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path: root/drivers/i2c/busses/i2c-designware-master.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-designware-master.c')
-rw-r--r--drivers/i2c/busses/i2c-designware-master.c673
1 files changed, 673 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
new file mode 100644
index 000000000000..eefc4db1ee3e
--- /dev/null
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -0,0 +1,673 @@
+/*
+ * 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.
+ * ----------------------------------------------------------------------------
+ *
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+
+#include "i2c-designware-core.h"
+
+static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
+{
+ /* Configure Tx/Rx FIFO threshold levels */
+ dw_writel(dev, dev->tx_fifo_depth / 2, 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);
+}
+
+/**
+ * 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 hcnt, lcnt;
+ u32 reg, comp_param1;
+ u32 sda_falling_time, scl_falling_time;
+ int ret;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ return ret;
+
+ reg = dw_readl(dev, DW_IC_COMP_TYPE);
+ if (reg == ___constant_swab32(DW_IC_COMP_TYPE_VALUE)) {
+ /* Configure register endianess access */
+ dev->flags |= ACCESS_SWAP;
+ } else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) {
+ /* Configure register access mode 16bit */
+ dev->flags |= ACCESS_16BIT;
+ } else if (reg != DW_IC_COMP_TYPE_VALUE) {
+ dev_err(dev->dev,
+ "Unknown Synopsys component type: 0x%08x\n", reg);
+ i2c_dw_release_lock(dev);
+ return -ENODEV;
+ }
+
+ comp_param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
+
+ /* Disable the adapter */
+ __i2c_dw_enable_and_wait(dev, false);
+
+ /* Set standard and fast speed deviders for high/low periods */
+
+ sda_falling_time = dev->sda_falling_time ?: 300; /* ns */
+ scl_falling_time = dev->scl_falling_time ?: 300; /* ns */
+
+ /* Set SCL timing parameters for standard-mode */
+ if (dev->ss_hcnt && dev->ss_lcnt) {
+ hcnt = dev->ss_hcnt;
+ lcnt = dev->ss_lcnt;
+ } else {
+ hcnt = i2c_dw_scl_hcnt(i2c_dw_clk_rate(dev),
+ 4000, /* tHD;STA = tHIGH = 4.0 us */
+ sda_falling_time,
+ 0, /* 0: DW default, 1: Ideal */
+ 0); /* No offset */
+ lcnt = i2c_dw_scl_lcnt(i2c_dw_clk_rate(dev),
+ 4700, /* tLOW = 4.7 us */
+ scl_falling_time,
+ 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);
+
+ /* Set SCL timing parameters for fast-mode or fast-mode plus */
+ if ((dev->clk_freq == 1000000) && dev->fp_hcnt && dev->fp_lcnt) {
+ hcnt = dev->fp_hcnt;
+ lcnt = dev->fp_lcnt;
+ } else if (dev->fs_hcnt && dev->fs_lcnt) {
+ hcnt = dev->fs_hcnt;
+ lcnt = dev->fs_lcnt;
+ } else {
+ hcnt = i2c_dw_scl_hcnt(i2c_dw_clk_rate(dev),
+ 600, /* tHD;STA = tHIGH = 0.6 us */
+ sda_falling_time,
+ 0, /* 0: DW default, 1: Ideal */
+ 0); /* No offset */
+ lcnt = i2c_dw_scl_lcnt(i2c_dw_clk_rate(dev),
+ 1300, /* tLOW = 1.3 us */
+ scl_falling_time,
+ 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);
+
+ if ((dev->master_cfg & DW_IC_CON_SPEED_MASK) ==
+ DW_IC_CON_SPEED_HIGH) {
+ if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
+ != DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) {
+ dev_err(dev->dev, "High Speed not supported!\n");
+ dev->master_cfg &= ~DW_IC_CON_SPEED_MASK;
+ dev->master_cfg |= DW_IC_CON_SPEED_FAST;
+ } else if (dev->hs_hcnt && dev->hs_lcnt) {
+ hcnt = dev->hs_hcnt;
+ lcnt = dev->hs_lcnt;
+ dw_writel(dev, hcnt, DW_IC_HS_SCL_HCNT);
+ dw_writel(dev, lcnt, DW_IC_HS_SCL_LCNT);
+ dev_dbg(dev->dev, "HighSpeed-mode HCNT:LCNT = %d:%d\n",
+ hcnt, lcnt);
+ }
+ }
+
+ /* Configure SDA Hold Time if required */
+ reg = dw_readl(dev, DW_IC_COMP_VERSION);
+ if (reg >= DW_IC_SDA_HOLD_MIN_VERS) {
+ if (!dev->sda_hold_time) {
+ /* Keep previous hold time setting if no one set it */
+ dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD);
+ }
+ /*
+ * Workaround for avoiding TX arbitration lost in case I2C
+ * slave pulls SDA down "too quickly" after falling egde of
+ * SCL by enabling non-zero SDA RX hold. Specification says it
+ * extends incoming SDA low to high transition while SCL is
+ * high but it apprears to help also above issue.
+ */
+ if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
+ dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+ dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
+ } else {
+ dev_warn(dev->dev,
+ "Hardware too old to adjust SDA hold time.\n");
+ }
+
+ i2c_dw_configure_fifo_master(dev);
+ i2c_dw_release_lock(dev);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_init);
+
+static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
+{
+ struct i2c_msg *msgs = dev->msgs;
+ u32 ic_con, ic_tar = 0;
+
+ /* Disable the adapter */
+ __i2c_dw_enable_and_wait(dev, false);
+
+ /* 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;
+ /*
+ * If I2C_DYNAMIC_TAR_UPDATE is set, the 10-bit addressing
+ * mode has to be enabled via bit 12 of IC_TAR register.
+ * We set it always as I2C_DYNAMIC_TAR_UPDATE can't be
+ * detected from registers.
+ */
+ ic_tar = DW_IC_TAR_10BITADDR_MASTER;
+ } else {
+ ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
+ }
+
+ dw_writel(dev, ic_con, DW_IC_CON);
+
+ /*
+ * Set the slave (target) address and enable 10-bit addressing mode
+ * if applicable.
+ */
+ dw_writel(dev, msgs[dev->msg_write_idx].addr | ic_tar, DW_IC_TAR);
+
+ /* Enforce disabled interrupts (due to HW issues) */
+ i2c_dw_disable_int(dev);
+
+ /* Enable the adapter */
+ __i2c_dw_enable(dev, true);
+
+ /* Clear and enable interrupts */
+ dw_readl(dev, DW_IC_CLR_INTR);
+ dw_writel(dev, DW_IC_INTR_MASTER_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.
+ */
+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;
+ bool need_restart = false;
+
+ intr_mask = DW_IC_INTR_MASTER_MASK;
+
+ for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) {
+ u32 flags = msgs[dev->msg_write_idx].flags;
+
+ /*
+ * 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;
+
+ /* If both IC_EMPTYFIFO_HOLD_MASTER_EN and
+ * IC_RESTART_EN are set, we must manually
+ * set restart bit between messages.
+ */
+ if ((dev->master_cfg & DW_IC_CON_RESTART_EN) &&
+ (dev->msg_write_idx > 0))
+ need_restart = true;
+ }
+
+ 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) {
+ u32 cmd = 0;
+
+ /*
+ * If IC_EMPTYFIFO_HOLD_MASTER_EN is set we must
+ * manually set the stop bit. However, it cannot be
+ * detected from the registers so we set it always
+ * when writing/reading the last byte.
+ */
+
+ /*
+ * i2c-core always sets the buffer length of
+ * I2C_FUNC_SMBUS_BLOCK_DATA to 1. The length will
+ * be adjusted when receiving the first byte.
+ * Thus we can't stop the transaction here.
+ */
+ if (dev->msg_write_idx == dev->msgs_num - 1 &&
+ buf_len == 1 && !(flags & I2C_M_RECV_LEN))
+ cmd |= BIT(9);
+
+ if (need_restart) {
+ cmd |= BIT(10);
+ need_restart = false;
+ }
+
+ if (msgs[dev->msg_write_idx].flags & I2C_M_RD) {
+
+ /* Avoid rx buffer overrun */
+ if (dev->rx_outstanding >= dev->rx_fifo_depth)
+ break;
+
+ dw_writel(dev, cmd | 0x100, DW_IC_DATA_CMD);
+ rx_limit--;
+ dev->rx_outstanding++;
+ } else
+ dw_writel(dev, cmd | *buf++, DW_IC_DATA_CMD);
+ tx_limit--; buf_len--;
+ }
+
+ dev->tx_buf = buf;
+ dev->tx_buf_len = buf_len;
+
+ /*
+ * Because we don't know the buffer length in the
+ * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop
+ * the transaction here.
+ */
+ if (buf_len > 0 || flags & I2C_M_RECV_LEN) {
+ /* 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 u8
+i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len)
+{
+ struct i2c_msg *msgs = dev->msgs;
+ u32 flags = msgs[dev->msg_read_idx].flags;
+
+ /*
+ * Adjust the buffer length and mask the flag
+ * after receiving the first byte.
+ */
+ len += (flags & I2C_CLIENT_PEC) ? 2 : 1;
+ dev->tx_buf_len = len - min_t(u8, len, dev->rx_outstanding);
+ msgs[dev->msg_read_idx].len = len;
+ msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN;
+
+ return len;
+}
+
+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--) {
+ u32 flags = msgs[dev->msg_read_idx].flags;
+
+ *buf = dw_readl(dev, DW_IC_DATA_CMD);
+ /* Ensure length byte is a valid value */
+ if (flags & I2C_M_RECV_LEN &&
+ *buf <= I2C_SMBUS_BLOCK_MAX && *buf > 0) {
+ len = i2c_dw_recv_len(dev, *buf);
+ }
+ buf++;
+ dev->rx_outstanding--;
+ }
+
+ 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;
+ }
+}
+
+/*
+ * 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);
+
+ pm_runtime_get_sync(dev->dev);
+
+ reinit_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;
+ dev->rx_outstanding = 0;
+
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ goto done_nolock;
+
+ 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 */
+ if (!wait_for_completion_timeout(&dev->cmd_complete, adap->timeout)) {
+ dev_err(dev->dev, "controller timed out\n");
+ /* i2c_dw_init implicitly disables the adapter */
+ i2c_dw_init(dev);
+ ret = -ETIMEDOUT;
+ goto done;
+ }
+
+ /*
+ * We must disable the adapter before returning and signaling the end
+ * of the current transfer. Otherwise the hardware might continue
+ * generating interrupts which in turn causes a race condition with
+ * the following transfer. Needs some more investigation if the
+ * additional interrupts are a hardware bug or this driver doesn't
+ * handle them correctly yet.
+ */
+ __i2c_dw_enable(dev, false);
+
+ if (dev->msg_err) {
+ ret = dev->msg_err;
+ goto done;
+ }
+
+ /* No error */
+ if (likely(!dev->cmd_err && !dev->status)) {
+ 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;
+ }
+
+ if (dev->status)
+ dev_err(dev->dev,
+ "transfer terminated early - interrupt latency too high?\n");
+
+ ret = -EIO;
+
+done:
+ i2c_dw_release_lock(dev);
+
+done_nolock:
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
+ return ret;
+}
+
+static const struct i2c_algorithm i2c_dw_algo = {
+ .master_xfer = i2c_dw_xfer,
+ .functionality = i2c_dw_func,
+};
+
+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 master interrupt
+ * occurs.
+ */
+static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
+{
+ u32 stat;
+
+ 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);
+ else if (unlikely(dev->flags & ACCESS_INTR_MASK)) {
+ /* Workaround to trigger pending interrupt */
+ stat = dw_readl(dev, DW_IC_INTR_MASK);
+ i2c_dw_disable_int(dev);
+ dw_writel(dev, stat, DW_IC_INTR_MASK);
+ }
+
+ return 0;
+}
+
+static 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, "enabled=%#x stat=%#x\n", enabled, stat);
+ if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY))
+ return IRQ_NONE;
+
+ i2c_dw_irq_handler_master(dev);
+
+ return IRQ_HANDLED;
+}
+
+int i2c_dw_probe(struct dw_i2c_dev *dev)
+{
+ struct i2c_adapter *adap = &dev->adapter;
+ unsigned long irq_flags;
+ int ret;
+
+ init_completion(&dev->cmd_complete);
+
+ dev->init = i2c_dw_init;
+ dev->disable = i2c_dw_disable;
+ dev->disable_int = i2c_dw_disable_int;
+
+ ret = dev->init(dev);
+ if (ret)
+ return ret;
+
+ snprintf(adap->name, sizeof(adap->name),
+ "Synopsys DesignWare I2C adapter");
+ adap->retries = 3;
+ adap->algo = &i2c_dw_algo;
+ adap->dev.parent = dev->dev;
+ i2c_set_adapdata(adap, dev);
+
+ if (dev->pm_disabled) {
+ dev_pm_syscore_device(dev->dev, true);
+ irq_flags = IRQF_NO_SUSPEND;
+ } else {
+ irq_flags = IRQF_SHARED | IRQF_COND_SUSPEND;
+ }
+
+ i2c_dw_disable_int(dev);
+ ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, irq_flags,
+ dev_name(dev->dev), dev);
+ if (ret) {
+ dev_err(dev->dev, "failure requesting irq %i: %d\n",
+ dev->irq, ret);
+ return ret;
+ }
+
+ /*
+ * Increment PM usage count during adapter registration in order to
+ * avoid possible spurious runtime suspend when adapter device is
+ * registered to the device core and immediate resume in case bus has
+ * registered I2C slaves that do I2C transfers in their probe.
+ */
+ pm_runtime_get_noresume(dev->dev);
+ ret = i2c_add_numbered_adapter(adap);
+ if (ret)
+ dev_err(dev->dev, "failure adding adapter: %d\n", ret);
+ pm_runtime_put_noidle(dev->dev);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(i2c_dw_probe);
+
+MODULE_DESCRIPTION("Synopsys DesignWare I2C bus master adapter");
+MODULE_LICENSE("GPL");