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Diffstat (limited to 'arch/arm/cpu/pxa/i2c.c')
-rw-r--r-- | arch/arm/cpu/pxa/i2c.c | 469 |
1 files changed, 0 insertions, 469 deletions
diff --git a/arch/arm/cpu/pxa/i2c.c b/arch/arm/cpu/pxa/i2c.c deleted file mode 100644 index 7aa49ae4a0..0000000000 --- a/arch/arm/cpu/pxa/i2c.c +++ /dev/null @@ -1,469 +0,0 @@ -/* - * (C) Copyright 2000 - * Paolo Scaffardi, AIRVENT SAM s.p.a - RIMINI(ITALY), arsenio@tin.it - * - * (C) Copyright 2000 Sysgo Real-Time Solutions, GmbH <www.elinos.com> - * Marius Groeger <mgroeger@sysgo.de> - * - * (C) Copyright 2003 Pengutronix e.K. - * Robert Schwebel <r.schwebel@pengutronix.de> - * - * See file CREDITS for list of people who contributed to this - * project. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of - * the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA - * - * Back ported to the 8xx platform (from the 8260 platform) by - * Murray.Jensen@cmst.csiro.au, 27-Jan-01. - */ - -/* FIXME: this file is PXA255 specific! What about other XScales? */ - -#include <common.h> -#include <asm/io.h> - -#ifdef CONFIG_HARD_I2C - -/* - * - CONFIG_SYS_I2C_SPEED - * - I2C_PXA_SLAVE_ADDR - */ - -#include <asm/arch/hardware.h> -#include <asm/arch/pxa-regs.h> -#include <i2c.h> - -/*#define DEBUG_I2C 1 /###* activate local debugging output */ -#define I2C_PXA_SLAVE_ADDR 0x1 /* slave pxa unit address */ - -#if (CONFIG_SYS_I2C_SPEED == 400000) -#define I2C_ICR_INIT (ICR_FM | ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE) -#else -#define I2C_ICR_INIT (ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE) -#endif - -#define I2C_ISR_INIT 0x7FF - -#ifdef DEBUG_I2C -#define PRINTD(x) printf x -#else -#define PRINTD(x) -#endif - - -/* Shall the current transfer have a start/stop condition? */ -#define I2C_COND_NORMAL 0 -#define I2C_COND_START 1 -#define I2C_COND_STOP 2 - -/* Shall the current transfer be ack/nacked or being waited for it? */ -#define I2C_ACKNAK_WAITACK 1 -#define I2C_ACKNAK_SENDACK 2 -#define I2C_ACKNAK_SENDNAK 4 - -/* Specify who shall transfer the data (master or slave) */ -#define I2C_READ 0 -#define I2C_WRITE 1 - -/* All transfers are described by this data structure */ -struct i2c_msg { - u8 condition; - u8 acknack; - u8 direction; - u8 data; -}; - - -/** - * i2c_pxa_reset: - reset the host controller - * - */ - -static void i2c_reset( void ) -{ - writel(readl(ICR) & ~ICR_IUE, ICR); /* disable unit */ - writel(readl(ICR) | ICR_UR, ICR); /* reset the unit */ - udelay(100); - writel(readl(ICR) & ~ICR_IUE, ICR); /* disable unit */ -#ifdef CONFIG_CPU_MONAHANS - /* | CKENB_1_PWM1 | CKENB_0_PWM0); */ - writel(readl(CKENB) | (CKENB_4_I2C), CKENB); -#else /* CONFIG_CPU_MONAHANS */ - /* set the global I2C clock on */ - writel(readl(CKEN) | CKEN14_I2C, CKEN); -#endif - writel(I2C_PXA_SLAVE_ADDR, ISAR); /* set our slave address */ - writel(I2C_ICR_INIT, ICR); /* set control reg values */ - writel(I2C_ISR_INIT, ISR); /* set clear interrupt bits */ - writel(readl(ICR) | ICR_IUE, ICR); /* enable unit */ - udelay(100); -} - - -/** - * i2c_isr_set_cleared: - wait until certain bits of the I2C status register - * are set and cleared - * - * @return: 1 in case of success, 0 means timeout (no match within 10 ms). - */ -static int i2c_isr_set_cleared( unsigned long set_mask, unsigned long cleared_mask ) -{ - int timeout = 10000; - - while( ((ISR & set_mask)!=set_mask) || ((ISR & cleared_mask)!=0) ){ - udelay( 10 ); - if( timeout-- < 0 ) return 0; - } - - return 1; -} - - -/** - * i2c_transfer: - Transfer one byte over the i2c bus - * - * This function can tranfer a byte over the i2c bus in both directions. - * It is used by the public API functions. - * - * @return: 0: transfer successful - * -1: message is empty - * -2: transmit timeout - * -3: ACK missing - * -4: receive timeout - * -5: illegal parameters - * -6: bus is busy and couldn't be aquired - */ -int i2c_transfer(struct i2c_msg *msg) -{ - int ret; - - if (!msg) - goto transfer_error_msg_empty; - - switch(msg->direction) { - - case