microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность

Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging 

* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c-viapro: Don't log nacks
  i2c/pca954x: Remove __devinit and __devexit from probe and remove functions
  MAINTAINERS: Add maintainer for PCA9541 I2C bus master selector driver
  i2c/mux: Driver for PCA9541 I2C Master Selector
  i2c: Optimize function i2c_detect()
  i2c: Discard warning message on device instantiation from user-space
  i2c-amd8111: Add proper error handling
  i2c: Change to new flag variable
  i2c: Remove unneeded inclusions of <linux/i2c-id.h>
  i2c: Let i2c_parent_is_i2c_adapter return the parent adapter
  i2c: Simplify i2c_parent_is_i2c_adapter
  i2c-pca-platform: Change device name of request_irq
  i2c: Fix Kconfig dependencies
This commit is contained in:
Linus Torvalds 2010-10-24 12:46:24 -07:00
Родитель 7c024e9534 bf5d95c826
Коммит bdaf12b412
26 изменённых файлов: 603 добавлений и 117 удалений
Показать статистику Скачать Patch файл Скачать Diff файл Показать все файлы Свернуть все файлы

6
MAINTAINERS
Просмотреть файл

@ -4541,6 +4541,12 @@ S: Maintained
F: drivers/leds/leds-pca9532.c
F: include/linux/leds-pca9532.h
PCA9541 I2C BUS MASTER SELECTOR DRIVER
M: Guenter Roeck <guenter.roeck@ericsson.com>
L: linux-i2c@vger.kernel.org
S: Maintained
F: drivers/i2c/muxes/pca9541.c
PCA9564/PCA9665 I2C BUS DRIVER
M: Wolfram Sang <w.sang@pengutronix.de>
L: linux-i2c@vger.kernel.org

1
drivers/gpu/drm/nouveau/nouveau_i2c.h
Просмотреть файл

@ -24,7 +24,6 @@
#define __NOUVEAU_I2C_H__
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include "drm_dp_helper.h"

1
drivers/gpu/drm/radeon/radeon_mode.h
Просмотреть файл

@ -36,7 +36,6 @@
#include <drm_dp_helper.h>
#include <drm_fixed.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
struct radeon_bo;

3
drivers/i2c/Kconfig
Просмотреть файл

@ -75,7 +75,8 @@ config I2C_HELPER_AUTO
In doubt, say Y.
config I2C_SMBUS
tristate "SMBus-specific protocols" if !I2C_HELPER_AUTO
tristate
prompt "SMBus-specific protocols" if !I2C_HELPER_AUTO
help
Say Y here if you want support for SMBus extensions to the I2C
specification. At the moment, the only supported extension is

4
drivers/i2c/Makefile
Просмотреть файл

@ -9,6 +9,4 @@ obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o
obj-$(CONFIG_I2C_MUX) += i2c-mux.o
obj-y += algos/ busses/ muxes/
ifeq ($(CONFIG_I2C_DEBUG_CORE),y)
EXTRA_CFLAGS += -DDEBUG
endif
ccflags-$(CONFIG_I2C_DEBUG_CORE) := -DDEBUG

12
drivers/i2c/algos/Kconfig
Просмотреть файл

@ -15,3 +15,15 @@ config I2C_ALGOPCA
tristate "I2C PCA 9564 interfaces"
endmenu
# In automatic configuration mode, we still have to define the
# symbols to avoid unmet dependencies.
if I2C_HELPER_AUTO
config I2C_ALGOBIT
tristate
config I2C_ALGOPCF
tristate
config I2C_ALGOPCA
tristate
endif

4
drivers/i2c/algos/Makefile
Просмотреть файл

@ -6,6 +6,4 @@ obj-$(CONFIG_I2C_ALGOBIT) += i2c-algo-bit.o
obj-$(CONFIG_I2C_ALGOPCF) += i2c-algo-pcf.o
obj-$(CONFIG_I2C_ALGOPCA) += i2c-algo-pca.o
ifeq ($(CONFIG_I2C_DEBUG_ALGO),y)
EXTRA_CFLAGS += -DDEBUG
endif
ccflags-$(CONFIG_I2C_DEBUG_ALGO) := -DDEBUG

