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@@ -1,32 +1,15 @@
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Kernel driver for the NXP Semiconductors PN544 Near Field
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Communication chip
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-Author: Jari Vanhala
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-Contact: Matti Aaltonen (matti.j.aaltonen at nokia.com)
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-
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General
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-------
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The PN544 is an integrated transmission module for contactless
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communication. The driver goes under drives/nfc/ and is compiled as a
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-module named "pn544". It registers a misc device and creates a device
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-file named "/dev/pn544".
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+module named "pn544".
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Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C.
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-The Interface
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--------------
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-
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-The driver offers a sysfs interface for a hardware test and an IOCTL
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-interface for selecting between two operating modes. There are read,
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-write and poll functions for transferring messages. The two operating
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-modes are the normal (HCI) mode and the firmware update mode.
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-
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-PN544 is controlled by sending messages from the userspace to the
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-chip. The main function of the driver is just to pass those messages
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-without caring about the message content.
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-
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-
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Protocols
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---------
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@@ -47,68 +30,3 @@ and third (LSB) bytes of the message. The maximum FW message length is
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For the ETSI HCI specification see
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http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx
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-
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-The Hardware Test
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------------------
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-
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-The idea of the test is that it can performed by reading from the
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-corresponding sysfs file. The test is implemented in the board file
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-and it should test that PN544 can be put into the firmware update
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-mode. If the test is not implemented the sysfs file does not get
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-created.
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-
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-Example:
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-> cat /sys/module/pn544/drivers/i2c\:pn544/3-002b/nfc_test
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-1
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-
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-Normal Operation
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-----------------
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-
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-PN544 is powered up when the device file is opened, otherwise it's
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-turned off. Only one instance can use the device at a time.
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-
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-Userspace applications control PN544 with HCI messages. The hardware
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-sends an interrupt when data is available for reading. Data is
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-physically read when the read function is called by a userspace
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-application. Poll() checks the read interrupt state. Configuration and
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-self testing are also done from the userspace using read and write.
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-
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-Example platform data:
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-
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-static int rx71_pn544_nfc_request_resources(struct i2c_client *client)
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-{
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- /* Get and setup the HW resources for the device */
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-}
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-
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-static void rx71_pn544_nfc_free_resources(void)
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-{
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- /* Release the HW resources */
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-}
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-
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-static void rx71_pn544_nfc_enable(int fw)
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-{
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- /* Turn the device on */
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-}
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-
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-static int rx71_pn544_nfc_test(void)
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-{
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- /*
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- * Put the device into the FW update mode
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- * and then back to the normal mode.
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- * Check the behavior and return one on success,
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- * zero on failure.
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- */
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-}
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-
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-static void rx71_pn544_nfc_disable(void)
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-{
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- /* turn the power off */
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-}
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-
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-static struct pn544_nfc_platform_data rx71_nfc_data = {
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- .request_resources = rx71_pn544_nfc_request_resources,
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- .free_resources = rx71_pn544_nfc_free_resources,
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- .enable = rx71_pn544_nfc_enable,
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- .test = rx71_pn544_nfc_test,
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- .disable = rx71_pn544_nfc_disable,
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-};
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Samuel Ortiz