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b24413180f
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
700 lines
14 KiB
C
700 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*!***************************************************************************
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*!
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*! FILE NAME : i2c.c
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*!
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*! DESCRIPTION: implements an interface for IIC/I2C, both directly from other
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*! kernel modules (i2c_writereg/readreg) and from userspace using
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*! ioctl()'s
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*!
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*! (C) Copyright 1999-2007 Axis Communications AB, LUND, SWEDEN
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*!
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*!***************************************************************************/
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/****************** INCLUDE FILES SECTION ***********************************/
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/fs.h>
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#include <linux/string.h>
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#include <linux/init.h>
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#include <asm/etraxi2c.h>
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#include <arch/svinto.h>
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#include <asm/io.h>
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#include <asm/delay.h>
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#include <arch/io_interface_mux.h>
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#include "i2c.h"
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/****************** I2C DEFINITION SECTION *************************/
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#define D(x)
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#define I2C_MAJOR 123 /* LOCAL/EXPERIMENTAL */
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static const char i2c_name[] = "i2c";
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#define CLOCK_LOW_TIME 8
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#define CLOCK_HIGH_TIME 8
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#define START_CONDITION_HOLD_TIME 8
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#define STOP_CONDITION_HOLD_TIME 8
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#define ENABLE_OUTPUT 0x01
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#define ENABLE_INPUT 0x00
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#define I2C_CLOCK_HIGH 1
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#define I2C_CLOCK_LOW 0
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#define I2C_DATA_HIGH 1
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#define I2C_DATA_LOW 0
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#ifdef CONFIG_ETRAX_I2C_USES_PB_NOT_PB_I2C
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/* Use PB and not PB_I2C */
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#ifndef CONFIG_ETRAX_I2C_DATA_PORT
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#define CONFIG_ETRAX_I2C_DATA_PORT 0
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#endif
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#ifndef CONFIG_ETRAX_I2C_CLK_PORT
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#define CONFIG_ETRAX_I2C_CLK_PORT 1
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#endif
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#define SDABIT CONFIG_ETRAX_I2C_DATA_PORT
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#define SCLBIT CONFIG_ETRAX_I2C_CLK_PORT
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#define i2c_enable()
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#define i2c_disable()
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/* enable or disable output-enable, to select output or input on the i2c bus */
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#define i2c_dir_out() \
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REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, SDABIT, 1)
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#define i2c_dir_in() \
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REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, SDABIT, 0)
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/* control the i2c clock and data signals */
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#define i2c_clk(x) \
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REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, SCLBIT, x)
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#define i2c_data(x) \
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REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, SDABIT, x)
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/* read a bit from the i2c interface */
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#define i2c_getbit() (((*R_PORT_PB_READ & (1 << SDABIT))) >> SDABIT)
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#else
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/* enable or disable the i2c interface */
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#define i2c_enable() *R_PORT_PB_I2C = (port_pb_i2c_shadow |= IO_MASK(R_PORT_PB_I2C, i2c_en))
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#define i2c_disable() *R_PORT_PB_I2C = (port_pb_i2c_shadow &= ~IO_MASK(R_PORT_PB_I2C, i2c_en))
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/* enable or disable output-enable, to select output or input on the i2c bus */
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#define i2c_dir_out() \
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*R_PORT_PB_I2C = (port_pb_i2c_shadow &= ~IO_MASK(R_PORT_PB_I2C, i2c_oe_)); \
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REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, 0, 1);
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#define i2c_dir_in() \
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*R_PORT_PB_I2C = (port_pb_i2c_shadow |= IO_MASK(R_PORT_PB_I2C, i2c_oe_)); \
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REG_SHADOW_SET(R_PORT_PB_DIR, port_pb_dir_shadow, 0, 0);
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/* control the i2c clock and data signals */
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#define i2c_clk(x) \
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*R_PORT_PB_I2C = (port_pb_i2c_shadow = (port_pb_i2c_shadow & \
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~IO_MASK(R_PORT_PB_I2C, i2c_clk)) | IO_FIELD(R_PORT_PB_I2C, i2c_clk, (x))); \
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REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, 1, x);
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#define i2c_data(x) \
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*R_PORT_PB_I2C = (port_pb_i2c_shadow = (port_pb_i2c_shadow & \
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~IO_MASK(R_PORT_PB_I2C, i2c_d)) | IO_FIELD(R_PORT_PB_I2C, i2c_d, (x))); \
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REG_SHADOW_SET(R_PORT_PB_DATA, port_pb_data_shadow, 0, x);
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/* read a bit from the i2c interface */
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#define i2c_getbit() (*R_PORT_PB_READ & 0x1)
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#endif
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/* use the kernels delay routine */
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#define i2c_delay(usecs) udelay(usecs)
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static DEFINE_SPINLOCK(i2c_lock); /* Protect directions etc */
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/****************** FUNCTION DEFINITION SECTION *************************/
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/* generate i2c start condition */
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void
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i2c_start(void)
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{
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/*
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* SCL=1 SDA=1
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*/
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i2c_dir_out();
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i2c_delay(CLOCK_HIGH_TIME/6);
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i2c_data(I2C_DATA_HIGH);
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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/*
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* SCL=1 SDA=0
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*/
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i2c_data(I2C_DATA_LOW);
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i2c_delay(START_CONDITION_HOLD_TIME);
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/*
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* SCL=0 SDA=0
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*/
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_LOW_TIME);
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}
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/* generate i2c stop condition */
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void
