[PATCH v6 08/11] i2c: designware: Convert driver to using regmap API

From: Serge Semin
Date: Thu May 28 2020 - 05:33:54 EST

Seeing the DW I2C driver is using flags-based accessors with two
conditional clauses it would be better to replace them with the regmap
API IO methods and to initialize the regmap object with read/write
callbacks specific to the controller registers map implementation. This
will be also handy for the drivers with non-standard registers mapping
(like an embedded into the Baikal-T1 System Controller DW I2C block, which
glue-driver is a part of this series).

As before the driver tries to detect the mapping setup at probe stage and
creates a regmap object accordingly, which will be used by the rest of the
code to correctly access the controller registers. In two places it was
appropriate to convert the hand-written read-modify-write and
read-poll-loop design patterns to the corresponding regmap API
ready-to-use methods.

Note the regmap IO methods return value is checked only at the probe
stage. The rest of the code won't do this because basically we have
MMIO-based regmap so non of the read/write methods can fail (this also
won't be needed for the Baikal-T1-specific I2C controller).

Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
Tested-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
Acked-by: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
Cc: Alexey Malahov <Alexey.Malahov@xxxxxxxxxxxxxxxxxxxx>
Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Cc: Rob Herring <robh+dt@xxxxxxxxxx>
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxxx

---

Changelog v5:
- Keep alphabetical order of the include statements.
- Discard explicit u16-type cast in the dw_reg_write_word() method.

Changelog v6:
- Add comma in the last explicitly initialized member of the map_cfg
struct regmap_config instance.
---
drivers/i2c/busses/Kconfig | 1 +
drivers/i2c/busses/i2c-designware-common.c | 178 +++++++++++++++------
drivers/i2c/busses/i2c-designware-core.h | 22 ++-
drivers/i2c/busses/i2c-designware-master.c | 125 ++++++++-------
drivers/i2c/busses/i2c-designware-slave.c | 77 ++++-----
5 files changed, 248 insertions(+), 155 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 7cd279c36898..259e2325712a 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -526,6 +526,7 @@ config I2C_DAVINCI

config I2C_DESIGNWARE_CORE
tristate
+ select REGMAP

config I2C_DESIGNWARE_SLAVE
bool "Synopsys DesignWare Slave"
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index ed302342f8db..0b190a3c837c 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -21,6 +21,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
#include <linux/swab.h>
#include <linux/types.h>

@@ -57,66 +58,123 @@ static char *abort_sources[] = {
"incorrect slave-transmitter mode configuration",
};

-u32 dw_readl(struct dw_i2c_dev *dev, int offset)
+static int dw_reg_read(void *context, unsigned int reg, unsigned int *val)
{
- u32 value;
+ struct dw_i2c_dev *dev = context;

- if (dev->flags & ACCESS_16BIT)
- value = readw_relaxed(dev->base + offset) |
- (readw_relaxed(dev->base + offset + 2) << 16);
- else
- value = readl_relaxed(dev->base + offset);
+ *val = readl_relaxed(dev->base + reg);

- if (dev->flags & ACCESS_SWAP)
- return swab32(value);
- else
- return value;
+ return 0;
}

-void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset)
+static int dw_reg_write(void *context, unsigned int reg, unsigned int val)
{
- if (dev->flags & ACCESS_SWAP)
- b = swab32(b);
-
- if (dev->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);
- }
+ struct dw_i2c_dev *dev = context;
+
+ writel_relaxed(val, dev->base + reg);
+
+ return 0;
+}
+
+static int dw_reg_read_swab(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ *val = swab32(readl_relaxed(dev->base + reg));
+
+ return 0;
+}
+
+static int dw_reg_write_swab(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ writel_relaxed(swab32(val), dev->base + reg);
+
+ return 0;
+}
+
+static int dw_reg_read_word(void *context, unsigned int reg, unsigned int *val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ *val = readw_relaxed(dev->base + reg) |
+ (readw_relaxed(dev->base + reg + 2) << 16);
+
+ return 0;
+}
+
+static int dw_reg_write_word(void *context, unsigned int reg, unsigned int val)
+{
+ struct dw_i2c_dev *dev = context;
+
+ writew_relaxed(val, dev->base + reg);
+ writew_relaxed(val >> 16, dev->base + reg + 2);
+
+ return 0;
}

