diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-core.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.c | 705 |
1 files changed, 705 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c new file mode 100644 index 00000000000..df879924100 --- /dev/null +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -0,0 +1,705 @@ +/* + * Synopsys DesignWare I2C adapter driver (master only). + * + * Based on the TI DAVINCI I2C adapter driver. + * + * Copyright (C) 2006 Texas Instruments. + * Copyright (C) 2007 MontaVista Software Inc. + * Copyright (C) 2009 Provigent Ltd. + * + * ---------------------------------------------------------------------------- + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * ---------------------------------------------------------------------------- + * + */ +#include <linux/clk.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/pm_runtime.h> +#include <linux/delay.h> +#include "i2c-designware-core.h" + +/* + * Registers offset + */ +#define DW_IC_CON 0x0 +#define DW_IC_TAR 0x4 +#define DW_IC_DATA_CMD 0x10 +#define DW_IC_SS_SCL_HCNT 0x14 +#define DW_IC_SS_SCL_LCNT 0x18 +#define DW_IC_FS_SCL_HCNT 0x1c +#define DW_IC_FS_SCL_LCNT 0x20 +#define DW_IC_INTR_STAT 0x2c +#define DW_IC_INTR_MASK 0x30 +#define DW_IC_RAW_INTR_STAT 0x34 +#define DW_IC_RX_TL 0x38 +#define DW_IC_TX_TL 0x3c +#define DW_IC_CLR_INTR 0x40 +#define DW_IC_CLR_RX_UNDER 0x44 +#define DW_IC_CLR_RX_OVER 0x48 +#define DW_IC_CLR_TX_OVER 0x4c +#define DW_IC_CLR_RD_REQ 0x50 +#define DW_IC_CLR_TX_ABRT 0x54 +#define DW_IC_CLR_RX_DONE 0x58 +#define DW_IC_CLR_ACTIVITY 0x5c +#define DW_IC_CLR_STOP_DET 0x60 +#define DW_IC_CLR_START_DET 0x64 +#define DW_IC_CLR_GEN_CALL 0x68 +#define DW_IC_ENABLE 0x6c +#define DW_IC_STATUS 0x70 +#define DW_IC_TXFLR 0x74 +#define DW_IC_RXFLR 0x78 +#define DW_IC_TX_ABRT_SOURCE 0x80 +#define DW_IC_COMP_PARAM_1 0xf4 +#define DW_IC_COMP_TYPE 0xfc +#define DW_IC_COMP_TYPE_VALUE 0x44570140 + +#define DW_IC_INTR_RX_UNDER 0x001 +#define DW_IC_INTR_RX_OVER 0x002 +#define DW_IC_INTR_RX_FULL 0x004 +#define DW_IC_INTR_TX_OVER 0x008 +#define DW_IC_INTR_TX_EMPTY 0x010 +#define DW_IC_INTR_RD_REQ 0x020 +#define DW_IC_INTR_TX_ABRT 0x040 +#define DW_IC_INTR_RX_DONE 0x080 +#define DW_IC_INTR_ACTIVITY 0x100 +#define DW_IC_INTR_STOP_DET 0x200 +#define DW_IC_INTR_START_DET 0x400 +#define DW_IC_INTR_GEN_CALL 0x800 + +#define DW_IC_INTR_DEFAULT_MASK (DW_IC_INTR_RX_FULL | \ + DW_IC_INTR_TX_EMPTY | \ + DW_IC_INTR_TX_ABRT | \ + DW_IC_INTR_STOP_DET) + +#define DW_IC_STATUS_ACTIVITY 0x1 + +#define DW_IC_ERR_TX_ABRT 0x1 + +/* + * status codes + */ +#define STATUS_IDLE 0x0 +#define STATUS_WRITE_IN_PROGRESS 0x1 +#define STATUS_READ_IN_PROGRESS 0x2 + +#define TIMEOUT 20 /* ms */ + +/* + * hardware abort codes from the DW_IC_TX_ABRT_SOURCE register + * + * only expected abort codes are listed here + * refer to the datasheet for the full list + */ +#define ABRT_7B_ADDR_NOACK 0 +#define ABRT_10ADDR1_NOACK 1 +#define ABRT_10ADDR2_NOACK 2 +#define ABRT_TXDATA_NOACK 3 +#define ABRT_GCALL_NOACK 4 +#define ABRT_GCALL_READ 5 +#define