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i2c_stop(void)
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{
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i2c_dir_out();
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/*
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* SCL=0 SDA=0
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*/
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i2c_clk(I2C_CLOCK_LOW);
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i2c_data(I2C_DATA_LOW);
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i2c_delay(CLOCK_LOW_TIME*2);
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/*
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* SCL=1 SDA=0
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*/
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME*2);
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/*
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* SCL=1 SDA=1
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*/
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i2c_data(I2C_DATA_HIGH);
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i2c_delay(STOP_CONDITION_HOLD_TIME);
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i2c_dir_in();
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}
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/* write a byte to the i2c interface */
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void
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i2c_outbyte(unsigned char x)
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{
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int i;
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i2c_dir_out();
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for (i = 0; i < 8; i++) {
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if (x & 0x80) {
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i2c_data(I2C_DATA_HIGH);
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} else {
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i2c_data(I2C_DATA_LOW);
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}
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i2c_delay(CLOCK_LOW_TIME/2);
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_LOW_TIME/2);
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x <<= 1;
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}
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i2c_data(I2C_DATA_LOW);
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i2c_delay(CLOCK_LOW_TIME/2);
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/*
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* enable input
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*/
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i2c_dir_in();
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}
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/* read a byte from the i2c interface */
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unsigned char
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i2c_inbyte(void)
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{
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unsigned char aBitByte = 0;
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int i;
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/* Switch off I2C to get bit */
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i2c_disable();
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i2c_dir_in();
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i2c_delay(CLOCK_HIGH_TIME/2);
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/* Get bit */
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aBitByte |= i2c_getbit();
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/* Enable I2C */
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i2c_enable();
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i2c_delay(CLOCK_LOW_TIME/2);
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for (i = 1; i < 8; i++) {
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aBitByte <<= 1;
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/* Clock pulse */
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_LOW_TIME);
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/* Switch off I2C to get bit */
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i2c_disable();
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i2c_dir_in();
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i2c_delay(CLOCK_HIGH_TIME/2);
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/* Get bit */
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aBitByte |= i2c_getbit();
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/* Enable I2C */
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i2c_enable();
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i2c_delay(CLOCK_LOW_TIME/2);
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}
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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/*
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* we leave the clock low, getbyte is usually followed
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* by sendack/nack, they assume the clock to be low
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*/
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i2c_clk(I2C_CLOCK_LOW);
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return aBitByte;
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}
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/*#---------------------------------------------------------------------------
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*#
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*# FUNCTION NAME: i2c_getack
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*#
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*# DESCRIPTION : checks if ack was received from ic2
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*#
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*#--------------------------------------------------------------------------*/
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int
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i2c_getack(void)
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{
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int ack = 1;
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/*
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* enable output
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*/
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i2c_dir_out();
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/*
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* Release data bus by setting
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* data high
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*/
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i2c_data(I2C_DATA_HIGH);
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/*
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* enable input
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*/
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i2c_dir_in();
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i2c_delay(CLOCK_HIGH_TIME/4);
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/*
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* generate ACK clock pulse
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*/
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i2c_clk(I2C_CLOCK_HIGH);
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/*
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* Use PORT PB instead of I2C
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* for input. (I2C not working)
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*/
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i2c_clk(1);
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i2c_data(1);
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/*
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* switch off I2C
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*/
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i2c_data(1);
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i2c_disable();
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i2c_dir_in();
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/*
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* now wait for ack
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*/
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i2c_delay(CLOCK_HIGH_TIME/2);
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/*
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* check for ack
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*/
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if(i2c_getbit())
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ack = 0;
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i2c_delay(CLOCK_HIGH_TIME/2);
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if(!ack){
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if(!i2c_getbit()) /* receiver pulld SDA low */
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ack = 1;
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i2c_delay(CLOCK_HIGH_TIME/2);
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}
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/*
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* our clock is high now, make sure data is low
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* before we enable our output. If we keep data high
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* and enable output, we would generate a stop condition.
