From 37b8eb37f8950538425d9956b65e8911a986002b Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Wed, 23 Nov 2016 06:34:43 -0700 Subject: [PATCH] samsung: i2c: Split the high-speed I2C code into a new driver Now that driver model is used for I2C on all boards, we can split the high-speed code into its own driver. There is virtually no common code, and this significantly reduces confusion. Signed-off-by: Simon Glass Acked-by: Heiko Schocher --- drivers/i2c/Makefile | 2 +- drivers/i2c/exynos_hs_i2c.c | 561 ++++++++++++++++++++++++++++++++++++++++++++ drivers/i2c/s3c24x0_i2c.c | 551 +------------------------------------------ drivers/i2c/s3c24x0_i2c.h | 22 ++ 4 files changed, 591 insertions(+), 545 deletions(-) create mode 100644 drivers/i2c/exynos_hs_i2c.c diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index 2987081..7c86198 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -34,7 +34,7 @@ obj-$(CONFIG_SYS_I2C_OMAP34XX) += omap24xx_i2c.o obj-$(CONFIG_SYS_I2C_PPC4XX) += ppc4xx_i2c.o obj-$(CONFIG_SYS_I2C_RCAR) += rcar_i2c.o obj-$(CONFIG_SYS_I2C_ROCKCHIP) += rk_i2c.o -obj-$(CONFIG_SYS_I2C_S3C24X0) += s3c24x0_i2c.o +obj-$(CONFIG_SYS_I2C_S3C24X0) += s3c24x0_i2c.o exynos_hs_i2c.o obj-$(CONFIG_SYS_I2C_SANDBOX) += sandbox_i2c.o i2c-emul-uclass.o obj-$(CONFIG_SYS_I2C_SH) += sh_i2c.o obj-$(CONFIG_SYS_I2C_SOFT) += soft_i2c.o diff --git a/drivers/i2c/exynos_hs_i2c.c b/drivers/i2c/exynos_hs_i2c.c new file mode 100644 index 0000000..9521aeb --- /dev/null +++ b/drivers/i2c/exynos_hs_i2c.c @@ -0,0 +1,561 @@ +/* + * Copyright (c) 2016, Google Inc + * + * (C) Copyright 2002 + * David Mueller, ELSOFT AG, d.mueller@elsoft.ch + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include +#include +#include +#include "s3c24x0_i2c.h" + +DECLARE_GLOBAL_DATA_PTR; + +/* 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) + +#define HSI2C_TIMEOUT_US 10000 /* 10 ms, finer granularity */ + +/* + * 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 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_EXYNOS4 || defined CONFIG_EXYNOS5) + clkin = get_i2c_clk(); +#else + clkin = get_PCLK(); +#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 -EINVAL; +} + +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); +} + +/* + * 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; +} + +static int exynos_hs_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, + int nmsgs) +{ + struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); + struct exynos5_hsi2c *hsregs = i2c_bus->hsregs; + int ret; + + for (; nmsgs > 0; nmsgs--, msg++) { + if (msg->flags & I2C_M_RD) { + ret = hsi2c_read(hsregs, msg->addr, 0, 0, msg->buf, + msg->len); + } else { + ret = hsi2c_write(hsregs, msg->addr, 0, 0, msg->buf, + msg->len, true); + } + if (ret) { + exynos5_i2c_reset(i2c_bus); + return -EREMOTEIO; + } + } + + return 0; +} + +static int s3c24x0_i2c_set_bus_speed(struct udevice *dev, unsigned int speed) +{ + struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); + + i2c_bus->clock_frequency = speed; + + if (hsi2c_get_clk_details(i2c_bus)) + return -EFAULT; + hsi2c_ch_init(i2c_bus); + + return 0; +} + +static int s3c24x0_i2c_probe(struct udevice *dev, uint chip, uint chip_flags) +{ + struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); + uchar buf[1]; + int ret; + + 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). + */ + ret = hsi2c_read(i2c_bus->hsregs, chip, 0, 0, buf, 1); + + return ret != I2C_OK; +} + +static int s3c_i2c_ofdata_to_platdata(struct udevice *dev) +{ + const void *blob = gd->fdt_blob; + struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); + int node; + + node = dev->of_offset; + + i2c_bus->hsregs = (struct exynos5_hsi2c *)dev_get_addr(dev); + + i2c_bus->id = pinmux_decode_periph_id(blob, node); + + i2c_bus->clock_frequency = fdtdec_get_int(blob, node, + "clock-frequency", 100000); + i2c_bus->node = node; + i2c_bus->bus_num = dev->seq; + + exynos_pinmux_config(i2c_bus->id, PINMUX_FLAG_HS_MODE); + + i2c_bus->active = true; + + return 0; +} + +static const struct dm_i2c_ops exynos_hs_i2c_ops = { + .xfer = exynos_hs_i2c_xfer, + .probe_chip = s3c24x0_i2c_probe, + .set_bus_speed = s3c24x0_i2c_set_bus_speed, +}; + +static const struct udevice_id exynos_hs_i2c_ids[] = { + { .compatible = "samsung,exynos5-hsi2c" }, + { } +}; + +U_BOOT_DRIVER(hs_i2c) = { + .name = "i2c_s3c_hs", + .id = UCLASS_I2C, + .of_match = exynos_hs_i2c_ids, + .ofdata_to_platdata = s3c_i2c_ofdata_to_platdata, + .priv_auto_alloc_size = sizeof(struct s3c24x0_i2c_bus), + .ops = &exynos_hs_i2c_ops, +}; diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index 24fc984..2ece9f4 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -24,105 +24,8 @@ #include #include "s3c24x0_i2c.h" -#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 10 /* 10 ms */ - -#define HSI2C_TIMEOUT_US 10000 /* 10 ms, finer granularity */ - DECLARE_GLOBAL_DATA_PTR; -enum exynos_i2c_type { - EXYNOS_I2C_STD, - EXYNOS_I2C_HS, -}; - /* * Wait til the byte transfer is completed. * @@ -145,55 +48,6 @@ static int WaitForXfer(struct s3c24x0_i2c *i2c) 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 read_write_byte(struct s3c24x0_i2c *i2c) { clrbits_le32(&i2c->iiccon, I2CCON_IRPND); @@ -226,344 +80,14 @@ static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd) writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat); } -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_EXYNOS4 || defined CONFIG_EXYNOS5) - clkin = get_i2c_clk(); -#else - clkin = get_PCLK(); -#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 -EINVAL; -} - -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); -} - -/* - * 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; -} - static int s3c24x0_i2c_set_bus_speed(struct udevice *dev, unsigned int speed) { struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); i2c_bus->clock_frequency = speed; - if (i2c_bus->is_highspeed) { - if (hsi2c_get_clk_details(i2c_bus)) - return -EFAULT; - hsi2c_ch_init(i2c_bus); - } else { - i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency, - CONFIG_SYS_I2C_S3C24X0_SLAVE); - } + i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency, + CONFIG_SYS_I2C_S3C24X0_SLAVE); return 0; } @@ -693,41 +217,11 @@ static int s3c24x0_i2c_probe(struct udevice *dev, uint chip, uint chip_flags) * 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); - } + ret = i2c_transfer(i2c_bus->regs, I2C_READ, chip << 1, 0, 0, buf, 1); return ret != I2C_OK; } -static int exynos_hs_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, - int nmsgs) -{ - struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); - struct exynos5_hsi2c *hsregs = i2c_bus->hsregs; - int ret; - - for (; nmsgs > 0; nmsgs--, msg++) { - if (msg->flags & I2C_M_RD) { - ret = hsi2c_read(hsregs, msg->addr, 0, 0, msg->buf, - msg->len); - } else { - ret = hsi2c_write(hsregs, msg->addr, 0, 0, msg->buf, - msg->len, true); - } - if (ret) { - exynos5_i2c_reset(i2c_bus); - return -EREMOTEIO; - } - } - - return 0; -} - static int s3c24x0_do_msg(struct s3c24x0_i2c_bus *i2c_bus, struct i2c_msg *msg, int seq) { @@ -810,18 +304,11 @@ static int s3c_i2c_ofdata_to_platdata(struct udevice *dev) { const void *blob = gd->fdt_blob; struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev); - int node, flags; + int node; - i2c_bus->is_highspeed = dev_get_driver_data(dev); node = dev->of_offset; - if (i2c_bus->is_highspeed) { - flags = PINMUX_FLAG_HS_MODE; - i2c_bus->hsregs = (struct exynos5_hsi2c *)dev_get_addr(dev); - } else { - flags = 0; - i2c_bus->regs = (struct s3c24x0_i2c *)dev_get_addr(dev); - } + i2c_bus->regs = (struct s3c24x0_i2c *)dev_get_addr(dev); i2c_bus->id = pinmux_decode_periph_id(blob, node); @@ -830,7 +317,7 @@ static int s3c_i2c_ofdata_to_platdata(struct udevice *dev) i2c_bus->node = node; i2c_bus->bus_num = dev->seq; - exynos_pinmux_config(i2c_bus->id, flags); + exynos_pinmux_config(i2c_bus->id, 0); i2c_bus->active = true; @@ -844,7 +331,7 @@ static const struct dm_i2c_ops s3c_i2c_ops = { }; static const struct udevice_id s3c_i2c_ids[] = { - { .compatible = "samsung,s3c2440-i2c", .data = EXYNOS_I2C_STD }, + { .compatible = "samsung,s3c2440-i2c" }, { } }; @@ -856,27 +343,3 @@ U_BOOT_DRIVER(i2c_s3c) = { .priv_auto_alloc_size = sizeof(struct s3c24x0_i2c_bus), .ops = &s3c_i2c_ops, }; - -/* - * TODO(sjg@chromium.org): Move this to a separate file when everything uses - * driver model - */ -static const struct dm_i2c_ops exynos_hs_i2c_ops = { - .xfer = exynos_hs_i2c_xfer, - .probe_chip = s3c24x0_i2c_probe, - .set_bus_speed = s3c24x0_i2c_set_bus_speed, -}; - -static const struct udevice_id exynos_hs_i2c_ids[] = { - { .compatible = "samsung,exynos5-hsi2c", .data = EXYNOS_I2C_HS }, - { } -}; - -U_BOOT_DRIVER(hs_i2c) = { - .name = "i2c_s3c_hs", - .id = UCLASS_I2C, - .of_match = exynos_hs_i2c_ids, - .ofdata_to_platdata = s3c_i2c_ofdata_to_platdata, - .priv_auto_alloc_size = sizeof(struct s3c24x0_i2c_bus), - .ops = &exynos_hs_i2c_ops, -}; diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h index 1ae73d2..aa10fc7 100644 --- a/drivers/i2c/s3c24x0_i2c.h +++ b/drivers/i2c/s3c24x0_i2c.h @@ -59,4 +59,26 @@ struct s3c24x0_i2c_bus { unsigned clk_cycle; unsigned clk_div; }; + +#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 */ + +/* 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 10 /* 10 ms */ + #endif /* _S3C24X0_I2C_H */