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u-boot/drivers/i2c/omap24xx_i2c.c
Nikita Yushchenko a064e0c75f ti: i2c: fix probe_chip() return value 
Per documentation, dm_i2c_ops.probe_chip() shall return -EREMOTEIO if
probe fails.

Currently, omap_i2c_probe_chip() returns 1 instead. Fix that.

Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
2022-02-21 08:39:52 -05:00

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/*
* 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 Schmelzer <oe5hpm@oevsv.at>, B&R
* - Added support for set_speed
*
*/
#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <log.h>
#include <linux/delay.h>
#include <asm/io.h>
#include <asm/omap_i2c.h>
/*
* Provide access to architecture-specific I2C header files for platforms
* that are NOT yet solely relying on CONFIG_DM_I2C, CONFIG_OF_CONTROL, and
* the defaults provided in 'omap24xx_i2c.h' for all U-Boot stages where I2C
* access is desired.
*/
#ifndef CONFIG_ARCH_K3
#include <asm/arch/i2c.h>
#endif
#include "omap24xx_i2c.h"
#define I2C_TIMEOUT 1000
/* Absolutely safe for status update at 100 kHz I2C: */
#define I2C_WAIT 200
enum {
OMAP_I2C_REV_REG = 0, /* Only on IP V1 (OMAP34XX) */
OMAP_I2C_IE_REG, /* Only on IP V1 (OMAP34XX) */
OMAP_I2C_STAT_REG,
OMAP_I2C_WE_REG,
OMAP_I2C_SYSS_REG,
OMAP_I2C_BUF_REG,
OMAP_I2C_CNT_REG,
OMAP_I2C_DATA_REG,
OMAP_I2C_SYSC_REG,
OMAP_I2C_CON_REG,
OMAP_I2C_OA_REG,
OMAP_I2C_SA_REG,
OMAP_I2C_PSC_REG,
OMAP_I2C_SCLL_REG,
OMAP_I2C_SCLH_REG,
OMAP_I2C_SYSTEST_REG,
OMAP_I2C_BUFSTAT_REG,
/* Only on IP V2 (OMAP4430, etc.) */
OMAP_I2C_IP_V2_REVNB_LO,
OMAP_I2C_IP_V2_REVNB_HI,
OMAP_I2C_IP_V2_IRQSTATUS_RAW,
OMAP_I2C_IP_V2_IRQENABLE_SET,
OMAP_I2C_IP_V2_IRQENABLE_CLR,
};
static const u8 __maybe_unused reg_map_ip_v1[] = {
[OMAP_I2C_REV_REG] = 0x00,
[OMAP_I2C_IE_REG] = 0x04,
[OMAP_I2C_STAT_REG] = 0x08,
[OMAP_I2C_WE_REG] = 0x0c,
[OMAP_I2C_SYSS_REG] = 0x10,
[OMAP_I2C_BUF_REG] = 0x14,
[OMAP_I2C_CNT_REG] = 0x18,
[OMAP_I2C_DATA_REG] = 0x1c,
[OMAP_I2C_SYSC_REG] = 0x20,
[OMAP_I2C_CON_REG] = 0x24,
[OMAP_I2C_OA_REG] = 0x28,
[OMAP_I2C_SA_REG] = 0x2c,
[OMAP_I2C_PSC_REG] = 0x30,
[OMAP_I2C_SCLL_REG] = 0x34,
[OMAP_I2C_SCLH_REG] = 0x38,
[OMAP_I2C_SYSTEST_REG] = 0x3c,
[OMAP_I2C_BUFSTAT_REG] = 0x40,
};
static const u8 __maybe_unused reg_map_ip_v2[] = {
[OMAP_I2C_STAT_REG] = 0x28,
[OMAP_I2C_WE_REG] = 0x34,
[OMAP_I2C_SYSS_REG] = 0x90,
[OMAP_I2C_BUF_REG] = 0x94,
[OMAP_I2C_CNT_REG] = 0x98,
[OMAP_I2C_DATA_REG] = 0x9c,
[OMAP_I2C_SYSC_REG] = 0x10,
[OMAP_I2C_CON_REG] = 0xa4,
[OMAP_I2C_OA_REG] = 0xa8,
[OMAP_I2C_SA_REG] = 0xac,
