diff options
author | 2016-04-11 10:41:07 +0300 | |
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committer | 2016-04-13 08:17:18 +0300 | |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/arch/cris/arch-v32/drivers/i2c.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/arch/cris/arch-v32/drivers/i2c.c')
-rw-r--r-- | kernel/arch/cris/arch-v32/drivers/i2c.c | 751 |
1 files changed, 0 insertions, 751 deletions
diff --git a/kernel/arch/cris/arch-v32/drivers/i2c.c b/kernel/arch/cris/arch-v32/drivers/i2c.c deleted file mode 100644 index 3b2c82ce8..000000000 --- a/kernel/arch/cris/arch-v32/drivers/i2c.c +++ /dev/null @@ -1,751 +0,0 @@ -/*!*************************************************************************** -*! -*! FILE NAME : i2c.c -*! -*! DESCRIPTION: implements an interface for IIC/I2C, both directly from other -*! kernel modules (i2c_writereg/readreg) and from userspace using -*! ioctl()'s -*! -*! Nov 30 1998 Torbjorn Eliasson Initial version. -*! Bjorn Wesen Elinux kernel version. -*! Jan 14 2000 Johan Adolfsson Fixed PB shadow register stuff - -*! don't use PB_I2C if DS1302 uses same bits, -*! use PB. -*| June 23 2003 Pieter Grimmerink Added 'i2c_sendnack'. i2c_readreg now -*| generates nack on last received byte, -*| instead of ack. -*| i2c_getack changed data level while clock -*| was high, causing DS75 to see a stop condition -*! -*! --------------------------------------------------------------------------- -*! -*! (C) Copyright 1999-2007 Axis Communications AB, LUND, SWEDEN -*! -*!***************************************************************************/ - -/****************** INCLUDE FILES SECTION ***********************************/ - -#include <linux/module.h> -#include <linux/sched.h> -#include <linux/errno.h> -#include <linux/kernel.h> -#include <linux/fs.h> -#include <linux/string.h> -#include <linux/init.h> -#include <linux/mutex.h> - -#include <asm/etraxi2c.h> - -#include <asm/io.h> -#include <asm/delay.h> - -#include "i2c.h" - -/****************** I2C DEFINITION SECTION *************************/ - -#define D(x) - -#define I2C_MAJOR 123 /* LOCAL/EXPERIMENTAL */ -static DEFINE_MUTEX(i2c_mutex); -static const char i2c_name[] = "i2c"; - -#define CLOCK_LOW_TIME 8 -#define CLOCK_HIGH_TIME 8 -#define START_CONDITION_HOLD_TIME 8 -#define STOP_CONDITION_HOLD_TIME 8 -#define ENABLE_OUTPUT 0x01 -#define ENABLE_INPUT 0x00 -#define I2C_CLOCK_HIGH 1 -#define I2C_CLOCK_LOW 0 -#define I2C_DATA_HIGH 1 -#define I2C_DATA_LOW 0 - -#define i2c_enable() -#define i2c_disable() - -/* enable or disable output-enable, to select output or input on the i2c bus */ - -#define i2c_dir_out() crisv32_io_set_dir(&cris_i2c_data, crisv32_io_dir_out) -#define i2c_dir_in() crisv32_io_set_dir(&cris_i2c_data, crisv32_io_dir_in) - -/* control the i2c clock and data signals */ - -#define i2c_clk(x) crisv32_io_set(&cris_i2c_clk, x) -#define i2c_data(x) crisv32_io_set(&cris_i2c_data, x) - -/* read a bit from the i2c interface */ - -#define i2c_getbit() crisv32_io_rd(&cris_i2c_data) - -#define i2c_delay(usecs) udelay(usecs) - -static DEFINE_SPINLOCK(i2c_lock); /* Protect directions etc */ - -/****************** VARIABLE SECTION ************************************/ - -static struct crisv32_iopin cris_i2c_clk; -static struct crisv32_iopin