add 1-wire support
export for each device via param the familly id (fid) the id the full reg_num so for simple 64bit memory rom(ds2401/ds2411/ds1990*) no need driver. Based on linux implementation, cleaned and re-implement the master/slave support to use the device/driver model correctly. Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Jean-Christophe PLAGNIOL-VILLARD
Sascha Hauer
parent
cf1670486b
commit
6b21594df0
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@ -21,5 +21,6 @@ source "drivers/pwm/Kconfig"
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source "drivers/dma/Kconfig"
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source "drivers/gpio/Kconfig"
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source "drivers/of/Kconfig"
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source "drivers/w1/Kconfig"
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endmenu
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@ -21,3 +21,4 @@ obj-y += dma/
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obj-y += watchdog/
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obj-y += gpio/
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obj-$(CONFIG_OFDEVICE) += of/
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obj-$(CONFIG_W1) += w1/
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@ -0,0 +1,14 @@
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menuconfig W1
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bool "Dallas's 1-wire support"
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---help---
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Dallas' 1-wire bus is useful to connect slow 1-pin devices
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such as iButtons and thermal sensors.
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If you want W1 support, you should say Y here.
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if W1
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source drivers/w1/masters/Kconfig
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source drivers/w1/slaves/Kconfig
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endif # W1
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@ -0,0 +1,6 @@
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#
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# Makefile for the Dallas's 1-wire bus.
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#
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obj-$(CONFIG_W1) += w1.o
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obj-y += masters/ slaves/
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@ -0,0 +1,7 @@
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#
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# 1-wire bus master configuration
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#
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menu "1-wire Bus Masters"
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endmenu
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@ -0,0 +1,4 @@
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#
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# Makefile for 1-wire bus master drivers.
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#
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@ -0,0 +1,7 @@
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#
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# 1-wire slaves configuration
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#
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menu "1-wire Slaves"
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endmenu
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@ -0,0 +1,4 @@
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#
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# Makefile for the Dallas's 1-wire slaves.
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#
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@ -0,0 +1,621 @@
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/*
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* Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
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* Copyright (c) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <common.h>
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#include <init.h>
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#include <clock.h>
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#include "w1.h"
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static LIST_HEAD(w1_buses);
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static void w1_pre_write(struct w1_bus *bus);
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static void w1_post_write(struct w1_bus *bus);
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static void w1_delay(unsigned long usecs)
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{
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uint64_t start = get_time_ns();
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while(!is_timeout_non_interruptible(start, usecs * USECOND));
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}
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static u8 w1_crc8_table[] = {
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0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
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157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
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35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
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190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
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70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
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219, 133, 103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
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101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
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248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
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140, 210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113, 147, 205,
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17, 79, 173, 243, 112, 46, 204, 146, 211, 141, 111, 49, 178, 236, 14, 80,
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175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82, 176, 238,
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50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
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202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
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87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
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233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168,
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116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53
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};
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u8 w1_calc_crc8(u8 * data, int len)
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{
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u8 crc = 0;
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while (len--)
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crc = w1_crc8_table[crc ^ *data++];
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return crc;
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}
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/**
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* Issues a reset bus sequence.
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*
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* @param dev The bus master pointer
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* @return 0=Device present, 1=No device present or error
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*/
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int w1_reset_bus(struct w1_bus *bus)
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{
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return bus->reset_bus(bus) & 0x1;
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}
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static u8 w1_soft_reset_bus(struct w1_bus *bus)
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{
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int result;
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bus->write_bit(bus, 0);
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/* minimum 480, max ? us
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* be nice and sleep, except 18b20 spec lists 960us maximum,
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* so until we can sleep with microsecond accuracy, spin.
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* Feel free to come up with some other way to give up the
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* cpu for such a short amount of time AND get it back in
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* the maximum amount of time.
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*/
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w1_delay(500);
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bus->write_bit(bus, 1);
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w1_delay(70);
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result = bus->read_bit(bus) & 0x1;
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/* minmum 70 (above) + 430 = 500 us
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* There aren't any timing requirements between a reset and
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* the following transactions. Sleeping is safe here.
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*/
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/* w1_delay(430); min required time */
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mdelay(1);
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return result;
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}
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/**
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* Generates a write-0 or write-1 cycle and samples the level.
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*/
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static u8 w1_touch_bit(struct w1_bus *bus, int bit)
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{
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return bus->touch_bit(bus, bit);
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}
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/**
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* Generates a write-0 or write-1 cycle.