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*/
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i2c_data(I2C_DATA_LOW);
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/*
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* end clock pulse
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*/
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i2c_enable();
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i2c_dir_out();
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_HIGH_TIME/4);
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/*
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* enable output
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*/
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i2c_dir_out();
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/*
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* remove ACK clock pulse
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*/
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i2c_data(I2C_DATA_HIGH);
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i2c_delay(CLOCK_LOW_TIME/2);
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return ack;
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}
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/*#---------------------------------------------------------------------------
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*#
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*# FUNCTION NAME: I2C::sendAck
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*#
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*# DESCRIPTION : Send ACK on received data
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*#
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*#--------------------------------------------------------------------------*/
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void
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i2c_sendack(void)
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{
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/*
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* enable output
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*/
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i2c_delay(CLOCK_LOW_TIME);
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i2c_dir_out();
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/*
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* set ack pulse high
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*/
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i2c_data(I2C_DATA_LOW);
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/*
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* generate clock pulse
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*/
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i2c_delay(CLOCK_HIGH_TIME/6);
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_LOW_TIME/6);
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/*
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* reset data out
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*/
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i2c_data(I2C_DATA_HIGH);
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i2c_delay(CLOCK_LOW_TIME);
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i2c_dir_in();
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}
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/*#---------------------------------------------------------------------------
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*#
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*# FUNCTION NAME: i2c_sendnack
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*#
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*# DESCRIPTION : Sends NACK on received data
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*#
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*#--------------------------------------------------------------------------*/
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void
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i2c_sendnack(void)
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{
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/*
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* enable output
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*/
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i2c_delay(CLOCK_LOW_TIME);
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i2c_dir_out();
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/*
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* set data high
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*/
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i2c_data(I2C_DATA_HIGH);
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/*
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* generate clock pulse
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*/
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i2c_delay(CLOCK_HIGH_TIME/6);
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i2c_clk(I2C_CLOCK_HIGH);
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i2c_delay(CLOCK_HIGH_TIME);
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i2c_clk(I2C_CLOCK_LOW);
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i2c_delay(CLOCK_LOW_TIME);
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i2c_dir_in();
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}
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/*#---------------------------------------------------------------------------
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*#
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*# FUNCTION NAME: i2c_writereg
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*#
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*# DESCRIPTION : Writes a value to an I2C device
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*#
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*#--------------------------------------------------------------------------*/
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int
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i2c_writereg(unsigned char theSlave, unsigned char theReg,
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unsigned char theValue)
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{
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int error, cntr = 3;
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unsigned long flags;
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spin_lock(&i2c_lock);
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do {
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error = 0;
|
|
/*
|
|
* we don't like to be interrupted
|
|
*/
|
|
local_irq_save(flags);
|
|
|
|
i2c_start();
|
|
/*
|
|
* send slave address
|
|
*/
|
|
i2c_outbyte((theSlave & 0xfe));
|
|
/*
|
|
* wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error = 1;
|
|
/*
|
|
* now select register
|
|
*/
|
|
i2c_dir_out();
|
|
i2c_outbyte(theReg);
|
|
/*
|
|
* now it's time to wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error |= 2;
|
|
/*
|
|
* send register register data
|
|
*/
|
|
i2c_outbyte(theValue);
|
|
/*
|
|
* now it's time to wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error |= 4;
|
|
/*
|
|
* end byte stream
|
|
*/
|
|
i2c_stop();
|
|
/*
|
|
* enable interrupt again
|
|
*/
|
|
local_irq_restore(flags);
|
|
|
|
} while(error && cntr--);
|
|
|
|
i2c_delay(CLOCK_LOW_TIME);
|
|
|
|
spin_unlock(&i2c_lock);
|
|
|
|
return -error;
|
|
}
|
|
|
|
/*#---------------------------------------------------------------------------
|
|
*#
|
|
*# FUNCTION NAME: i2c_readreg
|
|
*#
|
|
*# DESCRIPTION : Reads a value from the decoder registers.
