Hi Vinod,

Thanks for your review feedback.

On Wed, 20 Aug 2025 at 17:34, Vinod Koul [off-list ref] wrote:

On 13-08-25, 16:00, Peter Griffin wrote:

quoted

Add a new phy_notify_state() api that notifies and configures a phy for a
given state transition.

This is intended to be by phy drivers which need to do some runtime

                    ^^^^^^^^^^
Missing 'used' possibly?

Yes your right, good spot, will fix.

quoted

configuration of parameters that can't be handled by phy_calibrate() or
phy_power_{on|off}().

The first usage of this API is in the Samsung UFS phy that needs to issue
some register writes when entering and exiting the hibernate link state.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
 drivers/phy/phy-core.c  | 25 +++++++++++++++++++++++++
 include/linux/phy/phy.h | 19 +++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 04a5a34e7a950ae94fae915673c25d476fc071c1..60be8af984bf06649ef00e695d0ed4ced597cdb9 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c

@@ -520,6 +520,31 @@ int phy_notify_disconnect(struct phy *phy, int port)
 }
 EXPORT_SYMBOL_GPL(phy_notify_disconnect);

+/**
+ * phy_notify_state() - phy state notification
+ * @phy: the PHY returned by phy_get()
+ * @state: the PHY state
+ *
+ * Notify the PHY of a state transition. Used to notify and
+ * configure the PHY accordingly.
+ *
+ * Returns: %0 if successful, a negative error code otherwise
+ */
+int phy_notify_state(struct phy *phy, union phy_notify state)
+{
+     int ret;
+
+     if (!phy || !phy->ops->notify_phystate)
+             return 0;
+
+     mutex_lock(&phy->mutex);
+     ret = phy->ops->notify_phystate(phy, state);
+     mutex_unlock(&phy->mutex);
+
+     return ret;
+}
+EXPORT_SYMBOL_GPL(phy_notify_state);
+
 /**
  * phy_configure() - Changes the phy parameters
  * @phy: the phy returned by phy_get()

diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index 13add0c2c40721fe9ca3f0350d13c035cd25af45..664d0864c3a5042949cb121e982368fe0a97827f 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h

@@ -53,6 +53,15 @@ enum phy_media {
      PHY_MEDIA_DAC,
 };

+enum phy_ufs_state {
+     PHY_UFS_HIBERN8_ENTER,
+     PHY_UFS_HIBERN8_EXIT,
+};
+
+union phy_notify {
+     enum phy_ufs_state ufs_state;
+};
+
 /**
  * union phy_configure_opts - Opaque generic phy configuration
  *

@@ -83,6 +92,7 @@ union phy_configure_opts {
  * @set_speed: set the speed of the phy (optional)
  * @reset: resetting the phy
  * @calibrate: calibrate the phy
+ * @notify_phystate: notify and configure the phy for a particular state
  * @release: ops to be performed while the consumer relinquishes the PHY
  * @owner: the module owner containing the ops
  */

@@ -132,6 +142,7 @@ struct phy_ops {
      int     (*connect)(struct phy *phy, int port);
      int     (*disconnect)(struct phy *phy, int port);

+     int     (*notify_phystate)(struct phy *phy, union phy_notify state);
      void    (*release)(struct phy *phy);
      struct module *owner;
 };

@@ -255,6 +266,7 @@ int phy_reset(struct phy *phy);
 int phy_calibrate(struct phy *phy);
 int phy_notify_connect(struct phy *phy, int port);
 int phy_notify_disconnect(struct phy *phy, int port);
+int phy_notify_state(struct phy *phy, union phy_notify state);
 static inline int phy_get_bus_width(struct phy *phy)
 {
      return phy->attrs.bus_width;

@@ -412,6 +424,13 @@ static inline int phy_notify_disconnect(struct phy *phy, int index)
      return -ENOSYS;
 }

+static inline int phy_notify_phystate(struct phy *phy, union phy_notify state)
+{
+     if (!phy)
+             return 0;
+     return -ENOSYS;

Should be -ENOSYS either way, right?

I initially thought the same, but I followed the pattern that is used
by many of the other phy API calls like phy_init/exit,
phy_power_on/off phy_calibrate, phy_notify_connect in
include/linux/phy/phy.h. I can update it if you like, but I was trying
to keep it consistent.

The only API I can see (that isn't a *phy_get* or *phy_create*) which
returns -ENOSYS unconditionally is phy_get_bus_width()

Thanks,

Peter