdev: A reference to an scmi_device whose embedded struct device is to > > + * be used for devres accounting. > > + * @protocol_id: The protocol being requested. > > + * @ph: A pointer reference used to pass back the associated protocol > > handle. > > + * > > + * Get hold of a protocol accounting for its usage, eventually triggering > > its > > + * initialization, and returning the protocol specific operations and > > related > > + * protocol handle which will be used as first argument in most of the > > + * protocols operations methods. > > + * Being a devres based managed method, protocol hold will be automatically > > + * released, and possibly de-initialized on last user, once the SCMI driver > > + * owning the scmi_device is unbound from it. > > + * > > + * Return: A reference to the requested protocol operations or error. > > + * Must be checked for errors by caller. > > + */ > > +static const void __must_check * > > +scmi_devm_get_protocol_ops(struct scmi_device *sdev, u8 protocol_id, > > + struct scmi_protocol_handle **ph) > > +{ > > + struct scmi_protocol_instance *pi; > > + struct scmi_protocol_devres *dres; > > + struct scmi_handle *handle = sdev->handle; > > + > > + if (!ph) > > + return ERR_PTR(-EINVAL); > > + > > + dres = devres_alloc(scmi_devm_release_protocol, > > + sizeof(*dres), GFP_KERNEL); > > + if (!dres) > > + return ERR_PTR(-ENOMEM); > > + > > + pi = scmi_get_protocol_instance(handle, protocol_id); > > + if (IS_ERR(pi)) { > > + devres_free(dres); > > + return pi; > > + } > > + > > + dres->handle = handle; > > + dres->protocol_id = protocol_id; > > + devres_add(&sdev->dev, dres); > > + > > + *ph = &pi->ph; > > + > > + return pi->proto->ops; > > +} > > + > > +static int scmi_devm_protocol_match(struct device *dev, void *res, void > > *data) > > +{ > > + struct scmi_protocol_devres *dres = res; > > + > > + if (WARN_ON(!dres || !data)) > > + return 0; > > + > > + return dres->protocol_id == *((u8 *)data); > > +} > > + > > +/** > > + * scmi_devm_put_protocol_ops - Devres managed put protocol operations > > + * @sdev: A reference to an scmi_device whose embedded struct device is to > > + * be used for devres accounting. > > + * @protocol_id: The protocol being requested. > > + * > > + * Explicitly release a protocol hold previously obtained calling the above > > + * @scmi_devm_get_protocol_ops. > > + */ > > +static void scmi_devm_put_protocol_ops(struct scmi_device *sdev, u8 > > protocol_id) > > +{ > > + int ret; > > + > > + ret = devres_release(&sdev->dev, scmi_devm_release_protocol, > > + scmi_devm_protocol_match, &protocol_id); > > + WARN_ON(ret); > > +} > > + > > /** > > * scmi_handle_get() - Get the SCMI handle for a device > > * > > @@ -1004,6 +1126,10 @@ static int scmi_probe(struct platform_device *pdev) > > handle = &info->handle; > > handle->dev = info->dev; > > handle->version = &info->version; > > + handle->devm_get_ops = scmi_devm_get_protocol_ops; > > + handle->devm_put_ops = scmi_devm_put_protocol_ops; > > + handle->get_ops = scmi_get_protocol_operations; > > + handle->put_ops = scmi_release_protocol; > > Why do you need a dev_res version and a non dev_res version? I checked > patch 6 where you convert the drivers to use these hooks and all of them > are using the dev res apis. > Yes indeed, I wanted to drop the non devm_ version, but I was not sure if for completeness I should have instead not provided...So I left it to have it discussed on the list...I was hoping to be told to remove those non devres :D Also because in fact any current or future SCMI driver (that are the only possible users of this interface) will certainly have an scmi_dev to use with devm_() methods. Probably the same is true for notify_ops, I could stick with the new devres managed versions. > > ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE); > > if (ret) > > diff --git a/drivers/firmware/arm_scmi/notify.c > > b/drivers/firmware/arm_scmi/notify.c > > index eae58b2a92cc..64d43e425644 100644 > > --- a/drivers/firmware/arm_scmi/notify.c > > +++ b/drivers/firmware/arm_scmi/notify.c > > @@ -1370,6 +1370,127 @@ static int scmi_unregister_notifier(const struct > > scmi_handle *handle, > > return 0; > > } > > +struct scmi_notifier_devres { > > + const struct scmi_handle *handle; > > + u8 proto_id; > > + u8 evt_id; > > + u32 __src_id; > > + u32 *src_id; > > Instead of maintaining two separate pointers for src id, > why not define a bool, something like is_src_id_valid? > Should simply this a bit and also don't have to maintain two 32 bit > pointers. What do you think? > Yes, I did not like so much this trick above, I'll review in V3. > > + struct notifier_block *nb; > > +}; > > + > > +static void scmi_devm_release_notifier(struct device *dev, void *res) > > +{ > > + struct scmi_notifier_devres *dres = res; > > + > > + scmi_unregister_notifier(dres->handle, dres->proto_id, dres->evt_id, > > + dres->src_id, dres->nb); > > +} > > + > > +/** > > + * scmi_devm_register_notifier() - Managed registration of a > > notifier_block > > + * for an event > > + * @sdev: A reference to an scmi_device whose embedded struct device is to > > + * be used for devres accounting. > > + * @proto_id: Protocol ID > > + * @evt_id: Event ID > > + * @src_id: Source ID, when NULL register for events coming form ALL > > possible > > + * sources > > + * @nb: A standard notifier block to register for the specified event > > + * > > + * Generic devres managed helper to register a notifier_block against a > > + * protocol event. > > + */ > > +static int scmi_devm_register_notifier(struct scmi_device *sdev, > > + u8 proto_id, u8 evt_id, u32 *src_id, > > + struct notifier_block *nb) > > +{ > > + int ret; > > + struct scmi_notifier_devres *dres; > > + > > + dres = devres_alloc(scmi_devm_release_notifier, > > + sizeof(*dres), GFP_KERNEL); > > + if (!dres) > > + return -ENOMEM; > > + > > + ret = scmi_register_notifier(sdev->handle, proto_id, > > + evt_id, src_id, nb); > > + if (ret) { > > + devres_free(dres); > > + return ret; > > + } > > + > > + dres->handle = sdev->handle; > > + dres->proto_id = proto_id; > > + dres->evt_id = evt_id; > > + dres->nb = nb; > > + if (src_id) { > > + dres->__src_id = *src_id; > > + dres->src_id = &dres->__src_id; > > + } else { > > + dres->src_id = NULL; > > + } > > + devres_add(&sdev->dev, dres); > > + > > + return ret; > > +} > > + > > +static int scmi_devm_notifier_match(struct device *dev, void *res, void > > *data) > > +{ > > + struct scmi_notifier_devres *dres = res; > > + struct scmi_notifier_devres *xres = data; > > + > > + if (WARN_ON(!dres || !xres)) > > + return 0; > > + > > + return dres->proto_id == xres->proto_id && > > + dres->evt_id == xres->evt_id && > > + dres->nb == xres->nb && > > Does the nb have to be compared as well ? > So the notify_ops API allows you to register multiple different callbacks for exactly the same event tuple (proto_id, evt_id, src_id), and even though on driver detach you'll automatically just unregister all the notifications registered for the specific scmi_dev, you should be able to explicitly devm_unregister() just a very specific callback if you want. > > + ((!dres->src_id && !xres->src_id) || > > + (dres->src_id && xres->src_id && > > + dres->__src_id == xres->__src_id)); > > > -- > Warm Regards > Thara Cheers Cristian