|
|
*#
|
|
*#--------------------------------------------------------------------------*/
|
|
unsigned char
|
|
i2c_readreg(unsigned char theSlave, unsigned char theReg)
|
|
{
|
|
unsigned char b = 0;
|
|
int error, cntr = 3;
|
|
unsigned long flags;
|
|
|
|
spin_lock(&i2c_lock);
|
|
|
|
do {
|
|
error = 0;
|
|
/*
|
|
* we don't like to be interrupted
|
|
*/
|
|
local_irq_save(flags);
|
|
/*
|
|
* generate start condition
|
|
*/
|
|
i2c_start();
|
|
|
|
/*
|
|
* send slave address
|
|
*/
|
|
i2c_outbyte((theSlave & 0xfe));
|
|
/*
|
|
* wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error = 1;
|
|
/*
|
|
* now select register
|
|
*/
|
|
i2c_dir_out();
|
|
i2c_outbyte(theReg);
|
|
/*
|
|
* now it's time to wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error = 1;
|
|
/*
|
|
* repeat start condition
|
|
*/
|
|
i2c_delay(CLOCK_LOW_TIME);
|
|
i2c_start();
|
|
/*
|
|
* send slave address
|
|
*/
|
|
i2c_outbyte(theSlave | 0x01);
|
|
/*
|
|
* wait for ack
|
|
*/
|
|
if(!i2c_getack())
|
|
error = 1;
|
|
/*
|
|
* fetch register
|
|
*/
|
|
b = i2c_inbyte();
|
|
/*
|
|
* last received byte needs to be nacked
|
|
* instead of acked
|
|
*/
|
|
i2c_sendnack();
|
|
/*
|
|
* end sequence
|
|
*/
|
|
i2c_stop();
|
|
/*
|
|
* enable interrupt again
|
|
*/
|
|
local_irq_restore(flags);
|
|
|
|
} while(error && cntr--);
|
|
|
|
spin_unlock(&i2c_lock);
|
|
|
|
return b;
|
|
}
|
|
|
|
static int
|
|
i2c_open(struct inode *inode, struct file *filp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
i2c_release(struct inode *inode, struct file *filp)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/* Main device API. ioctl's to write or read to/from i2c registers.
