[PATCH v4 2/5] i2c: designware: Master mode as separated driver
From: Luis Oliveira
Date: Wed Dec 07 2016 - 12:58:16 EST
- The functions related to I2C master mode of operation were moved
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)
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
as suggested by Andy.
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-designware-common.c | 252 +++++++++++++++
drivers/i2c/busses/i2c-designware-core.h | 131 ++++++++
...c-designware-core.c => i2c-designware-master.c} | 347 +--------------------
4 files changed, 390 insertions(+), 341 deletions(-)
create mode 100644 drivers/i2c/busses/i2c-designware-common.c
rename 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-$(CONFIG_I2C_CBUS_GPIO) += i2c-cbus-gpio.o
obj-$(CONFIG_I2C_CPM) += i2c-cpm.o
obj-$(CONFIG_I2C_DAVINCI) += i2c-davinci.o
obj-$(CONFIG_I2C_DESIGNWARE_CORE) += i2c-designware-core.o
+i2c-designware-core-objs := i2c-designware-common.o i2c-designware-master.o
obj-$(CONFIG_I2C_DESIGNWARE_PLATFORM) += i2c-designware-platform.o
i2c-designware-platform-objs := i2c-designware-platdrv.o
i2c-designware-platform-$(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. 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"
+
+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)
+{
+ /*
+ * 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;
+}
+
+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;
+}
+
+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;
+
+ /*
+ * 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");
+}
+
+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);
+}
+
+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 @@
#define DW_IC_CON_RESTART_EN 0x20
#define DW_IC_CON_SLAVE_DISABLE 0x40
+/*
+ * 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 | \
+ DW_IC_INTR_TX_ABRT | \
+ DW_IC_INTR_STOP_DET)
+#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MASK | \
+ DW_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_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)
+
/**
* struct dw_i2c_dev - private i2c-designware data
@@ -132,6 +250,19 @@ struct dw_i2c_dev {
#define ACCESS_16BIT 0x00000002
#define ACCESS_INTR_MASK 0x00000004
+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);
+
extern int i2c_dw_init(struct dw_i2c_dev *dev);
extern void i2c_dw_disable(struct dw_i2c_dev *dev);
extern 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 @@
#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_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 | \
- DW_IC_INTR_TX_ABRT | \
- DW_IC_INTR_STOP_DET)
-
-#define DW_IC_INTR_MASTER_MASK (DW_IC_INTR_DEFAULT_MASK | \
- DW_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_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;
-}
-
-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);
- }
-}
-
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 */
+ /* configure the I2C master */
dw_writel(dev, dev->master_cfg, DW_IC_CON);
}
-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;
-}
-
-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;
-}
-
-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;
-
- /*
- * 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");
-}
-
-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);
-}
-
-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);
-}
-
/**
- * i2c_dw_init() - initialize the designware i2c hardware
+ * i2c_dw_init() - initialize the designware i2c master hardware
* @dev: device private data
*
* This functions configures and enables the I2C.
@@ -462,25 +175,6 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
}
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;
-}
-
static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
{
struct i2c_msg *msgs = dev->msgs;
@@ -715,29 +409,6 @@ i2c_dw_read(struct dw_i2c_dev *dev)
}
}
-static int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
-{
- unsigned long abort_source = dev->abort_source;
- int i;
-
- if (abort_source & DW_IC_TX_ABRT_NOACK) {
- for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources))
- dev_dbg(dev->dev,
- "%s: %s\n", __func__, abort_sources[i]);
- return -EREMOTEIO;
- }
-
- for_each_set_bit(i, &abort_source, ARRAY_SIZE(abort_sources))
- dev_err(dev->dev, "%s: %s\n", __func__, abort_sources[i]);
-
- if (abort_source & DW_IC_TX_ARB_LOST)
- return -EAGAIN;
- else if (abort_source & DW_IC_TX_ABRT_GCALL_READ)
- return -EINVAL; /* wrong msgs[] data */
- else
- return -EIO;
-}
-
/*
* Prepare controller for a transaction and call i2c_dw_xfer_msg
*/
@@ -825,12 +496,6 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
return ret;
}
-static u32 i2c_dw_func(struct i2c_adapter *adap)
-{
- struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
- return dev->functionality;
-}
-
static struct i2c_algorithm i2c_dw_algo = {
.master_xfer = i2c_dw_xfer,
.functionality = i2c_dw_func,
@@ -892,10 +557,10 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
}
/*
- * Interrupt service routine. This gets called whenever an I2C interrupt
+ * Interrupt service routine. This gets called whenever an I2C master interrupt
* occurs.
*/
-int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
+static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
{
u32 stat;
@@ -940,7 +605,7 @@ int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
{
struct dw_i2c_dev *dev = dev_id;
- u32 stat, enabled, mode;
+ u32 stat, enabled;
enabled = dw_readl(dev, DW_IC_ENABLE);
stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
@@ -1041,5 +706,5 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
}
EXPORT_SYMBOL_GPL(i2c_dw_probe);
-MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
+MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter master");
MODULE_LICENSE("GPL");
--
2.11.0