Re: [PATCH v4 2/5] i2c: designware: Master mode as separated driver
From: Andy Shevchenko
Date: Wed Dec 07 2016 - 14:05:11 EST
On Wed, 2016-12-07 at 17:55 +0000, Luis Oliveira wrote:
> - The functions related to I2C master mode of operation were moved
> Â to a single file: i2c-designware-master.c
> - Common functions were moved into i2c-designware-common.c
> - Common definitions were moved into i2c-designware-core.h (were in
> core.c)
>
Yeah, there are some places that might be cleaned up but it came from
the original and could be done in the future.
Acked-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Signed-off-by: Luis Oliveira <lolivei@xxxxxxxxxxxx>
> ---
> Changes V3->V4: (Andy Shevchenko)
> - The name of the i2c-designware-src.c was changed to i2c-designware-
> common.c
> Â as suggested by Andy.
>
> Âdrivers/i2c/busses/MakefileÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ|ÂÂÂ1 +
> Âdrivers/i2c/busses/i2c-designware-common.cÂÂÂÂÂÂÂÂÂ| 252
> +++++++++++++++
> Âdrivers/i2c/busses/i2c-designware-core.hÂÂÂÂÂÂÂÂÂÂÂ| 131 ++++++++
> Â...c-designware-core.c => i2c-designware-master.c} | 347 +-----------
> ---------
> Â4 files changed, 390 insertions(+), 341 deletions(-)
> Âcreate mode 100644 drivers/i2c/busses/i2c-designware-common.c
> Ârename drivers/i2c/busses/{i2c-designware-core.c => i2c-designware-
> master.c} (66%)
>
> diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
> index 1c1bac87a9db..4f8f6a2b9346 100644
> --- a/drivers/i2c/busses/Makefile
> +++ b/drivers/i2c/busses/Makefile
> @@ -40,6 +40,7 @@ obj-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-
> gpio.o
> Âobj-$(CONFIG_I2C_CPM) += i2c-cpm.o
> Âobj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o
> Âobj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o
> +i2c-designware-core-objs := i2c-designware-common.o i2c-designware-
> master.o
> Âobj-$(CONFIG_I2C_DESIGNWARE_PLATFORM) += i2c-designware-
> platform.o
> Âi2c-designware-platform-objs := i2c-designware-platdrv.o
> Âi2c-designware-platform-$(CONFIG_I2C_DESIGNWARE_BAYTRAIL) += i2c-
> designware-baytrail.o
> diff --git a/drivers/i2c/busses/i2c-designware-common.c
> b/drivers/i2c/busses/i2c-designware-common.c
> new file mode 100644
> index 000000000000..6afd2ff5d73f
> --- /dev/null
> +++ b/drivers/i2c/busses/i2c-designware-common.c
> @@ -0,0 +1,252 @@
> +/*
> + * 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.ÂÂSee 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"
> +
> +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;
> +
> + 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;
> +}
> +
> +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);
> + }
> +}
> +
> +u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int
> offset)
> +{
> + /*
> + Â* DesignWare I2C core doesn't seem to have solid strategy to
> meet
> + Â* the tHD;STA timing spec.ÂÂConfiguring _HCNT based on tHIGH
> spec
> + Â* will result in violation of the tHD;STA spec.
> + Â*/
> + if (cond)
> + /*
> + Â* Conditional expression:
> + Â*
> + Â*ÂÂÂIC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH
> + Â*
> + Â* This is based on the DW manuals, and represents an
> ideal
> + Â* configuration.ÂÂThe resulting I2C bus speed will
> be
> + Â* faster than any of the others.
> + Â*
> + Â* If your hardware is free from tHD;STA issue, try
> this one.
> + Â*/
> + return (ic_clk * tSYMBOL + 500000) / 1000000 - 8 +
> offset;
> + else
> + /*
> + Â* Conditional expression:
> + Â*
> + Â*ÂÂÂIC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf)
> + Â*
> + Â* This is just experimental rule; the tHD;STA period
> turned
> + Â* out to be proportinal to (_HCNT + 3).ÂÂWith this
> setting,
> + Â* we could meet both tHIGH and tHD;STA timing specs.
> + Â*
> + Â* If unsure, you'd better to take this alternative.
> + Â*
> + Â* The reason why we need to take into account "tf"
> here,
> + Â* is the same as described in i2c_dw_scl_lcnt().
> + Â*/
> + return (ic_clk * (tSYMBOL + tf) + 500000) / 1000000
> + - 3 + offset;
> +}
> +
> +u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
> +{
> + /*
> + Â* Conditional expression:
> + Â*
> + Â*ÂÂÂIC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf)
> + Â*
> + Â* DW I2C core starts counting the SCL CNTs for the LOW
> period
> + Â* of the SCL clock (tLOW) as soon as it pulls the SCL line.
