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Release 4.7 drivers/i2c/busses/i2c-designware-core.c

/*
 * 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/export.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 <linux/module.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_SDA_HOLD		0x7c

#define DW_IC_TX_ABRT_SOURCE	0x80

#define DW_IC_ENABLE_STATUS	0x9c

#define DW_IC_COMP_PARAM_1	0xf4

#define DW_IC_COMP_VERSION	0xf8

#define DW_IC_SDA_HOLD_MIN_VERS	0x3131312A

#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


#define DW_IC_TAR_10BITADDR_MASTER BIT(12)

/*
 * 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",
};


static u32 dw_readl(struct dw_i2c_dev *dev, int offset) { u32 value; if (dev->accessor_flags & ACCESS_16BIT) value = readw_relaxed(dev->base + offset) | (readw_relaxed(dev->base + offset + 2) << 16); else value = readl_relaxed(dev->base + offset); if (dev->accessor_flags & ACCESS_SWAP) return swab32(value); else return value; }

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jisheng zhangjisheng zhang33.70%120.00%
jarkko nikulajarkko nikula11.23%120.00%
Total81100.00%5100.00%


static void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset) { if (dev->accessor_flags & ACCESS_SWAP) b = swab32(b); if (dev->accessor_flags & ACCESS_16BIT) { writew_relaxed((u16)b, dev->base + offset); writew_relaxed((u16)(b >> 16), dev->base + offset + 2); } else { writel_relaxed(b, dev->base + offset); } }

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jarkko nikulajarkko nikula11.11%120.00%
Total90100.00%5100.00%


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 + 500000) / 1000000 - 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) + 500000) / 1000000 - 3 + offset; }

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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) + 500000) / 1000000) - 1 + offset; }

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static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable) { int timeout = 100; do { dw_writel(dev, enable, DW_IC_ENABLE); if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable) return; /* * Wait 10 times the signaling period of the highest I2C * transfer supported by the driver (for 400KHz this is * 25us) as described in the DesignWare I2C databook. */ usleep_range(25, 250); } while (timeout--); dev_warn(dev->dev, "timeout in %sabling adapter\n", enable ? "en" : "dis"); }

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static unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev) { /* * Clock is not necessary if we got LCNT/HCNT values directly from * the platform code. */ if (WARN_ON_ONCE(!dev->get_clk_rate_khz)) return 0; return dev->get_clk_rate_khz(dev); }

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/** * 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; u32 sda_falling_time, scl_falling_time; int ret; if (dev->acquire_lock) { ret = dev->acquire_lock(dev); if (ret) { dev_err(dev->dev, "couldn't acquire bus ownership\n"); return ret; } } reg = dw_readl(dev, DW_IC_COMP_TYPE); if (reg == ___constant_swab32(DW_IC_COMP_TYPE_VALUE)) { /* Configure register endianess access */ dev->accessor_flags |= ACCESS_SWAP; } else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) { /* Configure register access mode 16bit */ dev->accessor_flags |= ACCESS_16BIT; } else if (reg != DW_IC_COMP_TYPE_VALUE) { dev_err(dev->dev, "Unknown Synopsys component type: " "0x%08x\n", reg); if (dev->release_lock) dev->release_lock(dev); return -ENODEV; } /* Disable the adapter */ __i2c_dw_enable(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 */ 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); /* Configure SDA Hold Time if required */ if (dev->sda_hold_time) { reg = dw_readl(dev, DW_IC_COMP_VERSION); if (reg >= DW_IC_SDA_HOLD_MIN_VERS) dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); else dev_warn(dev->dev, "Hardware too old to adjust SDA hold time."); } /* 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); if (dev->release_lock) dev->release_lock(dev); return 0; }

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jarkko nikulajarkko nikula5411.56%16.67%
christian ruppertchristian ruppert459.64%16.67%
baruch siachbaruch siach428.99%16.67%
romain baeriswylromain baeriswyl337.07%16.67%
jean-hugues deschenesjean-hugues deschenes234.93%16.67%
stefan roesestefan roese224.71%16.67%
suravee suthikulpanitsuravee suthikulpanit163.43%16.67%
mika westerbergmika westerberg40.86%213.33%
andrew jacksonandrew jackson20.43%16.67%
Total467100.00%15100.00%

EXPORT_SYMBOL_GPL(i2c_dw_init); /* * 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--; usleep_range(1000, 1100); } return 0; }

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jean-hugues deschenesjean-hugues deschenes23.17%133.33%
Total63100.00%3100.00%


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(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_DEFAULT_MASK, DW_IC_INTR_MASK); }

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shinya kuribayashishinya kuribayashi107.35%436.36%
mika westerbergmika westerberg96.62%218.18%
wenkai duwenkai du64.41%19.09%
jarkko nikulajarkko nikula32.21%19.09%
Total136100.00%11100.00%

/* * 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_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; /* 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. */ if (dev->msg_write_idx == dev->msgs_num - 1 && buf_len == 1) 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 (rx_limit - dev->rx_outstanding <= 0) 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; 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); }

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mika westerbergmika westerberg337.59%16.67%
josef ahmadjosef ahmad173.91%16.67%
jean-hugues deschenesjean-hugues deschenes132.99%16.67%
jean delvarejean delvare10.23%16.67%
Total435100.00%15100.00%


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); 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; } }

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jean-hugues deschenesjean-hugues deschenes42.06%114.29%
Total194100.00%7100.00%