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* Only call if dev->bus_master->touch_bit is NULL
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*/
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static void w1_write_bit(struct w1_bus *bus, int bit)
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{
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if (bit) {
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bus->write_bit(bus, 0);
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w1_delay(6);
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bus->write_bit(bus, 1);
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w1_delay(64);
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} else {
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bus->write_bit(bus, 0);
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w1_delay(60);
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bus->write_bit(bus, 1);
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w1_delay(10);
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}
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}
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/**
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* Reads 8 bits.
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*
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* @param dev the master device
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* @return the byte read
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*/
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u8 w1_read_8(struct w1_bus *bus)
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{
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return bus->read_byte(bus);
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}
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static u8 w1_soft_read_8(struct w1_bus *bus)
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{
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int i;
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u8 res = 0;
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for (i = 0; i < 8; ++i)
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res |= (w1_touch_bit(bus, 1) << i);
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return res;
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}
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/**
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* Writes a series of bytes.
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*
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* @param dev the master device
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* @param buf pointer to the data to write
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* @param len the number of bytes to write
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*/
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void w1_write_block(struct w1_bus *bus, const u8 *buf, int len)
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{
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int i;
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if (bus->write_block) {
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w1_pre_write(bus);
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bus->write_block(bus, buf, len);
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} else {
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for (i = 0; i < len; ++i)
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w1_write_8(bus, buf[i]); /* calls w1_pre_write */
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}
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w1_post_write(bus);
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}
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/**
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* Touches a series of bytes.
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*
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* @param dev the master device
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* @param buf pointer to the data to write
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* @param len the number of bytes to write
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*/
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void w1_touch_block(struct w1_bus *bus, u8 *buf, int len)
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{
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int i, j;
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u8 tmp;
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for (i = 0; i < len; ++i) {
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tmp = 0;
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for (j = 0; j < 8; ++j) {
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if (j == 7)
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w1_pre_write(bus);
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tmp |= w1_touch_bit(bus, (buf[i] >> j) & 0x1) << j;
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}
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buf[i] = tmp;
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}
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}
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/**
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* Generates a write-1 cycle and samples the level.
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* Only call if dev->bus_master->touch_bit is NULL
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*/
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static u8 w1_read_bit(struct w1_bus *bus)
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{
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int result;
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/* sample timing is critical here */
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bus->write_bit(bus, 0);
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w1_delay(6);
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bus->write_bit(bus, 1);
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w1_delay(9);
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result = bus->read_bit(bus);
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w1_delay(55);
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return result & 0x1;
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}
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/**
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* Does a triplet - used for searching ROM addresses.
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* Return bits:
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* bit 0 = id_bit
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* bit 1 = comp_bit
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* bit 2 = dir_taken
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* If both bits 0 & 1 are set, the search should be restarted.
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*
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* @param dev the master device
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* @param bdir the bit to write if both id_bit and comp_bit are 0
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* @return bit fields - see above
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*/
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u8 w1_triplet(struct w1_bus *bus, int bdir)
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{
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return bus->triplet(bus, bdir);
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}
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static u8 w1_soft_triplet(struct w1_bus *bus, u8 bdir)
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{
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u8 id_bit = w1_touch_bit(bus, 1);
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u8 comp_bit = w1_touch_bit(bus, 1);
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u8 retval;
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if (id_bit && comp_bit)
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return 0x03; /* error */
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if (!id_bit && !comp_bit) {
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/* Both bits are valid, take the direction given */
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retval = bdir ? 0x04 : 0;
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} else {
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/* Only one bit is valid, take that direction */
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bdir = id_bit;
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retval = id_bit ? 0x05 : 0x02;
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}
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w1_touch_bit(bus, bdir);
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return retval;
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}
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static u8 w1_soft_touch_bit(struct w1_bus *bus, u8 bit)
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{
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if (bit)
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return w1_read_bit(bus);
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w1_write_bit(bus, 0);
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return 0;
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}
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/**
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* Pre-write operation, currently only supporting strong pullups.
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* Program the hardware for a strong pullup, if one has been requested and
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* the hardware supports it.
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*
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* @param dev the master device
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*/
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static void w1_pre_write(struct w1_bus *bus)
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{
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if (!bus->set_pullup)
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return;
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if (bus->pullup_duration && bus->enable_pullup)
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bus->set_pullup(bus, bus->pullup_duration);
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}
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/**
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* Post-write operation, currently only supporting strong pullups.
