diff mbox series

[v7,1/2] pwm: meson: Add support for Amlogic S4 PWM

Message ID 20240605-s4-pwm-v7-1-e822b271d7b0@amlogic.com (mailing list archive)
State New, archived
Headers show
Series Add support for Amlogic S4 PWM | expand

Commit Message

Kelvin Zhang via B4 Relay June 5, 2024, 2:44 a.m. UTC 
From: Junyi Zhao <junyi.zhao@amlogic.com>

Add support for Amlogic S4 PWM.

Signed-off-by: Junyi Zhao <junyi.zhao@amlogic.com>
Signed-off-by: Kelvin Zhang <kelvin.zhang@amlogic.com>
---
 drivers/pwm/pwm-meson.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

Comments

George Stark June 5, 2024, 12:12 p.m. UTC | #1 
Hello Kelvin, Junyi

On 6/5/24 05:44, Kelvin Zhang via B4 Relay wrote:
> From: Junyi Zhao <junyi.zhao@amlogic.com>
> 
> Add support for Amlogic S4 PWM.
> 
> Signed-off-by: Junyi Zhao <junyi.zhao@amlogic.com>
> Signed-off-by: Kelvin Zhang <kelvin.zhang@amlogic.com>
> ---
>   drivers/pwm/pwm-meson.c | 36 ++++++++++++++++++++++++++++++++++++
>   1 file changed, 36 insertions(+)
> 
> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
> index b2f97dfb01bb..4f01847525b2 100644
> --- a/drivers/pwm/pwm-meson.c
> +++ b/drivers/pwm/pwm-meson.c
> @@ -460,6 +460,34 @@ static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip)
>   	return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
>   }
>   
> +static void meson_pwm_s4_put_clk(void *data)
> +{
> +	struct clk *clk = data;
> +
> +	clk_put(clk);
> +}
> +
> +static int meson_pwm_init_channels_s4(struct pwm_chip *chip)
> +{
> +	struct device *dev = pwmchip_parent(chip);
> +	struct device_node *np = dev->of_node;
> +	struct meson_pwm *meson = to_meson_pwm(chip);
> +	int i, ret;
> +
> +	for (i = 0; i < MESON_NUM_PWMS; i++) {
> +		meson->channels[i].clk = of_clk_get(np, i);
> +		if (IS_ERR(meson->channels[i].clk)) {
> +			ret = PTR_ERR(meson->channels[i].clk);
> +			dev_err_probe(dev, ret, "Failed to get clk\n");
> +			return ret;
> +		}
> +		devm_add_action_or_reset(dev, meson_pwm_s4_put_clk,
> +					 meson->channels[i].clk);

devm_add_action_or_reset() result should be checked

> +	}
> +
> +	return 0;
> +}

You can rewrite it a bit to always have a single allocation for devm node:

static void meson_pwm_s4_put_clk(void *data)
{
	struct meson_pwm *meson = data;
	int i;

	for (i = 0; i < MESON_NUM_PWMS; i++)
		clk_put(meson->channels[i].clk);
}

static int meson_pwm_init_channels_s4(struct pwm_chip *chip)
{
	struct device *dev = pwmchip_parent(chip);
	struct device_node *np = dev->of_node;
	struct meson_pwm *meson = to_meson_pwm(chip);
	int i, ret;

	ret = devm_add_action(dev, meson_pwm_s4_put_clk, meson);
	if (ret)
		return ret;

	for (i = 0; i < MESON_NUM_PWMS; i++) {
		meson->channels[i].clk = of_clk_get(np, i);
		if (IS_ERR(meson->channels[i].clk)) {
			ret = PTR_ERR(meson->channels[i].clk);
			dev_err_probe(dev, ret, "Failed to get clk\n");
			return ret;
		}
	}

	return 0;
}
Jerome Brunet June 12, 2024, 8:15 a.m. UTC | #2 
On Wed 05 Jun 2024 at 15:12, George Stark <gnstark@salutedevices.com> wrote:

