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Diffstat (limited to 'drivers/i2c/busses/i2c-designware.c')
-rw-r--r--drivers/i2c/busses/i2c-designware.c847
1 files changed, 0 insertions, 847 deletions
diff --git a/drivers/i2c/busses/i2c-designware.c b/drivers/i2c/busses/i2c-designware.c
deleted file mode 100644
index b7a51c4..0000000
--- a/drivers/i2c/busses/i2c-designware.c
+++ /dev/null
@@ -1,847 +0,0 @@
-/*
- * 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/kernel.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/clk.h>
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/err.h>
-#include <linux/interrupt.h>
-#include <linux/platform_device.h>
-#include <linux/io.h>
-#include <linux/slab.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_COMP_PARAM_1 0xf4
-#define DW_IC_TX_ABRT_SOURCE 0x80
-
-#define DW_IC_CON_MASTER 0x1
-#define DW_IC_CON_SPEED_STD 0x2
-#define DW_IC_CON_SPEED_FAST 0x4
-#define DW_IC_CON_10BITADDR_MASTER 0x10
-#define DW_IC_CON_RESTART_EN 0x20
-#define DW_IC_CON_SLAVE_DISABLE 0x40
-
-#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",
-};
-
-/**
- * struct dw_i2c_dev - private i2c-designware data
- * @dev: driver model device node
- * @base: IO registers pointer
- * @cmd_complete: tx completion indicator
- * @lock: protect this struct and IO registers
- * @clk: input reference clock
- * @cmd_err: run time hadware error code
- * @msgs: points to an array of messages currently being transferred
- * @msgs_num: the number of elements in msgs
- * @msg_write_idx: the element index of the current tx message in the msgs
- * array
- * @tx_buf_len: the length of the current tx buffer
- * @tx_buf: the current tx buffer
- * @msg_read_idx: the element index of the current rx message in the msgs
- * array
- * @rx_buf_len: the length of the current rx buffer
- * @rx_buf: the current rx buffer
- * @msg_err: error status of the current transfer
- * @status: i2c master status, one of STATUS_*
- * @abort_source: copy of the TX_ABRT_SOURCE register
- * @irq: interrupt number for the i2c master
- * @adapter: i2c subsystem adapter node
- * @tx_fifo_depth: depth of the hardware tx fifo
- * @rx_fifo_depth: depth of the hardware rx fifo
- */
-struct dw_i2c_dev {
- struct device *dev;
- void __iomem *base;
- struct completion cmd_complete;
- struct mutex lock;
- struct clk *clk;
- int cmd_err;
- struct i2c_msg *msgs;
- int msgs_num;
- int msg_write_idx;
- u32 tx_buf_len;
- u8 *tx_buf;
- int msg_read_idx;
- u32 rx_buf_len;
- u8 *rx_buf;
- int msg_err;
- unsigned int status;
- u32 abort_source;
- int irq;
- struct i2c_adapter adapter;
- unsigned int tx_fifo_depth;
- unsigned int rx_fifo_depth;
-};
-
-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.
- */
-static void i2c_dw_init(struct dw_i2c_dev *dev)
-{
- u32 input_clock_khz = clk_get_rate(dev->clk) / 1000;
- u32 ic_con, hcnt, lcnt;
-
- /* Disable the adapter */
- writel(0, dev->base + 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 */
- writel(hcnt, dev->base + DW_IC_SS_SCL_HCNT);
- writel(lcnt, dev->base + 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 */
- writel(hcnt, dev->base + DW_IC_FS_SCL_HCNT);
- writel(lcnt, dev->base + DW_IC_FS_SCL_LCNT);
- dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
-
- /* Configure Tx/Rx FIFO threshold levels */
- writel(dev->tx_fifo_depth - 1, dev->base + DW_IC_TX_TL);
- writel(0, dev->base + DW_IC_RX_TL);
-
- /* configure the i2c master */
- ic_con = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
- DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
- writel(ic_con, dev->base + DW_IC_CON);
-}
-
-/*
- * Waiting for bus not busy
- */
-static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
-{
- int timeout = TIMEOUT;
-
- while (readl(dev->base + 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 */
- writel(0, dev->base + DW_IC_ENABLE);
-
- /* set the slave (target) address */
- writel(msgs[dev->msg_write_idx].addr, dev->base + DW_IC_TAR);
-
- /* if the slave address is ten bit address, enable 10BITADDR */
- ic_con = readl(dev->base + 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;
- writel(ic_con, dev->base + DW_IC_CON);
-
- /* Enable the adapter */
- writel(1, dev->base + DW_IC_ENABLE);
-
- /* Enable interrupts */
- writel(DW_IC_INTR_DEFAULT_MASK, dev->base + 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.
- */
-static 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 - readl(dev->base + DW_IC_TXFLR);
- rx_limit = dev->rx_fifo_depth - readl(dev->base + DW_IC_RXFLR);
-
- while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
- if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
- writel(0x100, dev->base + DW_IC_DATA_CMD);
- rx_limit--;
- } else
- writel(*buf++, dev->base + 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;
-
- writel(intr_mask, dev->base + 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 = readl(dev->base + DW_IC_RXFLR);
-
- for (; len > 0 && rx_valid > 0; len--, rx_valid--)
- *buf++ = readl(dev->base + 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
- */
-static 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);
-
- 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 */
- writel(0, dev->base + 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:
- mutex_unlock(&dev->lock);
-
- return ret;
-}
-
-static u32 i2c_dw_func(struct i2c_adapter *adap)
-{
- return I2C_FUNC_I2C |
- I2C_FUNC_10BIT_ADDR |
- I2C_FUNC_SMBUS_BYTE |
- I2C_FUNC_SMBUS_BYTE_DATA |
- I2C_FUNC_SMBUS_WORD_DATA |
- I2C_FUNC_SMBUS_I2C_BLOCK;
-}
-
-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 = readl(IC_INTR_STAT);
- * equals to,
- * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK);
- *
- * The raw version might be useful for debugging purposes.
- */
- stat = readl(dev->base + 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
- * readl(IC_INTR_STAT) to readl(IC_CLR_INTR).
- *
- * Instead, use the separately-prepared IC_CLR_* registers.
- */
- if (stat & DW_IC_INTR_RX_UNDER)
- readl(dev->base + DW_IC_CLR_RX_UNDER);
- if (stat & DW_IC_INTR_RX_OVER)
- readl(dev->base + DW_IC_CLR_RX_OVER);
- if (stat & DW_IC_INTR_TX_OVER)
- readl(dev->base + DW_IC_CLR_TX_OVER);
- if (stat & DW_IC_INTR_RD_REQ)
- readl(dev->base + 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 = readl(dev->base + DW_IC_TX_ABRT_SOURCE);
- readl(dev->base + DW_IC_CLR_TX_ABRT);
- }
- if (stat & DW_IC_INTR_RX_DONE)
- readl(dev->base + DW_IC_CLR_RX_DONE);
- if (stat & DW_IC_INTR_ACTIVITY)
- readl(dev->base + DW_IC_CLR_ACTIVITY);
- if (stat & DW_IC_INTR_STOP_DET)
- readl(dev->base + DW_IC_CLR_STOP_DET);
- if (stat & DW_IC_INTR_START_DET)
- readl(dev->base + DW_IC_CLR_START_DET);
- if (stat & DW_IC_INTR_GEN_CALL)
- readl(dev->base + DW_IC_CLR_GEN_CALL);
-
- return stat;
-}
-
-/*
- * Interrupt service routine. This gets called whenever an I2C interrupt
- * occurs.
- */
-static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
-{
- struct dw_i2c_dev *dev = dev_id;
- u32 stat;
-
- stat = i2c_dw_read_clear_intrbits(dev);
- dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat);
-
- 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.
- */
- writel(0, dev->base + 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;
-}
-
-static struct i2c_algorithm i2c_dw_algo = {
- .master_xfer = i2c_dw_xfer,
- .functionality = i2c_dw_func,
-};
-
-static int __devinit dw_i2c_probe(struct platform_device *pdev)
-{
- struct dw_i2c_dev *dev;
- struct i2c_adapter *adap;
- struct resource *mem, *ioarea;
- int irq, r;
-
- /* NOTE: driver uses the static register mapping */
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!mem) {
- dev_err(&pdev->dev, "no mem resource?\n");
- return -EINVAL;
- }
-
- irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev, "no irq resource?\n");
- return irq; /* -ENXIO */
- }
-
- ioarea = request_mem_region(mem->start, resource_size(mem),
- pdev->name);
- if (!ioarea) {
- dev_err(&pdev->dev, "I2C region already claimed\n");
- return -EBUSY;
- }
-
- dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
- if (!dev) {
- r = -ENOMEM;
- goto err_release_region;
- }
-
- init_completion(&dev->cmd_complete);
- mutex_init(&dev->lock);
- dev->dev = get_device(&pdev->dev);
- dev->irq = irq;
- platform_set_drvdata(pdev, dev);
-
- dev->clk = clk_get(&pdev->dev, NULL);
- if (IS_ERR(dev->clk)) {
- r = -ENODEV;
- goto err_free_mem;
- }
- clk_enable(dev->clk);
-
- dev->base = ioremap(mem->start, resource_size(mem));
- if (dev->base == NULL) {
- dev_err(&pdev->dev, "failure mapping io resources\n");
- r = -EBUSY;
- goto err_unuse_clocks;
- }
- {
- u32 param1 = readl(dev->base + DW_IC_COMP_PARAM_1);
-
- dev->tx_fifo_depth = ((param1 >> 16) & 0xff) + 1;
- dev->rx_fifo_depth = ((param1 >> 8) & 0xff) + 1;
- }
- i2c_dw_init(dev);
-
- writel(0, dev->base + DW_IC_INTR_MASK); /* disable IRQ */
- r = request_irq(dev->irq, i2c_dw_isr, IRQF_DISABLED, pdev->name, dev);
- if (r) {
- dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
- goto err_iounmap;
- }
-
- adap = &dev->adapter;
- i2c_set_adapdata(adap, dev);
- adap->owner = THIS_MODULE;
- adap->class = I2C_CLASS_HWMON;
- strlcpy(adap->name, "Synopsys DesignWare I2C adapter",
- sizeof(adap->name));
- adap->algo = &i2c_dw_algo;
- adap->dev.parent = &pdev->dev;
-
- adap->nr = pdev->id;
- r = i2c_add_numbered_adapter(adap);
- if (r) {
- dev_err(&pdev->dev, "failure adding adapter\n");
- goto err_free_irq;
- }
-
- return 0;
-
-err_free_irq:
- free_irq(dev->irq, dev);
-err_iounmap:
- iounmap(dev->base);
-err_unuse_clocks:
- clk_disable(dev->clk);
- clk_put(dev->clk);
- dev->clk = NULL;
-err_free_mem:
- platform_set_drvdata(pdev, NULL);
- put_device(&pdev->dev);
- kfree(dev);
-err_release_region:
- release_mem_region(mem->start, resource_size(mem));
-
- return r;
-}
-
-static int __devexit dw_i2c_remove(struct platform_device *pdev)
-{
- struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
- struct resource *mem;
-
- platform_set_drvdata(pdev, NULL);
- i2c_del_adapter(&dev->adapter);
- put_device(&pdev->dev);
-
- clk_disable(dev->clk);
- clk_put(dev->clk);
- dev->clk = NULL;
-
- writel(0, dev->base + DW_IC_ENABLE);
- free_irq(dev->irq, dev);
- kfree(dev);
-
- mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(mem->start, resource_size(mem));
- return 0;
-}
-
-/* work with hotplug and coldplug */
-MODULE_ALIAS("platform:i2c_designware");
-
-static struct platform_driver dw_i2c_driver = {
- .remove = __devexit_p(dw_i2c_remove),
- .driver = {
- .name = "i2c_designware",
- .owner = THIS_MODULE,
- },
-};
-
-static int __init dw_i2c_init_driver(void)
-{
- return platform_driver_probe(&dw_i2c_driver, dw_i2c_probe);
-}
-module_init(dw_i2c_init_driver);
-
-static void __exit dw_i2c_exit_driver(void)
-{
- platform_driver_unregister(&dw_i2c_driver);
-}
-module_exit(dw_i2c_exit_driver);
-
-MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
-MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
-MODULE_LICENSE("GPL");