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* If a strong pullup was requested, clear it if the hardware supports
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* them, or execute the delay otherwise, in either case clear the request.
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*
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* @param dev the master device
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*/
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static void w1_post_write(struct w1_bus *bus)
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{
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if (!bus->pullup_duration)
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return;
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if (bus->enable_pullup && bus->set_pullup)
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bus->set_pullup(bus, 0);
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else
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mdelay(bus->pullup_duration);
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bus->pullup_duration = 0;
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}
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/**
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* Writes 8 bits.
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*
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* @param dev the master device
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* @param byte the byte to write
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*/
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void w1_write_8(struct w1_bus *bus, u8 byte)
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{
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if (bus->write_byte) {
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w1_pre_write(bus);
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bus->write_byte(bus, byte);
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} else {
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int i;
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for (i = 0; i < 8; ++i) {
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if (i == 7)
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w1_pre_write(bus);
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w1_touch_bit(bus, (byte >> i) & 0x1);
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}
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}
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w1_post_write(bus);
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}
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/**
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* Reads a series of bytes.
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*
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* @param dev the master device
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* @param buf pointer to the buffer to fill
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* @param len the number of bytes to read
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* @return the number of bytes read
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*/
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u8 w1_read_block(struct w1_bus *bus, u8 *buf, int len)
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{
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return bus->read_block(bus, buf, len);
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}
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static u8 w1_soft_read_block(struct w1_bus *bus, u8 *buf, int len)
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{
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int i;
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for (i = 0; i < len; ++i)
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buf[i] = w1_read_8(bus);
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return len;
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}
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/**
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* Resets the bus and then selects the slave by sending either a skip rom
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* or a rom match.
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* The w1 master lock must be held.
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*
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* @param sl the slave to select
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* @return 0=success, anything else=error
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*/
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int w1_reset_select_slave(struct w1_device *dev)
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{
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struct w1_bus *bus = dev->bus;
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if (w1_reset_bus(bus))
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return -1;
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if (bus->slave_count == 1)
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w1_write_8(bus, W1_SKIP_ROM);
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else {
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u8 match[9] = {W1_MATCH_ROM, };
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u64 rn = le64_to_cpu(*((u64*)&dev->reg_num));
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memcpy(&match[1], &rn, 8);
