igc: Export LEDs

Each i225 has three LEDs. Export them via the LED class framework.

Each LED is controllable via sysfs. Example:

$ cd /sys/class/leds/igc_led0
$ cat brightness      # Current Mode
$ cat max_brightness  # 15
$ echo 0 > brightness # Mode 0
$ echo 1 > brightness # Mode 1

The brightness field here reflects the different LED modes ranging
from 0 to 15.
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/Kconfig

@@ -335,6 +335,7 @@ config IGC
 	tristate "Intel(R) Ethernet Controller I225-LM/I225-V support"
 	default n
 	depends on PCI
+	depends on LEDS_CLASS
 	help
 	  This driver supports Intel(R) Ethernet Controller I225-LM/I225-V
 	  family of adapters.

drivers/net/ethernet/intel/igc/igc.h

@@ -13,6 +13,7 @@
 #include <linux/ptp_clock_kernel.h>
 #include <linux/timecounter.h>
 #include <linux/net_tstamp.h>
+#include <linux/leds.h>
 
 #include "igc_hw.h"
 
@@ -239,8 +240,17 @@ struct igc_adapter {
 		struct timespec64 start;
 		struct timespec64 period;
 	} perout[IGC_N_PEROUT];
+
+	/* LEDs */
+	struct mutex led_mutex;
+	struct led_classdev led0;
+	struct led_classdev led1;
+	struct led_classdev led2;
 };
 
+#define led_to_igc(ldev, led)                          \
+	container_of(ldev, struct igc_adapter, led)
+
 void igc_up(struct igc_adapter *adapter);
 void igc_down(struct igc_adapter *adapter);
 int igc_open(struct net_device *netdev);

drivers/net/ethernet/intel/igc/igc_defines.h

@@ -144,6 +144,16 @@
 #define IGC_CTRL_SDP0_DIR	0x00400000  /* SDP0 Data direction */
 #define IGC_CTRL_SDP1_DIR	0x00800000  /* SDP1 Data direction */
 
+/* LED Control */
+#define IGC_LEDCTL_LED0_MODE_SHIFT	0
+#define IGC_LEDCTL_LED0_MODE_MASK	GENMASK(3, 0)
+#define IGC_LEDCTL_LED1_MODE_SHIFT	8
+#define IGC_LEDCTL_LED1_MODE_MASK	GENMASK(11, 8)
+#define IGC_LEDCTL_LED2_MODE_SHIFT	16
+#define IGC_LEDCTL_LED2_MODE_MASK	GENMASK(19, 16)
+
+#define IGC_CONNSW_AUTOSENSE_EN		0x1
+
 /* As per the EAS the maximum supported size is 9.5KB (9728 bytes) */
 #define MAX_JUMBO_FRAME_SIZE	0x2600
 

drivers/net/ethernet/intel/igc/igc_main.c

@@ -6130,6 +6130,134 @@ int igc_set_spd_dplx(struct igc_adapter *adapter, u32 spd, u8 dplx)
 	return -EINVAL;
 }
 