[OMAP_I2C_PSC_REG] = 0xb0,
[OMAP_I2C_SCLL_REG] = 0xb4,
[OMAP_I2C_SCLH_REG] = 0xb8,
[OMAP_I2C_SYSTEST_REG] = 0xbc,
[OMAP_I2C_BUFSTAT_REG] = 0xc0,
[OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
[OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
[OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
[OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
[OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
};
struct omap_i2c {
struct udevice *clk;
int ip_rev;
struct i2c *regs;
unsigned int speed;
int waitdelay;
int clk_id;
};
static inline const u8 *omap_i2c_get_ip_reg_map(int ip_rev)
{
switch (ip_rev) {
case OMAP_I2C_REV_V1:
return reg_map_ip_v1;
case OMAP_I2C_REV_V2:
/* Fall through... */
default:
return reg_map_ip_v2;
}
}
static inline void omap_i2c_write_reg(void __iomem *base, int ip_rev,
u16 val, int reg)
{
writew(val, base + omap_i2c_get_ip_reg_map(ip_rev)[reg]);
}
static inline u16 omap_i2c_read_reg(void __iomem *base, int ip_rev, int reg)
{
return readw(base + omap_i2c_get_ip_reg_map(ip_rev)[reg]);
}
static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
{
unsigned long internal_clk = 0, fclk;
unsigned int prescaler;
/*
* This method is only called for Standard and Fast Mode speeds
*
* For some TI SoCs it is explicitly written in TRM (e,g, SPRUHZ6G,
* page 5685, Table 24-7)
* that the internal I2C clock (after prescaler) should be between
* 7-12 MHz (at least for Fast Mode (FS)).
*
* Such approach is used in v4.9 Linux kernel in:
* ./drivers/i2c/busses/i2c-omap.c (omap_i2c_init function).
*/
speed /= 1000; /* convert speed to kHz */
if (speed > 100)
internal_clk = 9600;
else
internal_clk = 4000;
fclk = I2C_IP_CLK / 1000;
prescaler = fclk / internal_clk;
prescaler = prescaler - 1;
if (speed > 100) {
unsigned long scl;
/* Fast mode */
scl = internal_clk / speed;
*pscl = scl - (scl / 3) - I2C_FASTSPEED_SCLL_TRIM;
*psch = (scl / 3) - I2C_FASTSPEED_SCLH_TRIM;
} else {
/* Standard mode */
*pscl = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLL_TRIM;
*psch = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLH_TRIM;
}
debug("%s: speed [kHz]: %d psc: 0x%x sscl: 0x%x ssch: 0x%x\n",
__func__, speed, prescaler, *pscl, *psch);
if (*pscl <= 0 || *psch <= 0 || prescaler <= 0)
return -EINVAL;
return prescaler;
}
/*
* Wait for the bus to be free by checking the Bus Busy (BB)
* bit to become clear
*/
static int wait_for_bb(void __iomem *i2c_base, int ip_rev, int waitdelay)
{
int timeout = I2C_TIMEOUT;
int irq_stat_reg;
u16 stat;
irq_stat_reg = (ip_rev == OMAP_I2C_REV_V1) ?