> + Â* In order to meet the tLOW timing spec, we need to take
> into
> + Â* account the fall time of SCL signal (tf).ÂÂDefault tf
> value
> + Â* should be 0.3 us, for safety.
> + Â*/
> + return ((ic_clk * (tLOW + tf) + 500000) / 1000000) - 1 +
> offset;
> +}
> +
> +void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable)
> +{
> + dw_writel(dev, enable, DW_IC_ENABLE);
> +}
> +
> +void __i2c_dw_enable_and_wait(struct dw_i2c_dev *dev, bool enable)
> +{
> + int timeout = 100;
> +
> + do {
> + __i2c_dw_enable(dev, enable);
> + if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) ==
> enable)
> + return;
> +
> + /*
> + Â* Wait 10 times the signaling period of the highest
> I2C
> + Â* transfer supported by the driver (for 400KHz this
> is
> + Â* 25us) as described in the DesignWare I2C databook.
> + Â*/
> + usleep_range(25, 250);
> + } while (timeout--);
> +
> + dev_warn(dev->dev, "timeout in %sabling adapter\n",
> + Âenable ? "en" : "dis");
> +}
> +
> +unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
> +{
> + /*
> + Â* Clock is not necessary if we got LCNT/HCNT values directly
> from
> + Â* the platform code.
> + Â*/
> + if (WARN_ON_ONCE(!dev->get_clk_rate_khz))
> + return 0;
> + return dev->get_clk_rate_khz(dev);
> +}
> +
> +int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
> +{
> + int ret;
> +
> + if (!dev->acquire_lock)
> + return 0;
> +
> + ret = dev->acquire_lock(dev);
> + if (!ret)
> + return 0;
> +
> + dev_err(dev->dev, "couldn't acquire bus ownership\n");
> +
> + return ret;
> +}
> +
> +void i2c_dw_release_lock(struct dw_i2c_dev *dev)
> +{
> + if (dev->release_lock)
> + dev->release_lock(dev);
> +}
> +
> +/*
> + * Waiting for bus not busy
> + */
> +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;
> +}
> +
> +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;
> +}
> +
> +u32 i2c_dw_func(struct i2c_adapter *adap)
> +{
> + struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
> + return dev->functionality;
> +}
> +
> +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/i2c/busses/i2c-designware-core.h
> b/drivers/i2c/busses/i2c-designware-core.h
> index 26250b425e2f..8bba7a37c3ce 100644
> --- a/drivers/i2c/busses/i2c-designware-core.h
> +++ b/drivers/i2c/busses/i2c-designware-core.h
> @@ -40,6 +40,124 @@
> Â#define DW_IC_CON_RESTART_EN 0x20
> Â#define DW_IC_CON_SLAVE_DISABLE 0x40
> Â
> +/*
> + * 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_HS_SCL_HCNT 0x24
> +#define DW_IC_HS_SCL_LCNT 0x28
> +#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 |
> \
> + ÂDW_IC_INTR_TX_ABRT | \
> + ÂDW_IC_INTR_STOP_DET)
> +#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MAS
> K | \
> + ÂDW_IC_INTR_TX_EMPTY)
> +#define DW_IC_STATUS_ACTIVITY 0x1
> +#define DW_IC_STATUS_TFE BIT(2)
> +#define DW_IC_STATUS_MASTER_ACTIVITY BIT(5)
> +
> +#define DW_IC_SDA_HOLD_RX_SHIFT 16
> +#define DW_IC_SDA_HOLD_RX_MASK GENMASK(23,
> DW_IC_SDA_HOLD_RX_SHIFT)
> +
> +#define DW_IC_ERR_TX_ABRT 0x1
> +
> +#define DW_IC_TAR_10BITADDR_MASTER BIT(12)
> +
> +#define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH (BIT(2) | BIT(3))
> +#define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK GENMASK(3, 2)
> +
> +/*
> + * 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_NOA
> CK | \
> + ÂDW_IC_TX_ABRT_10ADDR1_NOACK
> | \
> + ÂDW_IC_TX_ABRT_10ADDR2_NOACK
> | \
> + ÂDW_IC_TX_ABRT_TXDATA_NOACK |
> \
> + ÂDW_IC_TX_ABRT_GCALL_NOACK)
> +
> Â
> Â/**
> Â * struct dw_i2c_dev - private i2c-designware data
> @@ -132,6 +250,19 @@ struct dw_i2c_dev {
> Â#define ACCESS_16BIT 0x00000002
> Â#define ACCESS_INTR_MASK 0x00000004
> Â
> +u32 dw_readl(struct dw_i2c_dev *dev, int offset);
> +void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
> +u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int
> offset);
> +u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