cris_i2c_data; - -/****************** FUNCTION DEFINITION SECTION *************************/ - - -/* generate i2c start condition */ - -void -i2c_start(void) -{ - /* - * SCL=1 SDA=1 - */ - i2c_dir_out(); - i2c_delay(CLOCK_HIGH_TIME/6); - i2c_data(I2C_DATA_HIGH); - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - /* - * SCL=1 SDA=0 - */ - i2c_data(I2C_DATA_LOW); - i2c_delay(START_CONDITION_HOLD_TIME); - /* - * SCL=0 SDA=0 - */ - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_LOW_TIME); -} - -/* generate i2c stop condition */ - -void -i2c_stop(void) -{ - i2c_dir_out(); - - /* - * SCL=0 SDA=0 - */ - i2c_clk(I2C_CLOCK_LOW); - i2c_data(I2C_DATA_LOW); - i2c_delay(CLOCK_LOW_TIME*2); - /* - * SCL=1 SDA=0 - */ - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME*2); - /* - * SCL=1 SDA=1 - */ - i2c_data(I2C_DATA_HIGH); - i2c_delay(STOP_CONDITION_HOLD_TIME); - - i2c_dir_in(); -} - -/* write a byte to the i2c interface */ - -void -i2c_outbyte(unsigned char x) -{ - int i; - - i2c_dir_out(); - - for (i = 0; i < 8; i++) { - if (x & 0x80) { - i2c_data(I2C_DATA_HIGH); - } else { - i2c_data(I2C_DATA_LOW); - } - - i2c_delay(CLOCK_LOW_TIME/2); - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_LOW_TIME/2); - x <<= 1; - } - i2c_data(I2C_DATA_LOW); - i2c_delay(CLOCK_LOW_TIME/2); - - /* - * enable input - */ - i2c_dir_in(); -} - -/* read a byte from the i2c interface */ - -unsigned char -i2c_inbyte(void) -{ - unsigned char aBitByte = 0; - int i; - - /* Switch off I2C to get bit */ - i2c_disable(); - i2c_dir_in(); - i2c_delay(CLOCK_HIGH_TIME/2); - - /* Get bit */ - aBitByte |= i2c_getbit(); - - /* Enable I2C */ - i2c_enable(); - i2c_delay(CLOCK_LOW_TIME/2); - - for (i = 1; i < 8; i++) { - aBitByte <<= 1; - /* Clock pulse */ - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_LOW_TIME); - - /* Switch off I2C to get bit */ - i2c_disable(); - i2c_dir_in(); - i2c_delay(CLOCK_HIGH_TIME/2); - - /* Get bit */ - aBitByte |= i2c_getbit(); - - /* Enable I2C */ - i2c_enable(); - i2c_delay(CLOCK_LOW_TIME/2); - } - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - - /* - * we leave the clock low, getbyte is usually followed - * by sendack/nack, they assume the clock to be low - */ - i2c_clk(I2C_CLOCK_LOW); - return aBitByte; -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: i2c_getack -*# -*# DESCRIPTION : checks if ack was received from ic2 -*# -*#--------------------------------------------------------------------------*/ - -int -i2c_getack(void) -{ - int ack = 1; - /* - * enable output - */ - i2c_dir_out(); - /* - * Release data bus by setting - * data high - */ - i2c_data(I2C_DATA_HIGH); - /* - * enable input - */ - i2c_dir_in(); - i2c_delay(CLOCK_HIGH_TIME/4); - /* - * generate ACK clock pulse - */ - i2c_clk(I2C_CLOCK_HIGH); -#if 0 - /* - * Use PORT PB instead of I2C - * for input. (I2C not working) - */ - i2c_clk(1); - i2c_data(1); - /* - * switch off I2C - */ - i2c_data(1); - i2c_disable(); - i2c_dir_in(); -#endif - - /* - * now wait for ack - */ - i2c_delay(CLOCK_HIGH_TIME/2); - /* - * check for ack - */ - if (i2c_getbit()) - ack = 0; - i2c_delay(CLOCK_HIGH_TIME/2); - if (!ack) { - if (!i2c_getbit()) /* receiver pulld SDA low */ - ack = 1; - i2c_delay(CLOCK_HIGH_TIME/2); - } - - /* - * our clock is high now, make sure data is low - * before we enable our output. If we keep data high - * and enable output, we would generate a stop condition. - */ -#if 0 - i2c_data(I2C_DATA_LOW); - - /* - * end clock pulse - */ - i2c_enable(); - i2c_dir_out(); -#endif - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_HIGH_TIME/4); - /* - * enable output - */ - i2c_dir_out(); - /* - * remove ACK clock pulse - */ - i2c_data(I2C_DATA_HIGH); - i2c_delay(CLOCK_LOW_TIME/2); - return ack; -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: I2C::sendAck -*# -*# DESCRIPTION : Send ACK on received data -*# -*#--------------------------------------------------------------------------*/ -void -i2c_sendack(void) -{ - /* - * enable output - */ - i2c_delay(CLOCK_LOW_TIME); - i2c_dir_out(); - /* - * set ack pulse high - */ - i2c_data(I2C_DATA_LOW); - /* - * generate clock pulse - */ - i2c_delay(CLOCK_HIGH_TIME/6); - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_LOW_TIME/6); - /* - * reset data out - */ - i2c_data(I2C_DATA_HIGH); - i2c_delay(CLOCK_LOW_TIME); - - i2c_dir_in(); -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: i2c_sendnack -*# -*# DESCRIPTION : Sends NACK on received data -*# -*#--------------------------------------------------------------------------*/ -void -i2c_sendnack(void) -{ - /* - * enable output - */ - i2c_delay(CLOCK_LOW_TIME); - i2c_dir_out(); - /* - * set data high - */ - i2c_data(I2C_DATA_HIGH); - /* - * generate clock pulse - */ - i2c_delay(CLOCK_HIGH_TIME/6); - i2c_clk(I2C_CLOCK_HIGH); - i2c_delay(CLOCK_HIGH_TIME); - i2c_clk(I2C_CLOCK_LOW); - i2c_delay(CLOCK_LOW_TIME); - - i2c_dir_in(); -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: i2c_write -*# -*# DESCRIPTION : Writes a value to an I2C device -*# -*#--------------------------------------------------------------------------*/ -int -i2c_write(unsigned char theSlave, void *data, size_t nbytes) -{ - int error, cntr = 3; - unsigned char bytes_wrote = 0; - unsigned char value; - unsigned long flags; - - spin_lock_irqsave(&i2c_lock, flags); - - do { - error = 0; - - i2c_start(); - /* - * send slave address - */ - i2c_outbyte((theSlave & 0xfe)); - /* - * wait for ack - */ - if (!i2c_getack()) - error = 1; - /* - * send data - */ - for (bytes_wrote = 0; bytes_wrote < nbytes; bytes_wrote++) { - memcpy(&value, data + bytes_wrote, sizeof value); - i2c_outbyte(value); - /* - * now it's time to wait for ack - */ - if (!i2c_getack()) - error |= 4; - } - /* - * end byte stream - */ - i2c_stop(); - - } while (error && cntr--); - - i2c_delay(CLOCK_LOW_TIME); - - spin_unlock_irqrestore(&i2c_lock, flags); - - return -error; -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: i2c_read -*# -*# DESCRIPTION : Reads a value from an I2C device -*# -*#--------------------------------------------------------------------------*/ -int -i2c_read(unsigned char theSlave, void *data, size_t nbytes) -{ - unsigned char b = 0; - unsigned char bytes_read = 0; - int error, cntr = 3; - unsigned long flags; - - spin_lock_irqsave(&i2c_lock, flags); - - do { - error = 0; - memset(data, 0, nbytes); - /* - * generate start condition - */ - i2c_start(); - /* - * send slave address - */ - i2c_outbyte((theSlave | 0x01)); - /* - * wait for ack - */ - if (!i2c_getack()) - error = 1; - /* - * fetch data - */ - for (bytes_read = 