/* * (C) Copyright 2002 * David Mueller, ELSOFT AG, d.mueller@elsoft.ch * * SPDX-License-Identifier: GPL-2.0+ */ /* This code should work for both the S3C2400 and the S3C2410 * as they seem to have the same I2C controller inside. * The different address mapping is handled by the s3c24xx.h files below. */ #include #include #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) #include #include #include #else #include #endif #include #include #include "s3c24x0_i2c.h" #ifdef CONFIG_HARD_I2C #define I2C_WRITE 0 #define I2C_READ 1 #define I2C_OK 0 #define I2C_NOK 1 #define I2C_NACK 2 #define I2C_NOK_LA 3 /* Lost arbitration */ #define I2C_NOK_TOUT 4 /* time out */ /* HSI2C specific register description */ /* I2C_CTL Register bits */ #define HSI2C_FUNC_MODE_I2C (1u << 0) #define HSI2C_MASTER (1u << 3) #define HSI2C_RXCHON (1u << 6) /* Write/Send */ #define HSI2C_TXCHON (1u << 7) /* Read/Receive */ #define HSI2C_SW_RST (1u << 31) /* I2C_FIFO_CTL Register bits */ #define HSI2C_RXFIFO_EN (1u << 0) #define HSI2C_TXFIFO_EN (1u << 1) #define HSI2C_TXFIFO_TRIGGER_LEVEL (0x20 << 16) #define HSI2C_RXFIFO_TRIGGER_LEVEL (0x20 << 4) /* I2C_TRAILING_CTL Register bits */ #define HSI2C_TRAILING_COUNT (0xff) /* I2C_INT_EN Register bits */ #define HSI2C_TX_UNDERRUN_EN (1u << 2) #define HSI2C_TX_OVERRUN_EN (1u << 3) #define HSI2C_RX_UNDERRUN_EN (1u << 4) #define HSI2C_RX_OVERRUN_EN (1u << 5) #define HSI2C_INT_TRAILING_EN (1u << 6) #define HSI2C_INT_I2C_EN (1u << 9) #define HSI2C_INT_ERROR_MASK (HSI2C_TX_UNDERRUN_EN |\ HSI2C_TX_OVERRUN_EN |\ HSI2C_RX_UNDERRUN_EN |\ HSI2C_RX_OVERRUN_EN |\ HSI2C_INT_TRAILING_EN) /* I2C_CONF Register bits */ #define HSI2C_AUTO_MODE (1u << 31) #define HSI2C_10BIT_ADDR_MODE (1u << 30) #define HSI2C_HS_MODE (1u << 29) /* I2C_AUTO_CONF Register bits */ #define HSI2C_READ_WRITE (1u << 16) #define HSI2C_STOP_AFTER_TRANS (1u << 17) #define HSI2C_MASTER_RUN (1u << 31) /* I2C_TIMEOUT Register bits */ #define HSI2C_TIMEOUT_EN (1u << 31) /* I2C_TRANS_STATUS register bits */ #define HSI2C_MASTER_BUSY (1u << 17) #define HSI2C_SLAVE_BUSY (1u << 16) #define HSI2C_TIMEOUT_AUTO (1u << 4) #define HSI2C_NO_DEV (1u << 3) #define HSI2C_NO_DEV_ACK (1u << 2) #define HSI2C_TRANS_ABORT (1u << 1) #define HSI2C_TRANS_SUCCESS (1u << 0) #define HSI2C_TRANS_ERROR_MASK (HSI2C_TIMEOUT_AUTO |\ HSI2C_NO_DEV | HSI2C_NO_DEV_ACK |\ HSI2C_TRANS_ABORT) #define HSI2C_TRANS_FINISHED_MASK (HSI2C_TRANS_ERROR_MASK | HSI2C_TRANS_SUCCESS) /* I2C_FIFO_STAT Register bits */ #define HSI2C_RX_FIFO_EMPTY (1u << 24) #define HSI2C_RX_FIFO_FULL (1u << 23) #define HSI2C_TX_FIFO_EMPTY (1u << 8) #define HSI2C_TX_FIFO_FULL (1u << 7) #define HSI2C_RX_FIFO_LEVEL(x) (((x) >> 16) & 0x7f) #define HSI2C_TX_FIFO_LEVEL(x) ((x) & 0x7f) #define HSI2C_SLV_ADDR_MAS(x) ((x & 0x3ff) << 10) /* S3C I2C Controller bits */ #define I2CSTAT_BSY 0x20 /* Busy bit */ #define I2CSTAT_NACK 0x01 /* Nack bit */ #define I2CCON_ACKGEN 0x80 /* Acknowledge generation */ #define I2CCON_IRPND 0x10 /* Interrupt pending bit */ #define I2C_MODE_MT 0xC0 /* Master Transmit Mode */ #define I2C_MODE_MR 0x80 /* Master Receive Mode */ #define I2C_START_STOP 0x20 /* START / STOP */ #define I2C_TXRX_ENA 0x10 /* I2C Tx/Rx enable */ #define I2C_TIMEOUT_MS 1000 /* 1 second */ #define HSI2C_TIMEOUT_US 100000 /* 100 ms, finer granularity */ /* To support VCMA9 boards and other who dont define max_i2c_num */ #ifndef CONFIG_MAX_I2C_NUM #define CONFIG_MAX_I2C_NUM 1 #endif /* * For SPL boot some boards need i2c before SDRAM is initialised