> +void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable);
> +void __i2c_dw_enable_and_wait(struct dw_i2c_dev *dev, bool enable);
> +unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
> +int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
> +void i2c_dw_release_lock(struct dw_i2c_dev *dev);
> +int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev);
> +int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev);
> +u32 i2c_dw_func(struct i2c_adapter *adap);
> +
> Âextern int i2c_dw_init(struct dw_i2c_dev *dev);
> Âextern void i2c_dw_disable(struct dw_i2c_dev *dev);
> Âextern void i2c_dw_disable_int(struct dw_i2c_dev *dev);
> diff --git a/drivers/i2c/busses/i2c-designware-core.c
> b/drivers/i2c/busses/i2c-designware-master.c
> similarity index 66%
> rename from drivers/i2c/busses/i2c-designware-core.c
> rename to drivers/i2c/busses/i2c-designware-master.c
> index a51addfde565..9943addac3d7 100644
> --- a/drivers/i2c/busses/i2c-designware-core.c
> +++ b/drivers/i2c/busses/i2c-designware-master.c
> @@ -32,305 +32,18 @@
> Â#include <linux/module.h>
> Â#include "i2c-designware-core.h"
> Â
> -/*
> - * 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_HS_SCL_HCNT 0x24
> -#define DW_IC_HS_SCL_LCNT 0x28
> -#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 |
> \
> - ÂDW_IC_INTR_TX_ABRT | \
> - ÂDW_IC_INTR_STOP_DET)
> -
> -#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MAS
> K | \
> - ÂDW_IC_INTR_TX_EMPTY)
> -
> -#define DW_IC_STATUS_ACTIVITY 0x1
> -
> -#define DW_IC_SDA_HOLD_RX_SHIFT 16
> -#define DW_IC_SDA_HOLD_RX_MASK GENMASK(23,
> DW_IC_SDA_HOLD_RX_SHIFT)
> -
> -#define DW_IC_ERR_TX_ABRT 0x1
> -
> -#define DW_IC_TAR_10BITADDR_MASTER BIT(12)
> -
> -#define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH (BIT(2) | BIT(3))
> -#define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK GENMASK(3, 2)
> -
> -/*
> - * 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_NOA
> CK | \
> - ÂDW_IC_TX_ABRT_10ADDR1_NOACK
> | \
> - ÂDW_IC_TX_ABRT_10ADDR2_NOACK
> | \
> - ÂDW_IC_TX_ABRT_TXDATA_NOACK |
> \
> - ÂDW_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;
> -}
> -
> -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);
> - }
> -}
> -
> Âstatic void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev)
> Â{
> Â /* Configure Tx/Rx FIFO threshold levels */
> Â dw_writel(dev, dev->tx_fifo_depth / 2, DW_IC_TX_TL);
> Â dw_writel(dev, 0, DW_IC_RX_TL);
> Â
> - /* configure the i2c master */
> + /* configure the I2C master */
> Â dw_writel(dev, dev->master_cfg, DW_IC_CON);
> Â}
> Â
> -static u32
> -i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int
> offset)
> -{
> - /*
> - Â* DesignWare I2C core doesn't seem to have solid strategy to
> meet
> - Â* the tHD;STA timing spec.ÂÂConfiguring _HCNT based on tHIGH
> spec
> - Â* will result in violation of the tHD;STA spec.
> - Â*/
> - if (cond)
> - /*
> - Â* Conditional expression:
> - Â*
> - Â*ÂÂÂIC_[FS]S_SCL_HCNT + (1+4+3) >= IC_CLK * tHIGH
> - Â*
> - Â* This is based on the DW manuals, and represents an
> ideal
> - Â* configuration.ÂÂThe resulting I2C bus speed will
> be
> - Â* faster than any of the others.
> - Â*
> - Â* If your hardware is free from tHD;STA issue, try
> this one.
> - Â*/
> - return (ic_clk * tSYMBOL + 500000) / 1000000 - 8 +
> offset;
> - else
> - /*
> - Â* Conditional expression:
> - Â*
> - Â*ÂÂÂIC_[FS]S_SCL_HCNT + 3 >= IC_CLK * (tHD;STA + tf)
> - Â*
> - Â* This is just experimental rule; the tHD;STA period
> turned
> - Â* out to be proportinal to (_HCNT + 3).ÂÂWith this
> setting,
> - Â* we could meet both tHIGH and tHD;STA timing specs.
> - Â*
> - Â* If unsure, you'd better to take this alternative.
> - Â*
> - Â* The reason why we need to take into account "tf"
> here,
> - Â* is the same as described in i2c_dw_scl_lcnt().