ABRT_SBYTE_ACKDET 7 +#define ABRT_SBYTE_NORSTRT 9 +#define ABRT_10B_RD_NORSTRT 10 +#define ABRT_MASTER_DIS 11 +#define ARB_LOST 12 + +#define DW_IC_TX_ABRT_7B_ADDR_NOACK (1UL << ABRT_7B_ADDR_NOACK) +#define DW_IC_TX_ABRT_10ADDR1_NOACK (1UL << ABRT_10ADDR1_NOACK) +#define DW_IC_TX_ABRT_10ADDR2_NOACK (1UL << ABRT_10ADDR2_NOACK) +#define DW_IC_TX_ABRT_TXDATA_NOACK (1UL << ABRT_TXDATA_NOACK) +#define DW_IC_TX_ABRT_GCALL_NOACK (1UL << ABRT_GCALL_NOACK) +#define DW_IC_TX_ABRT_GCALL_READ (1UL << ABRT_GCALL_READ) +#define DW_IC_TX_ABRT_SBYTE_ACKDET (1UL << ABRT_SBYTE_ACKDET) +#define DW_IC_TX_ABRT_SBYTE_NORSTRT (1UL << ABRT_SBYTE_NORSTRT) +#define DW_IC_TX_ABRT_10B_RD_NORSTRT (1UL << ABRT_10B_RD_NORSTRT) +#define DW_IC_TX_ABRT_MASTER_DIS (1UL << ABRT_MASTER_DIS) +#define DW_IC_TX_ARB_LOST (1UL << ARB_LOST) + +#define DW_IC_TX_ABRT_NOACK (DW_IC_TX_ABRT_7B_ADDR_NOACK | \ + DW_IC_TX_ABRT_10ADDR1_NOACK | \ + DW_IC_TX_ABRT_10ADDR2_NOACK | \ + DW_IC_TX_ABRT_TXDATA_NOACK | \ + DW_IC_TX_ABRT_GCALL_NOACK) + +static char *abort_sources[] = { + [ABRT_7B_ADDR_NOACK] = + "slave address not acknowledged (7bit mode)", + [ABRT_10ADDR1_NOACK] = + "first address byte not acknowledged (10bit mode)", + [ABRT_10ADDR2_NOACK] = + "second address byte not acknowledged (10bit mode)", + [ABRT_TXDATA_NOACK] = + "data not acknowledged", + [ABRT_GCALL_NOACK] = + "no acknowledgement for a general call", + [ABRT_GCALL_READ] = + "read after general call", + [ABRT_SBYTE_ACKDET] = + "start byte acknowledged", + [ABRT_SBYTE_NORSTRT] = + "trying to send start byte when restart is disabled", + [ABRT_10B_RD_NORSTRT] = + "trying to read when restart is disabled (10bit mode)", + [ABRT_MASTER_DIS] = + "trying to use disabled adapter", + [ARB_LOST] = + "lost arbitration", +}; + +u32 dw_readl(struct dw_i2c_dev *dev, int offset) +{ + u32 value = readl(dev->base + offset); + + if (dev->swab) + return swab32(value); + else + return value; +} + +void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset) +{ + if (dev->swab) + b = swab32(b); + + writel(b, dev->base + offset); +} + +static u32 +i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset) +{ + /* + * DesignWare I2C core doesn't seem to have solid strategy to meet + * the tHD;STA timing spec. Configuring _HCNT based on tHIGH spec + * will result in violation of the tHD;STA spec. + */ + if (cond) + /* + * Conditional expression: + * + * IC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH + * + * This is based on the DW manuals, and represents an ideal + * configuration. The resulting I2C bus speed will be + * faster than any of the others. + * + * If your hardware is free from tHD;STA issue, try this one. + */ + return (ic_clk * tSYMBOL + 5000) / 10000 - 8 + offset; + else + /* + * Conditional expression: + * + * IC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf) + * + * This is just experimental rule; the tHD;STA period turned + * out to be proportinal to (_HCNT + 3). With this setting, + * we could meet both tHIGH and tHD;STA timing specs. + * + * If unsure, you'd better to take this alternative. + * + * The reason why we need to take into account "tf" here, + * is the same as described in i2c_dw_scl_lcnt(). + */ + return (ic_clk * (tSYMBOL + tf) + 5000) / 10000 - 3 + offset; +} + +static u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset) +{ + /* + * Conditional expression: + * + * IC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf) + * + * DW I2C core starts counting the SCL CNTs for the LOW period + * of the SCL clock (tLOW) as soon as it pulls the SCL line. + * In order to meet the tLOW timing spec, we need to take into + * account the fall time of SCL signal (tf). Default tf value + * should be 0.3 us, for safety. + */ + return ((ic_clk * (tLOW + tf) + 5000) / 10000) - 1 + offset; +} + +/** + * i2c_dw_init() - initialize the designware i2c master hardware + * @dev: device private data + * + * This functions configures and enables the I2C master. + * This function is called during I2C init function, and in case of timeout at + * run time. + */ +int i2c_dw_init(struct dw_i2c_dev *dev) +{ + u32 input_clock_khz; + u32 hcnt, lcnt; + u32 reg; + + input_clock_khz = dev->get_clk_rate_khz(dev); + + /* Configure register endianess access */ + reg = dw_readl(dev, DW_IC_COMP_TYPE); + if (reg == ___constant_swab32(DW_IC_COMP_TYPE_VALUE)) { + dev->swab = 1; + reg = DW_IC_COMP_TYPE_VALUE; + } + + if (reg != DW_IC_COMP_TYPE_VALUE) { + dev_err(dev->dev, "Unknown Synopsys component type: " + "0x%08x\n", reg); + return -ENODEV; + } + + /* Disable the adapter */ + dw_writel(dev, 0, DW_IC_ENABLE); + + /* set standard and fast speed deviders for high/low periods */ + + /* Standard-mode */ + hcnt = i2c_dw_scl_hcnt(input_clock_khz, + 40, /* tHD;STA = tHIGH = 4.0 us */ + 3, /* tf = 0.3 us */ + 0, /* 0: DW default, 1: Ideal */ + 0); /* No offset */ + lcnt = i2c_dw_scl_lcnt(input_clock_khz, + 47, /* tLOW = 4.7 us */ + 3, /* tf = 0.3 us */ + 0); /* No offset */ + dw_writel(dev, hcnt, DW_IC_SS_SCL_HCNT); + dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT); + dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); + + /* Fast-mode */ + hcnt = i2c_dw_scl_hcnt(input_clock_khz, + 6, /* tHD;STA = tHIGH = 0.6 us */ + 3, /* tf = 0.3 us */ + 0, /* 0: DW default, 1: Ideal */ + 0); /* No offset */ + lcnt = i2c_dw_scl_lcnt(input_clock_khz, + 13, /* tLOW = 1.3 us */ + 3, /* tf = 0.3 us */ + 0); /* No offset */ + dw_writel(dev, hcnt, DW_IC_FS_SCL_HCNT); + dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT); + dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt); + + /* Configure Tx/Rx FIFO threshold levels */ + dw_writel(dev, dev->tx_fifo_depth - 1, DW_IC_TX_TL); + dw_writel(dev, 0, DW_IC_RX_TL); + + /* configure the i2c master */ + dw_writel(dev, dev->master_cfg , DW_IC_CON); + return 0; +} + +/* + * Waiting for bus not busy + */ +static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev) +{ + int timeout = TIMEOUT; + + while (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) { + if (timeout <= 0) { + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + return -ETIMEDOUT; + } + timeout--; + mdelay(1); + } + + return 