I2C_WRITE: - - /* check if bus is not busy */ - if (!i2c_isr_set_cleared(0,ISR_IBB)) - goto transfer_error_bus_busy; - - /* start transmission */ - writel(readl(ICR) & ~ICR_START, ICR); - writel(readl(ICR) & ~ICR_STOP, ICR); - writel(msg->data, IDBR); - if (msg->condition == I2C_COND_START) - writel(readl(ICR) | ICR_START, ICR); - if (msg->condition == I2C_COND_STOP) - writel(readl(ICR) | ICR_STOP, ICR); - if (msg->acknack == I2C_ACKNAK_SENDNAK) - writel(readl(ICR) | ICR_ACKNAK, ICR); - if (msg->acknack == I2C_ACKNAK_SENDACK) - writel(readl(ICR) & ~ICR_ACKNAK, ICR); - writel(readl(ICR) & ~ICR_ALDIE, ICR); - writel(readl(ICR) | ICR_TB, ICR); - - /* transmit register empty? */ - if (!i2c_isr_set_cleared(ISR_ITE,0)) - goto transfer_error_transmit_timeout; - - /* clear 'transmit empty' state */ - writel(readl(ISR) | ISR_ITE, ISR); - - /* wait for ACK from slave */ - if (msg->acknack == I2C_ACKNAK_WAITACK) - if (!i2c_isr_set_cleared(0,ISR_ACKNAK)) - goto transfer_error_ack_missing; - break; - - case I2C_READ: - - /* check if bus is not busy */ - if (!i2c_isr_set_cleared(0,ISR_IBB)) - goto transfer_error_bus_busy; - - /* start receive */ - writel(readl(ICR) & ~ICR_START, ICR); - writel(readl(ICR) & ~ICR_STOP, ICR); - if (msg->condition == I2C_COND_START) - writel(readl(ICR) | ICR_START, ICR); - if (msg->condition == I2C_COND_STOP) - writel(readl(ICR) | ICR_STOP, ICR); - if (msg->acknack == I2C_ACKNAK_SENDNAK) - writel(readl(ICR) | ICR_ACKNAK, ICR); - if (msg->acknack == I2C_ACKNAK_SENDACK) - writel(readl(ICR) & ~ICR_ACKNAK, ICR); - writel(readl(ICR) & ~ICR_ALDIE, ICR); - writel(readl(ICR) | ICR_TB, ICR); - - /* receive register full? */ - if (!i2c_isr_set_cleared(ISR_IRF,0)) - goto transfer_error_receive_timeout; - - msg->data = readl(IDBR); - - /* clear 'receive empty' state */ - writel(readl(ISR) | ISR_IRF, ISR); - - break; - - default: - - goto transfer_error_illegal_param; - - } - - return 0; - -transfer_error_msg_empty: - PRINTD(("i2c_transfer: error: 'msg' is empty\n")); - ret = -1; goto i2c_transfer_finish; - -transfer_error_transmit_timeout: - PRINTD(("i2c_transfer: error: transmit timeout\n")); - ret = -2; goto i2c_transfer_finish; - -transfer_error_ack_missing: - PRINTD(("i2c_transfer: error: ACK missing\n")); - ret = -3; goto i2c_transfer_finish; - -transfer_error_receive_timeout: - PRINTD(("i2c_transfer: error: receive timeout\n")); - ret = -4; goto i2c_transfer_finish; - -transfer_error_illegal_param: - PRINTD(("i2c_transfer: error: illegal parameters\n")); - ret = -5; goto i2c_transfer_finish; - -transfer_error_bus_busy: - PRINTD(("i2c_transfer: error: bus is busy\n")); - ret = -6; goto i2c_transfer_finish; - -i2c_transfer_finish: - PRINTD(("i2c_transfer: ISR: 0x%04x\n",ISR)); - i2c_reset(); - return ret; - -} - -/* ------------------------------------------------------------------------ */ -/* API Functions */ -/* ------------------------------------------------------------------------ */ - -void i2c_init(int speed, int slaveaddr) -{ -#ifdef CONFIG_SYS_I2C_INIT_BOARD - /* call board specific i2c bus reset routine before accessing the */ - /* environment, which might be in a chip on that bus. For details */ - /* about this problem see doc/I2C_Edge_Conditions. */ - i2c_init_board(); -#endif -} - - -/** - * i2c_probe: - Test if a chip answers for a given i2c address - * - * @chip: address of the chip which is searched for - * @return: 0 if a chip was found, -1 otherwhise - */ - -int i2c_probe(uchar chip) -{ - struct i2c_msg msg; - - i2c_reset(); - - msg.condition = I2C_COND_START; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = (chip << 1) + 1; - if (i2c_transfer(&msg)) return -1; - - msg.condition = I2C_COND_STOP; - msg.acknack = I2C_ACKNAK_SENDNAK; - msg.direction = I2C_READ; - msg.data = 0x00; - if (i2c_transfer(&msg)) return -1; - - return 0; -} - - -/** - * i2c_read: - Read multiple bytes from an i2c device - * - * The higher level routines take into account that this function is only - * called with len < page length of the device (see configuration