diff --git a/Documentation/pcmcia/driver.txt b/Documentation/pcmcia/driver.txt
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+PCMCIA Driver
+-------------
+
+
+sysfs
+-----
+
+New PCMCIA IDs may be added to a device driver pcmcia_device_id table at
+runtime as shown below:
+
+echo "match_flags manf_id card_id func_id function device_no \
+prod_id_hash[0] prod_id_hash[1] prod_id_hash[2] prod_id_hash[3]" > \
+/sys/bus/pcmcia/drivers/{driver}/new_id
+
+All fields are passed in as hexadecimal values (no leading 0x).
+The meaning is described in the PCMCIA specification, the match_flags is
+a bitwise or-ed combination from PCMCIA_DEV_ID_MATCH_* constants
+defined in include/linux/mod_devicetable.h.
+
+Once added, the driver probe routine will be invoked for any unclaimed
+PCMCIA device listed in its (newly updated) pcmcia_device_id list.
+
+A common use-case is to add a new device according to the manufacturer ID
+and the card ID (form the manf_id and card_id file in the device tree).
+For this, just use:
+
+echo "0x3 manf_id card_id 0 0 0 0 0 0 0" > \
+        /sys/bus/pcmcia/drivers/{driver}/new_id
+
+after loading the driver.