diff mbox series

[net-next,v2,02/14] net: dsa: qca8k: add LEDs basic support

Message ID 20230309223524.23364-3-ansuelsmth@gmail.com
State Superseded
Headers show
Series net: Add basic LED support for switch/phy | expand

Commit Message

Christian Marangi March 9, 2023, 10:35 p.m. UTC
Add LEDs basic support for qca8k Switch Family by adding basic
brightness_set() and brightness_get() support.

Since these LEDs refelect port status, the default label is set to
":port". DT binding should describe the color, function and number of
the leds using standard LEDs api.

These LEDs supports only blocking variant of the brightness_set()
function since they can sleep during access of the switch leds to set
the brightness.

While at it add to the qca8k header file each mode defined by the Switch
Documentation for future use.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/net/dsa/qca/Kconfig      |   7 ++
 drivers/net/dsa/qca/Makefile     |   1 +
 drivers/net/dsa/qca/qca8k-8xxx.c |   4 +
 drivers/net/dsa/qca/qca8k-leds.c | 198 +++++++++++++++++++++++++++++++
 drivers/net/dsa/qca/qca8k.h      |  69 +++++++++++
 5 files changed, 279 insertions(+)
 create mode 100644 drivers/net/dsa/qca/qca8k-leds.c

Comments

Andrew Lunn March 10, 2023, 12:12 a.m. UTC | #1
> +config NET_DSA_QCA8K_LEDS_SUPPORT
> +	tristate "Qualcomm Atheros QCA8K Ethernet switch family LEDs support"

Is tristate correct here? That means the code can either be built in,
a module, or not built at all. Is that what you want?

It seems more normal to use a bool, not a tristate.

> +static enum led_brightness
> +qca8k_led_brightness_get(struct qca8k_led *led)
> +{
> +	struct qca8k_led_pattern_en reg_info;
> +	struct qca8k_priv *priv = led->priv;
> +	u32 val;
> +	int ret;
> +
> +	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
> +
> +	ret = regmap_read(priv->regmap, reg_info.reg, &val);
> +	if (ret)
> +		return 0;
> +
> +	val >>= reg_info.shift;
> +
> +	if (led->port_num == 0 || led->port_num == 4) {
> +		val &= QCA8K_LED_PATTERN_EN_MASK;
> +		val >>= QCA8K_LED_PATTERN_EN_SHIFT;
> +	} else {
> +		val &= QCA8K_LED_PHY123_PATTERN_EN_MASK;
> +	}
> +
> +	return val > 0 ? 1 : 0;
> +}

What will this return when in the future you add hardware offload, and
the LED is actually blinking because of frames being sent etc?

Is it better to not implement _get() when it is unclear what it should
return when offload is in operation?

       Andrew
Christian Marangi March 10, 2023, 12:18 a.m. UTC | #2
On Fri, Mar 10, 2023 at 01:12:03AM +0100, Andrew Lunn wrote:
> > +config NET_DSA_QCA8K_LEDS_SUPPORT
> > +	tristate "Qualcomm Atheros QCA8K Ethernet switch family LEDs support"
> 
> Is tristate correct here? That means the code can either be built in,
> a module, or not built at all. Is that what you want?
> 
> It seems more normal to use a bool, not a tristate.
>

Think you are right, can't really be a module.

> > +static enum led_brightness
> > +qca8k_led_brightness_get(struct qca8k_led *led)
> > +{
> > +	struct qca8k_led_pattern_en reg_info;
> > +	struct qca8k_priv *priv = led->priv;
> > +	u32 val;
> > +	int ret;
> > +
> > +	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
> > +
> > +	ret = regmap_read(priv->regmap, reg_info.reg, &val);
> > +	if (ret)
> > +		return 0;
> > +
> > +	val >>= reg_info.shift;
> > +
> > +	if (led->port_num == 0 || led->port_num == 4) {
> > +		val &= QCA8K_LED_PATTERN_EN_MASK;
> > +		val >>= QCA8K_LED_PATTERN_EN_SHIFT;
> > +	} else {
> > +		val &= QCA8K_LED_PHY123_PATTERN_EN_MASK;
> > +	}
> > +
> > +	return val > 0 ? 1 : 0;
> > +}
> 
> What will this return when in the future you add hardware offload, and
> the LED is actually blinking because of frames being sent etc?
> 
> Is it better to not implement _get() when it is unclear what it should
> return when offload is in operation?
> 
>        Andrew

My idea was that anything that is not 'always off' will have brightness
1. So also in accelerated blink brightness should be 1.