|
|
*/
|
|
|
|
static long i2c_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
|
{
|
|
if(_IOC_TYPE(cmd) != ETRAXI2C_IOCTYPE) {
|
|
return -EINVAL;
|
|
}
|
|
|
|
switch (_IOC_NR(cmd)) {
|
|
case I2C_WRITEREG:
|
|
/* write to an i2c slave */
|
|
D(printk(KERN_DEBUG "i2cw %d %d %d\n",
|
|
I2C_ARGSLAVE(arg),
|
|
I2C_ARGREG(arg),
|
|
I2C_ARGVALUE(arg)));
|
|
|
|
return i2c_writereg(I2C_ARGSLAVE(arg),
|
|
I2C_ARGREG(arg),
|
|
I2C_ARGVALUE(arg));
|
|
case I2C_READREG:
|
|
{
|
|
unsigned char val;
|
|
/* read from an i2c slave */
|
|
D(printk(KERN_DEBUG "i2cr %d %d ",
|
|
I2C_ARGSLAVE(arg),
|
|
I2C_ARGREG(arg)));
|
|
val = i2c_readreg(I2C_ARGSLAVE(arg), I2C_ARGREG(arg));
|
|
D(printk(KERN_DEBUG "= %d\n", val));
|
|
return val;
|
|
}
|
|
default:
|
|
return -EINVAL;
|
|
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations i2c_fops = {
|
|
.owner = THIS_MODULE,
|
|
.unlocked_ioctl = i2c_ioctl,
|
|
.open = i2c_open,
|
|
.release = i2c_release,
|
|
.llseek = noop_llseek,
|
|
};
|
|
|
|
int __init
|
|
i2c_init(void)
|
|
{
|
|
static int res = 0;
|
|
static int first = 1;
|
|
|
|
if (!first) {
|
|
return res;
|
|
}
|
|
first = 0;
|
|
|
|
/* Setup and enable the Port B I2C interface */
|
|
|
|
#ifndef CONFIG_ETRAX_I2C_USES_PB_NOT_PB_I2C
|
|
if ((res = cris_request_io_interface(if_i2c, "I2C"))) {
|
|
printk(KERN_CRIT "i2c_init: Failed to get IO interface\n");
|
|
return res;
|
|
}
|
|
|
|
*R_PORT_PB_I2C = port_pb_i2c_shadow |=
|
|
IO_STATE(R_PORT_PB_I2C, i2c_en, on) |
|
|
IO_FIELD(R_PORT_PB_I2C, i2c_d, 1) |
|
|
IO_FIELD(R_PORT_PB_I2C, i2c_clk, 1) |
|
|
IO_STATE(R_PORT_PB_I2C, i2c_oe_, enable);
|
|
|
|
port_pb_dir_shadow &= ~IO_MASK(R_PORT_PB_DIR, dir0);
|
|
port_pb_dir_shadow &= ~IO_MASK(R_PORT_PB_DIR, dir1);
|
|
|
|
*R_PORT_PB_DIR = (port_pb_dir_shadow |=
|
|
IO_STATE(R_PORT_PB_DIR, dir0, input) |
|
|
IO_STATE(R_PORT_PB_DIR, dir1, output));
|
|
#else
|
|
if ((res = cris_io_interface_allocate_pins(if_i2c,
|
|
'b',
|
|
CONFIG_ETRAX_I2C_DATA_PORT,
|
|
CONFIG_ETRAX_I2C_DATA_PORT))) {
|
|
printk(KERN_WARNING "i2c_init: Failed to get IO pin for I2C data port\n");
|
|
return res;
|
|
} else if ((res = cris_io_interface_allocate_pins(if_i2c,
|
|
'b',
|
|
CONFIG_ETRAX_I2C_CLK_PORT,
|
|
CONFIG_ETRAX_I2C_CLK_PORT))) {
|
|
cris_io_interface_free_pins(if_i2c,
|
|
'b',
|
|
CONFIG_ETRAX_I2C_DATA_PORT,
|
|
CONFIG_ETRAX_I2C_DATA_PORT);
|
|
printk(KERN_WARNING "i2c_init: Failed to get IO pin for I2C clk port\n");
|
|
}
|
|
#endif
|
|
|
|
return res;
|
|
}
|
|
|
|
static int __init
|
|
i2c_register(void)
|
|
{
|
|
int res;
|
|
|
|
res = i2c_init();
|
|
if (res < 0)
|
|
return res;
|
|
res = register_chrdev(I2C_MAJOR, i2c_name, &i2c_fops);
|
|
if(res < 0) {
|
|
printk(KERN_ERR "i2c: couldn't get a major number.\n");
|
|
return res;
|
|
}
|
|
|
|
printk(KERN_INFO "I2C driver v2.2, (c) 1999-2004 Axis Communications AB\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* this makes sure that i2c_register is called during boot */
|
|
|
|
module_init(i2c_register);
|
|
|
|
/****************** END OF FILE i2c.c ********************************/
|