Add new callback operations for a dpll device:
- freq_monitor_get(..) - to obtain current state of frequency monitor
feature from dpll device,
- freq_monitor_set(..) - to allow feature configuration.
Add new callback operation for a dpll pin:
- actual_freq_get(..) - to obtain the actual (measured) frequency in Hz.
Obtain the feature state value using the get callback and provide it to
the user if the device driver implements callbacks. The actual_freq_get
pin callback is only invoked when the frequency monitor is enabled.
Execute the set callback upon user requests.
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
drivers/dpll/dpll_netlink.c | 90 +++++++++++++++++++++++++++++++++++++
include/linux/dpll.h | 12 +++++
2 files changed, 102 insertions(+)
diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 83cbd64abf5a4..6fe4ae38cff62 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -175,6 +175,26 @@ dpll_msg_add_phase_offset_monitor(struct sk_buff *msg, struct dpll_device *dpll,
return 0;
}
+static int
+dpll_msg_add_freq_monitor(struct sk_buff *msg, struct dpll_device *dpll,
+ struct netlink_ext_ack *extack)
+{
+ const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+ enum dpll_feature_state state;
+ int ret;
+
+ if (ops->freq_monitor_set && ops->freq_monitor_get) {
+ ret = ops->freq_monitor_get(dpll, dpll_priv(dpll),
+ &state, extack);
+ if (ret)
+ return ret;
+ if (nla_put_u32(msg, DPLL_A_FREQUENCY_MONITOR, state))
+ return -EMSGSIZE;
+ }
+
+ return 0;
+}
+
static int
dpll_msg_add_phase_offset_avg_factor(struct sk_buff *msg,
struct dpll_device *dpll,
@@ -400,6 +420,38 @@ static int dpll_msg_add_ffo(struct sk_buff *msg, struct dpll_pin *pin,
ffo);
}
+static int dpll_msg_add_actual_freq(struct sk_buff *msg, struct dpll_pin *pin,
+ struct dpll_pin_ref *ref,
+ struct netlink_ext_ack *extack)
+{
+ const struct dpll_device_ops *dev_ops = dpll_device_ops(ref->dpll);
+ const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
+ struct dpll_device *dpll = ref->dpll;
+ enum dpll_feature_state state;
+ u64 actual_freq;
+ int ret;
+
+ if (!ops->actual_freq_get)
+ return 0;
+ if (dev_ops->freq_monitor_get) {
+ ret = dev_ops->freq_monitor_get(dpll, dpll_priv(dpll),
+ &state, extack);
+ if (ret)
+ return ret;
+ if (state == DPLL_FEATURE_STATE_DISABLE)
+ return 0;
+ }
+ ret = ops->actual_freq_get(pin, dpll_pin_on_dpll_priv(dpll, pin),
+ dpll, dpll_priv(dpll), &actual_freq, extack);
+ if (ret)
+ return ret;
+ if (nla_put_64bit(msg, DPLL_A_PIN_ACTUAL_FREQUENCY,
+ sizeof(actual_freq), &actual_freq, DPLL_A_PIN_PAD))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
static int
dpll_msg_add_pin_freq(struct sk_buff *msg, struct dpll_pin *pin,
struct dpll_pin_ref *ref, struct netlink_ext_ack *extack)
@@ -670,6 +722,9 @@ dpll_cmd_pin_get_one(struct sk_buff *msg, struct dpll_pin *pin,
if (ret)
return ret;
ret = dpll_msg_add_ffo(msg, pin, ref, extack);
+ if (ret)
+ return ret;
+ ret = dpll_msg_add_actual_freq(msg, pin, ref, extack);
if (ret)
return ret;
ret = dpll_msg_add_pin_esync(msg, pin, ref, extack);
@@ -722,6 +777,9 @@ dpll_device_get_one(struct dpll_device *dpll, struct sk_buff *msg,
if (ret)
return ret;
ret = dpll_msg_add_phase_offset_avg_factor(msg, dpll, extack);
+ if (ret)
+ return ret;
+ ret = dpll_msg_add_freq_monitor(msg, dpll, extack);
if (ret)
return ret;
@@ -948,6 +1006,32 @@ dpll_phase_offset_avg_factor_set(struct dpll_device *dpll, struct nlattr *a,
extack);
}
+static int
+dpll_freq_monitor_set(struct dpll_device *dpll, struct nlattr *a,
+ struct netlink_ext_ack *extack)
+{
+ const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+ enum dpll_feature_state state = nla_get_u32(a), old_state;
+ int ret;
+
+ if (!(ops->freq_monitor_set && ops->freq_monitor_get)) {
+ NL_SET_ERR_MSG_ATTR(extack, a,
+ "dpll device not capable of frequency monitor");