My idea of get was that it should reflect if the led is active or always
off. Is it wrong?
Andrew Lunn March 10, 2023, 12:58 a.m. UTC | #3
> > > +static enum led_brightness
> > > +qca8k_led_brightness_get(struct qca8k_led *led)
> > > +{
> > > +	struct qca8k_led_pattern_en reg_info;
> > > +	struct qca8k_priv *priv = led->priv;
> > > +	u32 val;
> > > +	int ret;
> > > +
> > > +	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
> > > +
> > > +	ret = regmap_read(priv->regmap, reg_info.reg, &val);
> > > +	if (ret)
> > > +		return 0;
> > > +
> > > +	val >>= reg_info.shift;
> > > +
> > > +	if (led->port_num == 0 || led->port_num == 4) {
> > > +		val &= QCA8K_LED_PATTERN_EN_MASK;
> > > +		val >>= QCA8K_LED_PATTERN_EN_SHIFT;
> > > +	} else {
> > > +		val &= QCA8K_LED_PHY123_PATTERN_EN_MASK;
> > > +	}
> > > +
> > > +	return val > 0 ? 1 : 0;
> > > +}
> > 
> > What will this return when in the future you add hardware offload, and
> > the LED is actually blinking because of frames being sent etc?
> > 
> > Is it better to not implement _get() when it is unclear what it should
> > return when offload is in operation?
> > 
> 
> My idea was that anything that is not 'always off' will have brightness
> 1. So also in accelerated blink brightness should be 1.
> 
> My idea of get was that it should reflect if the led is active or always
> off. Is it wrong?
 
brigntness_get seems to be used in two situations:

When the LED is first registered, it can be called to get the current
state of the LED. This then initialized cdev->brightness.

When the brightness sysfs file is read, there is first a call to
brightness_get to allow it to update the value in cdev->brightness
before returning the value in the read.

I think always returning 1 could be confusing. Take the example that
the LED is indicating link, there is no link, so it is off. Yet a read
of the brightness sysfs file will return 1?

I would say, it either needs to return the instantaneous brightness,
or it should not be implemented at all. When we come to implement
offloading, we might want to consider hiding the brightness sysfs
file. But we can solve that later.

      Andrew
diff mbox series

Patch

diff --git a/drivers/net/dsa/qca/Kconfig b/drivers/net/dsa/qca/Kconfig
index ba339747362c..dab648f88391 100644
--- a/drivers/net/dsa/qca/Kconfig
+++ b/drivers/net/dsa/qca/Kconfig
@@ -15,3 +15,10 @@  config NET_DSA_QCA8K
 	help
 	  This enables support for the Qualcomm Atheros QCA8K Ethernet
 	  switch chips.
+
+config NET_DSA_QCA8K_LEDS_SUPPORT
+	tristate "Qualcomm Atheros QCA8K Ethernet switch family LEDs support"
+	depends on NET_DSA_QCA8K
+	help
+	  This enabled support for LEDs present on the Qualcomm Atheros
+	  QCA8K Ethernet switch chips.
diff --git a/drivers/net/dsa/qca/Makefile b/drivers/net/dsa/qca/Makefile
index 701f1d199e93..330ae389e489 100644
--- a/drivers/net/dsa/qca/Makefile
+++ b/drivers/net/dsa/qca/Makefile
@@ -2,3 +2,4 @@ 
 obj-$(CONFIG_NET_DSA_AR9331)	+= ar9331.o
 obj-$(CONFIG_NET_DSA_QCA8K)	+= qca8k.o
 qca8k-y 			+= qca8k-common.o qca8k-8xxx.o
+obj-$(CONFIG_NET_DSA_QCA8K_LEDS_SUPPORT) += qca8k-leds.o
diff --git a/drivers/net/dsa/qca/qca8k-8xxx.c b/drivers/net/dsa/qca/qca8k-8xxx.c
index 8dfc5db84700..fe68ac7e4030 100644
--- a/drivers/net/dsa/qca/qca8k-8xxx.c
+++ b/drivers/net/dsa/qca/qca8k-8xxx.c
@@ -1727,6 +1727,10 @@  qca8k_setup(struct dsa_switch *ds)
 	if (ret)
 		return ret;
 