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w1_write_block(bus, match, 9);
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}
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return 0;
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}
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#define to_w1_device(d) container_of(d, struct w1_device, dev)
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#define to_w1_driver(d) container_of(d, struct w1_driver, drv)
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static int w1_bus_match(struct device_d *_dev, struct driver_d *_drv)
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{
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struct w1_device *dev = to_w1_device(_dev);
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struct w1_driver *drv = to_w1_driver(_drv);
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return !(drv->fid == dev->fid);
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}
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static int w1_bus_probe(struct device_d *_dev)
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{
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struct w1_driver *drv = to_w1_driver(_dev->driver);
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struct w1_device *dev = to_w1_device(_dev);
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return drv->probe(dev);
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}
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static void w1_bus_remove(struct device_d *_dev)
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{
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struct w1_driver *drv = to_w1_driver(_dev->driver);
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struct w1_device *dev = to_w1_device(_dev);
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return drv->remove(dev);
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}
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struct bus_type w1_bustype= {
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.name = "w1_bus",
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.match = w1_bus_match,
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.probe = w1_bus_probe,
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.remove = w1_bus_remove,
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};
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static int w1_device_register(struct w1_bus *bus, struct w1_device *dev)
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{
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char str[18];
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int ret;
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sprintf(dev->dev.name, "w1-%x-", dev->fid);
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dev->dev.id = DEVICE_ID_DYNAMIC;
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dev->dev.bus = &w1_bustype;
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dev->bus = bus;
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dev->dev.parent = &bus->dev;
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dev_add_child(dev->dev.parent, &dev->dev);
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ret = register_device(&dev->dev);
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if (ret)
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return ret;
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||||
sprintf(str, "0x%x", dev->fid);
|
||||
dev_add_param_fixed(&dev->dev, "fid", str);
|
||||
sprintf(str, "0x%llx", dev->id);
|
||||
dev_add_param_fixed(&dev->dev, "id", str);
|
||||
sprintf(str, "0x%llx", dev->reg_num);
|
||||
dev_add_param_fixed(&dev->dev, "reg_num", str);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
int w1_driver_register(struct w1_driver *drv)
|
||||
{
|
||||
drv->drv.bus = &w1_bustype;
|
||||
|
||||
if (drv->probe)
|
||||
drv->drv.probe = w1_bus_probe;
|
||||
if (drv->remove)
|
||||
drv->drv.remove = w1_bus_remove;
|
||||
|
||||
return register_driver(&drv->drv);
|
||||
}
|
||||
|
||||
void w1_found(struct w1_bus *bus, u64 rn)
|
||||
{
|
||||
struct w1_device *dev = xzalloc(sizeof(*dev));
|
||||
u64 tmp = be64_to_cpu(rn);
|
||||
|
||||
dev->reg_num = rn;
|
||||
dev->fid = tmp >> 56;
|
||||
dev->id = (tmp >> 8) & 0xffffffffffff;
|
||||
dev->crc = tmp & 0xff;
|
||||
|
||||
dev_dbg(&bus->dev, "%s: familly = 0x%x, id = 0x%llx, crc = 0x%x\n",
|
||||
__func__, dev->fid, dev->id, dev->crc);
|
||||
|
||||
if (dev->crc != w1_calc_crc8((u8 *)&rn, 7)) {
|
||||
dev_err(&bus->dev, "0x%llx crc error\n", rn);
|
||||
return;
|
||||
}
|
||||
|
||||
w1_device_register(bus, dev);
|
||||
}
|
||||
|
||||
/**
|
||||
* Performs a ROM Search & registers any devices found.
|
||||
* The 1-wire search is a simple binary tree search.
|
||||
* For each bit of the address, we read two bits and write one bit.
|
||||
* The bit written will put to sleep all devies that don't match that bit.
|
||||
* When the two reads differ, the direction choice is obvious.
|
||||
* When both bits are 0, we must choose a path to take.
|
||||
* When we can scan all 64 bits without having to choose a path, we are done.
|
||||
*
|
||||
* See "Application note 187 1-wire search algorithm" at www.maxim-ic.com
|
||||
*
|
||||
* @dev The master device to search
|
||||
* @cb Function to call when a device is found
|
||||
*/
|
||||
static void w1_search(struct w1_bus *bus, u8 search_type)
|