0; +} + +static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + u32 ic_con; + + /* Disable the adapter */ + dw_writel(dev, 0, DW_IC_ENABLE); + + /* set the slave (target) address */ + dw_writel(dev, msgs[dev->msg_write_idx].addr, DW_IC_TAR); + + /* if the slave address is ten bit address, enable 10BITADDR */ + ic_con = dw_readl(dev, DW_IC_CON); + if (msgs[dev->msg_write_idx].flags & I2C_M_TEN) + ic_con |= DW_IC_CON_10BITADDR_MASTER; + else + ic_con &= ~DW_IC_CON_10BITADDR_MASTER; + dw_writel(dev, ic_con, DW_IC_CON); + + /* Enable the adapter */ + dw_writel(dev, 1, DW_IC_ENABLE); + + /* Enable interrupts */ + dw_writel(dev, DW_IC_INTR_DEFAULT_MASK, DW_IC_INTR_MASK); +} + +/* + * Initiate (and continue) low level master read/write transaction. + * This function is only called from i2c_dw_isr, and pumping i2c_msg + * messages into the tx buffer. Even if the size of i2c_msg data is + * longer than the size of the tx buffer, it handles everything. + */ +void +i2c_dw_xfer_msg(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + u32 intr_mask; + int tx_limit, rx_limit; + u32 addr = msgs[dev->msg_write_idx].addr; + u32 buf_len = dev->tx_buf_len; + u8 *buf = dev->tx_buf; + + intr_mask = DW_IC_INTR_DEFAULT_MASK; + + for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) { + /* + * if target address has changed, we need to + * reprogram the target address in the i2c + * adapter when we are done with this transfer + */ + if (msgs[dev->msg_write_idx].addr != addr) { + dev_err(dev->dev, + "%s: invalid target address\n", __func__); + dev->msg_err = -EINVAL; + break; + } + + if (msgs[dev->msg_write_idx].len == 0) { + dev_err(dev->dev, + "%s: invalid message length\n", __func__); + dev->msg_err = -EINVAL; + break; + } + + if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) { + /* new i2c_msg */ + buf = msgs[dev->msg_write_idx].buf; + buf_len = msgs[dev->msg_write_idx].len; + } + + tx_limit = dev->tx_fifo_depth - dw_readl(dev, DW_IC_TXFLR); + rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR); + + while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) { + if (msgs[dev->msg_write_idx].flags & I2C_M_RD) { + dw_writel(dev, 0x100, DW_IC_DATA_CMD); + rx_limit--; + } else + dw_writel(dev, *buf++, DW_IC_DATA_CMD); + tx_limit--; buf_len--; + } + + dev->tx_buf = buf; + dev->tx_buf_len = buf_len; + + if (buf_len > 0) { + /* more bytes to be written */ + dev->status |= STATUS_WRITE_IN_PROGRESS; + break; + } else + dev->status &= ~STATUS_WRITE_IN_PROGRESS; + } + + /* + * If i2c_msg index search is completed, we don't need TX_EMPTY + * interrupt any more. + */ + if (dev->msg_write_idx == dev->msgs_num) + intr_mask &= ~DW_IC_INTR_TX_EMPTY; + + if (dev->msg_err) + intr_mask = 0; + + dw_writel(dev, intr_mask, DW_IC_INTR_MASK); +} + +static void +i2c_dw_read(struct dw_i2c_dev *dev) +{ + struct i2c_msg *msgs = dev->msgs; + int rx_valid; + + for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) { + u32 len; + u8 *buf; + + if (!(msgs[dev->msg_read_idx].flags & I2C_M_RD)) + continue; + + if (!