diff options
Diffstat (limited to 'drivers/i2c/s3c24x0_i2c.c')
| -rw-r--r-- | drivers/i2c/s3c24x0_i2c.c | 835 |
1 files changed, 670 insertions, 165 deletions
diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index cd09c788be..f77a9d1a1f 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -34,6 +34,76 @@ #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 */ @@ -43,19 +113,43 @@ #define I2C_START_STOP 0x20 /* START / STOP */ #define I2C_TXRX_ENA 0x10 /* I2C Tx/Rx enable */ -#define I2C_TIMEOUT 1 /* 1 second */ +#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"))); -#ifdef CONFIG_OF_CONTROL -static int i2c_busses __attribute__((section(".data"))); static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM] __attribute__((section(".data"))); -#endif + +/** + * 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) @@ -84,22 +178,75 @@ static void SetI2CSCL(int x) } #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) { - int i; + ulong start_time = get_timer(0); - i = I2C_TIMEOUT * 10000; - while (!(readl(&i2c->iiccon) & I2CCON_IRPND) && (i > 0)) { - udelay(100); - i--; - } + 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 (readl(&i2c->iiccon) & I2CCON_IRPND) ? I2C_OK : I2C_NOK_TOUT; + return I2C_NOK_TOUT; } -static int IsACK(struct s3c24x0_i2c *i2c) +/* + * 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) { - return !(readl(&i2c->iicstat) & I2CSTAT_NACK); + 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) @@ -151,6 +298,109 @@ static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd) 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 */ @@ -158,16 +408,21 @@ static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd) #ifdef CONFIG_I2C_MULTI_BUS int i2c_set_bus_num(unsigned int bus) { - struct s3c24x0_i2c *i2c; + struct s3c24x0_i2c_bus *i2c_bus; - if ((bus < 0) || (bus >= CONFIG_MAX_I2C_NUM)) { - debug("Bad bus: %d\n", bus); + i2c_bus = get_bus(bus); + if (!i2c_bus) return -1; - } - g_current_bus = bus; - i2c = get_base_i2c(); - i2c_ch_init(i2c, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); + + 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; } @@ -184,20 +439,27 @@ void i2c_init(int speed, int slaveadd) #if !(defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5) struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); #endif - int i; + ulong start_time = get_timer(0); /* By default i2c channel 0 is the current bus */ g_current_bus = 0; i2c = get_base_i2c(); - /* wait for some time to give previous transfer a chance to finish */ - i = I2C_TIMEOUT * 1000; - while ((readl(&i2c->iicstat) & I2CSTAT_BSY) && (i > 0)) { - udelay(1000); - i--; + /* + * 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); @@ -246,6 +508,227 @@ void i2c_init(int speed, int 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 @@ -260,7 +743,8 @@ static int i2c_transfer(struct s3c24x0_i2c *i2c, unsigned char data[], unsigned short data_len) { - int i, result; + 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 */ @@ -268,128 +752,78 @@ static int i2c_transfer(struct s3c24x0_i2c *i2c, return I2C_NOK; } - /* Check I2C bus idle */ - i = I2C_TIMEOUT * 1000; - while ((readl(&i2c->iicstat) & I2CSTAT_BSY) && (i > 0)) { - udelay(1000); - i--; + while (readl(&i2c->iicstat) & I2CSTAT_BSY) { + if (get_timer(start_time) > I2C_TIMEOUT_MS) + return I2C_NOK_TOUT; } - if (readl(&i2c->iicstat) & I2CSTAT_BSY) - return I2C_NOK_TOUT; - writel(readl(&i2c->iiccon) | I2CCON_ACKGEN, &i2c->iiccon); - result = I2C_OK; - switch (cmd_type) { - case I2C_WRITE: - if (addr && addr_len) { - writel(chip, &i2c->iicds); - /* send START */ - writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP, - &i2c->iicstat); - i = 0; - while ((i < addr_len) && (result == I2C_OK)) { - result = WaitForXfer(i2c); - writel(addr[i], &i2c->iicds); - ReadWriteByte(i2c); - i++; - } - i = 0; - while ((i < data_len) && (result == I2C_OK)) { - result = WaitForXfer(i2c); - writel(data[i], &i2c->iicds); - ReadWriteByte(i2c); - i++; - } - } else { - writel(chip, &i2c->iicds); - /* send START */ - writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP, - &i2c->iicstat); - i = 0; - while ((i < data_len) && (result == I2C_OK)) { - result = WaitForXfer(i2c); - writel(data[i], &i2c->iicds); - ReadWriteByte(i2c); - i++; - } + /* 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; + } - if (result == I2C_OK) + switch (cmd_type) { + case I2C_WRITE: + while ((i < data_len) && (result == I2C_OK)) { + writel(data[i++], &i2c->iicds); + ReadWriteByte(i2c); result = WaitForXfer(i2c); - - /* send STOP */ - writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat); - ReadWriteByte(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); - /* send START */ - writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP, - &i2c->iicstat); - result = WaitForXfer(i2c); - if (IsACK(i2c)) { - i = 0; - while ((i < addr_len) && (result == I2C_OK)) { - writel(addr[i], &i2c->iicds); - ReadWriteByte(i2c); - result = WaitForXfer(i2c); - i++; - } - - writel(chip, &i2c->iicds); - /* resend START */ - writel(I2C_MODE_MR | I2C_TXRX_ENA | - I2C_START_STOP, &i2c->iicstat); - ReadWriteByte(i2c); - result = WaitForXfer(i2c); - i = 0; - 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); - i++; - } - } else { - result = I2C_NACK; - } - } else { - writel(chip, &i2c->iicds); - /* send START */ + /* Generate a re-START. */ writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP, &i2c->iicstat); + ReadWriteByte(i2c); result = WaitForXfer(i2c); - if (IsACK(i2c)) { - i = 0; - 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); - i++; - } - } else { - result = I2C_NACK; - } + if (result != I2C_OK) + goto bailout; } - /* send STOP */ - writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat); - ReadWriteByte(i2c); + 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: @@ -398,15 +832,23 @@ static int i2c_transfer(struct s3c24x0_i2c *i2c, 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 *i2c; + struct s3c24x0_i2c_bus *i2c_bus; uchar buf[1]; + int ret; - i2c = get_base_i2c(); + i2c_bus = get_bus(g_current_bus); + if (!i2c_bus) + return -1; buf[0] = 0; /* @@ -414,12 +856,21 @@ int i2c_probe(uchar chip) * address was <ACK>ed (i.e. there was a chip at that address which * drove the data line low). */ - return i2c_transfer(i2c, I2C_READ, chip << 1, 0, 0, buf, 1) != I2C_OK; + 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 *i2c; + struct s3c24x0_i2c_bus *i2c_bus; uchar xaddr[4]; int ret; @@ -451,11 +902,21 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); #endif - i2c = get_base_i2c(); - ret = i2c_transfer(i2c, I2C_READ, chip << 1, &xaddr[4 - alen], alen, - buffer, len); - if (ret != 0) { - debug("I2c read: failed %d\n", ret); + 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; @@ -463,8 +924,9 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) { - struct s3c24x0_i2c *i2c; + struct s3c24x0_i2c_bus *i2c_bus; uchar xaddr[4]; + int ret; if (alen > 4) { debug("I2C write: addr len %d not supported\n", alen); @@ -493,53 +955,87 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); #endif - i2c = get_base_i2c(); - return (i2c_transfer - (i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, - len) != 0); + 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 -void board_i2c_init(const void *blob) +static void process_nodes(const void *blob, int node_list[], int count, + int is_highspeed) { + struct s3c24x0_i2c_bus *bus; int i; - int node_list[CONFIG_MAX_I2C_NUM]; - int count; - - count = fdtdec_find_aliases_for_id(blob, "i2c", - COMPAT_SAMSUNG_S3C2440_I2C, node_list, - CONFIG_MAX_I2C_NUM); for (i = 0; i < count; i++) { - struct s3c24x0_i2c_bus *bus; int node = node_list[i]; if (node <= 0) continue; + bus = &i2c_bus[i]; - bus->regs = (struct s3c24x0_i2c *) - fdtdec_get_addr(blob, node, "reg"); + 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 = i2c_busses++; + bus->bus_num = i; exynos_pinmux_config(bus->id, 0); + + /* Mark position as used */ + node_list[i] = -1; } } -static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx) +void board_i2c_init(const void *blob) { - if (bus_idx < i2c_busses) - return &i2c_bus[bus_idx]; + 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); - debug("Undefined bus: %d\n", bus_idx); - return NULL; } int i2c_get_bus_num_fdt(int node) { int i; - for (i = 0; i < i2c_busses; i++) { + for (i = 0; i < ARRAY_SIZE(i2c_bus); i++) { if (node == i2c_bus[i].node) return i; } @@ -548,9 +1044,10 @@ int i2c_get_bus_num_fdt(int node) return -1; } +#ifdef CONFIG_I2C_MULTI_BUS int i2c_reset_port_fdt(const void *blob, int node) { - struct s3c24x0_i2c_bus *i2c; + struct s3c24x0_i2c_bus *i2c_bus; int bus; bus = i2c_get_bus_num_fdt(node); @@ -559,16 +1056,24 @@ int i2c_reset_port_fdt(const void *blob, int node) return -1; } - i2c = get_bus(bus); - if (!i2c) { + i2c_bus = get_bus(bus); + if (!i2c_bus) { debug("get_bus() failed for node node %d\n", node); return -1; } - i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); + 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 */ |