+	ret = qca8k_setup_led_ctrl(priv);
+	if (ret)
+		return ret;
+
 	qca8k_setup_pcs(priv, &priv->pcs_port_0, 0);
 	qca8k_setup_pcs(priv, &priv->pcs_port_6, 6);
 
diff --git a/drivers/net/dsa/qca/qca8k-leds.c b/drivers/net/dsa/qca/qca8k-leds.c
new file mode 100644
index 000000000000..7ae2ea082aae
--- /dev/null
+++ b/drivers/net/dsa/qca/qca8k-leds.c
@@ -0,0 +1,198 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/regmap.h>
+#include <net/dsa.h>
+
+#include "qca8k.h"
+
+static int
+qca8k_get_enable_led_reg(int port_num, int led_num, struct qca8k_led_pattern_en *reg_info)
+{
+	switch (port_num) {
+	case 0:
+		reg_info->reg = QCA8K_LED_CTRL_REG(led_num);
+		reg_info->shift = QCA8K_LED_PHY0123_CONTROL_RULE_SHIFT;
+		break;
+	case 1:
+	case 2:
+	case 3:
+		/* Port 123 are controlled on a different reg */
+		reg_info->reg = QCA8K_LED_CTRL_REG(3);
+		reg_info->shift = QCA8K_LED_PHY123_PATTERN_EN_SHIFT(port_num, led_num);
+		break;
+	case 4:
+		reg_info->reg = QCA8K_LED_CTRL_REG(led_num);
+		reg_info->shift = QCA8K_LED_PHY4_CONTROL_RULE_SHIFT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int
+qca8k_led_brightness_set(struct qca8k_led *led,
+			 enum led_brightness brightness)
+{
+	struct qca8k_led_pattern_en reg_info;
+	struct qca8k_priv *priv = led->priv;
+	u32 mask, val = QCA8K_LED_ALWAYS_OFF;
+
+	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
+
+	if (brightness)
+		val = QCA8K_LED_ALWAYS_ON;
+
+	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;
+	}
+
+	return regmap_update_bits(priv->regmap, reg_info.reg,
+				  mask << reg_info.shift,
+				  val << reg_info.shift);
+}
+
+static int
+qca8k_cled_brightness_set_blocking(struct led_classdev *ldev,
+				   enum led_brightness brightness)
+{
+	struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev);
+
+	return qca8k_led_brightness_set(led, brightness);
+}
+
+static enum led_brightness
+qca8k_led_brightness_get(struct qca8k_led *led)
+{
+	struct qca8k_led_pattern_en reg_info;
+	struct qca8k_priv *priv = led->priv;
+	u32 val;
+	int ret;
+
+	qca8k_get_enable_led_reg(led->port_num, led->led_num, &reg_info);
+
+	ret = regmap_read(priv->regmap, reg_info.reg, &val);
+	if (ret)
+		return 0;
+
+	val >>= reg_info.shift;
+
+	if (led->port_num == 0 || led->port_num == 4) {
+		val &= QCA8K_LED_PATTERN_EN_MASK;
+		val >>= QCA8K_LED_PATTERN_EN_SHIFT;
+	} else {
+		val &= QCA8K_LED_PHY123_PATTERN_EN_MASK;
+	}
+
+	return val > 0 ? 1 : 0;
+}
+
+static enum led_brightness
+qca8k_cled_brightness_get(struct led_classdev *ldev)
+{
+	struct qca8k_led *led = container_of(ldev, struct qca8k_led, cdev);
+
+	return qca8k_led_brightness_get(led);
+}
+
+static int
+qca8k_parse_port_leds(struct qca8k_priv *priv, struct fwnode_handle *port, int port_num)
+{
+	struct fwnode_handle *led = NULL, *leds = NULL;
+	struct led_init_data init_data = { };
+	struct qca8k_led *port_led;
+	int led_num, port_index;
+	const char *state;
+	int ret;
+
+	leds = fwnode_get_named_child_node(port, "leds");
+	if (!leds) {
+		dev_dbg(priv->dev, "No Leds node specified in device tree for port %d!\n",
+			port_num);
+		return 0;
+	}
+
+	fwnode_for_each_child_node(leds, led) {
+		/* Reg represent the led number of the port.
+		 * Each port can have at least 3 leds attached
+		 * Commonly:
+		 * 1. is gigabit led
+		 * 2. is mbit led
+		 * 3. additional status led
+		 */
+		if (fwnode_property_read_u32(led, "reg", &led_num))
+			continue;
+
+		if (led_num >= QCA8K_LED_PORT_COUNT) {
+			dev_warn(priv->dev, "Invalid LED reg defined %d", port_num);
+			continue;
+		}
+
+		port_index = 3 * port_num + led_num;
+
+		port_led = &priv->ports_led[port_index];
+		port_led->port_num = port_num;
+		port_led->led_num = led_num;
+		port_led->priv = priv;
+
+		ret = fwnode_property_read_string(led, "default-state", &state);
+		if (!ret) {
+			if (!strcmp(state, "on")) {
+				port_led->cdev.brightness = 1;
+				qca8k_led_brightness_set(port_led, 1);
+			} else if (!strcmp(state, "off")) {
+				port_led->cdev.brightness = 0;
+				qca8k_led_brightness_set(port_led, 0);
+			} else if (!strcmp(state, "keep")) {
+				port_led->cdev.brightness =
+					qca8k_led_brightness_get(port_led);
+			}
+		}
+
+		port_led->cdev.max_brightness = 1;
+		port_led->cdev.brightness_set_blocking = qca8k_cled_brightness_set_blocking;
+		port_led->cdev.brightness_get = qca8k_cled_brightness_get;
+		init_data.default_label = ":port";
+		init_data.devicename = "qca8k";
+		init_data.fwnode = led;
+
+		ret = devm_led_classdev_register_ext(priv->dev, &port_led->cdev, &init_data);
+		if (ret)
+			dev_warn(priv->dev, "Failed to int led");
+	}
+
+	return 0;
+}
+
+int
+qca8k_setup_led_ctrl(struct qca8k_priv *priv)
+{
+	struct fwnode_handle *ports, *port;
+	int port_num;
+	int ret;
+
+	ports = device_get_named_child_node(priv->dev, "ports");
+	if (!ports) {
+		dev_info(priv->dev, "No ports node specified in device tree!\n");
+		return 0;
+	}
+
+	fwnode_for_each_child_node(ports, port) {
+		if (fwnode_property_read_u32(port, "reg", &port_num))
+			continue;
+
+		/* Each port can have at least 3 different leds attached.
+		 * Switch port starts from 0 to 6, but port 0 and 6 are CPU
+		 * port. The port index needs to be decreased by one to identify
+		 * the correct port for LED setup.
+		 */
+		ret = qca8k_parse_port_leds(priv, port, qca8k_port_to_phy(port_num));
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
diff --git a/drivers/net/dsa/qca/qca8k.h b/drivers/net/dsa/qca/qca8k.h
index 4e48e4dd8b0f..25fab385f0f7 100644
--- a/drivers/net/dsa/qca/qca8k.h
+++ b/drivers/net/dsa/qca/qca8k.h
@@ -11,6 +11,7 @@ 
 #include <linux/delay.h>
 #include <linux/regmap.h>
 #include <linux/gpio.h>
+#include <linux/leds.h>
 #include <linux/dsa/tag_qca.h>
 