OMAP_I2C_STAT_REG : OMAP_I2C_IP_V2_IRQSTATUS_RAW;
/* clear current interrupts */
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
while ((stat = omap_i2c_read_reg(i2c_base, ip_rev, irq_stat_reg) &
I2C_STAT_BB) && timeout--) {
omap_i2c_write_reg(i2c_base, ip_rev, stat, OMAP_I2C_STAT_REG);
udelay(waitdelay);
}
if (timeout <= 0) {
printf("Timed out in %s: status=%04x\n", __func__, stat);
return 1;
}
/* clear delayed stuff */
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
return 0;
}
/*
* Wait for the I2C controller to complete current action
* and update status
*/
static u16 wait_for_event(void __iomem *i2c_base, int ip_rev, int waitdelay)
{
u16 status;
int timeout = I2C_TIMEOUT;
int irq_stat_reg;
irq_stat_reg = (ip_rev == OMAP_I2C_REV_V1) ?
OMAP_I2C_STAT_REG : OMAP_I2C_IP_V2_IRQSTATUS_RAW;
do {
udelay(waitdelay);
status = omap_i2c_read_reg(i2c_base, ip_rev, irq_stat_reg);
} 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 %s: status=%04x\n", __func__, 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 are properly configured\n");
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
status = 0;
}
return status;
}
static void flush_fifo(void __iomem *i2c_base, int ip_rev)
{
u16 stat;
/*
* note: if you try and read data when its not there or ready
* you get a bus error
*/
while (1) {
stat = omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_STAT_REG);
if (stat == I2C_STAT_RRDY) {
omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_DATA_REG);
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_RRDY, OMAP_I2C_STAT_REG);
udelay(1000);
} else
break;
}
}
static int __omap24_i2c_setspeed(void __iomem *i2c_base, int ip_rev, uint speed,
int *waitdelay)
{
int psc, fsscll = 0, fssclh = 0;
int hsscll = 0, hssclh = 0;
u32 scll = 0, sclh = 0;
if (speed >= I2C_SPEED_HIGH_RATE) {
/* 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;
}
}
/* wait for 20 clkperiods */
*waitdelay = (10000000 / speed) * 2;
omap_i2c_write_reg(i2c_base, ip_rev, 0, OMAP_I2C_CON_REG);
omap_i2c_write_reg(i2c_base, ip_rev, psc, OMAP_I2C_PSC_REG);
omap_i2c_write_reg(i2c_base, ip_rev, scll, OMAP_I2C_SCLL_REG);
omap_i2c_write_reg(i2c_base, ip_rev, sclh, OMAP_I2C_SCLH_REG);
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN, OMAP_I2C_CON_REG);
/* clear all pending status */
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
return 0;
}
static void omap24_i2c_deblock(void __iomem *i2c_base, int ip_rev)
{
int i;
u16 systest;
u16 orgsystest;
/* set test mode ST_EN = 1 */
orgsystest = omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_SYSTEST_REG);
systest = orgsystest;
/* enable testmode */
systest |= I2C_SYSTEST_ST_EN;
omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
systest &= ~I2C_SYSTEST_TMODE_MASK;
systest |= 3 << I2C_SYSTEST_TMODE_SHIFT;
omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
/* set SCL, SDA = 1 */
systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
udelay(10);
/* toggle scl 9 clocks */
for (i = 0; i < 9; i++) {
/* SCL = 0 */
systest &= ~I2C_SYSTEST_SCL_O;
omap_i2c_write_reg(i2c_base, ip_rev,
systest, OMAP_I2C_SYSTEST_REG);
udelay(10);
/* SCL = 1 */
systest |= I2C_SYSTEST_SCL_O;
omap_i2c_write_reg(i2c_base, ip_rev,
systest, OMAP_I2C_SYSTEST_REG);
udelay(10);
}
/* send stop */
systest &= ~I2C_SYSTEST_SDA_O;
omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
udelay(10);
systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
omap_i2c_write_reg(i2c_base, ip_rev, systest, OMAP_I2C_SYSTEST_REG);
udelay(10);