/**
- * i2c_dw_set_reg_access() - Set register access flags
+ * i2c_dw_init_regmap() - Initialize registers map
* @dev: device private data
+ * @base: Registers map base address
*
- * Autodetects needed register access mode and sets access flags accordingly.
- * This must be called before doing any other register access.
+ * Autodetects needed register access mode and creates the regmap with
+ * corresponding read/write callbacks. This must be called before doing any
+ * other register access.
*/
-int i2c_dw_set_reg_access(struct dw_i2c_dev *dev)
+int i2c_dw_init_regmap(struct dw_i2c_dev *dev)
{
+ struct regmap_config map_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .disable_locking = true,
+ .reg_read = dw_reg_read,
+ .reg_write = dw_reg_write,
+ .max_register = DW_IC_COMP_TYPE,
+ };
u32 reg;
int ret;

+ /*
+ * Skip detecting the registers map configuration if the regmap has
+ * already been provided by a higher code.
+ */
+ if (dev->map)
+ return 0;
+
ret = i2c_dw_acquire_lock(dev);
if (ret)
return ret;

- reg = dw_readl(dev, DW_IC_COMP_TYPE);
+ reg = readl(dev->base + DW_IC_COMP_TYPE);
i2c_dw_release_lock(dev);

if (reg == swab32(DW_IC_COMP_TYPE_VALUE)) {
- /* Configure register endianness access */
- dev->flags |= ACCESS_SWAP;
+ map_cfg.reg_read = dw_reg_read_swab;
+ map_cfg.reg_write = dw_reg_write_swab;
} else if (reg == (DW_IC_COMP_TYPE_VALUE & 0x0000ffff)) {
- /* Configure register access mode 16bit */
- dev->flags |= ACCESS_16BIT;
+ map_cfg.reg_read = dw_reg_read_word;
+ map_cfg.reg_write = dw_reg_write_word;
} else if (reg != DW_IC_COMP_TYPE_VALUE) {
dev_err(dev->dev,
"Unknown Synopsys component type: 0x%08x\n", reg);
return -ENODEV;
}

+ /*
+ * Note we'll check the return value of the regmap IO accessors only
+ * at the probe stage. The rest of the code won't do this because
+ * basically we have MMIO-based regmap so non of the read/write methods
+ * can fail.
+ */
+ dev->map = devm_regmap_init(dev->dev, NULL, dev, &map_cfg);
+ if (IS_ERR(dev->map)) {
+ dev_err(dev->dev, "Failed to init the registers map\n");
+ return PTR_ERR(dev->map);
+ }
+
return 0;
}

@@ -327,11 +385,17 @@ int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
return ret;

/* Configure SDA Hold Time if required */
- reg = dw_readl(dev, DW_IC_COMP_VERSION);
+ ret = regmap_read(dev->map, DW_IC_COMP_VERSION, &reg);
+ if (ret)
+ goto err_release_lock;
+
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);
+ ret = regmap_read(dev->map, DW_IC_SDA_HOLD,
+ &dev->sda_hold_time);
+ if (ret)
+ goto err_release_lock;
}

/*
@@ -355,14 +419,16 @@ int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
dev->sda_hold_time = 0;
}

+err_release_lock:
i2c_dw_release_lock(dev);

- return 0;
+ return ret;
}

void __i2c_dw_disable(struct dw_i2c_dev *dev)
{
int timeout = 100;
+ u32 status;

do {
__i2c_dw_disable_nowait(dev);
@@ -370,7 +436,8 @@ void __i2c_dw_disable(struct dw_i2c_dev *dev)
* The enable status register may be unimplemented, but
* in that case this test reads zero and exits the loop.
*/
- if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == 0)
+ regmap_read(dev->map, DW_IC_ENABLE_STATUS, &status);
+ if ((status & 1) == 0)
return;

