scsi: qla2xxx: Add beacon LED config sysfs interface

This patch provides an interface to do the following (using MBC 0x3B):

 - Displays (in hex) the LED config words for all three LEDs.

 - Programs the config words for one LED or for all three LEDs.

The sysfs node defined is named beacon_config.

First, to allow driver to gain LED control, do this:
 # echo 1 > /sys/class/scsi_host/host#/beacon

Then, to display config words for all three LEDs do this:
 # cat /sys/class/scsi_host/host#/beacon_config

To set config words for all three LEDs do this:
 # echo 3 xxxx yyyy zzzz > /sys/class/scsi_host/host#/beacon_config

Or, to set config word for a specific single LED n do this:
 # echo n xxxx > /sys/class/scsi_host/host#/beacon_config
  where n is the LED number (0, 1, 2)

Finally, to restore LED control back to firmware, do this:
 # echo 0 > /sys/class/scsi_host/host#/beacon

Link: https://lore.kernel.org/r/20200212214436.25532-2-hmadhani@marvell.com
Signed-off-by: Joe Carnuccio <joe.carnuccio@cavium.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_attr.c

@@ -1323,6 +1323,79 @@ qla2x00_beacon_store(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
+static ssize_t
+qla2x00_beacon_config_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	scsi_qla_host_t *vha = shost_priv(class_to_shost(dev));
+	struct qla_hw_data *ha = vha->hw;
+	uint16_t led[3] = { 0 };
+
+	if (!IS_QLA2031(ha) && !IS_QLA27XX(ha) && !IS_QLA28XX(ha))
+		return -EPERM;
+
+	if (ql26xx_led_config(vha, 0, led))
+		return scnprintf(buf, PAGE_SIZE, "\n");
+
+	return scnprintf(buf, PAGE_SIZE, "%#04hx %#04hx %#04hx\n",
+	    led[0], led[1], led[2]);
+}
+
+static ssize_t
+qla2x00_beacon_config_store(struct device *dev, struct device_attribute *attr,
+	const char *buf, size_t count)
+{
+	scsi_qla_host_t *vha = shost_priv(class_to_shost(dev));
+	struct qla_hw_data *ha = vha->hw;
+	uint16_t options = BIT_0;
+	uint16_t led[3] = { 0 };
+	uint16_t word[4];
+	int n;
+
+	if (!IS_QLA2031(ha) && !IS_QLA27XX(ha) && !IS_QLA28XX(ha))
+		return -EPERM;
+
+	n = sscanf(buf, "%hx %hx %hx %hx", word+0, word+1, word+2, word+3);
+	if (n == 4) {
+		if (word[0] == 3) {
+			options |= BIT_3|BIT_2|BIT_1;
+			led[0] = word[1];
+			led[1] = word[2];
+			led[2] = word[3];
+			goto write;
+		}
+		return -EINVAL;
+	}
+
+	if (n == 2) {
+		/* check led index */
+		if (word[0] == 0) {
+			options |= BIT_2;
+			led[0] = word[1];
+			goto write;
+		}
+		if (word[0] == 1) {
+			options |= BIT_3;
+			led[1] = word[1];
+			goto write;
+		}
+		if (word[0] == 2) {
+			options |= BIT_1;
+			led[2] = word[1];
+			goto write;
+		}
+		return -EINVAL;
+	}
+
+	return -EINVAL;
+
+write:
+	if (ql26xx_led_config(vha, options, led))
+		return -EFAULT;
+
+	return count;
+}
+
 static ssize_t
 qla2x00_optrom_bios_version_show(struct device *dev,
 				 struct device_attribute *attr, char *buf)
@@ -2264,6 +2337,8 @@ static DEVICE_ATTR(zio_timer, S_IRUGO | S_IWUSR, qla2x00_zio_timer_show,
 		   qla2x00_zio_timer_store);
 static DEVICE_ATTR(beacon, S_IRUGO | S_IWUSR, qla2x00_beacon_show,
 		   qla2x00_beacon_store);
+static DEVICE_ATTR(beacon_config, 0644, qla2x00_beacon_config_show,
+		   qla2x00_beacon_config_store);
 static DEVICE_ATTR(optrom_bios_version, S_IRUGO,
 		   qla2x00_optrom_bios_version_show, NULL);
 static DEVICE_ATTR(optrom_efi_version, S_IRUGO,
@@ -2327,6 +2402,7 @@ struct device_attribute *qla2x00_host_attrs[] = {
 	&dev_attr_zio,
 	&dev_attr_zio_timer,
 	&dev_attr_beacon,
+	&dev_attr_beacon_config,
 	&dev_attr_optrom_bios_version,
 	&dev_attr_optrom_efi_version,
 	&dev_attr_optrom_fcode_version,