so force * variables to live in SRAM */ static unsigned int g_current_bus __attribute__((section(".data"))); static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM] __attribute__((section(".data"))); /** * Get a pointer to the given bus index * * @bus_idx: Bus index to look up * @return pointer to bus, or NULL if invalid or not available */ static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx) { if (bus_idx < ARRAY_SIZE(i2c_bus)) { struct s3c24x0_i2c_bus *bus; bus = &i2c_bus[bus_idx]; if (bus->active) return bus; } debug("Undefined bus: %d\n", bus_idx); return NULL; } #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) static int GetI2CSDA(void) { struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); #ifdef CONFIG_S3C2410 return (readl(&gpio->gpedat) & 0x8000) >> 15; #endif #ifdef CONFIG_S3C2400 return (readl(&gpio->pgdat) & 0x0020) >> 5; #endif } static void SetI2CSCL(int x) { struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); #ifdef CONFIG_S3C2410 writel((readl(&gpio->gpedat) & ~0x4000) | (x & 1) << 14, &gpio->gpedat); #endif #ifdef CONFIG_S3C2400 writel((readl(&gpio->pgdat) & ~0x0040) | (x & 1) << 6, &gpio->pgdat); #endif } #endif /* * Wait til the byte transfer is completed. * * @param i2c- pointer to the appropriate i2c register bank. * @return I2C_OK, if transmission was ACKED * I2C_NACK, if transmission was NACKED * I2C_NOK_TIMEOUT, if transaction did not complete in I2C_TIMEOUT_MS */ static int WaitForXfer(struct s3c24x0_i2c *i2c) { ulong start_time = get_timer(0); do { if (readl(&i2c->iiccon) & I2CCON_IRPND) return (readl(&i2c->iicstat) & I2CSTAT_NACK) ? I2C_NACK : I2C_OK; } while (get_timer(start_time) < I2C_TIMEOUT_MS); return I2C_NOK_TOUT; } /* * Wait for transfer completion. * * This function reads the interrupt status register waiting for the INT_I2C * bit to be set, which indicates copletion of a transaction. * * @param i2c: pointer to the appropriate register bank * * @return: I2C_OK in case of successful completion, I2C_NOK_TIMEOUT in case * the status bits do not get set in time, or an approrpiate error * value in case of transfer errors. */ static int hsi2c_wait_for_trx(struct exynos5_hsi2c *i2c) { int i = HSI2C_TIMEOUT_US; while (i-- > 0) { u32 int_status = readl(&i2c->usi_int_stat); if (int_status & HSI2C_INT_I2C_EN) { u32 trans_status = readl(&i2c->usi_trans_status); /* Deassert pending interrupt. */ writel(int_status, &i2c->usi_int_stat); if (trans_status & HSI2C_NO_DEV_ACK) { debug("%s: no ACK from device\n", __func__); return I2C_NACK; } if (trans_status & HSI2C_NO_DEV) { debug("%s: no device\n", __func__); return I2C_NOK; } if (trans_status & HSI2C_TRANS_ABORT) { debug("%s: arbitration lost\n", __func__); return I2C_NOK_LA; } if (trans_status & HSI2C_TIMEOUT_AUTO) { debug("%s: device timed out\n", __func__); return I2C_NOK_TOUT; } return I2C_OK; } udelay(1); } debug("%s: transaction timeout!\n", __func__); return I2C_NOK_TOUT; } static void ReadWriteByte(struct s3c24x0_i2c *i2c) { writel(readl(&i2c->iiccon) & ~I2CCON_IRPND, &i2c->iiccon); } static struct s3c24x0_i2c *get_base_i2c(void) { #ifdef CONFIG_EXYNOS4 struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c() + (EXYNOS4_I2C_SPACING * g_current_bus)); return i2c; #elif defined CONFIG_EXYNOS5 struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c() + (EXYNOS5_I2C_SPACING * g_current_bus)); return i2c; #else return s3c24x0_get_base_i2c(); #endif } static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd) { ulong