/*
@@ -449,22 +516,23 @@ void i2c_dw_release_lock(struct dw_i2c_dev *dev)
*/
int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
{
- int timeout = TIMEOUT;
+ u32 status;
+ int ret;

- while (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY) {
- if (timeout <= 0) {
- dev_warn(dev->dev, "timeout waiting for bus ready\n");
- i2c_recover_bus(&dev->adapter);
+ ret = regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
+ !(status & DW_IC_STATUS_ACTIVITY),
+ 1100, 20000);
+ if (ret) {
+ dev_warn(dev->dev, "timeout waiting for bus ready\n");

- if (dw_readl(dev, DW_IC_STATUS) & DW_IC_STATUS_ACTIVITY)
- return -ETIMEDOUT;
- return 0;
- }
- timeout--;
- usleep_range(1000, 1100);
+ i2c_recover_bus(&dev->adapter);
+
+ regmap_read(dev->map, DW_IC_STATUS, &status);
+ if (!(status & DW_IC_STATUS_ACTIVITY))
+ ret = 0;
}

- return 0;
+ return ret;
}

int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
@@ -490,15 +558,19 @@ int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
return -EIO;
}

-void i2c_dw_set_fifo_size(struct dw_i2c_dev *dev)
+int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev)
{
u32 param, tx_fifo_depth, rx_fifo_depth;
+ int ret;

/*
* Try to detect the FIFO depth if not set by interface driver,
* the depth could be from 2 to 256 from HW spec.
*/
- param = dw_readl(dev, DW_IC_COMP_PARAM_1);
+ ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &param);
+ if (ret)
+ return ret;
+
tx_fifo_depth = ((param >> 16) & 0xff) + 1;
rx_fifo_depth = ((param >> 8) & 0xff) + 1;
if (!dev->tx_fifo_depth) {
@@ -510,6 +582,8 @@ void i2c_dw_set_fifo_size(struct dw_i2c_dev *dev)
dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
rx_fifo_depth);
}
+
+ return 0;
}

u32 i2c_dw_func(struct i2c_adapter *adap)
@@ -521,17 +595,19 @@ u32 i2c_dw_func(struct i2c_adapter *adap)

void i2c_dw_disable(struct dw_i2c_dev *dev)
{
+ u32 dummy;
+
/* Disable controller */
__i2c_dw_disable(dev);

/* Disable all interrupts */
- dw_writel(dev, 0, DW_IC_INTR_MASK);
- dw_readl(dev, DW_IC_CLR_INTR);
+ regmap_write(dev->map, DW_IC_INTR_MASK, 0);
+ regmap_read(dev->map, DW_IC_CLR_INTR, &dummy);
}

void i2c_dw_disable_int(struct dw_i2c_dev *dev)
{
- dw_writel(dev, 0, DW_IC_INTR_MASK);
+ regmap_write(dev->map, DW_IC_INTR_MASK, 0);
}

MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core");
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index b9ef9b0deef0..f5bbe3d6bcf8 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -15,6 +15,7 @@
#include <linux/dev_printk.h>
#include <linux/errno.h>
#include <linux/i2c.h>
+#include <linux/regmap.h>
#include <linux/types.h>

#define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C | \
@@ -126,8 +127,6 @@
#define STATUS_WRITE_IN_PROGRESS 0x1
#define STATUS_READ_IN_PROGRESS 0x2

-#define TIMEOUT 20 /* ms */
-
/*
* operation modes
*/
@@ -183,7 +182,9 @@ struct reset_control;
/**
* struct dw_i2c_dev - private i2c-designware data
* @dev: driver model device node
+ * @map: IO registers map
* @base: IO registers pointer
+ * @ext: Extended IO registers pointer
* @cmd_complete: tx completion indicator
* @clk: input reference clock
* @pclk: clock required to access the registers
@@ -233,6 +234,7 @@ struct reset_control;
*/
struct dw_i2c_dev {
struct device *dev;
+ struct regmap *map;
void __iomem *base;
void __iomem *ext;
struct completion cmd_complete;
@@ -284,17 +286,13 @@ struct dw_i2c_dev {
bool suspended;
};

