diff options
Diffstat (limited to 'qemu/roms/u-boot/drivers/i2c/omap24xx_i2c.c')
| -rw-r--r-- | qemu/roms/u-boot/drivers/i2c/omap24xx_i2c.c | 680 |
1 files changed, 680 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/drivers/i2c/omap24xx_i2c.c b/qemu/roms/u-boot/drivers/i2c/omap24xx_i2c.c new file mode 100644 index 000000000..a39b5917e --- /dev/null +++ b/qemu/roms/u-boot/drivers/i2c/omap24xx_i2c.c @@ -0,0 +1,680 @@ +/* + * Basic I2C functions + * + * Copyright (c) 2004 Texas Instruments + * + * This package is free software; you can redistribute it and/or + * modify it under the terms of the license found in the file + * named COPYING that should have accompanied this file. + * + * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + * + * Author: Jian Zhang jzhang@ti.com, Texas Instruments + * + * Copyright (c) 2003 Wolfgang Denk, wd@denx.de + * Rewritten to fit into the current U-Boot framework + * + * Adapted for OMAP2420 I2C, r-woodruff2@ti.com + * + * Copyright (c) 2013 Lubomir Popov <lpopov@mm-sol.com>, MM Solutions + * New i2c_read, i2c_write and i2c_probe functions, tested on OMAP4 + * (4430/60/70), OMAP5 (5430) and AM335X (3359); should work on older + * OMAPs and derivatives as well. The only anticipated exception would + * be the OMAP2420, which shall require driver modification. + * - Rewritten i2c_read to operate correctly with all types of chips + * (old function could not read consistent data from some I2C slaves). + * - Optimized i2c_write. + * - New i2c_probe, performs write access vs read. The old probe could + * hang the system under certain conditions (e.g. unconfigured pads). + * - The read/write/probe functions try to identify unconfigured bus. + * - Status functions now read irqstatus_raw as per TRM guidelines + * (except for OMAP243X and OMAP34XX). + * - Driver now supports up to I2C5 (OMAP5). + * + * Copyright (c) 2014 Hannes Petermaier <oe5hpm@oevsv.at>, B&R + * - Added support for set_speed + * + */ + +#include <common.h> +#include <i2c.h> + +#include <asm/arch/i2c.h> +#include <asm/io.h> + +#include "omap24xx_i2c.h" + +DECLARE_GLOBAL_DATA_PTR; + +#define I2C_TIMEOUT 1000 + +/* Absolutely safe for status update at 100 kHz I2C: */ +#define I2C_WAIT 200 + +static int wait_for_bb(struct i2c_adapter *adap); +static struct i2c *omap24_get_base(struct i2c_adapter *adap); +static u16 wait_for_event(struct i2c_adapter *adap); +static void flush_fifo(struct i2c_adapter *adap); +static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed) +{ + unsigned int sampleclk, prescaler; + int fsscll, fssclh; + + speed <<= 1; + prescaler = 0; + /* + * some divisors may cause a precission loss, but shouldn't + * be a big thing, because i2c_clk is then allready very slow. + */ + while (prescaler <= 0xFF) { + sampleclk = I2C_IP_CLK / (prescaler+1); + + fsscll = sampleclk / speed; + fssclh = fsscll; + fsscll -= I2C_FASTSPEED_SCLL_TRIM; + fssclh -= I2C_FASTSPEED_SCLH_TRIM; + + if (((fsscll > 0) && (fssclh > 0)) && + ((fsscll <= (255-I2C_FASTSPEED_SCLL_TRIM)) && + (fssclh <= (255-I2C_FASTSPEED_SCLH_TRIM)))) { + if (pscl) + *pscl = fsscll; + if (psch) + *psch = fssclh; + + return prescaler; + } + prescaler++; + } + return -1; +} +static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int psc, fsscll = 0, fssclh = 0; + int hsscll = 0, hssclh = 0; + u32 scll = 0, sclh = 0; + + if (speed >= OMAP_I2C_HIGH_SPEED) { + /* High speed */ + psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK; + psc -= 1; + if (psc < I2C_PSC_MIN) { + printf("Error : I2C unsupported prescaler %d\n", psc); + return -1; + } + + /* For first phase of HS mode */ + fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed); + + fssclh = fsscll; + + fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM; + fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM; + if (((fsscll < 0) || (fssclh < 0)) || + ((fsscll > 255) || (fssclh > 255))) { + puts("Error : I2C initializing first phase clock\n"); + return -1; + } + + /* For second phase of HS mode */ + hsscll = hssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed); + + hsscll -= I2C_HIGHSPEED_PHASE_TWO_SCLL_TRIM; + hssclh -= I2C_HIGHSPEED_PHASE_TWO_SCLH_TRIM; + if (((fsscll < 0) || (fssclh < 0)) || + ((fsscll > 255) || (fssclh > 255))) { + puts("Error : I2C initializing second phase clock\n"); + return -1; + } + + scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll; + sclh = (unsigned int)hssclh << 8 | (unsigned int)fssclh; + + } else { + /* Standard and fast speed */ + psc = omap24_i2c_findpsc(&scll, &sclh, speed); + if (0 > psc) { + puts("Error : I2C initializing clock\n"); + return -1; + } + } + + adap->speed = speed; + adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */ + writew(0, &i2c_base->con); + writew(psc, &i2c_base->psc); + writew(scll, &i2c_base->scll); + writew(sclh, &i2c_base->sclh); + writew(I2C_CON_EN, &i2c_base->con); + writew(0xFFFF, &i2c_base->stat); /* clear all pending status */ + + return 0; +} +static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int timeout = I2C_TIMEOUT; + + if (readw(&i2c_base->con) & I2C_CON_EN) { + writew(0, &i2c_base->con); + udelay(50000); + } + + writew(0x2, &i2c_base->sysc); /* for ES2 after soft reset */ + udelay(1000); + + writew(I2C_CON_EN, &i2c_base->con); + while (!(readw(&i2c_base->syss) & I2C_SYSS_RDONE) && timeout--) { + if (timeout <= 0) { + puts("ERROR: Timeout in soft-reset\n"); + return; + } + udelay(1000); + } + + if (0 != omap24_i2c_setspeed(adap, speed)) { + printf("ERROR: failed to setup I2C bus-speed!\n"); + return; + } + + /* own address */ + writew(slaveadd, &i2c_base->oa); + +#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) + /* + * Have to enable interrupts for OMAP2/3, these IPs don't have + * an 'irqstatus_raw' register and we shall have to poll 'stat' + */ + writew(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE | + I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie); +#endif + udelay(1000); + flush_fifo(adap); + writew(0xFFFF, &i2c_base->stat); +} + +static void flush_fifo(struct i2c_adapter *adap) +{ + struct i2c *i2c_base = omap24_get_base(adap); + u16 stat; + + /* + * note: if you try and read data when its not there or ready + * you get a bus error + */ + while (1) { + stat = readw(&i2c_base->stat); + if (stat == I2C_STAT_RRDY) { + readb(&i2c_base->data); + writew(I2C_STAT_RRDY, &i2c_base->stat); + udelay(1000); + } else + break; + } +} + +/* + * i2c_probe: Use write access. Allows to identify addresses that are + * write-only (like the config register of dual-port EEPROMs) + */ +static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip) +{ + struct i2c *i2c_base = omap24_get_base(adap); + u16 status; + int res = 1; /* default = fail */ + + if (chip == readw(&i2c_base->oa)) + return res; + + /* Wait until bus is free */ + if (wait_for_bb(adap)) + return res; + + /* No data transfer, slave addr only */ + writew(chip, &i2c_base->sa); + /* Stop bit needed here */ + writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX | + I2C_CON_STP, &i2c_base->con); + + status = wait_for_event(adap); + + if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) { + /* + * With current high-level command implementation, notifying + * the user shall flood the console with 127 messages. If + * silent exit is desired upon unconfigured bus, remove the + * following 'if' section: + */ + if (status == I2C_STAT_XRDY) + printf("i2c_probe: pads on bus %d probably not configured (status=0x%x)\n", + adap->hwadapnr, status); + + goto pr_exit; + } + + /* Check for ACK (!NAK) */ + if (!