0; bytes_read < nbytes; bytes_read++) { - b = i2c_inbyte(); - memcpy(data + bytes_read, &b, sizeof b); - - if (bytes_read < (nbytes - 1)) - i2c_sendack(); - } - /* - * last received byte needs to be nacked - * instead of acked - */ - i2c_sendnack(); - /* - * end sequence - */ - i2c_stop(); - } while (error && cntr--); - - spin_unlock_irqrestore(&i2c_lock, flags); - - return -error; -} - -/*#--------------------------------------------------------------------------- -*# -*# FUNCTION NAME: i2c_writereg -*# -*# DESCRIPTION : Writes a value to an I2C device -*# -*#--------------------------------------------------------------------------*/ -int -i2c_writereg(unsigned char theSlave, unsigned char theReg, - unsigned char theValue) -{ - int error, cntr = 3; - unsigned long flags; - - spin_lock_irqsave(&i2c_lock, flags); - - do { - error = 0; - - 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(); - } while(error && cntr--); - - i2c_delay(CLOCK_LOW_TIME); - - spin_unlock_irqrestore(&i2c_lock, flags); - - 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_irqsave(&i2c_lock, flags); - - do { - error = 0; - /* - * 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 |= 2; - /* - * repeat start condition - */ - i2c_delay(CLOCK_LOW_TIME); - i2c_start(); - /* - * send slave address - */ - i2c_outbyte(theSlave | 0x01); - /* - * wait for ack - */ - if(!i2c_getack()) - error |= 4; - /* - * fetch register - */ - b = i2c_inbyte(); - /* - * last received byte needs to be nacked - * instead of acked - */ - i2c_sendnack(); - /* - * end sequence - */ - i2c_stop(); - - } while(error && cntr--); - - spin_unlock_irqrestore(&i2c_lock, flags); - - 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) -{ - int ret; - if(_IOC_TYPE(cmd) != ETRAXI2C_IOCTYPE) { - return -ENOTTY; - } - - switch (_IOC_NR(cmd)) { - case I2C_WRITEREG: - /* write to an i2c slave */ - D(printk("i2cw %d %d %d\n", - I2C_ARGSLAVE(arg), - I2C_ARGREG(arg), - I2C_ARGVALUE(arg))); - - mutex_lock(&i2c_mutex); - ret = i2c_writereg(I2C_ARGSLAVE(arg), - I2C_ARGREG(arg), - I2C_ARGVALUE(arg)); - mutex_unlock(&i2c_mutex); - return ret; - - case I2C_READREG: - { - unsigned char val; - /* read from an i2c slave */ - D(printk("i2cr %d %d ", - I2C_ARGSLAVE(arg), - I2C_ARGREG(arg))); - mutex_lock(&i2c_mutex); - val = i2c_readreg(I2C_ARGSLAVE(arg), I2C_ARGREG(arg)); - mutex_unlock(&i2c_mutex); - D(printk("= %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, -}; - -static int __init i2c_init(void) -{ - static int res; - static int first = 1; - - if (!first) - return res; - - first = 0; - - /* Setup and enable the DATA and CLK pins */ - - res = crisv32_io_get_name(&cris_i2c_data, - CONFIG_ETRAX_V32_I2C_DATA_PORT); - if (res < 0) - return res; - - res = crisv32_io_get_name(&cris_i2c_clk, CONFIG_ETRAX_V32_I2C_CLK_PORT); - crisv32_io_set_dir(&cris_i2c_clk, crisv32_io_dir_out); - - return res; -} - - -static int __init i2c_register(void) -{ - int res; - - res = i2c_init(); - if (res < 0) - return res; - - /* register char device */ - - 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) 1999-2007 Axis Communications AB\n"); - - return 0; -} -/* this makes sure that i2c_init is called during boot */ -module_init(i2c_register); - -/****************** END OF FILE i2c.c ********************************/ |