> - Â*/
> - return (ic_clk * (tSYMBOL + tf) + 500000) / 1000000
> - - 3 + offset;
> -}
> -
> -static u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
> -{
> - /*
> - Â* Conditional expression:
> - Â*
> - Â*ÂÂÂIC_[FS]S_SCL_LCNT + 1 >= IC_CLK * (tLOW + tf)
> - Â*
> - Â* DW I2C core starts counting the SCL CNTs for the LOW
> period
> - Â* of the SCL clock (tLOW) as soon as it pulls the SCL line.
> - Â* In order to meet the tLOW timing spec, we need to take
> into
> - Â* account the fall time of SCL signal (tf).ÂÂDefault tf
> value
> - Â* should be 0.3 us, for safety.
> - Â*/
> - return ((ic_clk * (tLOW + tf) + 500000) / 1000000) - 1 +
> offset;
> -}
> -
> -static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable)
> -{
> - dw_writel(dev, enable, DW_IC_ENABLE);
> -}
> -
> -static void __i2c_dw_enable_and_wait(struct dw_i2c_dev *dev, bool
> enable)
> -{
> - int timeout = 100;
> -
> - do {
> - __i2c_dw_enable(dev, enable);
> - if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) ==
> enable)
> - return;
> -
> - /*
> - Â* Wait 10 times the signaling period of the highest
> I2C
> - Â* transfer supported by the driver (for 400KHz this
> is
> - Â* 25us) as described in the DesignWare I2C databook.
> - Â*/
> - usleep_range(25, 250);
> - } while (timeout--);
> -
> - dev_warn(dev->dev, "timeout in %sabling adapter\n",
> - Âenable ? "en" : "dis");
> -}
> -
> -static unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
> -{
> - /*
> - Â* Clock is not necessary if we got LCNT/HCNT values directly
> from
> - Â* the platform code.
> - Â*/
> - if (WARN_ON_ONCE(!dev->get_clk_rate_khz))
> - return 0;
> - return dev->get_clk_rate_khz(dev);
> -}
> -
> -static int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
> -{
> - int ret;
> -
> - if (!dev->acquire_lock)
> - return 0;
> -
> - ret = dev->acquire_lock(dev);
> - if (!ret)
> - return 0;
> -
> - dev_err(dev->dev, "couldn't acquire bus ownership\n");
> -
> - return ret;
> -}
> -
> -static void i2c_dw_release_lock(struct dw_i2c_dev *dev)
> -{
> - if (dev->release_lock)
> - dev->release_lock(dev);
> -}
> -
> Â/**
> - * i2c_dw_init() - initialize the designware i2c hardware
> + * i2c_dw_init() - initialize the designware i2c master hardware
> Â * @dev: device private data
> Â *
> Â * This functions configures and enables the I2C.
> @@ -462,25 +175,6 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
> Â}
> ÂEXPORT_SYMBOL_GPL(i2c_dw_init);
> Â
> -/*
> - * 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;
> -}
> -
> Âstatic void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
> Â{
> Â struct i2c_msg *msgs = dev->msgs;
> @@ -715,29 +409,6 @@ i2c_dw_read(struct dw_i2c_dev *dev)
> Â }
> Â}
> Â
> -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;
> -}
> -
> Â/*
> Â * Prepare controller for a transaction and call i2c_dw_xfer_msg
> Â */
> @@ -825,12 +496,6 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct
> i2c_msg msgs[], int num)
> Â return ret;
> Â}
> Â
> -static u32 i2c_dw_func(struct i2c_adapter *adap)
> -{
> - struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
> - return dev->functionality;
> -}
> -
> Âstatic struct i2c_algorithm i2c_dw_algo = {
> Â .master_xfer = i2c_dw_xfer,
> Â .functionality = i2c_dw_func,
> @@ -892,10 +557,10 @@ static u32 i2c_dw_read_clear_intrbits(struct
> dw_i2c_dev *dev)
> Â}
> Â
> Â/*
> - * Interrupt service routine. This gets called whenever an I2C
> interrupt
> + * Interrupt service routine. This gets called whenever an I2C master
> interrupt
> Â * occurs.
> Â */
> -int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
> +static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
> Â{
> Â u32 stat;
> Â
> @@ -940,7 +605,7 @@ int i2c_dw_irq_handler_master(struct dw_i2c_dev
> *dev)
> Âstatic irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
> Â{
> Â struct dw_i2c_dev *dev = dev_id;
> - u32 stat, enabled, mode;
> + u32 stat, enabled;
> Â
> Â enabled = dw_readl(dev, DW_IC_ENABLE);
> Â stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
> @@ -1041,5 +706,5 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
> Â}
> ÂEXPORT_SYMBOL_GPL(i2c_dw_probe);
> Â
> -MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
> +MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter master");
> ÂMODULE_LICENSE("GPL");
--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy