diff mbox series

[V3,RESEND] pwm: meson: add pwm support for S4

Message ID 20231016052457.1191838-1-junyi.zhao@amlogic.com (mailing list archive)
State New, archived
Headers show
Series [V3,RESEND] pwm: meson: add pwm support for S4 | expand

Commit Message

Junyi Zhao Oct. 16, 2023, 5:24 a.m. UTC
From: "junyi.zhao" <junyi.zhao@amlogic.com>

Support PWM for S4 soc.
Now the PWM clock input is done in independent CLKCTRL registers.
And no more in the PWM registers.
PWM needs to obtain an external clock source.

Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
---
V2 -> V3: 
Rebase and Review the latest upstream code again.
After reconstruction, stick to the previous code as much as possible.
 drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)


base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36

Comments

Yixun Lan Oct. 16, 2023, 10:37 p.m. UTC | #1
Hi JunYi

On 13:24 Mon 16 Oct     , JunYi Zhao wrote:
> From: "junyi.zhao" <junyi.zhao@amlogic.com>
> 
> Support PWM for S4 soc.
> Now the PWM clock input is done in independent CLKCTRL registers.
> And no more in the PWM registers.
> PWM needs to obtain an external clock source.
> 
> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
> ---
> V2 -> V3: 
> Rebase and Review the latest upstream code again.
> After reconstruction, stick to the previous code as much as possible.
>  drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
> index 25519cddc2a9..fe9fd75747c4 100644
> --- a/drivers/pwm/pwm-meson.c
> +++ b/drivers/pwm/pwm-meson.c
> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>  struct meson_pwm_data {
>  	const char * const *parent_names;
>  	unsigned int num_parents;
> +	unsigned int extern_clk;
>  };
>  
>  struct meson_pwm {
> @@ -396,6 +397,10 @@ static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
>  	.num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>  };
>  
> +static const struct meson_pwm_data pwm_s4_data = {
> +	.extern_clk = true,
> +};
> +
>  static const struct of_device_id meson_pwm_matches[] = {
>  	{
>  		.compatible = "amlogic,meson8b-pwm",
> @@ -429,6 +434,10 @@ static const struct of_device_id meson_pwm_matches[] = {
>  		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
>  		.data = &pwm_g12a_ao_cd_data
>  	},
> +	{
> +		.compatible = "amlogic,s4-pwm",
> +		.data = &pwm_s4_data,
> +	},
>  	{},
>  };
>  MODULE_DEVICE_TABLE(of, meson_pwm_matches);
> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
>  		struct clk_parent_data div_parent = {}, gate_parent = {};
>  		struct clk_init_data init = {};
>  
> +		if (meson->data->extern_clk) {
> +			snprintf(name, sizeof(name), "clkin%u", i);
> +			channel->clk = devm_clk_get(dev, name);
use devm_clk_get_optional() which would save you from introducing
the 'extern_clk' variable

> +			if (IS_ERR(channel->clk)) {
> +				dev_err(meson->chip.dev, "can't get device clock\n");
> +				return PTR_ERR(channel->clk);
> +			}
> +			continue;
> +		}
> +
>  		snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>  
>  		init.name = name;
> 
> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
> -- 
> 2.41.0
> 
> 
> _______________________________________________
> linux-amlogic mailing list
> linux-amlogic@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-amlogic
George Stark Oct. 23, 2023, 7:40 p.m. UTC | #2
Hello Yixun Lan

On 10/17/23 01:37, Yixun Lan wrote:
> Hi JunYi
> 
> On 13:24 Mon 16 Oct     , JunYi Zhao wrote:
>> From: "junyi.zhao" <junyi.zhao@amlogic.com>
>>
>> Support PWM for S4 soc.
>> Now the PWM clock input is done in independent CLKCTRL registers.
>> And no more in the PWM registers.
>> PWM needs to obtain an external clock source.
>>
>> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
>> ---
>> V2 -> V3:
>> Rebase and Review the latest upstream code again.
>> After reconstruction, stick to the previous code as much as possible.
>>   drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>>   1 file changed, 19 insertions(+)
>>
>> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
>> index 25519cddc2a9..fe9fd75747c4 100644
>> --- a/drivers/pwm/pwm-meson.c
>> +++ b/drivers/pwm/pwm-meson.c
>> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>>   struct meson_pwm_data {
>>   	const char * const *parent_names;
>>   	unsigned int num_parents;
>> +	unsigned int extern_clk;
>>   };
>>   
>>   struct meson_pwm {
>> @@ -396,6 +397,10 @@ static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
>>   	.num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>>   };
>>   
>> +static const struct meson_pwm_data pwm_s4_data = {
>> +	.extern_clk = true,
>> +};
>> +
>>   static const struct of_device_id meson_pwm_matches[] = {
>>   	{
>>   		.compatible = "amlogic,meson8b-pwm",
>> @@ -429,6 +434,10 @@ static const struct of_device_id meson_pwm_matches[] = {
>>   		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
>>   		.data = &pwm_g12a_ao_cd_data
>>   	},
>> +	{
>> +		.compatible = "amlogic,s4-pwm",
>> +		.data = &pwm_s4_data,
>> +	},
>>   	{},
>>   };
>>   MODULE_DEVICE_TABLE(of, meson_pwm_matches);
>> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
>>   		struct clk_parent_data div_parent = {}, gate_parent = {};
>>   		struct clk_init_data init = {};
>>   
>> +		if (meson->data->extern_clk) {
>> +			snprintf(name, sizeof(name), "clkin%u", i);
>> +			channel->clk = devm_clk_get(dev, name);
> use devm_clk_get_optional() which would save you from introducing
> the 'extern_clk' variable

On S4 and other recent chips PWM clock resides in separate IP and it 
must be provided to driver in order to control PWM frequency. So this 
clock is not optional.

> 
>> +			if (IS_ERR(channel->clk)) {
>> +				dev_err(meson->chip.dev, "can't get device clock\n");
>> +				return PTR_ERR(channel->clk);
>> +			}
>> +			continue;
>> +		}
>> +
>>   		snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>>   
>>   		init.name = name;
>>
>> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
>> -- 
>> 2.41.0
>>
>>
>> _______________________________________________
>> linux-amlogic mailing list
>> linux-amlogic@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-amlogic
>
George Stark Oct. 23, 2023, 8:07 p.m. UTC | #3
Hello JunYi Zhao

On 10/16/23 08:24, JunYi Zhao wrote:
> From: "junyi.zhao" <junyi.zhao@amlogic.com>
> 
> Support PWM for S4 soc.
> Now the PWM clock input is done in independent CLKCTRL registers.
> And no more in the PWM registers.
> PWM needs to obtain an external clock source.
> 
> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
> ---
> V2 -> V3:
> Rebase and Review the latest upstream code again.
> After reconstruction, stick to the previous code as much as possible.
>   drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>   1 file changed, 19 insertions(+)
> 
> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
> index 25519cddc2a9..fe9fd75747c4 100644
> --- a/drivers/pwm/pwm-meson.c
> +++ b/drivers/pwm/pwm-meson.c
> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>   struct meson_pwm_data {
>   	const char * const *parent_names;
>   	unsigned int num_parents;
> +	unsigned int extern_clk;
may be bool extern_clk;
>   };
>   
>   struct meson_pwm {
> @@ -396,6 +397,10 @@ static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
>   	.num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>   };
>   
> +static const struct meson_pwm_data pwm_s4_data = {
> +	.extern_clk = true,
> +};
> +
>   static const struct of_device_id meson_pwm_matches[] = {
>   	{
>   		.compatible = "amlogic,meson8b-pwm",
> @@ -429,6 +434,10 @@ static const struct of_device_id meson_pwm_matches[] = {
>   		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
>   		.data = &pwm_g12a_ao_cd_data
>   	},
> +	{
> +		.compatible = "amlogic,s4-pwm",
> +		.data = &pwm_s4_data,
> +	},
>   	{},
>   };
>   MODULE_DEVICE_TABLE(of, meson_pwm_matches);
> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
>   		struct clk_parent_data div_parent = {}, gate_parent = {};
>   		struct clk_init_data init = {};
>   
> +		if (meson->data->extern_clk) {
> +			snprintf(name, sizeof(name), "clkin%u", i);
> +			channel->clk = devm_clk_get(dev, name);
> +			if (IS_ERR(channel->clk)) {
> +				dev_err(meson->chip.dev, "can't get device clock\n");
> +				return PTR_ERR(channel->clk);
> +			}
> +			continue;
> +		}
> +
>   		snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>   
>   		init.name = name;
> 
> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
Junyi Zhao Oct. 27, 2023, 9:22 a.m. UTC | #4
Hello YiXun,
  CLK config has been separated on HW. No more in pwmchip.
And s4 datasheet about clk updated already.

On 2023/10/24 3:40, George Stark wrote:
> [你通常不会收到来自 gnstark@salutedevices.com 的电子邮件。请访问 
> https://aka.ms/LearnAboutSenderIdentification,以了解这一点为什么很重要]
> 
> [ EXTERNAL EMAIL ]
> 
> Hello Yixun Lan
> 
> On 10/17/23 01:37, Yixun Lan wrote:
>> Hi JunYi
>>
>> On 13:24 Mon 16 Oct     , JunYi Zhao wrote:
>>> From: "junyi.zhao" <junyi.zhao@amlogic.com>
>>>
>>> Support PWM for S4 soc.
>>> Now the PWM clock input is done in independent CLKCTRL registers.
>>> And no more in the PWM registers.
>>> PWM needs to obtain an external clock source.
>>>
>>> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
>>> ---
>>> V2 -> V3:
>>> Rebase and Review the latest upstream code again.
>>> After reconstruction, stick to the previous code as much as possible.
>>>   drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>>>   1 file changed, 19 insertions(+)
>>>
>>> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
>>> index 25519cddc2a9..fe9fd75747c4 100644
>>> --- a/drivers/pwm/pwm-meson.c
>>> +++ b/drivers/pwm/pwm-meson.c
>>> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>>>   struct meson_pwm_data {
>>>      const char * const *parent_names;
>>>      unsigned int num_parents;
>>> +    unsigned int extern_clk;
>>>   };
>>>
>>>   struct meson_pwm {
>>> @@ -396,6 +397,10 @@ static const struct meson_pwm_data 
>>> pwm_g12a_ao_cd_data = {
>>>      .num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>>>   };
>>>
>>> +static const struct meson_pwm_data pwm_s4_data = {
>>> +    .extern_clk = true,
>>> +};
>>> +
>>>   static const struct of_device_id meson_pwm_matches[] = {
>>>      {
>>>              .compatible = "amlogic,meson8b-pwm",
>>> @@ -429,6 +434,10 @@ static const struct of_device_id 
>>> meson_pwm_matches[] = {
>>>              .compatible = "amlogic,meson-g12a-ao-pwm-cd",
>>>              .data = &pwm_g12a_ao_cd_data
>>>      },
>>> +    {
>>> +            .compatible = "amlogic,s4-pwm",
>>> +            .data = &pwm_s4_data,
>>> +    },
>>>      {},
>>>   };
>>>   MODULE_DEVICE_TABLE(of, meson_pwm_matches);
>>> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct 
>>> meson_pwm *meson)
>>>              struct clk_parent_data div_parent = {}, gate_parent = {};
>>>              struct clk_init_data init = {};
>>>
>>> +            if (meson->data->extern_clk) {
>>> +                    snprintf(name, sizeof(name), "clkin%u", i);
>>> +                    channel->clk = devm_clk_get(dev, name);
>> use devm_clk_get_optional() which would save you from introducing
>> the 'extern_clk' variable
> 
> On S4 and other recent chips PWM clock resides in separate IP and it
> must be provided to driver in order to control PWM frequency. So this
> clock is not optional.
> 
>>
>>> +                    if (IS_ERR(channel->clk)) {
>>> +                            dev_err(meson->chip.dev, "can't get 
>>> device clock\n");
>>> +                            return PTR_ERR(channel->clk);
>>> +                    }
>>> +                    continue;
>>> +            }
>>> +
>>>              snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>>>
>>>              init.name = name;
>>>
>>> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
>>> -- 
>>> 2.41.0
>>>
>>>
>>> _______________________________________________
>>> linux-amlogic mailing list
>>> linux-amlogic@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-amlogic
>>
> 
> -- 
> Best regards
> George
Junyi Zhao Oct. 27, 2023, 9:34 a.m. UTC | #5
Hi George, thank u for your review.
I will change it.

On 2023/10/24 4:07, George Stark wrote:
> [你通常不会收到来自 gnstark@salutedevices.com 的电子邮件。请访问 
> https://aka.ms/LearnAboutSenderIdentification,以了解这一点为什么很重要]
> 
> [ EXTERNAL EMAIL ]
> 
> Hello JunYi Zhao
> 
> On 10/16/23 08:24, JunYi Zhao wrote:
>> From: "junyi.zhao" <junyi.zhao@amlogic.com>
>>
>> Support PWM for S4 soc.
>> Now the PWM clock input is done in independent CLKCTRL registers.
>> And no more in the PWM registers.
>> PWM needs to obtain an external clock source.
>>
>> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
>> ---
>> V2 -> V3:
>> Rebase and Review the latest upstream code again.
>> After reconstruction, stick to the previous code as much as possible.
>>   drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>>   1 file changed, 19 insertions(+)
>>
>> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
>> index 25519cddc2a9..fe9fd75747c4 100644
>> --- a/drivers/pwm/pwm-meson.c
>> +++ b/drivers/pwm/pwm-meson.c
>> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>>   struct meson_pwm_data {
>>       const char * const *parent_names;
>>       unsigned int num_parents;
>> +     unsigned int extern_clk;
> may be bool extern_clk;
>>   };
>>
>>   struct meson_pwm {
>> @@ -396,6 +397,10 @@ static const struct meson_pwm_data 
>> pwm_g12a_ao_cd_data = {
>>       .num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>>   };
>>
>> +static const struct meson_pwm_data pwm_s4_data = {
>> +     .extern_clk = true,
>> +};
>> +
>>   static const struct of_device_id meson_pwm_matches[] = {
>>       {
>>               .compatible = "amlogic,meson8b-pwm",
>> @@ -429,6 +434,10 @@ static const struct of_device_id 
>> meson_pwm_matches[] = {
>>               .compatible = "amlogic,meson-g12a-ao-pwm-cd",
>>               .data = &pwm_g12a_ao_cd_data
>>       },
>> +     {
>> +             .compatible = "amlogic,s4-pwm",
>> +             .data = &pwm_s4_data,
>> +     },
>>       {},
>>   };
>>   MODULE_DEVICE_TABLE(of, meson_pwm_matches);
>> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct 
>> meson_pwm *meson)
>>               struct clk_parent_data div_parent = {}, gate_parent = {};
>>               struct clk_init_data init = {};
>>
>> +             if (meson->data->extern_clk) {
>> +                     snprintf(name, sizeof(name), "clkin%u", i);
>> +                     channel->clk = devm_clk_get(dev, name);
>> +                     if (IS_ERR(channel->clk)) {
>> +                             dev_err(meson->chip.dev, "can't get 
>> device clock\n");
>> +                             return PTR_ERR(channel->clk);
>> +                     }
>> +                     continue;
>> +             }
>> +
>>               snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>>
>>               init.name = name;
>>
>> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
> 
> -- 
> Best regards
> George
Jerome Brunet Oct. 27, 2023, 10 a.m. UTC | #6
On Mon 23 Oct 2023 at 23:07, George Stark <gnstark@salutedevices.com> wrote:

> Hello JunYi Zhao
>
> On 10/16/23 08:24, JunYi Zhao wrote:
>> From: "junyi.zhao" <junyi.zhao@amlogic.com>
>> Support PWM for S4 soc.
>> Now the PWM clock input is done in independent CLKCTRL registers.
>> And no more in the PWM registers.
>> PWM needs to obtain an external clock source.
>> Signed-off-by: junyi.zhao <junyi.zhao@amlogic.com>
>> ---
>> V2 -> V3:
>> Rebase and Review the latest upstream code again.
>> After reconstruction, stick to the previous code as much as possible.
>>   drivers/pwm/pwm-meson.c | 19 +++++++++++++++++++
>>   1 file changed, 19 insertions(+)
>> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
>> index 25519cddc2a9..fe9fd75747c4 100644
>> --- a/drivers/pwm/pwm-meson.c
>> +++ b/drivers/pwm/pwm-meson.c
>> @@ -99,6 +99,7 @@ struct meson_pwm_channel {
>>   struct meson_pwm_data {
>>   	const char * const *parent_names;
>>   	unsigned int num_parents;
>> +	unsigned int extern_clk;
> may be bool extern_clk;
>>   };
>>     struct meson_pwm {
>> @@ -396,6 +397,10 @@ static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
>>   	.num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
>>   };
>>   +static const struct meson_pwm_data pwm_s4_data = {
>> +	.extern_clk = true,
>> +};
>> +
>>   static const struct of_device_id meson_pwm_matches[] = {
>>   	{
>>   		.compatible = "amlogic,meson8b-pwm",
>> @@ -429,6 +434,10 @@ static const struct of_device_id meson_pwm_matches[] = {
>>   		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
>>   		.data = &pwm_g12a_ao_cd_data
>>   	},
>> +	{
>> +		.compatible = "amlogic,s4-pwm",
>> +		.data = &pwm_s4_data,
>> +	},
>>   	{},
>>   };
>>   MODULE_DEVICE_TABLE(of, meson_pwm_matches);
>> @@ -451,6 +460,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson)
>>   		struct clk_parent_data div_parent = {}, gate_parent = {};
>>   		struct clk_init_data init = {};
>>   +		if (meson->data->extern_clk) {

Instead of hacking through the existing registration function, it be
much better to provide the clock registration function as on ops in dt data.

Also, as Neil pointed out on the v2 [1], the meaning of clkin0/1 is changed
on this SoC.
* On previous SoC, it was a reference to clock input the PWM block
  should select from the hard-coded list it has (should fix that
  someday)
* Now it is directly the input the PWM block must claim.

You need to update the bindings accordingly for the S4

[1]: https://lore.kernel.org/linux-amlogic/07581fb8-0cd9-5b76-6fa3-1d1a7353d944@baylibre.com

>> +			snprintf(name, sizeof(name), "clkin%u", i);
>> +			channel->clk = devm_clk_get(dev, name);
>> +			if (IS_ERR(channel->clk)) {
>> +				dev_err(meson->chip.dev, "can't get device clock\n");
>> +				return PTR_ERR(channel->clk);
>> +			}
>> +			continue;
>> +		}
>> +
>>   		snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
>>     		init.name = name;
>> base-commit: 4d2c646ac07cf4a35ef1c4a935a1a4fd6c6b1a36
diff mbox series

Patch

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index 25519cddc2a9..fe9fd75747c4 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -99,6 +99,7 @@  struct meson_pwm_channel {
 struct meson_pwm_data {
 	const char * const *parent_names;
 	unsigned int num_parents;
+	unsigned int extern_clk;
 };
 
 struct meson_pwm {
@@ -396,6 +397,10 @@  static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
 	.num_parents = ARRAY_SIZE(pwm_g12a_ao_cd_parent_names),
 };
 
+static const struct meson_pwm_data pwm_s4_data = {
+	.extern_clk = true,
+};
+
 static const struct of_device_id meson_pwm_matches[] = {
 	{
 		.compatible = "amlogic,meson8b-pwm",
@@ -429,6 +434,10 @@  static const struct of_device_id meson_pwm_matches[] = {
 		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
 		.data = &pwm_g12a_ao_cd_data
 	},
+	{
+		.compatible = "amlogic,s4-pwm",
+		.data = &pwm_s4_data,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, meson_pwm_matches);
@@ -451,6 +460,16 @@  static int meson_pwm_init_channels(struct meson_pwm *meson)
 		struct clk_parent_data div_parent = {}, gate_parent = {};
 		struct clk_init_data init = {};
 
+		if (meson->data->extern_clk) {
+			snprintf(name, sizeof(name), "clkin%u", i);
+			channel->clk = devm_clk_get(dev, name);
+			if (IS_ERR(channel->clk)) {
+				dev_err(meson->chip.dev, "can't get device clock\n");
+				return PTR_ERR(channel->clk);
+			}
+			continue;
+		}
+
 		snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
 
 		init.name = name;