// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Synopsys DesignWare I2C adapter driver .
*
* Based on the TI DAVINCI I2C adapter driver .
*
* Copyright ( C ) 2006 Texas Instruments .
* Copyright ( C ) 2007 MontaVista Software Inc .
* Copyright ( C ) 2009 Provigent Ltd .
*/
#define DEFAULT_SYMBOL_NAMESPACE "I2C_DW_COMMON"
#include <linux/acpi.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/export.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/swab.h>
#include <linux/types.h>
#include <linux/units.h>
#include "i2c-designware-core.h"
static const char *const 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" ,
[ABRT_SLAVE_FLUSH_TXFIFO] =
"read command so flush old data in the TX FIFO" ,
[ABRT_SLAVE_ARBLOST] =
"slave lost the bus while transmitting data to a remote master" ,
[ABRT_SLAVE_RD_INTX] =
"incorrect slave-transmitter mode configuration" ,
};
static int dw_reg_read(void *context, unsigned int reg, unsigned int *val)
{
struct dw_i2c_dev *dev = context;
*val = readl(dev->base + reg);
return 0 ;
}
static int dw_reg_write(void *context, unsigned int reg, unsigned int val)
{
struct dw_i2c_dev *dev = context;
writel(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(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(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(dev->base + reg) |
(readw(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(val, dev->base + reg);
writew(val >> 16 , dev->base + reg + 2 );
return 0 ;
}
/**
* i2c_dw_init_regmap ( ) - Initialize registers map
* @ dev : device private data
*
* Autodetects needed register access mode and creates the regmap with
* corresponding read / write callbacks . This must be called before doing any
* other register access .
*
* Return : 0 on success , or negative errno otherwise .
*/
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 = readl(dev->base + DW_IC_COMP_TYPE);
i2c_dw_release_lock(dev);
if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU)
map_cfg.max_register = AMD_UCSI_INTR_REG;
if (reg == swab32(DW_IC_COMP_TYPE_VALUE)) {
map_cfg.reg_read = dw_reg_read_swab;
map_cfg.reg_write = dw_reg_write_swab;
} else if (reg == (DW_IC_COMP_TYPE_VALUE & 0 x0000ffff)) {
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 none 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 ;
}
static const u32 supported_speeds[] = {
I2C_MAX_HIGH_SPEED_MODE_FREQ,
I2C_MAX_FAST_MODE_PLUS_FREQ,
I2C_MAX_FAST_MODE_FREQ,
I2C_MAX_STANDARD_MODE_FREQ,
};
static int i2c_dw_validate_speed(struct dw_i2c_dev *dev)
{
struct i2c_timings *t = &dev->timings;
unsigned int i;
/*
* Only standard mode at 100 kHz , fast mode at 400 kHz ,
* fast mode plus at 1 MHz and high speed mode at 3 . 4 MHz are supported .
*/
for (i = 0 ; i < ARRAY_SIZE(supported_speeds); i++) {
if (t->bus_freq_hz == supported_speeds[i])
return 0 ;
}
dev_err(dev->dev,
"%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n" ,
t->bus_freq_hz);
return -EINVAL;
}
#ifdef CONFIG_OF
#include <linux/platform_device.h>
#define MSCC_ICPU_CFG_TWI_DELAY 0 x0
#define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0 )
#define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0 x4
static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
{
writel((dev->sda_hold_time << 1 ) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
return 0 ;
}
static void i2c_dw_of_configure(struct device *device)
{
struct platform_device *pdev = to_platform_device(device);
struct dw_i2c_dev *dev = dev_get_drvdata(device);
switch (dev->flags & MODEL_MASK) {
case MODEL_MSCC_OCELOT:
dev->ext = devm_platform_ioremap_resource(pdev, 1 );
if (!IS_ERR(dev->ext))
dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
break ;
default :
break ;
}
}
#else /* CONFIG_OF */
static inline void i2c_dw_of_configure(struct device *device) { }
#endif /* CONFIG_OF */
#ifdef CONFIG_ACPI
#include <linux/dmi.h>
/*
* The HCNT / LCNT information coming from ACPI should be the most accurate
* for given platform . However , some systems get it wrong . On such systems
* we get better results by calculating those based on the input clock .