-#define ACCESS_SWAP 0x00000001
-#define ACCESS_16BIT 0x00000002
-#define ACCESS_INTR_MASK 0x00000004
-#define ACCESS_NO_IRQ_SUSPEND 0x00000008
+#define ACCESS_INTR_MASK 0x00000001
+#define ACCESS_NO_IRQ_SUSPEND 0x00000002

#define MODEL_MSCC_OCELOT 0x00000100
#define MODEL_MASK 0x00000f00

-u32 dw_readl(struct dw_i2c_dev *dev, int offset);
-void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
-int i2c_dw_set_reg_access(struct dw_i2c_dev *dev);
+int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
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);
int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
@@ -304,19 +302,19 @@ 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);
-void i2c_dw_set_fifo_size(struct dw_i2c_dev *dev);
+int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev);
u32 i2c_dw_func(struct i2c_adapter *adap);
void i2c_dw_disable(struct dw_i2c_dev *dev);
void i2c_dw_disable_int(struct dw_i2c_dev *dev);

static inline void __i2c_dw_enable(struct dw_i2c_dev *dev)
{
- dw_writel(dev, 1, DW_IC_ENABLE);
+ regmap_write(dev->map, DW_IC_ENABLE, 1);
}

static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev)
{
- dw_writel(dev, 0, DW_IC_ENABLE);
+ regmap_write(dev->map, DW_IC_ENABLE, 0);
}

void __i2c_dw_disable(struct dw_i2c_dev *dev);
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 95eeec53c744..2cba21b945d8 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -18,6 +18,7 @@
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
#include <linux/reset.h>

#include "i2c-designware-core.h"
@@ -25,11 +26,11 @@
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);
+ regmap_write(dev->map, DW_IC_TX_TL, dev->tx_fifo_depth / 2);
+ regmap_write(dev->map, DW_IC_RX_TL, 0);

/* Configure the I2C master */
- dw_writel(dev, dev->master_cfg, DW_IC_CON);
+ regmap_write(dev->map, DW_IC_CON, dev->master_cfg);
}

static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
@@ -44,8 +45,11 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
ret = i2c_dw_acquire_lock(dev);
if (ret)
return ret;
- comp_param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
+
+ ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, &comp_param1);
i2c_dw_release_lock(dev);
+ if (ret)
+ return ret;

/* Set standard and fast speed dividers for high/low periods */
sda_falling_time = t->sda_fall_ns ?: 300; /* ns */
@@ -187,22 +191,22 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev)
__i2c_dw_disable(dev);

/* Write standard speed timing parameters */
- dw_writel(dev, dev->ss_hcnt, DW_IC_SS_SCL_HCNT);
- dw_writel(dev, dev->ss_lcnt, DW_IC_SS_SCL_LCNT);
+ regmap_write(dev->map, DW_IC_SS_SCL_HCNT, dev->ss_hcnt);
+ regmap_write(dev->map, DW_IC_SS_SCL_LCNT, dev->ss_lcnt);

/* Write fast mode/fast mode plus timing parameters */
- dw_writel(dev, dev->fs_hcnt, DW_IC_FS_SCL_HCNT);
- dw_writel(dev, dev->fs_lcnt, DW_IC_FS_SCL_LCNT);
+ regmap_write(dev->map, DW_IC_FS_SCL_HCNT, dev->fs_hcnt);
+ regmap_write(dev->map, DW_IC_FS_SCL_LCNT, dev->fs_lcnt);

/* Write high speed timing parameters if supported */
if (dev->hs_hcnt && dev->hs_lcnt) {
- dw_writel(dev, dev->hs_hcnt, DW_IC_HS_SCL_HCNT);
- dw_writel(dev, dev->hs_lcnt, DW_IC_HS_SCL_LCNT);
+ regmap_write(dev->map, DW_IC_HS_SCL_HCNT, dev->hs_hcnt);
+ regmap_write(dev->map, DW_IC_HS_SCL_LCNT, dev->hs_lcnt);
}