freq, pres = 16, div; #if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) freq = get_i2c_clk(); #else freq = get_PCLK(); #endif /* calculate prescaler and divisor values */ if ((freq / pres / (16 + 1)) > speed) /* set prescaler to 512 */ pres = 512; div = 0; while ((freq / pres / (div + 1)) > speed) div++; /* set prescaler, divisor according to freq, also set ACKGEN, IRQ */ writel((div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0), &i2c->iiccon); /* init to SLAVE REVEIVE and set slaveaddr */ writel(0, &i2c->iicstat); writel(slaveadd, &i2c->iicadd); /* program Master Transmit (and implicit STOP) */ writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat); } #ifdef CONFIG_I2C_MULTI_BUS static int hsi2c_get_clk_details(struct s3c24x0_i2c_bus *i2c_bus) { struct exynos5_hsi2c *hsregs = i2c_bus->hsregs; ulong clkin; unsigned int op_clk = i2c_bus->clock_frequency; unsigned int i = 0, utemp0 = 0, utemp1 = 0; unsigned int t_ftl_cycle; #if defined CONFIG_EXYNOS5 clkin = get_i2c_clk(); #endif /* FPCLK / FI2C = * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE * uTemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) * uTemp1 = (TSCLK_L + TSCLK_H + 2) * uTemp2 = TSCLK_L + TSCLK_H */ t_ftl_cycle = (readl(&hsregs->usi_conf) >> 16) & 0x7; utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle; /* CLK_DIV max is 256 */ for (i = 0; i < 256; i++) { utemp1 = utemp0 / (i + 1); if ((utemp1 < 512) && (utemp1 > 4)) { i2c_bus->clk_cycle = utemp1 - 2; i2c_bus->clk_div = i; return 0; } } return -1; } #endif static void hsi2c_ch_init(struct s3c24x0_i2c_bus *i2c_bus) { struct exynos5_hsi2c *hsregs = i2c_bus->hsregs; unsigned int t_sr_release; unsigned int n_clkdiv; unsigned int t_start_su, t_start_hd; unsigned int t_stop_su; unsigned int t_data_su, t_data_hd; unsigned int t_scl_l, t_scl_h; u32 i2c_timing_s1; u32 i2c_timing_s2; u32 i2c_timing_s3; u32 i2c_timing_sla; n_clkdiv = i2c_bus->clk_div; t_scl_l = i2c_bus->clk_cycle / 2; t_scl_h = i2c_bus->clk_cycle / 2; t_start_su = t_scl_l; t_start_hd = t_scl_l; t_stop_su = t_scl_l; t_data_su = t_scl_l / 2; t_data_hd = t_scl_l / 2; t_sr_release = i2c_bus->clk_cycle; i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8; i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0; i2c_timing_s3 = n_clkdiv << 16 | t_sr_release << 0; i2c_timing_sla = t_data_hd << 0; writel(HSI2C_TRAILING_COUNT, &hsregs->usi_trailing_ctl); /* Clear to enable Timeout */ clrsetbits_le32(&hsregs->usi_timeout, HSI2C_TIMEOUT_EN, 0); /* set AUTO mode */ writel(readl(&hsregs->usi_conf) | HSI2C_AUTO_MODE, &hsregs->usi_conf); /* Enable completion conditions' reporting. */ writel(HSI2C_INT_I2C_EN, &hsregs->usi_int_en); /* Enable FIFOs */ writel(HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN, &hsregs->usi_fifo_ctl); /* Currently operating in Fast speed mode. */ writel(i2c_timing_s1, &hsregs->usi_timing_fs1); writel(i2c_timing_s2, &hsregs->usi_timing_fs2); writel(i2c_timing_s3, &hsregs->usi_timing_fs3); writel(i2c_timing_sla, &hsregs->usi_timing_sla); } /* SW reset for the high speed bus */ static void exynos5_i2c_reset(struct s3c24x0_i2c_bus *i2c_bus) { struct exynos5_hsi2c *i2c = i2c_bus->hsregs; u32 i2c_ctl; /* Set and clear the bit for reset */ i2c_ctl = readl(&i2c->usi_ctl); i2c_ctl |= HSI2C_SW_RST; writel(i2c_ctl, &i2c->usi_ctl); i2c_ctl = readl(&i2c->usi_ctl); i2c_ctl &= ~HSI2C_SW_RST; writel(i2c_ctl, &i2c->usi_ctl); /* Initialize the configure registers */ hsi2c_ch_init(i2c_bus); } /* * MULTI BUS I2C support */ #ifdef