*/
static const struct dmi_system_id i2c_dw_no_acpi_params[] = {
{
.ident = "Dell Inspiron 7348" ,
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc." ),
DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348" ),
},
},
{}
};
static void i2c_dw_acpi_params(struct device *device, char method[],
u16 *hcnt, u16 *lcnt, u32 *sda_hold)
{
struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
acpi_handle handle = ACPI_HANDLE(device);
union acpi_object *obj;
if (dmi_check_system(i2c_dw_no_acpi_params))
return ;
if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
return ;
obj = (union acpi_object *)buf.pointer;
if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3 ) {
const union acpi_object *objs = obj->package.elements;
*hcnt = (u16)objs[0 ].integer.value;
*lcnt = (u16)objs[1 ].integer.value;
*sda_hold = (u32)objs[2 ].integer.value;
}
kfree(buf.pointer);
}
static void i2c_dw_acpi_configure(struct device *device)
{
struct dw_i2c_dev *dev = dev_get_drvdata(device);
struct i2c_timings *t = &dev->timings;
u32 ss_ht = 0 , fp_ht = 0 , hs_ht = 0 , fs_ht = 0 ;
/*
* Try to get SDA hold time and * CNT values from an ACPI method for
* selected speed modes .
*/
i2c_dw_acpi_params(device, "SSCN" , &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
i2c_dw_acpi_params(device, "FMCN" , &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
i2c_dw_acpi_params(device, "FPCN" , &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
i2c_dw_acpi_params(device, "HSCN" , &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
switch (t->bus_freq_hz) {
case I2C_MAX_STANDARD_MODE_FREQ:
dev->sda_hold_time = ss_ht;
break ;
case I2C_MAX_FAST_MODE_PLUS_FREQ:
dev->sda_hold_time = fp_ht;
break ;
case I2C_MAX_HIGH_SPEED_MODE_FREQ:
dev->sda_hold_time = hs_ht;
break ;
case I2C_MAX_FAST_MODE_FREQ:
default :
dev->sda_hold_time = fs_ht;
break ;
}
}
static u32 i2c_dw_acpi_round_bus_speed(struct device *device)
{
u32 acpi_speed;
int i;
acpi_speed = i2c_acpi_find_bus_speed(device);
/*
* Some DSDTs use a non standard speed , round down to the lowest
* standard speed .
*/
for (i = 0 ; i < ARRAY_SIZE(supported_speeds); i++) {
if (acpi_speed >= supported_speeds[i])
return supported_speeds[i];
}
return 0 ;
}
#else /* CONFIG_ACPI */
static inline void i2c_dw_acpi_configure(struct device *device) { }
static inline u32 i2c_dw_acpi_round_bus_speed(struct device *device) { return 0 ; }
#endif /* CONFIG_ACPI */
static void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev)
{
u32 acpi_speed = i2c_dw_acpi_round_bus_speed(dev->dev);
struct i2c_timings *t = &dev->timings;
/*
* Find bus speed from the " clock - frequency " device property , ACPI
* or by using fast mode if neither is set .
*/
if (acpi_speed && t->bus_freq_hz)
t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
else if (acpi_speed || t->bus_freq_hz)
t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
else
t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
}
int i2c_dw_fw_parse_and_configure(struct dw_i2c_dev *dev)
{
struct i2c_timings *t = &dev->timings;
struct device *device = dev->dev;
struct fwnode_handle *fwnode = dev_fwnode(device);
i2c_parse_fw_timings(device, t, false );
if (device_property_read_u32(device, "snps,bus-capacitance-pf" , &dev->bus_capacitance_pF))
dev->bus_capacitance_pF = 100 ;
dev->clk_freq_optimized = device_property_read_bool(device, "snps,clk-freq-optimized" );
i2c_dw_adjust_bus_speed(dev);
if (is_of_node(fwnode))
i2c_dw_of_configure(device);
else if (is_acpi_node(fwnode))
i2c_dw_acpi_configure(device);
return i2c_dw_validate_speed(dev);
}
EXPORT_SYMBOL_GPL(i2c_dw_fw_parse_and_configure);
static u32 i2c_dw_read_scl_reg(struct dw_i2c_dev *dev, u32 reg)
{
u32 val;
int ret;
ret = i2c_dw_acquire_lock(dev);
if (ret)
return 0 ;
ret = regmap_read(dev->map, reg, &val);
i2c_dw_release_lock(dev);
return ret ? 0 : val;
}
u32 i2c_dw_scl_hcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
u32 tSYMBOL, u32 tf, int offset)
{
if (!ic_clk)
return i2c_dw_read_scl_reg(dev, reg);
/*
* 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 DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tSYMBOL + tf), MICRO) - 3 + offset;
}
u32 i2c_dw_scl_lcnt(struct dw_i2c_dev *dev, unsigned int reg, u32 ic_clk,
u32 tLOW, u32 tf, int offset)
{
if (!ic_clk)
return i2c_dw_read_scl_reg(dev, reg);
/*
* 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 DIV_ROUND_CLOSEST_ULL((u64)ic_clk * (tLOW + tf), MICRO) - 1 + offset;
}
int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
{
unsigned int reg;
int ret;
ret = i2c_dw_acquire_lock(dev);
if (ret)
return ret;
/* Configure SDA Hold Time if required */
ret = regmap_read(dev->map, DW_IC_COMP_VERSION, ®);
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 */
ret = regmap_read(dev->map, DW_IC_SDA_HOLD,
&dev->sda_hold_time);
if (ret)
goto err_release_lock;
}
/*
* Workaround for avoiding TX arbitration lost in case I2C
* slave pulls SDA down " too quickly " after falling edge of
* SCL by enabling non - zero SDA RX hold . Specification says it
* extends incoming SDA low to high transition while SCL is
* high but it appears to help also above issue .