(dev->status & STATUS_READ_IN_PROGRESS)) { + len = msgs[dev->msg_read_idx].len; + buf = msgs[dev->msg_read_idx].buf; + } else { + len = dev->rx_buf_len; + buf = dev->rx_buf; + } + + rx_valid = dw_readl(dev, DW_IC_RXFLR); + + for (; len > 0 && rx_valid > 0; len--, rx_valid--) + *buf++ = dw_readl(dev, DW_IC_DATA_CMD); + + if (len > 0) { + dev->status |= STATUS_READ_IN_PROGRESS; + dev->rx_buf_len = len; + dev->rx_buf = buf; + return; + } else + dev->status &= ~STATUS_READ_IN_PROGRESS; + } +} + +static int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev) +{ + unsigned long abort_source = dev->abort_source; + int i; + + if (abort_source & DW_IC_TX_ABRT_NOACK) { + for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) + dev_dbg(dev->dev, + "%s: %s\n", __func__, abort_sources[i]); + return -EREMOTEIO; + } + + for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources)) + dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]); + + if (abort_source & DW_IC_TX_ARB_LOST) + return -EAGAIN; + else if (abort_source & DW_IC_TX_ABRT_GCALL_READ) + return -EINVAL; /* wrong msgs[] data */ + else + return -EIO; +} + +/* + * Prepare controller for a transaction and call i2c_dw_xfer_msg + */ +int +i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + int ret; + + dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); + + mutex_lock(&dev->lock); + pm_runtime_get_sync(dev->dev); + + INIT_COMPLETION(dev->cmd_complete); + dev->msgs = msgs; + dev->msgs_num = num; + dev->cmd_err = 0; + dev->msg_write_idx = 0; + dev->msg_read_idx = 0; + dev->msg_err = 0; + dev->status = STATUS_IDLE; + dev->abort_source = 0; + + ret = i2c_dw_wait_bus_not_busy(dev); + if (ret < 0) + goto done; + + /* start the transfers */ + i2c_dw_xfer_init(dev); + + /* wait for tx to complete */ + ret = wait_for_completion_interruptible_timeout(&dev->cmd_complete, HZ); + if (ret == 0) { + dev_err(dev->dev, "controller timed out\n"); + i2c_dw_init(dev); + ret = -ETIMEDOUT; + goto done; + } else if (ret < 0) + goto done; + + if (dev->msg_err) { + ret = dev->msg_err; + goto done; + } + + /* no error */ + if (likely(!dev->cmd_err)) { + /* Disable the adapter */ + dw_writel(dev, 0, DW_IC_ENABLE); + ret = num; + goto done; + } + + /* We have an error */ + if (dev->cmd_err == DW_IC_ERR_TX_ABRT) { + ret = i2c_dw_handle_tx_abort(dev); + goto done; + } + ret = -EIO; + +done: + pm_runtime_put(dev->dev); + mutex_unlock(&dev->lock); + + return ret; +} + +u32 i2c_dw_func(struct i2c_adapter *adap) +{ + struct dw_i2c_dev *dev = i2c_get_adapdata(adap); + return dev->functionality; +} + +static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev) +{ + u32 stat; + + /* + * The IC_INTR_STAT register just indicates "enabled" interrupts. + * Ths unmasked raw version of interrupt status bits are available + * in the IC_RAW_INTR_STAT register. + * + * That is, + * stat = dw_readl(IC_INTR_STAT); + * equals to, + * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK); + * + * The raw version might be useful for debugging purposes. + */ + stat = dw_readl(dev, DW_IC_INTR_STAT); + + /* + * Do not use the