(status & I2C_STAT_NACK)) { + res = 0; /* Device found */ + udelay(adap->waitdelay);/* Required by AM335X in SPL */ + /* Abort transfer (force idle state) */ + writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */ + udelay(1000); + writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX | + I2C_CON_STP, &i2c_base->con); /* STP */ + } +pr_exit: + flush_fifo(adap); + writew(0xFFFF, &i2c_base->stat); + return res; +} + +/* + * i2c_read: Function now uses a single I2C read transaction with bulk transfer + * of the requested number of bytes (note that the 'i2c md' command + * limits this to 16 bytes anyway). If CONFIG_I2C_REPEATED_START is + * defined in the board config header, this transaction shall be with + * Repeated Start (Sr) between the address and data phases; otherwise + * Stop-Start (P-S) shall be used (some I2C chips do require a P-S). + * The address (reg offset) may be 0, 1 or 2 bytes long. + * Function now reads correctly from chips that return more than one + * byte of data per addressed register (like TI temperature sensors), + * or that do not need a register address at all (such as some clock + * distributors). + */ +static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr, + int alen, uchar *buffer, int len) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int i2c_error = 0; + u16 status; + + if (alen < 0) { + puts("I2C read: addr len < 0\n"); + return 1; + } + if (len < 0) { + puts("I2C read: data len < 0\n"); + return 1; + } + if (buffer == NULL) { + puts("I2C read: NULL pointer passed\n"); + return 1; + } + + if (alen > 2) { + printf("I2C read: addr len %d not supported\n", alen); + return 1; + } + + if (addr + len > (1 << 16)) { + puts("I2C read: address out of range\n"); + return 1; + } + + /* Wait until bus not busy */ + if (wait_for_bb(adap)) + return 1; + + /* Zero, one or two bytes reg address (offset) */ + writew(alen, &i2c_base->cnt); + /* Set slave address */ + writew(chip, &i2c_base->sa); + + if (alen) { + /* Must write reg offset first */ +#ifdef CONFIG_I2C_REPEATED_START + /* No stop bit, use Repeated Start (Sr) */ + writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | + I2C_CON_TRX, &i2c_base->con); +#else + /* Stop - Start (P-S) */ + writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP | + I2C_CON_TRX, &i2c_base->con); +#endif + /* Send register offset */ + while (1) { + status = wait_for_event(adap); + /* Try to identify bus that is not padconf'd for I2C */ + if (status == I2C_STAT_XRDY) { + i2c_error = 2; + printf("i2c_read (addr phase): pads on bus %d probably not configured (status=0x%x)\n", + adap->hwadapnr, status); + goto rd_exit; + } + if (status == 0 || (status & I2C_STAT_NACK)) { + i2c_error = 1; + printf("i2c_read: error waiting for addr ACK (status=0x%x)\n", + status); + goto rd_exit; + } + if (alen) { + if (status & I2C_STAT_XRDY) { + alen--; + /* Do we have to use byte access? */ + writeb((addr >> (8 * alen)) & 0xff, + &i2c_base->data); + writew(I2C_STAT_XRDY, &i2c_base->stat); + } + } + if (status & I2C_STAT_ARDY) { + writew(I2C_STAT_ARDY, &i2c_base->stat); + break; + } + } + } + /* Set slave address */ + writew(chip, &i2c_base->sa); + /* Read len bytes from slave */ + writew(len, &i2c_base->cnt); + /* Need stop bit here */ + writew(I2C_CON_EN | I2C_CON_MST | + I2C_CON_STT | I2C_CON_STP, + &i2c_base->con); + + /* Receive data */ + while (1) { + status = wait_for_event(adap); + /* + * Try to identify bus that is not padconf'd for I2C. This + * state could be left over from previous transactions if + * the address phase is skipped due to alen=0. + */ + if (status == I2C_STAT_XRDY) { + i2c_error = 2; + printf("i2c_read (data phase): pads on bus %d probably not configured (status=0x%x)\n", + adap->hwadapnr, status); + goto