*/
if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
dev_dbg(dev->dev, "SDA Hold Time TX:RX = %d:%d\n" ,
dev->sda_hold_time & ~(u32)DW_IC_SDA_HOLD_RX_MASK,
dev->sda_hold_time >> DW_IC_SDA_HOLD_RX_SHIFT);
} else if (dev->set_sda_hold_time) {
dev->set_sda_hold_time(dev);
} else if (dev->sda_hold_time) {
dev_warn(dev->dev,
"Hardware too old to adjust SDA hold time.\n" );
dev->sda_hold_time = 0 ;
}
err_release_lock:
i2c_dw_release_lock(dev);
return ret;
}
void __i2c_dw_disable(struct dw_i2c_dev *dev)
{
struct i2c_timings *t = &dev->timings;
unsigned int raw_intr_stats, ic_stats;
unsigned int enable;
int timeout = 100 ;
bool abort_needed;
unsigned int status;
int ret;
regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_intr_stats);
regmap_read(dev->map, DW_IC_STATUS, &ic_stats);
regmap_read(dev->map, DW_IC_ENABLE, &enable);
abort_needed = (raw_intr_stats & DW_IC_INTR_MST_ON_HOLD) ||
(ic_stats & DW_IC_STATUS_MASTER_HOLD_TX_FIFO_EMPTY);
if (abort_needed) {
if (!(enable & DW_IC_ENABLE_ENABLE)) {
regmap_write(dev->map, DW_IC_ENABLE, DW_IC_ENABLE_ENABLE);
/*
* Wait 10 times the signaling period of the highest I2C
* transfer supported by the driver ( for 400 KHz this is
* 25 us ) to ensure the I2C ENABLE bit is already set
* as described in the DesignWare I2C databook .
*/
fsleep(DIV_ROUND_CLOSEST_ULL(10 * MICRO, t->bus_freq_hz));
/* Set ENABLE bit before setting ABORT */
enable |= DW_IC_ENABLE_ENABLE;
}
regmap_write(dev->map, DW_IC_ENABLE, enable | DW_IC_ENABLE_ABORT);
ret = regmap_read_poll_timeout(dev->map, DW_IC_ENABLE, enable,
!(enable & DW_IC_ENABLE_ABORT), 10 ,
100 );
if (ret)
dev_err(dev->dev, "timeout while trying to abort current transfer\n" );
}
do {
__i2c_dw_disable_nowait(dev);
/*
* The enable status register may be unimplemented , but
* in that case this test reads zero and exits the loop .
*/
regmap_read(dev->map, DW_IC_ENABLE_STATUS, &status);
if ((status & 1 ) == 0 )
return ;
/*
* Wait 10 times the signaling period of the highest I2C
* transfer supported by the driver ( for 400 kHz this is
* 25 us ) as described in the DesignWare I2C databook .
*/
usleep_range(25 , 250 );
} while (timeout--);
dev_warn(dev->dev, "timeout in disabling adapter\n" );
}
u32 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 (!dev->get_clk_rate_khz) {
dev_dbg_once(dev->dev, "Callback get_clk_rate_khz() is not defined\n" );
return 0 ;
}
return dev->get_clk_rate_khz(dev);
}
int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare)
{
int ret;
if (prepare) {
/* Optional interface clock */
ret = clk_prepare_enable(dev->pclk);
if (ret)
return ret;
ret = clk_prepare_enable(dev->clk);
if (ret)
clk_disable_unprepare(dev->pclk);
return ret;
}
clk_disable_unprepare(dev->clk);
clk_disable_unprepare(dev->pclk);
return 0 ;
}
EXPORT_SYMBOL_GPL(i2c_dw_prepare_clk);
int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
{
int ret;
if (!dev->acquire_lock)
return 0 ;
ret = dev->acquire_lock();
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();
}
/*
* Waiting for bus not busy
*/
int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
{
unsigned int status;
int ret;
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" );
i2c_recover_bus(&dev->adapter);
regmap_read(dev->map, DW_IC_STATUS, &status);
if (!(status & DW_IC_STATUS_ACTIVITY))
ret = 0 ;
}
return ret;
}
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;
if (abort_source & DW_IC_TX_ABRT_GCALL_READ)
return -EINVAL; /* wrong msgs[] data */
return -EIO;
}
int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev)
{
u32 tx_fifo_depth, rx_fifo_depth;
unsigned int param;
int ret;
/* DW_IC_COMP_PARAM_1 not implement for IP issue */
if ((dev->flags & MODEL_MASK) == MODEL_WANGXUN_SP) {
dev->tx_fifo_depth = TXGBE_TX_FIFO_DEPTH;
dev->rx_fifo_depth = TXGBE_RX_FIFO_DEPTH;
return 0 ;
}
/*
* Try to detect the FIFO depth if not set by interface driver ,
* the depth could be from 2 to 256 from HW spec .
