Re: [net-next PATCH v4 03/14] net: dsa: qca8k: add LEDs blink_set() support

[Michal Kubiak <michal.kubiak@intel.com>]

On Fri, Mar 17, 2023 at 03:31:14AM +0100, Christian Marangi wrote:
> Add LEDs blink_set() support to qca8k Switch Family.
> These LEDs support hw accellerated blinking at a fixed rate
> of 4Hz.
> 
> Reject any other value since not supported by the LEDs switch.
> 
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> ---
>  drivers/net/dsa/qca/qca8k-leds.c | 38 ++++++++++++++++++++++++++++++++
>  1 file changed, 38 insertions(+)
> 
> diff --git a/drivers/net/dsa/qca/qca8k-leds.c b/drivers/net/dsa/qca/qca8k-leds.c
> index adbe7f6e2994..c229575c7e8c 100644
> --- a/drivers/net/dsa/qca/qca8k-leds.c
> +++ b/drivers/net/dsa/qca/qca8k-leds.c
> @@ -92,6 +92,43 @@ qca8k_led_brightness_get(struct qca8k_led *led)
>  	return val == QCA8K_LED_ALWAYS_ON;
>  }
>  
> +static int
> +qca8k_cled_blink_set(struct led_classdev *ldev,
> +		     unsigned long *delay_on,
> +		     unsigned long *delay_off)
> +{
> +	struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev);
> +	u32 mask, val = QCA8K_LED_ALWAYS_BLINK_4HZ;
> +	struct qca8k_led_pattern_en reg_info;
> +	struct qca8k_priv *priv = led->priv;
> +
> +	if (*delay_on == 0 && *delay_off == 0) {
> +		*delay_on = 125;
> +		*delay_off = 125;
> +	}
> +
> +	if (*delay_on != 125 || *delay_off != 125) {
> +		/* The hardware only supports blinking at 4Hz. Fall back
> +		 * to software implementation in other cases.
> +		 */
> +		return -EINVAL;
> +	}
> +
> +	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
> +
> +	if (led->port_num == 0 || led->port_num == 4) {
> +		mask = QCA8K_LED_PATTERN_EN_MASK;
> +		val <<= QCA8K_LED_PATTERN_EN_SHIFT;
> +	} else {
> +		mask = QCA8K_LED_PHY123_PATTERN_EN_MASK;
> +	}

Could you add a comment as to why the HW requires different approaches for
inner and outer ports?

> +
> +	regmap_update_bits(priv->regmap, reg_info.reg, mask << reg_info.shift,
> +			   val << reg_info.shift);
> +
> +	return 0;
> +}
> +
>  static int
>  qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int port_num)
>  {
> @@ -149,6 +186,7 @@ qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int p
>  
>  		port_led->cdev.max_brightness = 1;
>  		port_led->cdev.brightness_set_blocking = qca8k_cled_brightness_set_blocking;
> +		port_led->cdev.blink_set = qca8k_cled_blink_set;
>  		init_data.default_label = ":port";
>  		init_data.devicename = "qca8k";
>  		init_data.fwnode = led;
> -- 
> 2.39.2
> 


Thanks,
Michal