Message-ID: <6416658d.df0a0220.cb6f6.f5d2@mx.google.com>
Date:   Sat, 18 Mar 2023 20:14:21 +0100
From:   Christian Marangi <ansuelsmth@gmail.com>
To:     Michal Kubiak <michal.kubiak@intel.com>
Cc:     Andrew Lunn <andrew@lunn.ch>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Vladimir Oltean <olteanv@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>,
        Gregory Clement <gregory.clement@bootlin.com>,
        Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        John Crispin <john@phrozen.org>, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-arm-msm@vger.kernel.org, Lee Jones <lee@kernel.org>,
        linux-leds@vger.kernel.org
Subject: Re: [net-next PATCH v4 03/14] net: dsa: qca8k: add LEDs blink_set()
 support
References: <20230317023125.486-1-ansuelsmth@gmail.com>
 <20230317023125.486-4-ansuelsmth@gmail.com>
 <ZBRU4Xx3kCwbD3Eg@localhost.localdomain>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <ZBRU4Xx3kCwbD3Eg@localhost.localdomain>
Precedence: bulk

On Fri, Mar 17, 2023 at 12:54:09PM +0100, Michal Kubiak wrote:
> 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?
>

Since they are really the same thing, I added a big comment that explain
how the thing mask shift and reg works and why in the brightness_set
function.

> > +
> > +	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

-- 
	Ansuel