rd_exit; + } + if (status == 0 || (status & I2C_STAT_NACK)) { + i2c_error = 1; + goto rd_exit; + } + if (status & I2C_STAT_RRDY) { + *buffer++ = readb(&i2c_base->data); + writew(I2C_STAT_RRDY, &i2c_base->stat); + } + if (status & I2C_STAT_ARDY) { + writew(I2C_STAT_ARDY, &i2c_base->stat); + break; + } + } + +rd_exit: + flush_fifo(adap); + writew(0xFFFF, &i2c_base->stat); + return i2c_error; +} + +/* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */ +static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr, + int alen, uchar *buffer, int len) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int i; + u16 status; + int i2c_error = 0; + int timeout = I2C_TIMEOUT; + + if (alen < 0) { + puts("I2C write: addr len < 0\n"); + return 1; + } + + if (len < 0) { + puts("I2C write: data len < 0\n"); + return 1; + } + + if (buffer == NULL) { + puts("I2C write: NULL pointer passed\n"); + return 1; + } + + if (alen > 2) { + printf("I2C write: addr len %d not supported\n", alen); + return 1; + } + + if (addr + len > (1 << 16)) { + printf("I2C write: address 0x%x + 0x%x out of range\n", + addr, len); + return 1; + } + + /* Wait until bus not busy */ + if (wait_for_bb(adap)) + return 1; + + /* Start address phase - will write regoffset + len bytes data */ + writew(alen + len, &i2c_base->cnt); + /* Set slave address */ + writew(chip, &i2c_base->sa); + /* Stop bit needed here */ + writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX | + I2C_CON_STP, &i2c_base->con); + + while (alen) { + /* Must write reg offset (one or two bytes) */ + status = wait_for_event(adap); + /* Try to identify bus that is not padconf'd for I2C */ + if (status == I2C_STAT_XRDY) { + i2c_error = 2; + printf("i2c_write: pads on bus %d probably not configured (status=0x%x)\n", + adap->hwadapnr, status); + goto wr_exit; + } + if (status == 0 || (status & I2C_STAT_NACK)) { + i2c_error = 1; + printf("i2c_write: error waiting for addr ACK (status=0x%x)\n", + status); + goto wr_exit; + } + if (status & I2C_STAT_XRDY) { + alen--; + writeb((addr >> (8 * alen)) & 0xff, &i2c_base->data); + writew(I2C_STAT_XRDY, &i2c_base->stat); + } else { + i2c_error = 1; + printf("i2c_write: bus not ready for addr Tx (status=0x%x)\n", + status); + goto wr_exit; + } + } + /* Address phase is over, now write data */ + for (i = 0; i < len; i++) { + status = wait_for_event(adap); + if (status == 0 || (status & I2C_STAT_NACK)) { + i2c_error = 1; + printf("i2c_write: error waiting for data ACK (status=0x%x)\n", + status); + goto wr_exit; + } + if (status & I2C_STAT_XRDY) { + writeb(buffer[i], &i2c_base->data); + writew(I2C_STAT_XRDY, &i2c_base->stat); + } else { + i2c_error = 1; + printf("i2c_write: bus not ready for data Tx (i=%d)\n", + i); + goto wr_exit; + } + } + /* + * poll ARDY bit for making sure that last byte really has been + * transferred on the bus. + */ + do { + status = wait_for_event(adap); + } while (!(status & I2C_STAT_ARDY) && timeout--); + if (timeout <= 0) + printf("i2c_write: timed out writig last byte!\n"); + +wr_exit: + flush_fifo(adap); + writew(0xFFFF, &i2c_base->stat); + return i2c_error; +} + +/* + * Wait for the bus to be free by checking the Bus Busy (BB) + * bit to become clear + */ +static int wait_for_bb(struct i2c_adapter *adap) +{ + struct i2c *i2c_base = omap24_get_base(adap); + int timeout = I2C_TIMEOUT; + u16 stat; + + writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/ +#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) + while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) { +#else + /* Read RAW status */ + while ((stat = readw(&i2c_base->irqstatus_raw) & + I2C_STAT_BB) && timeout--) { +#endif + writew(stat, &i2c_base->stat); + udelay(adap->waitdelay); + } + + if (timeout <= 