file) - * - * @chip: address of the chip which is to be read - * @addr: i2c data address within the chip - * @alen: length of the i2c data address (1..2 bytes) - * @buffer: where to write the data - * @len: how much byte do we want to read - * @return: 0 in case of success - */ - -int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) -{ - struct i2c_msg msg; - u8 addr_bytes[3]; /* lowest...highest byte of data address */ - int ret; - - PRINTD(("i2c_read(chip=0x%02x, addr=0x%02x, alen=0x%02x, len=0x%02x)\n",chip,addr,alen,len)); - - i2c_reset(); - - /* dummy chip address write */ - PRINTD(("i2c_read: dummy chip address write\n")); - msg.condition = I2C_COND_START; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = (chip << 1); - msg.data &= 0xFE; - if ((ret=i2c_transfer(&msg))) return -1; - - /* - * send memory address bytes; - * alen defines how much bytes we have to send. - */ - /*addr &= ((1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)-1); */ - addr_bytes[0] = (u8)((addr >> 0) & 0x000000FF); - addr_bytes[1] = (u8)((addr >> 8) & 0x000000FF); - addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF); - - while (--alen >= 0) { - - PRINTD(("i2c_read: send memory word address byte %1d\n",alen)); - msg.condition = I2C_COND_NORMAL; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = addr_bytes[alen]; - if ((ret=i2c_transfer(&msg))) return -1; - } - - - /* start read sequence */ - PRINTD(("i2c_read: start read sequence\n")); - msg.condition = I2C_COND_START; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = (chip << 1); - msg.data |= 0x01; - if ((ret=i2c_transfer(&msg))) return -1; - - /* read bytes; send NACK at last byte */ - while (len--) { - - if (len==0) { - msg.condition = I2C_COND_STOP; - msg.acknack = I2C_ACKNAK_SENDNAK; - } else { - msg.condition = I2C_COND_NORMAL; - msg.acknack = I2C_ACKNAK_SENDACK; - } - - msg.direction = I2C_READ; - msg.data = 0x00; - if ((ret=i2c_transfer(&msg))) return -1; - - *buffer = msg.data; - PRINTD(("i2c_read: reading byte (0x%08x)=0x%02x\n",(unsigned int)buffer,*buffer)); - buffer++; - - } - - i2c_reset(); - - return 0; -} - - -/** - * i2c_write: - Write multiple bytes to an i2c device - * - * The higher level routines take into account that this function is only - * called with len < page length of the device (see configuration file) - * - * @chip: address of the chip which is to be written - * @addr: i2c data address within the chip - * @alen: length of the i2c data address (1..2 bytes) - * @buffer: where to find the data to be written - * @len: how much byte do we want to read - * @return: 0 in case of success - */ - -int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) -{ - struct i2c_msg msg; - u8 addr_bytes[3]; /* lowest...highest byte of data address */ - - PRINTD(("i2c_write(chip=0x%02x, addr=0x%02x, alen=0x%02x, len=0x%02x)\n",chip,addr,alen,len)); - - i2c_reset(); - - /* chip address write */ - PRINTD(("i2c_write: chip address write\n")); - msg.condition = I2C_COND_START; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = (chip << 1); - msg.data &= 0xFE; - if (i2c_transfer(&msg)) return -1; - - /* - * send memory address bytes; - * alen defines how much bytes we have to send. - */ - addr_bytes[0] = (u8)((addr >> 0) & 0x000000FF); - addr_bytes[1] = (u8)((addr >> 8) & 0x000000FF); - addr_bytes[2] = (u8)((addr >> 16) & 0x000000FF); - - while (--alen >= 0) { - - PRINTD(("i2c_write: send memory word address\n")); - msg.condition = I2C_COND_NORMAL; - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = addr_bytes[alen]; - if (i2c_transfer(&msg)) return -1; - } - - /* write bytes; send NACK at last byte */ - while (len--) { - - PRINTD(("i2c_write: writing byte (0x%08x)=0x%02x\n",(unsigned int)buffer,*buffer)); - - if (len==0) - msg.condition = I2C_COND_STOP; - else - msg.condition = I2C_COND_NORMAL; - - msg.acknack = I2C_ACKNAK_WAITACK; - msg.direction = I2C_WRITE; - msg.data = *(buffer++); - - if (i2c_transfer(&msg)) return -1; - - } - - i2c_reset(); - - return 0; - -} - -#endif /* CONFIG_HARD_I2C */ |