IC_CLR_INTR register to clear interrupts, or + * you'll miss some interrupts, triggered during the period from + * dw_readl(IC_INTR_STAT) to dw_readl(IC_CLR_INTR). + * + * Instead, use the separately-prepared IC_CLR_* registers. + */ + if (stat & DW_IC_INTR_RX_UNDER) + dw_readl(dev, DW_IC_CLR_RX_UNDER); + if (stat & DW_IC_INTR_RX_OVER) + dw_readl(dev, DW_IC_CLR_RX_OVER); + if (stat & DW_IC_INTR_TX_OVER) + dw_readl(dev, DW_IC_CLR_TX_OVER); + if (stat & DW_IC_INTR_RD_REQ) + dw_readl(dev, DW_IC_CLR_RD_REQ); + if (stat & DW_IC_INTR_TX_ABRT) { + /* + * The IC_TX_ABRT_SOURCE register is cleared whenever + * the IC_CLR_TX_ABRT is read. Preserve it beforehand. + */ + dev->abort_source = dw_readl(dev, DW_IC_TX_ABRT_SOURCE); + dw_readl(dev, DW_IC_CLR_TX_ABRT); + } + if (stat & DW_IC_INTR_RX_DONE) + dw_readl(dev, DW_IC_CLR_RX_DONE); + if (stat & DW_IC_INTR_ACTIVITY) + dw_readl(dev, DW_IC_CLR_ACTIVITY); + if (stat & DW_IC_INTR_STOP_DET) + dw_readl(dev, DW_IC_CLR_STOP_DET); + if (stat & DW_IC_INTR_START_DET) + dw_readl(dev, DW_IC_CLR_START_DET); + if (stat & DW_IC_INTR_GEN_CALL) + dw_readl(dev, DW_IC_CLR_GEN_CALL); + + return stat; +} + +/* + * Interrupt service routine. This gets called whenever an I2C interrupt + * occurs. + */ +irqreturn_t i2c_dw_isr(int this_irq, void *dev_id) +{ + struct dw_i2c_dev *dev = dev_id; + u32 stat, enabled; + + enabled = dw_readl(dev, DW_IC_ENABLE); + stat = dw_readl(dev, DW_IC_RAW_INTR_STAT); + dev_dbg(dev->dev, "%s: %s enabled= 0x%x stat=0x%x\n", __func__, + dev->adapter.name, enabled, stat); + if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY)) + return IRQ_NONE; + + stat = i2c_dw_read_clear_intrbits(dev); + + if (stat & DW_IC_INTR_TX_ABRT) { + dev->cmd_err |= DW_IC_ERR_TX_ABRT; + dev->status = STATUS_IDLE; + + /* + * Anytime TX_ABRT is set, the contents of the tx/rx + * buffers are flushed. Make sure to skip them. + */ + dw_writel(dev, 0, DW_IC_INTR_MASK); + goto tx_aborted; + } + + if (stat & DW_IC_INTR_RX_FULL) + i2c_dw_read(dev); + + if (stat & DW_IC_INTR_TX_EMPTY) + i2c_dw_xfer_msg(dev); + + /* + * No need to modify or disable the interrupt mask here. + * i2c_dw_xfer_msg() will take care of it according to + * the current transmit status. + */ + +tx_aborted: + if ((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err) + complete(&dev->cmd_complete); + + return IRQ_HANDLED; +} + +void i2c_dw_enable(struct dw_i2c_dev *dev) +{ + /* Enable the adapter */ + dw_writel(dev, 1, DW_IC_ENABLE); +} + +u32 i2c_dw_is_enabled(struct dw_i2c_dev *dev) +{ + return dw_readl(dev, DW_IC_ENABLE); +} + +void i2c_dw_disable(struct dw_i2c_dev *dev) +{ + /* Disable controller */ + dw_writel(dev, 0, DW_IC_ENABLE); + + /* Disable all interupts */ + dw_writel(dev, 0, DW_IC_INTR_MASK); + dw_readl(dev, DW_IC_CLR_INTR); +} + +void i2c_dw_clear_int(struct dw_i2c_dev *dev) +{ + dw_readl(dev, DW_IC_CLR_INTR); +} + +void i2c_dw_disable_int(struct dw_i2c_dev *dev) +{ + dw_writel(dev, 0, DW_IC_INTR_MASK); +} + +u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev) +{ + return dw_readl(dev, DW_IC_COMP_PARAM_1); +} |