/* Write SDA hold time if supported */
if (dev->sda_hold_time)
- dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
+ regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time);

i2c_dw_configure_fifo_master(dev);
i2c_dw_release_lock(dev);
@@ -213,15 +217,15 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev)
static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
{
struct i2c_msg *msgs = dev->msgs;
- u32 ic_con, ic_tar = 0;
+ u32 ic_con = 0, ic_tar = 0;
+ u32 dummy;

/* Disable the adapter */
__i2c_dw_disable(dev);

/* 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;
+ 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.
@@ -229,17 +233,17 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
* 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);
+ regmap_update_bits(dev->map, DW_IC_CON, DW_IC_CON_10BITADDR_MASTER,
+ 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);
+ regmap_write(dev->map, DW_IC_TAR,
+ msgs[dev->msg_write_idx].addr | ic_tar);

/* Enforce disabled interrupts (due to HW issues) */
i2c_dw_disable_int(dev);
@@ -248,11 +252,11 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
__i2c_dw_enable(dev);

/* Dummy read to avoid the register getting stuck on Bay Trail */
- dw_readl(dev, DW_IC_ENABLE_STATUS);
+ regmap_read(dev->map, DW_IC_ENABLE_STATUS, &dummy);

/* Clear and enable interrupts */
- dw_readl(dev, DW_IC_CLR_INTR);
- dw_writel(dev, DW_IC_INTR_MASTER_MASK, DW_IC_INTR_MASK);
+ regmap_read(dev->map, DW_IC_CLR_INTR, &dummy);
+ regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_MASTER_MASK);
}

/*
@@ -271,6 +275,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
u32 buf_len = dev->tx_buf_len;
u8 *buf = dev->tx_buf;
bool need_restart = false;
+ unsigned int flr;

intr_mask = DW_IC_INTR_MASTER_MASK;

@@ -303,8 +308,11 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
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);
+ regmap_read(dev->map, DW_IC_TXFLR, &flr);
+ tx_limit = dev->tx_fifo_depth - flr;
+
+ regmap_read(dev->map, DW_IC_RXFLR, &flr);
+ rx_limit = dev->rx_fifo_depth - flr;

while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) {
u32 cmd = 0;
@@ -337,11 +345,14 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
if (dev->rx_outstanding >= dev->rx_fifo_depth)
break;

- dw_writel(dev, cmd | 0x100, DW_IC_DATA_CMD);
+ regmap_write(dev->map, DW_IC_DATA_CMD,
+ cmd | 0x100);
rx_limit--;
dev->rx_outstanding++;
- } else
- dw_writel(dev, cmd | *buf++, DW_IC_DATA_CMD);
+ } else {
+ regmap_write(dev->map, DW_IC_DATA_CMD,
+ cmd | *buf++);
+ }
tx_limit--; buf_len--;
}

@@ -371,7 +382,7 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
if (dev->msg_err)
intr_mask = 0;

- dw_writel(dev, intr_mask, DW_IC_INTR_MASK);
+ regmap_write(dev->map, DW_IC_INTR_MASK, intr_mask);
}

static u8
@@ -399,7 +410,7 @@ i2c_dw_read(struct dw_i2c_dev *dev)
int rx_valid;

for (; dev->msg_read_idx < dev->msgs_num; dev->msg_read_idx++) {
- u32 len;
+ u32 len, tmp;
u8 *buf;

if (!(msgs[dev->msg_read_idx].flags & I2C_M_RD))
@@ -413,18 +424,18 @@ i2c_dw_read(struct dw_i2c_dev *dev)
buf = dev->rx_buf;
}

- rx_valid = dw_readl(dev, DW_IC_RXFLR);
+ regmap_read(dev->map, DW_IC_RXFLR, &rx_valid);