 #define QCA8K_ETHERNET_MDIO_PRIORITY			7
@@ -85,6 +86,50 @@ 
 #define   QCA8K_MDIO_MASTER_DATA(x)			FIELD_PREP(QCA8K_MDIO_MASTER_DATA_MASK, x)
 #define   QCA8K_MDIO_MASTER_MAX_PORTS			5
 #define   QCA8K_MDIO_MASTER_MAX_REG			32
+
+/* LED control register */
+#define QCA8K_LED_COUNT					15
+#define QCA8K_LED_PORT_COUNT				3
+#define QCA8K_LED_RULE_COUNT				6
+#define QCA8K_LED_RULE_MAX				11
+
+#define QCA8K_LED_PHY123_PATTERN_EN_SHIFT(_phy, _led)	((((_phy) - 1) * 6) + 8 + (2 * (_led)))
+#define QCA8K_LED_PHY123_PATTERN_EN_MASK		GENMASK(1, 0)
+
+#define QCA8K_LED_PHY0123_CONTROL_RULE_SHIFT		0
+#define QCA8K_LED_PHY4_CONTROL_RULE_SHIFT		16
+
+#define QCA8K_LED_CTRL_REG(_i)				(0x050 + (_i) * 4)
+#define QCA8K_LED_CTRL0_REG				0x50
+#define QCA8K_LED_CTRL1_REG				0x54
+#define QCA8K_LED_CTRL2_REG				0x58
+#define QCA8K_LED_CTRL3_REG				0x5C
+#define   QCA8K_LED_CTRL_SHIFT(_i)			(((_i) % 2) * 16)
+#define   QCA8K_LED_CTRL_MASK				GENMASK(15, 0)
+#define QCA8K_LED_RULE_MASK				GENMASK(13, 0)
+#define QCA8K_LED_BLINK_FREQ_MASK			GENMASK(1, 0)
+#define QCA8K_LED_BLINK_FREQ_SHITF			0
+#define   QCA8K_LED_BLINK_2HZ				0
+#define   QCA8K_LED_BLINK_4HZ				1
+#define   QCA8K_LED_BLINK_8HZ				2
+#define   QCA8K_LED_BLINK_AUTO				3
+#define QCA8K_LED_LINKUP_OVER_MASK			BIT(2)
+#define QCA8K_LED_TX_BLINK_MASK				BIT(4)
+#define QCA8K_LED_RX_BLINK_MASK				BIT(5)
+#define QCA8K_LED_COL_BLINK_MASK			BIT(7)
+#define QCA8K_LED_LINK_10M_EN_MASK			BIT(8)
+#define QCA8K_LED_LINK_100M_EN_MASK			BIT(9)
+#define QCA8K_LED_LINK_1000M_EN_MASK			BIT(10)
+#define QCA8K_LED_POWER_ON_LIGHT_MASK			BIT(11)
+#define QCA8K_LED_HALF_DUPLEX_MASK			BIT(12)
+#define QCA8K_LED_FULL_DUPLEX_MASK			BIT(13)
+#define QCA8K_LED_PATTERN_EN_MASK			GENMASK(15, 14)
+#define QCA8K_LED_PATTERN_EN_SHIFT			14
+#define   QCA8K_LED_ALWAYS_OFF				0
+#define   QCA8K_LED_ALWAYS_BLINK_4HZ			1
+#define   QCA8K_LED_ALWAYS_ON				2
+#define   QCA8K_LED_RULE_CONTROLLED			3
+
 #define QCA8K_GOL_MAC_ADDR0				0x60
 #define QCA8K_GOL_MAC_ADDR1				0x64
 #define QCA8K_MAX_FRAME_SIZE				0x78
@@ -383,6 +428,19 @@  struct qca8k_pcs {
 	int port;
 };
 