CONFIG_I2C_MULTI_BUS int i2c_set_bus_num(unsigned int bus) { struct s3c24x0_i2c_bus *i2c_bus; i2c_bus = get_bus(bus); if (!i2c_bus) return -1; g_current_bus = bus; if (i2c_bus->is_highspeed) { if (hsi2c_get_clk_details(i2c_bus)) return -1; hsi2c_ch_init(i2c_bus); } else { i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency, CONFIG_SYS_I2C_SLAVE); } return 0; } unsigned int i2c_get_bus_num(void) { return g_current_bus; } #endif void i2c_init(int speed, int slaveadd) { struct s3c24x0_i2c *i2c; #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); #endif ulong start_time = get_timer(0); /* By default i2c channel 0 is the current bus */ g_current_bus = 0; i2c = get_base_i2c(); /* * In case the previous transfer is still going, wait to give it a * chance to finish. */ while (readl(&i2c->iicstat) & I2CSTAT_BSY) { if (get_timer(start_time) > I2C_TIMEOUT_MS) { printf("%s: I2C bus busy for %p\n", __func__, &i2c->iicstat); return; } } #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) int i; if ((readl(&i2c->iicstat) & I2CSTAT_BSY) || GetI2CSDA() == 0) { #ifdef CONFIG_S3C2410 ulong old_gpecon = readl(&gpio->gpecon); #endif #ifdef CONFIG_S3C2400 ulong old_gpecon = readl(&gpio->pgcon); #endif /* bus still busy probably by (most) previously interrupted transfer */ #ifdef CONFIG_S3C2410 /* set I2CSDA and I2CSCL (GPE15, GPE14) to GPIO */ writel((readl(&gpio->gpecon) & ~0xF0000000) | 0x10000000, &gpio->gpecon); #endif #ifdef CONFIG_S3C2400 /* set I2CSDA and I2CSCL (PG5, PG6) to GPIO */ writel((readl(&gpio->pgcon) & ~0x00003c00) | 0x00001000, &gpio->pgcon); #endif /* toggle I2CSCL until bus idle */ SetI2CSCL(0); udelay(1000); i = 10; while ((i > 0) && (GetI2CSDA() != 1)) { SetI2CSCL(1); udelay(1000); SetI2CSCL(0); udelay(1000); i--; } SetI2CSCL(1); udelay(1000); /* restore pin functions */ #ifdef CONFIG_S3C2410 writel(old_gpecon, &gpio->gpecon); #endif #ifdef CONFIG_S3C2400 writel(old_gpecon, &gpio->pgcon); #endif } #endif /* #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) */ i2c_ch_init(i2c, speed, slaveadd); } /* * Poll the appropriate bit of the fifo status register until the interface is * ready to process the next byte or timeout expires. * * In addition to the FIFO status register this function also polls the * interrupt status register to be able to detect unexpected transaction * completion. * * When FIFO is ready to process the next byte, this function returns I2C_OK. * If in course of polling the INT_I2C assertion is detected, the function * returns I2C_NOK. If timeout happens before any of the above conditions is * met - the function returns I2C_NOK_TOUT; * @param i2c: pointer to the appropriate i2c register bank. * @param rx_transfer: set to True if the receive transaction is in progress. * @return: as described above. */ static unsigned hsi2c_poll_fifo(struct exynos5_hsi2c *i2c, bool rx_transfer) { u32 fifo_bit = rx_transfer ? HSI2C_RX_FIFO_EMPTY : HSI2C_TX_FIFO_FULL; int i = HSI2C_TIMEOUT_US; while (readl(&i2c->usi_fifo_stat) & fifo_bit) { if (readl(&i2c->usi_int_stat) & HSI2C_INT_I2C_EN) { /* * There is a chance that assertion of * HSI2C_INT_I2C_EN and deassertion of * HSI2C_RX_FIFO_EMPTY happen simultaneously. Let's * give FIFO status priority and check it one more * time before reporting interrupt. The interrupt will * be reported next time this function is called. */ if (rx_transfer && !(readl(&i2c->usi_fifo_stat) & fifo_bit)) break; return I2C_NOK; } if (!i--) { debug("%s: FIFO polling timeout!