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);
+ regmap_read(dev->map, DW_IC_DATA_CMD, &tmp);
/* 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);
+ tmp <= I2C_SMBUS_BLOCK_MAX && tmp > 0) {
+ len = i2c_dw_recv_len(dev, tmp);
}
- buf++;
+ *buf++ = tmp;
dev->rx_outstanding--;
}

@@ -542,7 +553,7 @@ static const struct i2c_adapter_quirks i2c_dw_quirks = {

static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
{
- u32 stat;
+ u32 stat, dummy;

/*
* The IC_INTR_STAT register just indicates "enabled" interrupts.
@@ -550,47 +561,47 @@ static u32 i2c_dw_read_clear_intrbits(struct dw_i2c_dev *dev)
* in the IC_RAW_INTR_STAT register.
*
* That is,
- * stat = dw_readl(IC_INTR_STAT);
+ * stat = readl(IC_INTR_STAT);
* equals to,
- * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK);
+ * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK);
*
* The raw version might be useful for debugging purposes.
*/
- stat = dw_readl(dev, DW_IC_INTR_STAT);
+ regmap_read(dev->map, DW_IC_INTR_STAT, &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).
+ * readl(IC_INTR_STAT) to 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);
+ regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy);
if (stat & DW_IC_INTR_RX_OVER)
- dw_readl(dev, DW_IC_CLR_RX_OVER);
+ regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy);
if (stat & DW_IC_INTR_TX_OVER)
- dw_readl(dev, DW_IC_CLR_TX_OVER);
+ regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy);
if (stat & DW_IC_INTR_RD_REQ)
- dw_readl(dev, DW_IC_CLR_RD_REQ);
+ regmap_read(dev->map, DW_IC_CLR_RD_REQ, &dummy);
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);
+ regmap_read(dev->map, DW_IC_TX_ABRT_SOURCE, &dev->abort_source);
+ regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy);
}
if (stat & DW_IC_INTR_RX_DONE)
- dw_readl(dev, DW_IC_CLR_RX_DONE);
+ regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy);
if (stat & DW_IC_INTR_ACTIVITY)
- dw_readl(dev, DW_IC_CLR_ACTIVITY);
+ regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy);
if (stat & DW_IC_INTR_STOP_DET)
- dw_readl(dev, DW_IC_CLR_STOP_DET);
+ regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy);
if (stat & DW_IC_INTR_START_DET)
- dw_readl(dev, DW_IC_CLR_START_DET);
+ regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy);
if (stat & DW_IC_INTR_GEN_CALL)
- dw_readl(dev, DW_IC_CLR_GEN_CALL);
+ regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy);

return stat;
}
@@ -612,7 +623,7 @@ static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
* 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);
+ regmap_write(dev->map, DW_IC_INTR_MASK, 0);
goto tx_aborted;
}

@@ -633,9 +644,9 @@ static int i2c_dw_irq_handler_master(struct dw_i2c_dev *dev)
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);
+ regmap_read(dev->map, DW_IC_INTR_MASK, &stat);
i2c_dw_disable_int(dev);
- dw_writel(dev, stat, DW_IC_INTR_MASK);
+ regmap_write(dev->map, DW_IC_INTR_MASK, stat);
}

return 0;
@@ -646,8 +657,8 @@ 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);
+ regmap_read(dev->map, DW_IC_ENABLE, &enabled);
+ regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &stat);
dev_dbg(dev->dev, "enabled=%#x stat=%#x\n", enabled, stat);
if (!enabled || !(stat & ~DW_IC_INTR_ACTIVITY))
return IRQ_NONE;
@@ -739,7 +750,7 @@ int i2c_dw_probe_master(struct dw_i2c_dev *dev)
dev->disable = i2c_dw_disable;
dev->disable_int = i2c_dw_disable_int;

- ret = i2c_dw_set_reg_access(dev);
+ ret = i2c_dw_init_regmap(dev);
if (ret)
return ret;

@@ -747,7 +758,9 @@ int i2c_dw_probe_master(struct dw_i2c_dev *dev)
if (ret)
return ret;

- i2c_dw_set_fifo_size(dev);
+ ret = i2c_dw_set_fifo_size(dev);
+ if (ret)
+ return ret;

ret = dev->init(dev);
if (ret)
diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c
index 576e7af4e94b..44974b53a626 100644
--- a/drivers/i2c/busses/i2c-designware-slave.c
+++ b/drivers/i2c/busses/i2c-designware-slave.c
@@ -14,18 +14,19 @@
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
+#include <linux/regmap.h>

#include "i2c-designware-core.h"

static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev)
{
/* Configure Tx/Rx FIFO threshold levels. */
- dw_writel(dev, 0, DW_IC_TX_TL);
- dw_writel(dev, 0, DW_IC_RX_TL);
+ regmap_write(dev->map, DW_IC_TX_TL, 0);
+ regmap_write(dev->map, DW_IC_RX_TL, 0);

/* Configure the I2C slave. */
- dw_writel(dev, dev->slave_cfg, DW_IC_CON);
- dw_writel(dev, DW_IC_INTR_SLAVE_MASK, DW_IC_INTR_MASK);
+ regmap_write(dev->map, DW_IC_CON, dev->slave_cfg);
+ regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_SLAVE_MASK);
}

/**
@@ -49,7 +50,7 @@ static int i2c_dw_init_slave(struct dw_i2c_dev *dev)

/* Write SDA hold time if supported */
if (dev->sda_hold_time)
- dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD);
+ regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time);

i2c_dw_configure_fifo_slave(dev);
i2c_dw_release_lock(dev);
@@ -72,7 +73,7 @@ static int i2c_dw_reg_slave(struct i2c_client *slave)
* the address to which the DW_apb_i2c responds.
*/
__i2c_dw_disable_nowait(dev);
- dw_writel(dev, slave->addr, DW_IC_SAR);
+ regmap_write(dev->map, DW_IC_SAR, slave->addr);
dev->slave = slave;

__i2c_dw_enable(dev);
@@ -103,7 +104,7 @@ static int i2c_dw_unreg_slave(struct i2c_client *slave)

static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev)
{
- u32 stat;
+ u32 stat, dummy;

/*
* The IC_INTR_STAT register just indicates "enabled" interrupts.
@@ -111,39 +112,39 @@ static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev)
* in the IC_RAW_INTR_STAT register.
*
* That is,
- * stat = dw_readl(IC_INTR_STAT);
+ * stat = readl(IC_INTR_STAT);
* equals to,
- * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK);
+ * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK);
*
* The raw version might be useful for debugging purposes.
*/
- stat = dw_readl(dev, DW_IC_INTR_STAT);
+ regmap_read(dev->map, DW_IC_INTR_STAT, &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).
+ * readl(IC_INTR_STAT) to readl(IC_CLR_INTR).
*
* Instead, use the separately-prepared IC_CLR_* registers.
*/
if (stat & DW_IC_INTR_TX_ABRT)
- dw_readl(dev, DW_IC_CLR_TX_ABRT);
+ regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy);
if (stat & DW_IC_INTR_RX_UNDER)
- dw_readl(dev, DW_IC_CLR_RX_UNDER);
+ regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy);
if (stat & DW_IC_INTR_RX_OVER)
- dw_readl(dev, DW_IC_CLR_RX_OVER);
+ regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy);
if (stat & DW_IC_INTR_TX_OVER)
- dw_readl(dev, DW_IC_CLR_TX_OVER);
+ regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy);
if (stat & DW_IC_INTR_RX_DONE)
- dw_readl(dev, DW_IC_CLR_RX_DONE);
+ regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy);
if (stat & DW_IC_INTR_ACTIVITY)
- dw_readl(dev, DW_IC_CLR_ACTIVITY);
+ regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy);
if (stat & DW_IC_INTR_STOP_DET)
- dw_readl(dev, DW_IC_CLR_STOP_DET);
+ regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy);
if (stat & DW_IC_INTR_START_DET)
- dw_readl(dev, DW_IC_CLR_START_DET);
+ regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy);
if (stat & DW_IC_INTR_GEN_CALL)
- dw_readl(dev, DW_IC_CLR_GEN_CALL);
+ regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy);

return stat;
}
@@ -155,14 +156,14 @@ static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev)

static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
{
- u32 raw_stat, stat, enabled;
- u8 val, slave_activity;
+ u32 raw_stat, stat, enabled, tmp;
+ u8 val = 0, slave_activity;