*/
ret = i2c_dw_acquire_lock(dev);
if (ret)
return ret;
ret = regmap_read(dev->map, DW_IC_COMP_PARAM_1, ¶m);
i2c_dw_release_lock(dev);
if (ret)
return ret;
tx_fifo_depth = ((param >> 16 ) & 0 xff) + 1 ;
rx_fifo_depth = ((param >> 8 ) & 0 xff) + 1 ;
if (!dev->tx_fifo_depth) {
dev->tx_fifo_depth = tx_fifo_depth;
dev->rx_fifo_depth = rx_fifo_depth;
} else if (tx_fifo_depth >= 2 ) {
dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
tx_fifo_depth);
dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
rx_fifo_depth);
}
return 0 ;
}
u32 i2c_dw_func(struct i2c_adapter *adap)
{
struct dw_i2c_dev *dev = i2c_get_adapdata(adap);
return dev->functionality;
}
void i2c_dw_disable(struct dw_i2c_dev *dev)
{
unsigned int dummy;
int ret;
ret = i2c_dw_acquire_lock(dev);
if (ret)
return ;
/* Disable controller */
__i2c_dw_disable(dev);
/* Disable all interrupts */
__i2c_dw_write_intr_mask(dev, 0 );
regmap_read(dev->map, DW_IC_CLR_INTR, &dummy);
i2c_dw_release_lock(dev);
}
EXPORT_SYMBOL_GPL(i2c_dw_disable);
int i2c_dw_probe(struct dw_i2c_dev *dev)
{
device_set_node(&dev->adapter.dev, dev_fwnode(dev->dev));
switch (dev->mode) {
case DW_IC_SLAVE:
return i2c_dw_probe_slave(dev);
case DW_IC_MASTER:
return i2c_dw_probe_master(dev);
default :
dev_err(dev->dev, "Wrong operation mode: %d\n" , dev->mode);
return -EINVAL;
}
}
EXPORT_SYMBOL_GPL(i2c_dw_probe);
static int i2c_dw_prepare(struct device *device)
{
/*
* If the ACPI companion device object is present for this device ,
* it may be accessed during suspend and resume of other devices via
* I2C operation regions , so tell the PM core and middle layers to
* avoid skipping system suspend / resume callbacks for it in that case .
*/
return !has_acpi_companion(device);
}
static int i2c_dw_runtime_suspend(struct device *device)
{
struct dw_i2c_dev *dev = dev_get_drvdata(device);
if (dev->shared_with_punit)
return 0 ;
i2c_dw_disable(dev);
i2c_dw_prepare_clk(dev, false );
return 0 ;
}
static int i2c_dw_suspend(struct device *device)
{
struct dw_i2c_dev *dev = dev_get_drvdata(device);
i2c_mark_adapter_suspended(&dev->adapter);
return i2c_dw_runtime_suspend(device);
}
static int i2c_dw_runtime_resume(struct device *device)
{
struct dw_i2c_dev *dev = dev_get_drvdata(device);
if (!dev->shared_with_punit)
i2c_dw_prepare_clk(dev, true );
dev->init(dev);
return 0 ;
}
static int i2c_dw_resume(struct device *device)
{
struct dw_i2c_dev *dev = dev_get_drvdata(device);
i2c_dw_runtime_resume(device);
i2c_mark_adapter_resumed(&dev->adapter);
return 0 ;
}
EXPORT_GPL_DEV_PM_OPS(i2c_dw_dev_pm_ops) = {
.prepare = pm_sleep_ptr(i2c_dw_prepare),
LATE_SYSTEM_SLEEP_PM_OPS(i2c_dw_suspend, i2c_dw_resume)
RUNTIME_PM_OPS(i2c_dw_runtime_suspend, i2c_dw_runtime_resume, NULL)
};
MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core" );
MODULE_LICENSE("GPL" );
Messung V0.5 in Prozent C=97 H=97 G=96
¤ Dauer der Verarbeitung: 0.16 Sekunden
(vorverarbeitet am 2026-10-01)
¤
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