||||
{
|
||||
u64 last_rn, rn, tmp64;
|
||||
int i, slave_count = 0;
|
||||
int last_zero, last_device;
|
||||
int search_bit, desc_bit;
|
||||
u8 triplet_ret = 0;
|
||||
|
||||
search_bit = 0;
|
||||
rn = last_rn = 0;
|
||||
last_device = 0;
|
||||
last_zero = -1;
|
||||
|
||||
desc_bit = 64;
|
||||
|
||||
while ( !last_device && (slave_count++ < bus->max_slave_count) ) {
|
||||
last_rn = rn;
|
||||
rn = 0;
|
||||
|
||||
/*
|
||||
* Reset bus and all 1-wire device state machines
|
||||
* so they can respond to our requests.
|
||||
*
|
||||
* Return 0 - device(s) present, 1 - no devices present.
|
||||
*/
|
||||
if (w1_reset_bus(bus)) {
|
||||
dev_dbg(&bus->dev, "No devices present on the wire.\n");
|
||||
break;
|
||||
}
|
||||
|
||||
/* Do fast search on single slave bus */
|
||||
if (bus->max_slave_count == 1) {
|
||||
int rv;
|
||||
w1_write_8(bus, W1_READ_ROM);
|
||||
rv = w1_read_block(bus, (u8 *)&rn, 8);
|
||||
|
||||
if (rv == 8 && rn)
|
||||
w1_found(bus, rn);
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
/* Start the search */
|
||||
w1_write_8(bus, search_type);
|
||||
for (i = 0; i < 64; ++i) {
|
||||
/* Determine the direction/search bit */
|
||||
if (i == desc_bit)
|
||||
search_bit = 1; /* took the 0 path last time, so take the 1 path */
|
||||
else if (i > desc_bit)
|
||||
search_bit = 0; /* take the 0 path on the next branch */
|
||||
else
|
||||
search_bit = ((last_rn >> i) & 0x1);
|
||||
|
||||
/** Read two bits and write one bit */
|
||||
triplet_ret = w1_triplet(bus, search_bit);
|
||||
|
||||
/* quit if no device responded */
|
||||
if ( (triplet_ret & 0x03) == 0x03 )
|
||||
break;
|
||||
|
||||
/* If both directions were valid, and we took the 0 path... */
|
||||
if (triplet_ret == 0)
|
||||
last_zero = i;
|
||||
|
||||
/* extract the direction taken & update the device number */
|
||||
tmp64 = (triplet_ret >> 2);
|
||||
rn |= (tmp64 << i);
|
||||
}
|
||||
|
||||
if ( (triplet_ret & 0x03) != 0x03 ) {
|
||||
if ( (desc_bit == last_zero) || (last_zero < 0))
|
||||
last_device = 1;
|
||||
desc_bit = last_zero;
|
||||
w1_found(bus, rn);
|
||||
}
|
||||
}
|
||||
|
||||
w1_reset_bus(bus);
|
||||
}
|
||||
|
||||
int w1_bus_register(struct w1_bus *bus)
|
||||
{
|
||||
int ret;
|
||||
|
||||
/* validate minimum functionality */
|
||||
if (!(bus->touch_bit && bus->reset_bus) &&
|
||||
!(bus->write_bit && bus->read_bit)) {
|
||||
pr_err("w1_bus_register: invalid function set\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
/* While it would be electrically possible to make a device that
|
||||
* generated a strong pullup in bit bang mode, only hardware that
|
||||
* controls 1-wire time frames are even expected to support a strong
|
||||
* pullup. w1_io.c would need to support calling set_pullup before
|
||||
* the last write_bit operation of a w1_write_8 which it currently
|
||||
* doesn't.
|
||||
*/
|
||||
if (!bus->touch_bit && bus->set_pullup) {
|
||||
pr_err("w1_add_bus_device: set_pullup requires touch_bit, disabling\n");
|
||||
bus->set_pullup = NULL;
|
||||
}
|
||||
|
||||
if (!bus->reset_bus)
|
||||
bus->reset_bus = w1_soft_reset_bus;
|
||||
|
||||
if (!bus->touch_bit)
|
||||
bus->touch_bit = w1_soft_touch_bit;
|
||||
|
||||
if (!bus->read_block)
|
||||
bus->read_block = w1_soft_read_block;
|
||||
|
||||
if (!bus->read_byte)
|
||||
bus->read_byte = w1_soft_read_8;
|
||||
|
||||
if (!bus->triplet)
|
||||
bus->triplet = w1_soft_triplet;
|
||||
|
||||
if (!bus->max_slave_count)
|
||||
bus->max_slave_count = 10;
|
||||
|
||||
list_add_tail(&bus->list, &w1_buses);
|
||||
|
||||
strcpy(bus->dev.name, "w1_bus");
|
||||
bus->dev.id = DEVICE_ID_DYNAMIC;
|
||||
|
||||
bus->dev.parent = bus->parent;
|
||||
if (bus->parent)
|
||||
dev_add_child(bus->parent, &bus->dev);
|
||||
|
||||
ret = register_device(&bus->dev);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
w1_search(bus, W1_SEARCH);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int w1_bus_init(void)
|
||||
{
|
||||
return bus_register(&w1_bustype);
|
||||
}
|
||||
pure_initcall(w1_bus_init);
|
||||
|
|
@ -0,0 +1,152 @@
|
|||
/*
|
||||
* w1.h
|
||||
*
|
||||
* Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
|
||||
* Copyright (c) 2012 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
|
||||
*
|
||||
* 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.
|
||||
*/
|
||||
|
||||
#ifndef __W1_H
|
||||
#define __W1_H
|
||||
|
||||
#include <common.h>
|
||||
#include <driver.h>
|
||||
|
||||
struct w1_device {
|
||||
u64 reg_num;
|
||||
u8 fid;
|
||||
u64 id;
|
||||
u8 crc;
|
||||
|
||||
struct w1_bus *bus;
|
||||
struct device_d dev;
|
||||
};
|
||||
|
||||
struct w1_driver {
|
||||
u8 fid;
|
||||
u64 id;
|
||||
|
||||
int (*probe) (struct w1_device *dev);
|
||||
void (*remove) (struct w1_device *dev);
|
||||
struct driver_d drv;
|
||||
};
|
||||
|
||||
int w1_driver_register(struct w1_driver *drv);
|
||||
|
||||
extern struct bus_type w1_bustype;
|
||||
|
||||
#define W1_MAXNAMELEN 32
|
||||
|
||||
#define W1_SEARCH 0xF0
|
||||
#define W1_ALARM_SEARCH 0xEC
|
||||
#define W1_CONVERT_TEMP 0x44
|
||||
#define W1_SKIP_ROM 0xCC
|
||||
#define W1_READ_SCRATCHPAD 0xBE
|
||||
#define W1_READ_ROM 0x33
|
||||
#define W1_READ_PSUPPLY 0xB4
|
||||
#define W1_MATCH_ROM 0x55
|
||||
#define W1_RESUME_CMD 0xA5
|
||||
|
||||
#define W1_SLAVE_ACTIVE 0
|
||||
|
||||
/**
|
||||
* Note: read_bit and write_bit are very low level functions and should only
|
||||
* be used with hardware that doesn't really support 1-wire operations,
|
||||
* like a parallel/serial port.