0) { + printf("Timed out in wait_for_bb: status=%04x\n", + stat); + return 1; + } + writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/ + return 0; +} + +/* + * Wait for the I2C controller to complete current action + * and update status + */ +static u16 wait_for_event(struct i2c_adapter *adap) +{ + struct i2c *i2c_base = omap24_get_base(adap); + u16 status; + int timeout = I2C_TIMEOUT; + + do { + udelay(adap->waitdelay); +#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) + status = readw(&i2c_base->stat); +#else + /* Read RAW status */ + status = readw(&i2c_base->irqstatus_raw); +#endif + } while (!(status & + (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY | + I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK | + I2C_STAT_AL)) && timeout--); + + if (timeout <= 0) { + printf("Timed out in wait_for_event: status=%04x\n", + status); + /* + * If status is still 0 here, probably the bus pads have + * not been configured for I2C, and/or pull-ups are missing. + */ + printf("Check if pads/pull-ups of bus %d are properly configured\n", + adap->hwadapnr); + writew(0xFFFF, &i2c_base->stat); + status = 0; + } + + return status; +} + +static struct i2c *omap24_get_base(struct i2c_adapter *adap) +{ + switch (adap->hwadapnr) { + case 0: + return (struct i2c *)I2C_BASE1; + break; + case 1: + return (struct i2c *)I2C_BASE2; + break; +#if (I2C_BUS_MAX > 2) + case 2: + return (struct i2c *)I2C_BASE3; + break; +#if (I2C_BUS_MAX > 3) + case 3: + return (struct i2c *)I2C_BASE4; + break; +#if (I2C_BUS_MAX > 4) + case 4: + return (struct i2c *)I2C_BASE5; + break; +#endif +#endif +#endif + default: + printf("wrong hwadapnr: %d\n", adap->hwadapnr); + break; + } + return NULL; +} + +#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1) +#define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED +#endif +#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1) +#define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE +#endif + +U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe, + omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed, + CONFIG_SYS_OMAP24_I2C_SPEED, + CONFIG_SYS_OMAP24_I2C_SLAVE, + 0) +U_BOOT_I2C_ADAP_COMPLETE(omap24_1, omap24_i2c_init, omap24_i2c_probe, + omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed, + CONFIG_SYS_OMAP24_I2C_SPEED1, + CONFIG_SYS_OMAP24_I2C_SLAVE1, + 1) +#if (I2C_BUS_MAX > 2) +#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED2) +#define CONFIG_SYS_OMAP24_I2C_SPEED2 CONFIG_SYS_OMAP24_I2C_SPEED +#endif +#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE2) +#define CONFIG_SYS_OMAP24_I2C_SLAVE2 CONFIG_SYS_OMAP24_I2C_SLAVE +#endif + +U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe, + omap24_i2c_read, omap24_i2c_write, NULL, + CONFIG_SYS_OMAP24_I2C_SPEED2, + CONFIG_SYS_OMAP24_I2C_SLAVE2, + 2) +#if (I2C_BUS_MAX > 3) +#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED3) +#define CONFIG_SYS_OMAP24_I2C_SPEED3 CONFIG_SYS_OMAP24_I2C_SPEED +#endif +#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE3) +#define CONFIG_SYS_OMAP24_I2C_SLAVE3 CONFIG_SYS_OMAP24_I2C_SLAVE +#endif + +U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe, + omap24_i2c_read, omap24_i2c_write, NULL, + CONFIG_SYS_OMAP24_I2C_SPEED3, + CONFIG_SYS_OMAP24_I2C_SLAVE3, + 3) +#if (I2C_BUS_MAX > 4) +#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED4) +#define CONFIG_SYS_OMAP24_I2C_SPEED4 CONFIG_SYS_OMAP24_I2C_SPEED +#endif +#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE4) +#define CONFIG_SYS_OMAP24_I2C_SLAVE4 CONFIG_SYS_OMAP24_I2C_SLAVE +#endif + +U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe, + omap24_i2c_read, omap24_i2c_write, NULL, + CONFIG_SYS_OMAP24_I2C_SPEED4, + CONFIG_SYS_OMAP24_I2C_SLAVE4, + 4) +#endif +#endif +#endif |