/* restore original mode */
omap_i2c_write_reg(i2c_base, ip_rev, orgsystest, OMAP_I2C_SYSTEST_REG);
}
static void __omap24_i2c_init(void __iomem *i2c_base, int ip_rev, int speed,
int slaveadd, int *waitdelay)
{
int timeout = I2C_TIMEOUT;
int deblock = 1;
retry:
if (omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_CON_REG) &
I2C_CON_EN) {
omap_i2c_write_reg(i2c_base, ip_rev, 0, OMAP_I2C_CON_REG);
udelay(50000);
}
/* for ES2 after soft reset */
omap_i2c_write_reg(i2c_base, ip_rev, 0x2, OMAP_I2C_SYSC_REG);
udelay(1000);
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN, OMAP_I2C_CON_REG);
while (!(omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_SYSS_REG) &
I2C_SYSS_RDONE) && timeout--) {
if (timeout <= 0) {
puts("ERROR: Timeout in soft-reset\n");
return;
}
udelay(1000);
}
if (__omap24_i2c_setspeed(i2c_base, ip_rev, speed, waitdelay)) {
printf("ERROR: failed to setup I2C bus-speed!\n");
return;
}
/* own address */
omap_i2c_write_reg(i2c_base, ip_rev, slaveadd, OMAP_I2C_OA_REG);
if (ip_rev == OMAP_I2C_REV_V1) {
/*
* Have to enable interrupts for OMAP2/3, these IPs don't have
* an 'irqstatus_raw' register and we shall have to poll 'stat'
*/
omap_i2c_write_reg(i2c_base, ip_rev, I2C_IE_XRDY_IE |
I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
I2C_IE_NACK_IE | I2C_IE_AL_IE,
OMAP_I2C_IE_REG);
}
udelay(1000);
flush_fifo(i2c_base, ip_rev);
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
/* Handle possible failed I2C state */
if (wait_for_bb(i2c_base, ip_rev, *waitdelay))
if (deblock == 1) {
omap24_i2c_deblock(i2c_base, ip_rev);
deblock = 0;
goto retry;
}
}
/*
* 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(void __iomem *i2c_base, int ip_rev, int waitdelay,
uchar chip)
{
u16 status;
int res = 1; /* default = fail */
if (chip == omap_i2c_read_reg(i2c_base, ip_rev, OMAP_I2C_OA_REG))
return res;
/* Wait until bus is free */
if (wait_for_bb(i2c_base, ip_rev, waitdelay))
return res;
/* No data transfer, slave addr only */
omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
/* Stop bit needed here */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_STT | I2C_CON_TRX | I2C_CON_STP,
OMAP_I2C_CON_REG);
status = wait_for_event(i2c_base, ip_rev, waitdelay);
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 probably not configured (status=0x%x)\n",
status);
goto pr_exit;
}
/* Check for ACK (!NAK) */
if (!(status & I2C_STAT_NACK)) {
res = 0; /* Device found */
udelay(waitdelay);/* Required by AM335X in SPL */
/* Abort transfer (force idle state) */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_MST | I2C_CON_TRX,
OMAP_I2C_CON_REG); /* Reset */
udelay(1000);
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_TRX | I2C_CON_STP,
OMAP_I2C_CON_REG); /* STP */
}
pr_exit:
flush_fifo(i2c_base, ip_rev);
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
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(void __iomem *i2c_base, int ip_rev, int waitdelay,
uchar chip, uint addr, int alen, uchar *buffer,
int len)
{
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;
}
#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
/*
* EEPROM chips that implement "address overflow" are ones
* like Catalyst 24WC04/08/16 which has 9/10/11 bits of
* address and the extra bits end up in the "chip address"
* bit slots. This makes a 24WC08 (1Kbyte) chip look like
* four 256 byte chips.
*
* Note that we consider the length of the address field to
* still be one byte because the extra address bits are
* hidden in the chip address.
