813c1b27fe
stop, read, and write methods. Some controllers don't implement these individual operations and have only a transfer method. In that case, we should return an indication that the device is present but doesn't support the method, as opposed to the kobj default error ENXIO which makes it look like the whole device is missing. Userland tools such as i2c(8) can use the differing return values to switch between the two different i2c IO mechanisms.
148 lines
3.1 KiB
Objective-C
148 lines
3.1 KiB
Objective-C
#-
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# Copyright (c) 1998 Nicolas Souchu
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions
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# are met:
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# 1. Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# 2. Redistributions in binary form must reproduce the above copyright
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# notice, this list of conditions and the following disclaimer in the
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# documentation and/or other materials provided with the distribution.
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#
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# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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# SUCH DAMAGE.
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#
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# $FreeBSD$
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#
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#include <sys/bus.h>
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#include <dev/iicbus/iic.h>
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INTERFACE iicbus;
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CODE {
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static int iicbus_nosupport(void)
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{
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return (ENODEV);
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}
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static u_int
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iicbus_default_frequency(device_t bus, u_char speed)
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{
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return (100000);
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}
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};
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#
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# Interpret interrupt
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#
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METHOD int intr {
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device_t dev;
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int event;
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char *buf;
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};
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#
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# iicbus callback
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# Request ownership of bus
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# index: IIC_REQUEST_BUS or IIC_RELEASE_BUS
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# data: pointer to int containing IIC_WAIT or IIC_DONTWAIT and either IIC_INTR or IIC_NOINTR
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# This function is allowed to sleep if *data contains IIC_WAIT.
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#
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METHOD int callback {
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device_t dev;
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int index;
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caddr_t data;
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};
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#
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# Send REPEATED_START condition
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#
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METHOD int repeated_start {
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device_t dev;
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u_char slave;
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int timeout;
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} DEFAULT iicbus_nosupport;
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#
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# Send START condition
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#
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METHOD int start {
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device_t dev;
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u_char slave;
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int timeout;
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} DEFAULT iicbus_nosupport;
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#
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# Send STOP condition
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#
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METHOD int stop {
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device_t dev;
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} DEFAULT iicbus_nosupport;
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#
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# Read from I2C bus
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#
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METHOD int read {
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device_t dev;
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char *buf;
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int len;
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int *bytes;
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int last;
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int delay;
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} DEFAULT iicbus_nosupport;
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#
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# Write to the I2C bus
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#
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METHOD int write {
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device_t dev;
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const char *buf;
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int len;
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int *bytes;
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int timeout;
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} DEFAULT iicbus_nosupport;
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#
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# Reset I2C bus
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#
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METHOD int reset {
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device_t dev;
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u_char speed;
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u_char addr;
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u_char *oldaddr;
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};
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#
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# Generalized Read/Write interface
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#
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METHOD int transfer {
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device_t dev;
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struct iic_msg *msgs;
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uint32_t nmsgs;
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};
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#
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# Return the frequency in Hz for the bus running at the given
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# symbolic speed. Only the IIC_SLOW speed has meaning, it is always
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# 100KHz. The UNKNOWN, FAST, and FASTEST rates all map to the
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# configured bus frequency, or 100KHz when not otherwise configured.
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#
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METHOD u_int get_frequency {
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device_t dev;
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u_char speed;
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} DEFAULT iicbus_default_frequency;
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