+ return -EOPNOTSUPP;
+ }
+ ret = ops->freq_monitor_get(dpll, dpll_priv(dpll), &old_state,
+ extack);
+ if (ret) {
+ NL_SET_ERR_MSG(extack,
+ "unable to get current state of frequency monitor");
+ return ret;
+ }
+ if (state == old_state)
+ return 0;
+
+ return ops->freq_monitor_set(dpll, dpll_priv(dpll), state, extack);
+}
+
static int
dpll_pin_freq_set(struct dpll_pin *pin, struct nlattr *a,
struct netlink_ext_ack *extack)
@@ -1878,6 +1962,12 @@ dpll_set_from_nlattr(struct dpll_device *dpll, struct genl_info *info)
if (ret)
return ret;
break;
+ case DPLL_A_FREQUENCY_MONITOR:
+ ret = dpll_freq_monitor_set(dpll, a,
+ info->extack);
+ if (ret)
+ return ret;
+ break;
}
}
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index 2ce295b46b8cd..d14cdc2a37f62 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -52,6 +52,14 @@ struct dpll_device_ops {
int (*phase_offset_avg_factor_get)(const struct dpll_device *dpll,
void *dpll_priv, u32 *factor,
struct netlink_ext_ack *extack);
+ int (*freq_monitor_set)(const struct dpll_device *dpll,
+ void *dpll_priv,
+ enum dpll_feature_state state,
+ struct netlink_ext_ack *extack);
+ int (*freq_monitor_get)(const struct dpll_device *dpll,
+ void *dpll_priv,
+ enum dpll_feature_state *state,
+ struct netlink_ext_ack *extack);
};
struct dpll_pin_ops {
@@ -110,6 +118,10 @@ struct dpll_pin_ops {
int (*ffo_get)(const struct dpll_pin *pin, void *pin_priv,
const struct dpll_device *dpll, void *dpll_priv,
s64 *ffo, struct netlink_ext_ack *extack);
+ int (*actual_freq_get)(const struct dpll_pin *pin, void *pin_priv,
+ const struct dpll_device *dpll, void *dpll_priv,
+ u64 *actual_freq,
+ struct netlink_ext_ack *extack);
int (*esync_set)(const struct dpll_pin *pin, void *pin_priv,
const struct dpll_device *dpll, void *dpll_priv,
u64 freq, struct netlink_ext_ack *extack);
--
2.52.0On 25/03/2026 19:39, Ivan Vecera wrote:
> +static int dpll_msg_add_actual_freq(struct sk_buff *msg, struct dpll_pin *pin,
> + struct dpll_pin_ref *ref,
> + struct netlink_ext_ack *extack)
> +{
> + const struct dpll_device_ops *dev_ops = dpll_device_ops(ref->dpll);
> + const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
> + struct dpll_device *dpll = ref->dpll;
> + enum dpll_feature_state state;
> + u64 actual_freq;
> + int ret;
> +
> + if (!ops->actual_freq_get)
> + return 0;
> + if (dev_ops->freq_monitor_get) {
> + ret = dev_ops->freq_monitor_get(dpll, dpll_priv(dpll),
> + &state, extack);
> + if (ret)
> + return ret;
> + if (state == DPLL_FEATURE_STATE_DISABLE)
> + return 0;
I think we have to signal back to user that frequency monitoring is
disabled via extack.
> + }
> + ret = ops->actual_freq_get(pin, dpll_pin_on_dpll_priv(dpll, pin),
> + dpll, dpll_priv(dpll), &actual_freq, extack);
> + if (ret)
> + return ret;
> + if (nla_put_64bit(msg, DPLL_A_PIN_ACTUAL_FREQUENCY,
> + sizeof(actual_freq), &actual_freq, DPLL_A_PIN_PAD))
> + return -EMSGSIZE;
> +
> + return 0;
On 3/26/26 12:21 PM, Vadim Fedorenko wrote:
> On 25/03/2026 19:39, Ivan Vecera wrote:
>
>> +static int dpll_msg_add_actual_freq(struct sk_buff *msg, struct
>> dpll_pin *pin,
>> + struct dpll_pin_ref *ref,
>> + struct netlink_ext_ack *extack)
>> +{
>> + const struct dpll_device_ops *dev_ops = dpll_device_ops(ref->dpll);
>> + const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
>> + struct dpll_device *dpll = ref->dpll;
>> + enum dpll_feature_state state;
>> + u64 actual_freq;
>> + int ret;
>> +
>> + if (!ops->actual_freq_get)
>> + return 0;
>> + if (dev_ops->freq_monitor_get) {
>> + ret = dev_ops->freq_monitor_get(dpll, dpll_priv(dpll),
>> + &state, extack);
>> + if (ret)
>> + return ret;
>> + if (state == DPLL_FEATURE_STATE_DISABLE)
>> + return 0;
>
> I think we have to signal back to user that frequency monitoring is
> disabled via extack.