drivers/scsi/qla2xxx/qla_def.h

@@ -1134,6 +1134,7 @@ static inline bool qla2xxx_is_valid_mbs(unsigned int mbs)
 #define MBC_GET_FIRMWARE_OPTION		0x28	/* Get Firmware Options. */
 #define MBC_GET_MEM_OFFLOAD_CNTRL_STAT	0x34	/* Memory Offload ctrl/Stat*/
 #define MBC_SET_FIRMWARE_OPTION		0x38	/* Set Firmware Options. */
+#define MBC_SET_GET_FC_LED_CONFIG	0x3b	/* Set/Get FC LED config */
 #define MBC_LOOP_PORT_BYPASS		0x40	/* Loop Port Bypass. */
 #define MBC_LOOP_PORT_ENABLE		0x41	/* Loop Port Enable. */
 #define MBC_GET_RESOURCE_COUNTS		0x42	/* Get Resource Counts. */

drivers/scsi/qla2xxx/qla_gbl.h

@@ -844,6 +844,7 @@ extern void qla82xx_clear_pending_mbx(scsi_qla_host_t *);
 extern int qla82xx_read_temperature(scsi_qla_host_t *);
 extern int qla8044_read_temperature(scsi_qla_host_t *);
 extern int qla2x00_read_sfp_dev(struct scsi_qla_host *, char *, int);
+extern int ql26xx_led_config(scsi_qla_host_t *, uint16_t, uint16_t *);
 
 /* BSG related functions */
 extern int qla24xx_bsg_request(struct bsg_job *);

drivers/scsi/qla2xxx/qla_mbx.c

@@ -6688,3 +6688,60 @@ int qla2xxx_read_remote_register(scsi_qla_host_t *vha, uint32_t addr,
 
 	return rval;
 }
+
+int
+ql26xx_led_config(scsi_qla_host_t *vha, uint16_t options, uint16_t *led)
+{
+	struct qla_hw_data *ha = vha->hw;
+	mbx_cmd_t mc;
+	mbx_cmd_t *mcp = &mc;
+	int rval;
+
+	if (!IS_QLA2031(ha) && !IS_QLA27XX(ha) && !IS_QLA28XX(ha))
+		return QLA_FUNCTION_FAILED;
+
+	ql_dbg(ql_dbg_mbx, vha, 0x7070, "Entered %s (options=%x).\n",
+	    __func__, options);
+
+	mcp->mb[0] = MBC_SET_GET_FC_LED_CONFIG;
+	mcp->mb[1] = options;
+	mcp->out_mb = MBX_1|MBX_0;
+	mcp->in_mb = MBX_1|MBX_0;
+	if (options & BIT_0) {
+		if (options & BIT_1) {
+			mcp->mb[2] = led[2];
+			mcp->out_mb |= MBX_2;
+		}
+		if (options & BIT_2) {
+			mcp->mb[3] = led[0];
+			mcp->out_mb |= MBX_3;
+		}
+		if (options & BIT_3) {
+			mcp->mb[4] = led[1];
+			mcp->out_mb |= MBX_4;
+		}
+	} else {
+		mcp->in_mb |= MBX_4|MBX_3|MBX_2;
+	}
+	mcp->tov = MBX_TOV_SECONDS;
+	mcp->flags = 0;
+	rval = qla2x00_mailbox_command(vha, mcp);
+	if (rval) {
+		ql_dbg(ql_dbg_mbx, vha, 0x7071, "Failed %s %x (mb=%x,%x)\n",
+		    __func__, rval, mcp->mb[0], mcp->mb[1]);
+		return rval;
+	}
+
+	if (options & BIT_0) {
+		ha->beacon_blink_led = 0;
+		ql_dbg(ql_dbg_mbx, vha, 0x7072, "Done %s\n", __func__);
+	} else {
+		led[2] = mcp->mb[2];
+		led[0] = mcp->mb[3];
+		led[1] = mcp->mb[4];
+		ql_dbg(ql_dbg_mbx, vha, 0x7073, "Done %s (led=%x,%x,%x)\n",
+		    __func__, led[0], led[1], led[2]);
+	}
+
+	return rval;
+}