*/
if (alen > 0)
chip |= ((addr >> (alen * 8)) &
CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
#endif
/* Wait until bus not busy */
if (wait_for_bb(i2c_base, ip_rev, waitdelay))
return 1;
/* Zero, one or two bytes reg address (offset) */
omap_i2c_write_reg(i2c_base, ip_rev, alen, OMAP_I2C_CNT_REG);
/* Set slave address */
omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
if (alen) {
/* Must write reg offset first */
#ifdef CONFIG_I2C_REPEATED_START
/* No stop bit, use Repeated Start (Sr) */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_STT | I2C_CON_TRX, OMAP_I2C_CON_REG);
#else
/* Stop - Start (P-S) */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_STT | I2C_CON_STP | I2C_CON_TRX,
OMAP_I2C_CON_REG);
#endif
/* Send register offset */
while (1) {
status = wait_for_event(i2c_base, ip_rev, waitdelay);
/* 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 probably not configured (status=0x%x)\n",
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) {
u8 addr_byte;
alen--;
addr_byte = (addr >> (8 * alen)) & 0xff;
omap_i2c_write_reg(i2c_base, ip_rev,
addr_byte,
OMAP_I2C_DATA_REG);
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_XRDY,
OMAP_I2C_STAT_REG);
}
}
if (status & I2C_STAT_ARDY) {
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_ARDY,
OMAP_I2C_STAT_REG);
break;
}
}
}
/* Set slave address */
omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
/* Read len bytes from slave */
omap_i2c_write_reg(i2c_base, ip_rev, len, OMAP_I2C_CNT_REG);
/* Need stop bit here */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_STT | I2C_CON_STP, OMAP_I2C_CON_REG);
/* Receive data */
while (1) {
status = wait_for_event(i2c_base, ip_rev, waitdelay);
/*
* 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 probably not configured (status=0x%x)\n",
status);
goto rd_exit;
}
if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
goto rd_exit;
}
if (status & I2C_STAT_RRDY) {
*buffer++ = omap_i2c_read_reg(i2c_base, ip_rev,
OMAP_I2C_DATA_REG);
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_RRDY, OMAP_I2C_STAT_REG);
}
if (status & I2C_STAT_ARDY) {
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_ARDY, OMAP_I2C_STAT_REG);
break;
}
}
rd_exit:
flush_fifo(i2c_base, ip_rev);
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
return i2c_error;
}
/* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
static int __omap24_i2c_write(void __iomem *i2c_base, int ip_rev, int waitdelay,
uchar chip, uint addr, int alen, uchar *buffer,
int len)
{
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;
}
#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
/*
* EEPROM chips that implement "address overflow" are ones
* like Catalyst 24WC04/08/16 which has 9/10/11 bits of
* address and the extra bits end up in the "chip address"
* bit slots. This makes a 24WC08 (1Kbyte) chip look like
* four 256 byte chips.
*
* Note that we consider the length of the address field to
* still be one byte because the extra address bits are
* hidden in the chip address.
*/
if (alen > 0)
chip |= ((addr >> (alen * 8)) &
CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
#endif
/* Wait until bus not busy */
if (wait_for_bb(i2c_base, ip_rev, waitdelay))
return 1;
/* Start address phase - will write regoffset + len bytes data */
omap_i2c_write_reg(i2c_base, ip_rev, alen + len, OMAP_I2C_CNT_REG);
/* Set slave address */
omap_i2c_write_reg(i2c_base, ip_rev, chip, OMAP_I2C_SA_REG);
/* Stop bit needed here */
omap_i2c_write_reg(i2c_base, ip_rev, I2C_CON_EN | I2C_CON_MST |
I2C_CON_STT | I2C_CON_TRX | I2C_CON_STP,
OMAP_I2C_CON_REG);
while (alen) {
/* Must write reg offset (one or two bytes) */
status = wait_for_event(i2c_base, ip_rev, waitdelay);
/* 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 probably not configured (status=0x%x)\n",
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--;
omap_i2c_write_reg(i2c_base, ip_rev,
(addr >> (8 * alen)) & 0xff,
OMAP_I2C_DATA_REG);
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_XRDY, OMAP_I2C_STAT_REG);
} 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(i2c_base, ip_rev, waitdelay);
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) {
omap_i2c_write_reg(i2c_base, ip_rev,
buffer[i], OMAP_I2C_DATA_REG);
omap_i2c_write_reg(i2c_base, ip_rev,
I2C_STAT_XRDY, OMAP_I2C_STAT_REG);
} 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(i2c_base, ip_rev, waitdelay);
} while (!(status & I2C_STAT_ARDY) && timeout--);
if (timeout <= 0)
printf("i2c_write: timed out writig last byte!\n");
wr_exit:
flush_fifo(i2c_base, ip_rev);
omap_i2c_write_reg(i2c_base, ip_rev, 0xFFFF, OMAP_I2C_STAT_REG);
return i2c_error;
}
#if !CONFIG_IS_ENABLED(DM_I2C)
/*
* The legacy I2C functions. These need to get removed once
* all users of this driver are converted to DM.