Hi Vadim,
This would break pin-get operation... Do or dump pin-get operation would
fail with this extack message.
Here we can check if the freq-monitoring is enabled and conditionally
call actual_freq_get() or measured_freq_get()
-or-
Call this callback unconditionally and check for return code and if a
driver returns e.g. -ENODATA then skip nla_put_64bit() but return
success.
WDYT?
Thanks,
Ivan
On 3/26/26 6:48 PM, Ivan Vecera wrote:
> On 3/26/26 12:21 PM, Vadim Fedorenko wrote:
>> On 25/03/2026 19:39, Ivan Vecera wrote:
>>
>>> +static int dpll_msg_add_actual_freq(struct sk_buff *msg, struct
>>> dpll_pin *pin,
>>> + struct dpll_pin_ref *ref,
>>> + struct netlink_ext_ack *extack)
>>> +{
>>> + const struct dpll_device_ops *dev_ops = dpll_device_ops(ref->dpll);
>>> + const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
>>> + struct dpll_device *dpll = ref->dpll;
>>> + enum dpll_feature_state state;
>>> + u64 actual_freq;
>>> + int ret;
>>> +
>>> + if (!ops->actual_freq_get)
>>> + return 0;
>>> + if (dev_ops->freq_monitor_get) {
>>> + ret = dev_ops->freq_monitor_get(dpll, dpll_priv(dpll),
>>> + &state, extack);
>>> + if (ret)
>>> + return ret;
>>> + if (state == DPLL_FEATURE_STATE_DISABLE)
>>> + return 0;
>>
>> I think we have to signal back to user that frequency monitoring is
>> disabled via extack.
>
> Hi Vadim,
>
> This would break pin-get operation... Do or dump pin-get operation would
> fail with this extack message.
>
> Here we can check if the freq-monitoring is enabled and conditionally
> call actual_freq_get() or measured_freq_get()
>
> -or-
>
> Call this callback unconditionally and check for return code and if a
> driver returns e.g. -ENODATA then skip nla_put_64bit() but return
> success.
>
> WDYT?
Vadim?
On 30/03/2026 09:52, Ivan Vecera wrote:
> On 3/26/26 6:48 PM, Ivan Vecera wrote:
>> On 3/26/26 12:21 PM, Vadim Fedorenko wrote:
>>> On 25/03/2026 19:39, Ivan Vecera wrote:
>>>
>>>> +static int dpll_msg_add_actual_freq(struct sk_buff *msg, struct
>>>> dpll_pin *pin,
>>>> + struct dpll_pin_ref *ref,
>>>> + struct netlink_ext_ack *extack)
>>>> +{
>>>> + const struct dpll_device_ops *dev_ops = dpll_device_ops(ref-
>>>> >dpll);
>>>> + const struct dpll_pin_ops *ops = dpll_pin_ops(ref);
>>>> + struct dpll_device *dpll = ref->dpll;
>>>> + enum dpll_feature_state state;
>>>> + u64 actual_freq;
>>>> + int ret;
>>>> +
>>>> + if (!ops->actual_freq_get)
>>>> + return 0;
>>>> + if (dev_ops->freq_monitor_get) {
>>>> + ret = dev_ops->freq_monitor_get(dpll, dpll_priv(dpll),
>>>> + &state, extack);
>>>> + if (ret)
>>>> + return ret;
>>>> + if (state == DPLL_FEATURE_STATE_DISABLE)
>>>> + return 0;
>>>
>>> I think we have to signal back to user that frequency monitoring is
>>> disabled via extack.
>>
>> Hi Vadim,
>>
>> This would break pin-get operation... Do or dump pin-get operation would
>> fail with this extack message.
>>
>> Here we can check if the freq-monitoring is enabled and conditionally
>> call actual_freq_get() or measured_freq_get()
Let's make it this way, we don't want to waste even small amount of
resources for useless call.
>>
>> -or-
>>
>> Call this callback unconditionally and check for return code and if a
>> driver returns e.g. -ENODATA then skip nla_put_64bit() but return
>> success.
>>
>> WDYT?
>
> Vadim?
Sorry, was AFK this Friday/weekend
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