1 files changed, 124 insertions, 0 deletions

diff --git a/include/linux/spi/spidev.h b/include/linux/spi/spidev.h
new file mode 100644
index 000000000000..7d700be57490
--- /dev/null
+++ b/include/linux/spi/spidev.h
@@ -0,0 +1,124 @@
+/*
+ * include/linux/spi/spidev.h
+ *
+ * Copyright (C) 2006 SWAPP
+ *      Andrea Paterniani <a.paterniani@swapp-eng.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+  */
+
+#ifndef SPIDEV_H
+#define SPIDEV_H
+
+
+/* User space versions of kernel symbols for SPI clocking modes,
+ * matching <linux/spi/spi.h>
+ */
+
+#define SPI_CPHA                0x01
+#define SPI_CPOL                0x02
+
+#define SPI_MODE_0              (0|0)
+#define SPI_MODE_1              (0|SPI_CPHA)
+#define SPI_MODE_2              (SPI_CPOL|0)
+#define SPI_MODE_3              (SPI_CPOL|SPI_CPHA)
+
+
+/*---------------------------------------------------------------------------*/
+
+/* IOCTL commands */
+
+#define SPI_IOC_MAGIC                   'k'
+
+/**
+ * struct spi_ioc_transfer - describes a single SPI transfer
+ * @tx_buf: Holds pointer to userspace buffer with transmit data, or null.
+ *      If no data is provided, zeroes are shifted out.
+ * @rx_buf: Holds pointer to userspace buffer for receive data, or null.
+ * @len: Length of tx and rx buffers, in bytes.
+ * @speed_hz: Temporary override of the device's bitrate.
+ * @bits_per_word: Temporary override of the device's wordsize.
+ * @delay_usecs: If nonzero, how long to delay after the last bit transfer
+ *      before optionally deselecting the device before the next transfer.
+ * @cs_change: True to deselect device before starting the next transfer.
+ *
+ * This structure is mapped directly to the kernel spi_transfer structure;
+ * the fields have the same meanings, except of course that the pointers
+ * are in a different address space (and may be of different sizes in some
+ * cases, such as 32-bit i386 userspace over a 64-bit x86_64 kernel).
+ * Zero-initialize the structure, including currently unused fields, to
+ * accomodate potential future updates.
+ *
+ * SPI_IOC_MESSAGE gives userspace the equivalent of kernel spi_sync().
+ * Pass it an array of related transfers, they'll execute together.
+ * Each transfer may be half duplex (either direction) or full duplex.
+ *
+ *      struct spi_ioc_transfer mesg[4];
+ *      ...
+ *      status = ioctl(fd, SPI_IOC_MESSAGE(4), mesg);
+ *
+ * So for example one transfer might send a nine bit command (right aligned
+ * in a 16-bit word), the next could read a block of 8-bit data before
+ * terminating that command by temporarily deselecting the chip; the next
+ * could send a different nine bit command (re-selecting the chip), and the
+ * last transfer might write some register values.
+ */
+struct spi_ioc_transfer {
+        __u64           tx_buf;
+        __u64           rx_buf;
+
+        __u32           len;
+        __u32           speed_hz;
+
+        __u16           delay_usecs;
+        __u8            bits_per_word;
+        __u8            cs_change;
+        __u32           pad;
+
+        /* If the contents of 'struct spi_ioc_transfer' ever change
+         * incompatibly, then the ioctl number (currently 0) must change;
+         * ioctls with constant size fields get a bit more in the way of
+         * error checking than ones (like this) where that field varies.
+         *
+         * NOTE: struct layout is the same in 64bit and 32bit userspace.
+         */
+};
+
+/* not all platforms use <asm-generic/ioctl.h> or _IOC_TYPECHECK() ... */
+#define SPI_MSGSIZE(N) \
+        ((((N)*(sizeof (struct spi_ioc_transfer))) < (1 << _IOC_SIZEBITS)) \
+                ? ((N)*(sizeof (struct spi_ioc_transfer))) : 0)
+#define SPI_IOC_MESSAGE(N) _IOW(SPI_IOC_MAGIC, 0, char[SPI_MSGSIZE(N)])
+
+
+/* Read / Write of SPI mode (SPI_MODE_0..SPI_MODE_3) */
+#define SPI_IOC_RD_MODE                 _IOR(SPI_IOC_MAGIC, 1, __u8)
+#define SPI_IOC_WR_MODE                 _IOW(SPI_IOC_MAGIC, 1, __u8)
+
+/* Read / Write SPI bit justification */
+#define SPI_IOC_RD_LSB_FIRST            _IOR(SPI_IOC_MAGIC, 2, __u8)
+#define SPI_IOC_WR_LSB_FIRST            _IOW(SPI_IOC_MAGIC, 2, __u8)
+
+/* Read / Write SPI device word length (1..N) */
+#define SPI_IOC_RD_BITS_PER_WORD        _IOR(SPI_IOC_MAGIC, 3, __u8)
+#define SPI_IOC_WR_BITS_PER_WORD        _IOW(SPI_IOC_MAGIC, 3, __u8)
+
+/* Read / Write SPI device default max speed hz */
+#define SPI_IOC_RD_MAX_SPEED_HZ         _IOR(SPI_IOC_MAGIC, 4, __u32)
+#define SPI_IOC_WR_MAX_SPEED_HZ         _IOW(SPI_IOC_MAGIC, 4, __u32)
+
+
+
+#endif /* SPIDEV_H */