\n", __func__); return I2C_NOK_TOUT; } udelay(1); } return I2C_OK; } /* * Preapre hsi2c transaction, either read or write. * * Set up transfer as described in section 27.5.1.2 'I2C Channel Auto Mode' of * the 5420 UM. * * @param i2c: pointer to the appropriate i2c register bank. * @param chip: slave address on the i2c bus (with read/write bit exlcuded) * @param len: number of bytes expected to be sent or received * @param rx_transfer: set to true for receive transactions * @param: issue_stop: set to true if i2c stop condition should be generated * after this transaction. * @return: I2C_NOK_TOUT in case the bus remained busy for HSI2C_TIMEOUT_US, * I2C_OK otherwise. */ static int hsi2c_prepare_transaction(struct exynos5_hsi2c *i2c, u8 chip, u16 len, bool rx_transfer, bool issue_stop) { u32 conf; conf = len | HSI2C_MASTER_RUN; if (issue_stop) conf |= HSI2C_STOP_AFTER_TRANS; /* Clear to enable Timeout */ writel(readl(&i2c->usi_timeout) & ~HSI2C_TIMEOUT_EN, &i2c->usi_timeout); /* Set slave address */ writel(HSI2C_SLV_ADDR_MAS(chip), &i2c->i2c_addr); if (rx_transfer) { /* i2c master, read transaction */ writel((HSI2C_RXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER), &i2c->usi_ctl); /* read up to len bytes, stop after transaction is finished */ writel(conf | HSI2C_READ_WRITE, &i2c->usi_auto_conf); } else { /* i2c master, write transaction */ writel((HSI2C_TXCHON | HSI2C_FUNC_MODE_I2C | HSI2C_MASTER), &i2c->usi_ctl); /* write up to len bytes, stop after transaction is finished */ writel(conf, &i2c->usi_auto_conf); } /* Reset all pending interrupt status bits we care about, if any */ writel(HSI2C_INT_I2C_EN, &i2c->usi_int_stat); return I2C_OK; } /* * Wait while i2c bus is settling down (mostly stop gets completed). */ static int hsi2c_wait_while_busy(struct exynos5_hsi2c *i2c) { int i = HSI2C_TIMEOUT_US; while (readl(&i2c->usi_trans_status) & HSI2C_MASTER_BUSY) { if (!i--) { debug("%s: bus busy\n", __func__); return I2C_NOK_TOUT; } udelay(1); } return I2C_OK; } static int hsi2c_write(struct exynos5_hsi2c *i2c, unsigned char chip, unsigned char addr[], unsigned char alen, unsigned char data[], unsigned short len, bool issue_stop) { int i, rv = 0; if (!(len + alen)) { /* Writes of zero length not supported in auto mode. */ debug("%s: zero length writes not supported\n", __func__); return I2C_NOK; } rv = hsi2c_prepare_transaction (i2c, chip, len + alen, false, issue_stop); if (rv != I2C_OK) return rv; /* Move address, if any, and the data, if any, into the FIFO. */ for (i = 0; i < alen; i++) { rv = hsi2c_poll_fifo(i2c, false); if (rv != I2C_OK) { debug("%s: address write failed\n", __func__); goto write_error; } writel(addr[i], &i2c->usi_txdata); } for (i = 0; i < len; i++) { rv = hsi2c_poll_fifo(i2c, false); if (rv != I2C_OK) { debug("%s: data write failed\n", __func__); goto write_error; } writel(data[i], &i2c->usi_txdata); } rv = hsi2c_wait_for_trx(i2c); write_error: if (issue_stop) { int tmp_ret = hsi2c_wait_while_busy(i2c); if (rv == I2C_OK) rv = tmp_ret; } writel(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl); /* done */ return rv; } static int hsi2c_read(struct exynos5_hsi2c *i2c, unsigned char chip, unsigned char addr[], unsigned char alen, unsigned char data[], unsigned short len) { int i, rv, tmp_ret; bool drop_data = false; if (!len) { /* Reads of zero length not supported in auto mode. */ debug("%s: zero length read adjusted\n", __func__); drop_data = true; len = 1; } if (alen) { /* Internal register adress needs to be written first. */ rv = hsi2c_write(i2c, chip, addr, alen, NULL, 0, false); if (rv != I2C_OK) return rv; } rv = hsi2c_prepare_transaction(i2c, chip, len, true, true); if (rv != I2C_OK) return rv; for (i = 0; i < len; i++) { rv = hsi2c_poll_fifo(i2c, true); if (rv != I2C_OK) goto read_err; if (drop_data) continue; data[i] = readl(&i2c->usi_rxdata); } rv = hsi2c_wait_for_trx(i2c); read_err: tmp_ret = hsi2c_wait_while_busy(i2c); if (rv == I2C_OK) rv = tmp_ret; writel(HSI2C_FUNC_MODE_I2C, &i2c->usi_ctl); /* done */ return rv; } /* * cmd_type is 0 for write, 1 for read. * * addr_len can take any value from 0-255, it is only limited * by the char, we could make it larger if needed. If it is * 0 we skip the address write cycle. */ static int i2c_transfer(struct s3c24x0_i2c *i2c, unsigned char cmd_type, unsigned char chip, unsigned char addr[], unsigned char addr_len, unsigned char data[], unsigned short data_len) { int i = 0, result; ulong start_time = get_timer(0); if (data == 0 || data_len == 0) { /*Don't support data transfer of no length or to address 0 */ debug("i2c_transfer: bad call\n"); return I2C_NOK; } while (readl(&i2c->iicstat) & I2CSTAT_BSY) { if (get_timer(start_time) > I2C_TIMEOUT_MS) return I2C_NOK_TOUT; } writel(readl(&i2c->iiccon) | I2CCON_ACKGEN, &i2c->iiccon); /* Get the slave chip address going */ writel(chip, &i2c->iicds); if ((cmd_type == I2C_WRITE) || (addr && addr_len)) writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP, &i2c->iicstat); else writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP, &i2c->iicstat); /* Wait for chip address to transmit. */ result = WaitForXfer(i2c); if (result != I2C_OK) goto bailout; /* If register address needs to be transmitted - do it now. */ if (addr && addr_len) { while ((i < addr_len) && (result == I2C_OK)) { writel(addr[i++], &i2c->iicds); ReadWriteByte(i2c); result = WaitForXfer(i2c); } i = 0; if (result != I2C_OK) goto bailout; } switch (cmd_type) { case I2C_WRITE: while ((i < data_len) && (result == I2C_OK)) { writel(data[i++], &i2c->iicds); ReadWriteByte(i2c); result = WaitForXfer(i2c); } break; case I2C_READ: if (addr && addr_len) { /* * Register address has been sent, now send slave chip * address again to start the actual read transaction. */ writel(chip, &i2c->iicds); /* Generate a re-START. */ writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP, &i2c->iicstat); ReadWriteByte(i2c); result = WaitForXfer(i2c); if (result != I2C_OK) goto bailout; } while ((i < data_len) && (result == I2C_OK)) { /* disable ACK for final READ */ if (i == data_len - 1) writel(readl(&i2c->iiccon) & ~I2CCON_ACKGEN, &i2c->iiccon); ReadWriteByte(i2c); result = WaitForXfer(i2c); data[i++] = readl(&i2c->iicds); } if (result == I2C_NACK) result = I2C_OK; /* Normal terminated read. */ break; default: debug("i2c_transfer: bad call\n"); result = I2C_NOK; break; } bailout: /* Send STOP. */ writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat); ReadWriteByte(i2c); return result; } int i2c_probe(uchar chip) { struct s3c24x0_i2c_bus *i2c_bus; uchar buf[1]; int ret; i2c_bus = get_bus(g_current_bus); if (!i2c_bus) return -1; buf[0] = 0; /* * What is needed is to send the chip address and verify that the * address was ed (i.e. there was a chip at that address which * drove the data line low). */ if (i2c_bus->is_highspeed) { ret = hsi2c_read(i2c_bus->hsregs, chip, 0, 0, buf, 1); } else { ret = i2c_transfer(i2c_bus->regs, I2C_READ, chip << 1, 0, 0, buf, 1); } return ret != I2C_OK; } int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) { struct