+static void igc_select_led(struct igc_adapter *adapter, int led,
+			   u32 *mask, u32 *shift)
+{
+	switch (led) {
+	case 0:
+		*mask  = IGC_LEDCTL_LED0_MODE_MASK;
+		*shift = IGC_LEDCTL_LED0_MODE_SHIFT;
+		break;
+	case 1:
+		*mask  = IGC_LEDCTL_LED1_MODE_MASK;
+		*shift = IGC_LEDCTL_LED1_MODE_SHIFT;
+		break;
+	case 2:
+		*mask  = IGC_LEDCTL_LED2_MODE_MASK;
+		*shift = IGC_LEDCTL_LED2_MODE_SHIFT;
+		break;
+	default:
+		*mask = *shift = 0;
+		dev_err(&adapter->pdev->dev, "Unknown led %d selected!", led);
+	}
+}
+
+static void igc_led_set(struct igc_adapter *adapter, int led, u16 brightness)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 shift, mask, ledctl;
+
+	igc_select_led(adapter, led, &mask, &shift);
+
+	mutex_lock(&adapter->led_mutex);
+	ledctl = rd32(IGC_LEDCTL);
+	ledctl &= ~mask;
+	ledctl |= brightness << shift;
+	wr32(IGC_LEDCTL, ledctl);
+	mutex_unlock(&adapter->led_mutex);
+}
+
+static enum led_brightness igc_led_get(struct igc_adapter *adapter, int led)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 shift, mask, ledctl;
+
+	igc_select_led(adapter, led, &mask, &shift);
+
+	mutex_lock(&adapter->led_mutex);
+	ledctl = rd32(IGC_LEDCTL);
+	mutex_unlock(&adapter->led_mutex);
+
+	return (ledctl & mask) >> shift;
+}
+
+static void igc_led0_set(struct led_classdev *ldev, enum led_brightness b)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led0);
+
+	igc_led_set(adapter, 0, b);
+}
+
+static enum led_brightness igc_led0_get(struct led_classdev *ldev)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led0);
+
+	return igc_led_get(adapter, 0);
+}
+
+static void igc_led1_set(struct led_classdev *ldev, enum led_brightness b)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led1);
+
+	igc_led_set(adapter, 1, b);
+}
+
+static enum led_brightness igc_led1_get(struct led_classdev *ldev)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led1);
+
+	return igc_led_get(adapter, 1);
+}
+
+static void igc_led2_set(struct led_classdev *ldev, enum led_brightness b)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led2);
+
+	igc_led_set(adapter, 2, b);
+}
+
+static enum led_brightness igc_led2_get(struct led_classdev *ldev)
+{
+	struct igc_adapter *adapter = led_to_igc(ldev, led2);
+
+	return igc_led_get(adapter, 2);
+}
+
+static int igc_led_setup(struct igc_adapter *adapter)
+{
+	/* Setup */
+	mutex_init(&adapter->led_mutex);
+
+	adapter->led0.name	     = "igc_led0";
+	adapter->led0.max_brightness = 15;
+	adapter->led0.brightness_set = igc_led0_set;
+	adapter->led0.brightness_get = igc_led0_get;
+
+	adapter->led1.name	     = "igc_led1";
+	adapter->led1.max_brightness = 15;
+	adapter->led1.brightness_set = igc_led1_set;
+	adapter->led1.brightness_get = igc_led1_get;
+
+	adapter->led2.name	     = "igc_led2";
+	adapter->led2.max_brightness = 15;
+	adapter->led2.brightness_set = igc_led2_set;
+	adapter->led2.brightness_get = igc_led2_get;
+
+	/* Register leds */
+	led_classdev_register(&adapter->pdev->dev, &adapter->led0);
+	led_classdev_register(&adapter->pdev->dev, &adapter->led1);
+	led_classdev_register(&adapter->pdev->dev, &adapter->led2);
+
+	return 0;
+}
+
+static void igc_led_destroy(struct igc_adapter *adapter)
+{
+	led_classdev_unregister(&adapter->led0);
+	led_classdev_unregister(&adapter->led1);
+	led_classdev_unregister(&adapter->led2);
+}
+
 /**
  * igc_probe - Device Initialization Routine
  * @pdev: PCI device information struct
@@ -6357,6 +6485,8 @@ static int igc_probe(struct pci_dev *pdev,
 
 	pm_runtime_put_noidle(&pdev->dev);
 
+	igc_led_setup(adapter);
+
 	return 0;
 
 err_register:
@@ -6398,6 +6528,8 @@ static void igc_remove(struct pci_dev *pdev)
 
 	igc_ptp_stop(adapter);
 
+	igc_led_destroy(adapter);
+
 	set_bit(__IGC_DOWN, &adapter->state);
 
 	del_timer_sync(&adapter->watchdog_timer);

drivers/net/ethernet/intel/igc/igc_regs.h

@@ -10,6 +10,8 @@
 #define IGC_EECD		0x00010  /* EEPROM/Flash Control - RW */
 #define IGC_CTRL_EXT		0x00018  /* Extended Device Control - RW */
 #define IGC_MDIC		0x00020  /* MDI Control - RW */
+#define IGC_LEDCTL		0x00E00	 /* LED Control - RW */
+#define IGC_MDICNFG		0x00E04  /* MDC/MDIO Configuration - RW */
 #define IGC_CONNSW		0x00034  /* Copper/Fiber switch control - RW */
 #define IGC_VET			0x00038  /* VLAN Ether Type - RW */
 #define IGC_I225_PHPM		0x00E14  /* I225 PHY Power Management */