|
||||
* Either define read_bit and write_bit OR define, at minimum, touch_bit and
|
||||
* reset_bus.
|
||||
*/
|
||||
struct w1_bus
|
||||
{
|
||||
struct device_d dev;
|
||||
struct device_d *parent;
|
||||
|
||||
/**
|
||||
* Sample the line level
|
||||
* @return the level read (0 or 1)
|
||||
*/
|
||||
u8 (*read_bit)(struct w1_bus *);
|
||||
|
||||
/** Sets the line level */
|
||||
void (*write_bit)(struct w1_bus *, u8);
|
||||
|
||||
/**
|
||||
* touch_bit is the lowest-level function for devices that really
|
||||
* support the 1-wire protocol.
|
||||
* touch_bit(0) = write-0 cycle
|
||||
* touch_bit(1) = write-1 / read cycle
|
||||
* @return the bit read (0 or 1)
|
||||
*/
|
||||
u8 (*touch_bit)(struct w1_bus *, u8);
|
||||
|
||||
/**
|
||||
* Reads a bytes. Same as 8 touch_bit(1) calls.
|
||||
* @return the byte read
|
||||
*/
|
||||
u8 (*read_byte)(struct w1_bus *);
|
||||
|
||||
/**
|
||||
* Writes a byte. Same as 8 touch_bit(x) calls.
|
||||
*/
|
||||
void (*write_byte)(struct w1_bus *, u8);
|
||||
|
||||
/**
|
||||
* Same as a series of read_byte() calls
|
||||
* @return the number of bytes read
|
||||
*/
|
||||
u8 (*read_block)(struct w1_bus *, u8 *, int);
|
||||
|
||||
/** Same as a series of write_byte() calls */
|
||||
void (*write_block)(struct w1_bus *, const u8 *, int);
|
||||
|
||||
/**
|
||||
* Combines two reads and a smart write for ROM searches
|
||||
* @return bit0=Id bit1=comp_id bit2=dir_taken
|
||||
*/
|
||||
u8 (*triplet)(struct w1_bus *, u8);
|
||||
|
||||
/**
|
||||
* long write-0 with a read for the presence pulse detection
|
||||
* @return -1=Error, 0=Device present, 1=No device present
|
||||
*/
|
||||
u8 (*reset_bus)(struct w1_bus *);
|
||||
|
||||
/**
|
||||
* Put out a strong pull-up pulse of the specified duration.
|
||||
* @return -1=Error, 0=completed
|
||||
*/
|
||||
u8 (*set_pullup)(struct w1_bus *, int);
|
||||
|
||||
/** 5V strong pullup enabled flag, 1 enabled, zero disabled. */
|
||||
int enable_pullup;
|
||||
/** 5V strong pullup duration in milliseconds, zero disabled. */
|
||||
int pullup_duration;
|
||||
|
||||
int max_slave_count, slave_count;
|
||||
|
||||
void *data;
|
||||
struct list_head list;
|
||||
};
|
||||
|
||||
u8 w1_read_block(struct w1_bus *bus, u8 *buf, int len);
|
||||
void w1_write_block(struct w1_bus *bus, const u8 *buf, int len);
|
||||
void w1_touch_block(struct w1_bus *bus, u8 *buf, int len);
|
||||
u8 w1_triplet(struct w1_bus *bus, int bdir);
|
||||
u8 w1_read_8(struct w1_bus *bus);
|
||||
void w1_write_8(struct w1_bus *bus, u8 byte);
|
||||
int w1_reset_select_slave(struct w1_device *dev);
|
||||
int w1_reset_bus(struct w1_bus *bus);
|
||||
u8 w1_calc_crc8(u8 * data, int len);
|
||||
|
||||
int w1_bus_register(struct w1_bus *bus);
|
||||
|
||||
#endif /* __W1_H */
|
||||
Loading…
Reference in New Issue