s3c24x0_i2c_bus *i2c_bus; uchar xaddr[4]; int ret; if (alen > 4) { debug("I2C read: addr len %d not supported\n", alen); return 1; } if (alen > 0) { xaddr[0] = (addr >> 24) & 0xFF; xaddr[1] = (addr >> 16) & 0xFF; xaddr[2] = (addr >> 8) & 0xFF; xaddr[3] = addr & 0xFF; } #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 i2c_bus = get_bus(g_current_bus); if (!i2c_bus) return -1; if (i2c_bus->is_highspeed) ret = hsi2c_read(i2c_bus->hsregs, chip, &xaddr[4 - alen], alen, buffer, len); else ret = i2c_transfer(i2c_bus->regs, I2C_READ, chip << 1, &xaddr[4 - alen], alen, buffer, len); if (ret) { if (i2c_bus->is_highspeed) exynos5_i2c_reset(i2c_bus); debug("I2c read failed %d\n", ret); return 1; } return 0; } int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) { struct s3c24x0_i2c_bus *i2c_bus; uchar xaddr[4]; int ret; if (alen > 4) { debug("I2C write: addr len %d not supported\n", alen); return 1; } if (alen > 0) { xaddr[0] = (addr >> 24) & 0xFF; xaddr[1] = (addr >> 16) & 0xFF; xaddr[2] = (addr >> 8) & 0xFF; xaddr[3] = addr & 0xFF; } #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 i2c_bus = get_bus(g_current_bus); if (!i2c_bus) return -1; if (i2c_bus->is_highspeed) ret = hsi2c_write(i2c_bus->hsregs, chip, &xaddr[4 - alen], alen, buffer, len, true); else ret = i2c_transfer(i2c_bus->regs, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, len); if (ret != 0) { if (i2c_bus->is_highspeed) exynos5_i2c_reset(i2c_bus); return 1; } else { return 0; } } #ifdef CONFIG_OF_CONTROL static void process_nodes(const void *blob, int node_list[], int count, int is_highspeed) { struct s3c24x0_i2c_bus *bus; int i; for (i = 0; i < count; i++) { int node = node_list[i]; if (node <= 0) continue; bus = &i2c_bus[i]; bus->active = true; bus->is_highspeed = is_highspeed; if (is_highspeed) bus->hsregs = (struct exynos5_hsi2c *) fdtdec_get_addr(blob, node, "reg"); else bus->regs = (struct s3c24x0_i2c *) fdtdec_get_addr(blob, node, "reg"); bus->id = pinmux_decode_periph_id(blob, node); bus->clock_frequency = fdtdec_get_int(blob, node, "clock-frequency", CONFIG_SYS_I2C_SPEED); bus->node = node; bus->bus_num = i; exynos_pinmux_config(bus->id, 0); /* Mark position as used */ node_list[i] = -1; } } void board_i2c_init(const void *blob) { int node_list[CONFIG_MAX_I2C_NUM]; int count; /* First get the normal i2c ports */ count = fdtdec_find_aliases_for_id(blob, "i2c", COMPAT_SAMSUNG_S3C2440_I2C, node_list, CONFIG_MAX_I2C_NUM); process_nodes(blob, node_list, count, 0); /* Now look for high speed i2c ports */ count = fdtdec_find_aliases_for_id(blob, "i2c", COMPAT_SAMSUNG_EXYNOS5_I2C, node_list, CONFIG_MAX_I2C_NUM); process_nodes(blob, node_list, count, 1); } int i2c_get_bus_num_fdt(int node) { int i; for (i = 0; i < ARRAY_SIZE(i2c_bus); i++) { if (node == i2c_bus[i].node) return i; } debug("%s: Can't find any matched I2C bus\n", __func__); return -1; } #ifdef CONFIG_I2C_MULTI_BUS int i2c_reset_port_fdt(const void *blob, int node) { struct s3c24x0_i2c_bus *i2c_bus; int bus; bus = i2c_get_bus_num_fdt(node); if (bus < 0) { debug("could not get bus for node %d\n", node); return -1; } i2c_bus = get_bus(bus); if (!i2c_bus) { debug("get_bus() failed for node node %d\n", node); return -1; } if (i2c_bus->is_highspeed) { if (hsi2c_get_clk_details(i2c_bus)) return -1; hsi2c_ch_init(i2c_bus); } else { i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency, CONFIG_SYS_I2C_SLAVE); } return 0; } #endif #endif #endif /* CONFIG_HARD_I2C */