- stat = dw_readl(dev, DW_IC_INTR_STAT);
- enabled = dw_readl(dev, DW_IC_ENABLE);
- raw_stat = dw_readl(dev, DW_IC_RAW_INTR_STAT);
- slave_activity = ((dw_readl(dev, DW_IC_STATUS) &
- DW_IC_STATUS_SLAVE_ACTIVITY) >> 6);
+ regmap_read(dev->map, DW_IC_INTR_STAT, &stat);
+ regmap_read(dev->map, DW_IC_ENABLE, &enabled);
+ regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat);
+ regmap_read(dev->map, DW_IC_STATUS, &tmp);
+ slave_activity = ((tmp & DW_IC_STATUS_SLAVE_ACTIVITY) >> 6);

if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave)
return 0;
@@ -177,7 +178,8 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
if (stat & DW_IC_INTR_RD_REQ) {
if (slave_activity) {
if (stat & DW_IC_INTR_RX_FULL) {
- val = dw_readl(dev, DW_IC_DATA_CMD);
+ regmap_read(dev->map, DW_IC_DATA_CMD, &tmp);
+ val = tmp;

if (!i2c_slave_event(dev->slave,
I2C_SLAVE_WRITE_RECEIVED,
@@ -185,24 +187,24 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
dev_vdbg(dev->dev, "Byte %X acked!",
val);
}
- dw_readl(dev, DW_IC_CLR_RD_REQ);
+ regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);
stat = i2c_dw_read_clear_intrbits_slave(dev);
} else {
- dw_readl(dev, DW_IC_CLR_RD_REQ);
- dw_readl(dev, DW_IC_CLR_RX_UNDER);
+ regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);
+ regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &tmp);
stat = i2c_dw_read_clear_intrbits_slave(dev);
}
if (!i2c_slave_event(dev->slave,
I2C_SLAVE_READ_REQUESTED,
&val))
- dw_writel(dev, val, DW_IC_DATA_CMD);
+ regmap_write(dev->map, DW_IC_DATA_CMD, val);
}
}

if (stat & DW_IC_INTR_RX_DONE) {
if (!i2c_slave_event(dev->slave, I2C_SLAVE_READ_PROCESSED,
&val))
- dw_readl(dev, DW_IC_CLR_RX_DONE);
+ regmap_read(dev->map, DW_IC_CLR_RX_DONE, &tmp);

i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val);
stat = i2c_dw_read_clear_intrbits_slave(dev);
@@ -210,7 +212,8 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev)
}

if (stat & DW_IC_INTR_RX_FULL) {
- val = dw_readl(dev, DW_IC_DATA_CMD);
+ regmap_read(dev->map, DW_IC_DATA_CMD, &tmp);
+ val = tmp;
if (!i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED,
&val))
dev_vdbg(dev->dev, "Byte %X acked!", val);
@@ -263,7 +266,7 @@ int i2c_dw_probe_slave(struct dw_i2c_dev *dev)
dev->disable = i2c_dw_disable;
dev->disable_int = i2c_dw_disable_int;

- ret = i2c_dw_set_reg_access(dev);
+ ret = i2c_dw_init_regmap(dev);
if (ret)
return ret;

@@ -271,7 +274,9 @@ int i2c_dw_probe_slave(struct dw_i2c_dev *dev)
if (ret)
return ret;

- i2c_dw_set_fifo_size(dev);
+ ret = i2c_dw_set_fifo_size(dev);
+ if (ret)
+ return ret;

ret = dev->init(dev);
if (ret)
--
2.26.2