| /* | |
| * 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. | |
| */ | |
| static int i2c_dw_init_master(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; | |
| } | |
| 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_master(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_master; | |
| 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"); |