Messages in this thread Patch in this message | | | Date | Thu, 13 Apr 2023 08:29:08 +0200 | From | Herve Codina <> | Subject | Re: [RFC PATCH 2/4] phy: Extend API to support 'status' get and notification |
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Hi Vinod,
On Wed, 12 Apr 2023 22:18:44 +0530 Vinod Koul <vkoul@kernel.org> wrote:
> On 23-03-23, 11:31, Herve Codina wrote: > > The PHY API provides functions to control and pass information from the > > PHY consumer to the PHY provider. > > There is no way for the consumer to get direct information from the PHY > > or be notified by the PHY. > > > > To fill this hole, two API function are provided: > > > > - phy_get_status() > > This function can be used to get a "status" from the PHY. It is built > > as the same ways as the configure() function. The status information > > present in the status retrieved depends on the PHY's phy_mode. > > This allows to get a "status" depending on the kind of PHY. > > what does 'status' mean and communicate to used? How does having this > help?
'status' can be some information that the PHY can provide to the consumer. The existing API does not provide a generic way to get some information from the PHY and 'status' with phy_get_status() provides this generic way. Its exact meaning depends on the kind of PHY. For the PHY_MODE_BASIC, introduced in this series, 'status' contains information related to the link state. And so, the consumer using a PHY_MODE_BASIC PHY can retreive the link state getting the 'status' from the PHY.
The patch 3 in this RFC details a consumer usage. An HDLC driver uses a PHY_MODE_BASIC PHY status to know the PHY link state and calls netif_carrier_{on,off}() accordingly.
Best regards, Hervé
> > > > > - phy_atomic_notifier_(un)register() > > These functions can be used to register/unregister an atomic notifier > > block. The event available at this time is the PHY_EVENT_STATUS status > > event which purpose is to signal some changes in the status available > > using phy_get_status(). > > > > An new kind of PHY is added: PHY_MODE_BASIC. > > This new kind of PHY represents a basic PHY offering a basic status This > > status contains a link state indication. > > With the new API, a link state indication can be retrieve using > > phy_get_status() and link state changes can be notified. > > > > Signed-off-by: Herve Codina <herve.codina@bootlin.com> > > --- > > drivers/phy/phy-core.c | 88 ++++++++++++++++++++++++++++++++++ > > include/linux/phy/phy-basic.h | 27 +++++++++++ > > include/linux/phy/phy.h | 89 ++++++++++++++++++++++++++++++++++- > > 3 files changed, 203 insertions(+), 1 deletion(-) > > create mode 100644 include/linux/phy/phy-basic.h > > > > diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c > > index 9951efc03eaa..c7b568b99dce 100644 > > --- a/drivers/phy/phy-core.c > > +++ b/drivers/phy/phy-core.c > > @@ -551,6 +551,94 @@ int phy_validate(struct phy *phy, enum phy_mode mode, int submode, > > } > > EXPORT_SYMBOL_GPL(phy_validate); > > > > +/** > > + * phy_get_status() - Gets the phy status > > + * @phy: the phy returned by phy_get() > > + * @status: the status to retrieve > > + * > > + * Used to get the PHY status. phy_init() must have been called > > + * on the phy. The status will be retrieved from the current phy mode, > > + * that can be changed using phy_set_mode(). > > + * > > + * Return: %0 if successful, a negative error code otherwise > > + */ > > +int phy_get_status(struct phy *phy, union phy_status *status) > > +{ > > + int ret; > > + > > + if (!phy) > > + return -EINVAL; > > + > > + if (!phy->ops->get_status) > > + return -EOPNOTSUPP; > > + > > + mutex_lock(&phy->mutex); > > + ret = phy->ops->get_status(phy, status); > > + mutex_unlock(&phy->mutex); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(phy_get_status); > > + > > +/** > > + * phy_atomic_notifier_register() - Registers an atomic notifier > > + * @phy: the phy returned by phy_get() > > + * @nb: the notifier block to register > > + * > > + * Used to register a notifier block on PHY events. phy_init() must have > > + * been called on the phy. > > + * The notifier function given in the notifier_block must not sleep. > > + * The available PHY events are present in enum phy_events > > + * > > + * Return: %0 if successful, a negative error code otherwise > > + */ > > +int phy_atomic_notifier_register(struct phy *phy, struct notifier_block *nb) > > +{ > > + int ret; > > + > > + if (!phy) > > + return -EINVAL; > > + > > + if (!phy->ops->atomic_notifier_register || > > + !phy->ops->atomic_notifier_unregister) > > + return -EOPNOTSUPP; > > + > > + mutex_lock(&phy->mutex); > > + ret = phy->ops->atomic_notifier_register(phy, nb); > > + mutex_unlock(&phy->mutex); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(phy_atomic_notifier_register); > > + > > +/** > > + * phy_atomic_notifier_unregister() - Unregisters an atomic notifier > > + * @phy: the phy returned by phy_get() > > + * @nb: the notifier block to unregister > > + * > > + * Used to unregister a notifier block. phy_init() must have > > + * been called on the phy. > > + * > > + * Return: %0 if successful, a negative error code otherwise > > + */ > > +int phy_atomic_notifier_unregister(struct phy *phy, struct notifier_block *nb) > > +{ > > + int ret; > > + > > + if (!phy) > > + return -EINVAL; > > + > > + if (!phy->ops->atomic_notifier_unregister) > > + return -EOPNOTSUPP; > > + > > + mutex_lock(&phy->mutex); > > + ret = phy->ops->atomic_notifier_unregister(phy, nb); > > + mutex_unlock(&phy->mutex); > > + > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(phy_atomic_notifier_unregister); > > + > > /** > > * _of_phy_get() - lookup and obtain a reference to a phy by phandle > > * @np: device_node for which to get the phy > > diff --git a/include/linux/phy/phy-basic.h b/include/linux/phy/phy-basic.h > > new file mode 100644 > > index 000000000000..95668c610c78 > > --- /dev/null > > +++ b/include/linux/phy/phy-basic.h > > @@ -0,0 +1,27 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Copyright 2023 CS GROUP France > > + * > > + * Author: Herve Codina <herve.codina@bootlin.com> > > + */ > > + > > +#ifndef __PHY_BASIC_H_ > > +#define __PHY_BASIC_H_ > > + > > +#include <linux/types.h> > > + > > +/** > > + * struct phy_status_basic - Basic PHY status > > + * > > + * This structure is used to represent the status of a Basic phy. > > + */ > > +struct phy_status_basic { > > + /** > > + * @link_state: > > + * > > + * Link state. true, the link is on, false, the link is off. > > + */ > > + bool link_is_on; > > +}; > > + > > +#endif /* __PHY_DP_H_ */ > > diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h > > index 3a570bc59fc7..40370d41012b 100644 > > --- a/include/linux/phy/phy.h > > +++ b/include/linux/phy/phy.h > > @@ -16,6 +16,7 @@ > > #include <linux/pm_runtime.h> > > #include <linux/regulator/consumer.h> > > > > +#include <linux/phy/phy-basic.h> > > #include <linux/phy/phy-dp.h> > > #include <linux/phy/phy-lvds.h> > > #include <linux/phy/phy-mipi-dphy.h> > > @@ -42,7 +43,8 @@ enum phy_mode { > > PHY_MODE_MIPI_DPHY, > > PHY_MODE_SATA, > > PHY_MODE_LVDS, > > - PHY_MODE_DP > > + PHY_MODE_DP, > > + PHY_MODE_BASIC, > > }; > > > > enum phy_media { > > @@ -67,6 +69,22 @@ union phy_configure_opts { > > struct phy_configure_opts_lvds lvds; > > }; > > > > +/** > > + * union phy_status - Opaque generic phy status > > + * > > + * @basic: Status availbale phys supporting the Basic phy mode. > > + */ > > +union phy_status { > > + struct phy_status_basic basic; > > +}; > > + > > +/** > > + * phy_event - event available for notification > > + */ > > +enum phy_event { > > + PHY_EVENT_STATUS, /* Event notified on phy_status changes */ > > +}; > > + > > /** > > * struct phy_ops - set of function pointers for performing phy operations > > * @init: operation to be performed for initializing phy > > @@ -120,6 +138,45 @@ struct phy_ops { > > */ > > int (*validate)(struct phy *phy, enum phy_mode mode, int submode, > > union phy_configure_opts *opts); > > + > > + /** > > + * @get_status: > > + * > > + * Optional. > > + * > > + * Used to get the PHY status. phy_init() must have > > + * been called on the phy. > > + * > > + * Returns: 0 if successful, an negative error code otherwise > > + */ > > + int (*get_status)(struct phy *phy, union phy_status *status); > > + > > + /** > > + * @atomic_notifier_register: > > + * > > + * Optional. > > + * > > + * Used to register a notifier block on PHY events. phy_init() must have > > + * been called on the phy. > > + * The notifier function given in the notifier_block must not sleep. > > + * The available PHY events are present in enum phy_events > > + * > > + * Returns: 0 if successful, an negative error code otherwise > > + */ > > + int (*atomic_notifier_register)(struct phy *phy, struct notifier_block *nb); > > + > > + /** > > + * @atomic_notifier_unregister: > > + * > > + * Mandatoty if @atomic_notifier_register is set. > > + * > > + * Used to unregister a notifier block on PHY events. phy_init() must have > > + * been called on the phy. > > + * > > + * Returns: 0 if successful, an negative error code otherwise > > + */ > > + int (*atomic_notifier_unregister)(struct phy *phy, struct notifier_block *nb); > > + > > int (*reset)(struct phy *phy); > > int (*calibrate)(struct phy *phy); > > void (*release)(struct phy *phy); > > @@ -234,6 +291,10 @@ int phy_set_speed(struct phy *phy, int speed); > > int phy_configure(struct phy *phy, union phy_configure_opts *opts); > > int phy_validate(struct phy *phy, enum phy_mode mode, int submode, > > union phy_configure_opts *opts); > > +int phy_get_status(struct phy *phy, union phy_status *status); > > +int phy_atomic_notifier_register(struct phy *phy, struct notifier_block *nb); > > +int phy_atomic_notifier_unregister(struct phy *phy, struct notifier_block *nb); > > + > > > > static inline enum phy_mode phy_get_mode(struct phy *phy) > > { > > @@ -412,6 +473,32 @@ static inline int phy_validate(struct phy *phy, enum phy_mode mode, int submode, > > return -ENOSYS; > > } > > > > +static inline int phy_get_status(struct phy *phy, union phy_status *status) > > +{ > > + if (!phy) > > + return 0; > > + > > + return -ENOSYS; > > +} > > + > > +static inline int phy_atomic_notifier_register(struct phy *phy, > > + struct notifier_block *nb) > > +{ > > + if (!phy) > > + return 0; > > + > > + return -ENOSYS; > > +} > > + > > +static inline int phy_atomic_notifier_unregister(struct phy *phy, > > + struct notifier_block *nb) > > +{ > > + if (!phy) > > + return 0; > > + > > + return -ENOSYS; > > +} > > + > > static inline int phy_get_bus_width(struct phy *phy) > > { > > return -ENOSYS; > > -- > > 2.39.2 > > > > > > -- > > linux-phy mailing list > > linux-phy@lists.infradead.org > > https://lists.infradead.org/mailman/listinfo/linux-phy >
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