+struct qca8k_led_pattern_en {
+	u32 reg;
+	u8 shift;
+};
+
+struct qca8k_led {
+	u8 port_num;
+	u8 led_num;
+	u16 old_rule;
+	struct qca8k_priv *priv;
+	struct led_classdev cdev;
+};
+
 struct qca8k_priv {
 	u8 switch_id;
 	u8 switch_revision;
@@ -407,6 +465,7 @@  struct qca8k_priv {
 	struct qca8k_pcs pcs_port_0;
 	struct qca8k_pcs pcs_port_6;
 	const struct qca8k_match_data *info;
+	struct qca8k_led ports_led[QCA8K_LED_COUNT];
 };
 
 struct qca8k_mib_desc {
@@ -526,4 +585,14 @@  int qca8k_port_lag_join(struct dsa_switch *ds, int port, struct dsa_lag lag,
 int qca8k_port_lag_leave(struct dsa_switch *ds, int port,
 			 struct dsa_lag lag);
 
+/* Leds Support function */
+#ifdef CONFIG_NET_DSA_QCA8K_LEDS_SUPPORT
+int qca8k_setup_led_ctrl(struct qca8k_priv *priv);
+#else
+static inline int qca8k_setup_led_ctrl(struct qca8k_priv *priv)
+{
+	return 0;
+}
+#endif
+
 #endif /* __QCA8K_H */