*/
static void __iomem *omap24_get_base(struct i2c_adapter *adap)
{
switch (adap->hwadapnr) {
case 0:
return (void __iomem *)I2C_BASE1;
break;
case 1:
return (void __iomem *)I2C_BASE2;
break;
#if (CONFIG_SYS_I2C_BUS_MAX > 2)
case 2:
return (void __iomem *)I2C_BASE3;
break;
#if (CONFIG_SYS_I2C_BUS_MAX > 3)
case 3:
return (void __iomem *)I2C_BASE4;
break;
#if (CONFIG_SYS_I2C_BUS_MAX > 4)
case 4:
return (void __iomem *)I2C_BASE5;
break;
#endif
#endif
#endif
default:
printf("wrong hwadapnr: %d\n", adap->hwadapnr);
break;
}
return NULL;
}
static int omap24_get_ip_rev(void)
{
#ifdef CONFIG_OMAP34XX
return OMAP_I2C_REV_V1;
#else
return OMAP_I2C_REV_V2;
#endif
}
static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
void __iomem *i2c_base = omap24_get_base(adap);
int ip_rev = omap24_get_ip_rev();
return __omap24_i2c_read(i2c_base, ip_rev, adap->waitdelay, chip, addr,
alen, buffer, len);
}
static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
void __iomem *i2c_base = omap24_get_base(adap);
int ip_rev = omap24_get_ip_rev();
return __omap24_i2c_write(i2c_base, ip_rev, adap->waitdelay, chip, addr,
alen, buffer, len);
}
static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
{
void __iomem *i2c_base = omap24_get_base(adap);
int ip_rev = omap24_get_ip_rev();
int ret;
ret = __omap24_i2c_setspeed(i2c_base, ip_rev, speed, &adap->waitdelay);
if (ret) {
pr_err("%s: set i2c speed failed\n", __func__);
return ret;
}
adap->speed = speed;
return 0;
}
static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
{
void __iomem *i2c_base = omap24_get_base(adap);
int ip_rev = omap24_get_ip_rev();
return __omap24_i2c_init(i2c_base, ip_rev, speed, slaveadd,
&adap->waitdelay);
}
static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
{
void __iomem *i2c_base = omap24_get_base(adap);
int ip_rev = omap24_get_ip_rev();
return __omap24_i2c_probe(i2c_base, ip_rev, adap->waitdelay, chip);
}
U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe,
omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
CONFIG_SYS_I2C_SPEED,
CONFIG_SYS_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_I2C_SPEED,
CONFIG_SYS_I2C_SLAVE,
1)
#if (CONFIG_SYS_I2C_BUS_MAX > 2)
U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe,
omap24_i2c_read, omap24_i2c_write, NULL,
CONFIG_SYS_I2C_SPEED,
CONFIG_SYS_I2C_SLAVE,
2)
#if (CONFIG_SYS_I2C_BUS_MAX > 3)
U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe,
omap24_i2c_read, omap24_i2c_write, NULL,
CONFIG_SYS_I2C_SPEED,
CONFIG_SYS_I2C_SLAVE,
3)
#if (CONFIG_SYS_I2C_BUS_MAX > 4)
U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe,