> Hello Kelvin, Junyi
>
> On 6/5/24 05:44, Kelvin Zhang via B4 Relay wrote:
>> From: Junyi Zhao <junyi.zhao@amlogic.com>
>> Add support for Amlogic S4 PWM.
>> Signed-off-by: Junyi Zhao <junyi.zhao@amlogic.com>
>> Signed-off-by: Kelvin Zhang <kelvin.zhang@amlogic.com>
>> ---
>>   drivers/pwm/pwm-meson.c | 36 ++++++++++++++++++++++++++++++++++++
>>   1 file changed, 36 insertions(+)
>> diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
>> index b2f97dfb01bb..4f01847525b2 100644
>> --- a/drivers/pwm/pwm-meson.c
>> +++ b/drivers/pwm/pwm-meson.c
>> @@ -460,6 +460,34 @@ static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip)
>>   	return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
>>   }
>>   +static void meson_pwm_s4_put_clk(void *data)
>> +{
>> +	struct clk *clk = data;
>> +
>> +	clk_put(clk);
>> +}
>> +
>> +static int meson_pwm_init_channels_s4(struct pwm_chip *chip)
>> +{
>> +	struct device *dev = pwmchip_parent(chip);
>> +	struct device_node *np = dev->of_node;
>> +	struct meson_pwm *meson = to_meson_pwm(chip);
>> +	int i, ret;
>> +
>> +	for (i = 0; i < MESON_NUM_PWMS; i++) {
>> +		meson->channels[i].clk = of_clk_get(np, i);
>> +		if (IS_ERR(meson->channels[i].clk)) {
>> +			ret = PTR_ERR(meson->channels[i].clk);
>> +			dev_err_probe(dev, ret, "Failed to get clk\n");
>> +			return ret;
>> +		}
>> +		devm_add_action_or_reset(dev, meson_pwm_s4_put_clk,
>> +					 meson->channels[i].clk);
>
> devm_add_action_or_reset() result should be checked
>
>> +	}
>> +
>> +	return 0;
>> +}
>
> You can rewrite it a bit to always have a single allocation for devm node:
>
> static void meson_pwm_s4_put_clk(void *data)
> {
> 	struct meson_pwm *meson = data;
> 	int i;
>
> 	for (i = 0; i < MESON_NUM_PWMS; i++)
> 		clk_put(meson->channels[i].clk);
> }

This has already been discussed on v6.

This make the code un-necessarily complex and potentially put clock that
have not even been claimed.

>
> static int meson_pwm_init_channels_s4(struct pwm_chip *chip)
> {
> 	struct device *dev = pwmchip_parent(chip);
> 	struct device_node *np = dev->of_node;
> 	struct meson_pwm *meson = to_meson_pwm(chip);
> 	int i, ret;
>
> 	ret = devm_add_action(dev, meson_pwm_s4_put_clk, meson);
> 	if (ret)
> 		return ret;
>
> 	for (i = 0; i < MESON_NUM_PWMS; i++) {
> 		meson->channels[i].clk = of_clk_get(np, i);
> 		if (IS_ERR(meson->channels[i].clk)) {
> 			ret = PTR_ERR(meson->channels[i].clk);
> 			dev_err_probe(dev, ret, "Failed to get clk\n");
> 			return ret;
> 		}
> 	}
>
> 	return 0;
> }
diff mbox series

Patch

diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index b2f97dfb01bb..4f01847525b2 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -460,6 +460,34 @@  static int meson_pwm_init_channels_meson8b_v2(struct pwm_chip *chip)
 	return meson_pwm_init_clocks_meson8b(chip, mux_parent_data);
 }
 
+static void meson_pwm_s4_put_clk(void *data)
+{
+	struct clk *clk = data;
+
+	clk_put(clk);
+}
+
+static int meson_pwm_init_channels_s4(struct pwm_chip *chip)
+{
+	struct device *dev = pwmchip_parent(chip);
+	struct device_node *np = dev->of_node;
+	struct meson_pwm *meson = to_meson_pwm(chip);
+	int i, ret;
+
+	for (i = 0; i < MESON_NUM_PWMS; i++) {
+		meson->channels[i].clk = of_clk_get(np, i);
+		if (IS_ERR(meson->channels[i].clk)) {
+			ret = PTR_ERR(meson->channels[i].clk);
+			dev_err_probe(dev, ret, "Failed to get clk\n");
+			return ret;
+		}
+		devm_add_action_or_reset(dev, meson_pwm_s4_put_clk,
+					 meson->channels[i].clk);
+	}
+
+	return 0;
+}
+
 static const struct meson_pwm_data pwm_meson8b_data = {
 	.parent_names = { "xtal", NULL, "fclk_div4", "fclk_div3" },
 	.channels_init = meson_pwm_init_channels_meson8b_legacy,
@@ -498,6 +526,10 @@  static const struct meson_pwm_data pwm_meson8_v2_data = {
 	.channels_init = meson_pwm_init_channels_meson8b_v2,
 };
 
+static const struct meson_pwm_data pwm_s4_data = {
+	.channels_init = meson_pwm_init_channels_s4,
+};
+
 static const struct of_device_id meson_pwm_matches[] = {
 	{
 		.compatible = "amlogic,meson8-pwm-v2",
@@ -536,6 +568,10 @@  static const struct of_device_id meson_pwm_matches[] = {
 		.compatible = "amlogic,meson-g12a-ao-pwm-cd",
 		.data = &pwm_g12a_ao_cd_data
 	},
+	{
+		.compatible = "amlogic,meson-s4-pwm",
+		.data = &pwm_s4_data
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, meson_pwm_matches);