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; }

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Total109100.00%3100.00%

/* * 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; if (dev->acquire_lock) { ret = dev->acquire_lock(dev); if (ret) { dev_err(dev->dev, "couldn't acquire bus ownership\n"); 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, HZ)) { 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)) { 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: if (dev->release_lock) dev->release_lock(dev); done_nolock: pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
baruch siachbaruch siach20665.40%215.38%
david boxdavid box5015.87%17.69%
shinya kuribayashishinya kuribayashi175.40%215.38%
dirk brandewiedirk brandewie134.13%17.69%
mika westerbergmika westerberg92.86%215.38%
christian ruppertchristian ruppert82.54%17.69%
josef ahmadjosef ahmad61.90%17.69%
nicholas mc guirenicholas mc guire30.95%17.69%
wolfram sangwolfram sang20.63%17.69%
jarkko nikulajarkko nikula10.32%17.69%
Total315100.00%13100.00%


static u32 i2c_dw_func(struct i2c_adapter *adap) { struct dw_i2c_dev *dev = i2c_get_adapdata(adap); return dev->functionality; }

Contributors

PersonTokensPropCommitsCommitProp
dirk brandewiedirk brandewie1350.00%133.33%
baruch siachbaruch siach1246.15%133.33%
jarkko nikulajarkko nikula13.85%133.33%
Total26100.00%3100.00%

static 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; }

Contributors

PersonTokensPropCommitsCommitProp
shinya kuribayashishinya kuribayashi14684.88%133.33%
jean-hugues deschenesjean-hugues deschenes2413.95%133.33%
dirk brandewiedirk brandewie21.16%133.33%
Total172100.00%3100.00%

/* * 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, enabled; enabled = dw_readl(dev, DW_IC_ENABLE); stat = dw_readl(dev, DW_IC_RAW_INTR_STAT); dev_dbg(dev->dev, "%s: enabled=%#x stat=%#x\n", __func__, 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); else if (unlikely(dev->accessor_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 IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
baruch siachbaruch siach9345.59%19.09%
dirk brandewiedirk brandewie3919.12%19.09%
xiangliang yuxiangliang yu3818.63%19.09%
shinya kuribayashishinya kuribayashi2914.22%545.45%
jean-hugues deschenesjean-hugues deschenes31.47%19.09%
jarkko nikulajarkko nikula20.98%218.18%
Total204100.00%11100.00%


void i2c_dw_disable(struct dw_i2c_dev *dev) { /* Disable controller */ __i2c_dw_enable(dev, false); /* Disable all interupts */ dw_writel(dev, 0, DW_IC_INTR_MASK); dw_readl(dev, DW_IC_CLR_INTR); }

Contributors

PersonTokensPropCommitsCommitProp
dirk brandewiedirk brandewie3394.29%150.00%
mika westerbergmika westerberg25.71%150.00%
Total35100.00%2100.00%

EXPORT_SYMBOL_GPL(i2c_dw_disable);
void i2c_dw_disable_int(struct dw_i2c_dev *dev) { dw_writel(dev, 0, DW_IC_INTR_MASK); }

Contributors

PersonTokensPropCommitsCommitProp
dirk brandewiedirk brandewie19100.00%1100.00%
Total19100.00%1100.00%

EXPORT_SYMBOL_GPL(i2c_dw_disable_int);
u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev) { return dw_readl(dev, DW_IC_COMP_PARAM_1); }

Contributors

PersonTokensPropCommitsCommitProp
dirk brandewiedirk brandewie18100.00%1100.00%
Total18100.00%1100.00%

EXPORT_SYMBOL_GPL(i2c_dw_read_comp_param);
int i2c_dw_probe(struct dw_i2c_dev *dev) { struct i2c_adapter *adap = &dev->adapter; int r; init_completion(&dev->cmd_complete); r = i2c_dw_init(dev); if (r) return r; 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); i2c_dw_disable_int(dev); r = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr, IRQF_SHARED | IRQF_COND_SUSPEND, dev_name(dev->dev), dev); if (r) { dev_err(dev->dev, "failure requesting irq %i: %d\n", dev->irq, r); return r; } /* * 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); r = i2c_add_numbered_adapter(adap); if (r) dev_err(dev->dev, "failure adding adapter: %d\n", r); pm_runtime_put_noidle(dev->dev); return r; }

Contributors

PersonTokensPropCommitsCommitProp
jarkko nikulajarkko nikula18095.74%250.00%
baruch siachbaruch siach63.19%125.00%
andy shevchenkoandy shevchenko21.06%125.00%
Total188100.00%4100.00%

EXPORT_SYMBOL_GPL(i2c_dw_probe); MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
baruch siachbaruch siach92128.40%34.48%
shinya kuribayashishinya kuribayashi66820.60%2029.85%
dirk brandewiedirk brandewie50015.42%710.45%
jarkko nikulajarkko nikula2648.14%68.96%
jean-hugues deschenesjean-hugues deschenes1584.87%22.99%
mika westerbergmika westerberg1544.75%811.94%
david boxdavid box1143.52%11.49%
stefan roesestefan roese1103.39%11.49%
chiau ee chewchiau ee chew812.50%22.99%
christian ruppertchristian ruppert652.00%22.99%
suravee suthikulpanitsuravee suthikulpanit501.54%11.49%
romain baeriswylromain baeriswyl391.20%11.49%
xiangliang yuxiangliang yu381.17%11.49%
josef ahmadjosef ahmad300.93%11.49%
axel linaxel lin240.74%11.49%
wenkai duwenkai du60.19%11.49%
jisheng zhangjisheng zhang60.19%11.49%
wolfram sangwolfram sang30.09%22.99%
nicholas mc guirenicholas mc guire30.09%11.49%
andy shevchenkoandy shevchenko20.06%11.49%
tejun heotejun heo20.06%11.49%
andrew jacksonandrew jackson20.06%11.49%
akinobu mitaakinobu mita20.06%11.49%
jean delvarejean delvare10.03%11.49%
Total3243100.00%67100.00%
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