omap24_i2c_read, omap24_i2c_write, NULL,
CONFIG_SYS_I2C_SPEED,
CONFIG_SYS_I2C_SLAVE,
4)
#endif
#endif
#endif
#else /* CONFIG_DM_I2C */
static int omap_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
{
struct omap_i2c *priv = dev_get_priv(bus);
int ret;
debug("i2c_xfer: %d messages\n", nmsgs);
for (; nmsgs > 0; nmsgs--, msg++) {
debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
if (msg->flags & I2C_M_RD) {
ret = __omap24_i2c_read(priv->regs, priv->ip_rev,
priv->waitdelay,
msg->addr, 0, 0, msg->buf,
msg->len);
} else {
ret = __omap24_i2c_write(priv->regs, priv->ip_rev,
priv->waitdelay,
msg->addr, 0, 0, msg->buf,
msg->len);
}
if (ret) {
debug("i2c_write: error sending\n");
return -EREMOTEIO;
}
}
return 0;
}
static int omap_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
struct omap_i2c *priv = dev_get_priv(bus);
priv->speed = speed;
return __omap24_i2c_setspeed(priv->regs, priv->ip_rev, speed,
&priv->waitdelay);
}
static int omap_i2c_probe_chip(struct udevice *bus, uint chip_addr,
uint chip_flags)
{
struct omap_i2c *priv = dev_get_priv(bus);
return __omap24_i2c_probe(priv->regs, priv->ip_rev, priv->waitdelay,
chip_addr) ? -EREMOTEIO : 0;
}
static int omap_i2c_probe(struct udevice *bus)
{
struct omap_i2c *priv = dev_get_priv(bus);
struct omap_i2c_plat *plat = dev_get_plat(bus);
priv->speed = plat->speed;
priv->regs = map_physmem(plat->base, sizeof(void *),
MAP_NOCACHE);
priv->ip_rev = plat->ip_rev;
__omap24_i2c_init(priv->regs, priv->ip_rev, priv->speed, 0,
&priv->waitdelay);
return 0;
}
#if CONFIG_IS_ENABLED(OF_REAL)
static int omap_i2c_of_to_plat(struct udevice *bus)
{
struct omap_i2c_plat *plat = dev_get_plat(bus);
plat->base = dev_read_addr(bus);
plat->speed = dev_read_u32_default(bus, "clock-frequency",
I2C_SPEED_STANDARD_RATE);
plat->ip_rev = dev_get_driver_data(bus);
return 0;
}
static const struct udevice_id omap_i2c_ids[] = {
{ .compatible = "ti,omap3-i2c", .data = OMAP_I2C_REV_V1 },
{ .compatible = "ti,omap4-i2c", .data = OMAP_I2C_REV_V2 },
{ }
};
#endif
static const struct dm_i2c_ops omap_i2c_ops = {
.xfer = omap_i2c_xfer,
.probe_chip = omap_i2c_probe_chip,
.set_bus_speed = omap_i2c_set_bus_speed,
};
U_BOOT_DRIVER(i2c_omap) = {
.name = "i2c_omap",
.id = UCLASS_I2C,
#if CONFIG_IS_ENABLED(OF_REAL)
.of_match = omap_i2c_ids,
.of_to_plat = omap_i2c_of_to_plat,
.plat_auto = sizeof(struct omap_i2c_plat),
#endif
.probe = omap_i2c_probe,
.priv_auto = sizeof(struct omap_i2c),
.ops = &omap_i2c_ops,
#if !CONFIG_IS_ENABLED(OF_CONTROL)
.flags = DM_FLAG_PRE_RELOC,
#endif
};
#endif /* CONFIG_DM_I2C */
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