4
drivers/i2c/busses/Makefile
Просмотреть файл

@ -76,6 +76,4 @@ obj-$(CONFIG_I2C_STUB) += i2c-stub.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
obj-$(CONFIG_SCx200_I2C) += scx200_i2c.o
ifeq ($(CONFIG_I2C_DEBUG_BUS),y)
EXTRA_CFLAGS += -DDEBUG
endif
ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG

163
drivers/i2c/busses/i2c-amd8111.c
Просмотреть файл

@ -69,7 +69,7 @@ static struct pci_driver amd8111_driver;
* ACPI 2.0 chapter 13 access of registers of the EC
*/
static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
static int amd_ec_wait_write(struct amd_smbus *smbus)
{
int timeout = 500;
@ -85,7 +85,7 @@ static unsigned int amd_ec_wait_write(struct amd_smbus *smbus)
return 0;
}
static unsigned int amd_ec_wait_read(struct amd_smbus *smbus)
static int amd_ec_wait_read(struct amd_smbus *smbus)
{
int timeout = 500;
@ -101,7 +101,7 @@ static unsigned int amd_ec_wait_read(struct amd_smbus *smbus)
return 0;
}
static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
static int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
unsigned char *data)
{
int status;
@ -124,7 +124,7 @@ static unsigned int amd_ec_read(struct amd_smbus *smbus, unsigned char address,
return 0;
}
static unsigned int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
static int amd_ec_write(struct amd_smbus *smbus, unsigned char address,
unsigned char data)
{
int status;
@ -196,7 +196,7 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
{
struct amd_smbus *smbus = adap->algo_data;
unsigned char protocol, len, pec, temp[2];
int i;
int i, status;
protocol = (read_write == I2C_SMBUS_READ) ? AMD_SMB_PRTCL_READ
: AMD_SMB_PRTCL_WRITE;
@ -209,38 +209,62 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
break;
case I2C_SMBUS_BYTE:
if (read_write == I2C_SMBUS_WRITE)
amd_ec_write(smbus, AMD_SMB_CMD, command);
if (read_write == I2C_SMBUS_WRITE) {
status = amd_ec_write(smbus, AMD_SMB_CMD,
command);
if (status)
return status;
}
protocol |= AMD_SMB_PRTCL_BYTE;
break;
case I2C_SMBUS_BYTE_DATA:
amd_ec_write(smbus, AMD_SMB_CMD, command);
if (read_write == I2C_SMBUS_WRITE)
amd_ec_write(smbus, AMD_SMB_DATA, data->byte);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
if (read_write == I2C_SMBUS_WRITE) {
status = amd_ec_write(smbus, AMD_SMB_DATA,
data->byte);
if (status)
return status;
}
protocol |= AMD_SMB_PRTCL_BYTE_DATA;
break;
case I2C_SMBUS_WORD_DATA:
amd_ec_write(smbus, AMD_SMB_CMD, command);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
if (read_write == I2C_SMBUS_WRITE) {
amd_ec_write(smbus, AMD_SMB_DATA,
data->word & 0xff);
amd_ec_write(smbus, AMD_SMB_DATA + 1,
data->word >> 8);
status = amd_ec_write(smbus, AMD_SMB_DATA,
data->word & 0xff);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
data->word >> 8);
if (status)
return status;
}
protocol |= AMD_SMB_PRTCL_WORD_DATA | pec;
break;
case I2C_SMBUS_BLOCK_DATA:
amd_ec_write(smbus, AMD_SMB_CMD, command);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
if (read_write == I2C_SMBUS_WRITE) {
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX);
amd_ec_write(smbus, AMD_SMB_BCNT, len);
for (i = 0; i < len; i++)
amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
if (status)
return status;
for (i = 0; i < len; i++) {
status =
amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
if (status)
return status;
}
}
protocol |= AMD_SMB_PRTCL_BLOCK_DATA | pec;
break;
@ -248,19 +272,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
case I2C_SMBUS_I2C_BLOCK_DATA:
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX);
amd_ec_write(smbus, AMD_SMB_CMD, command);
amd_ec_write(smbus, AMD_SMB_BCNT, len);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
if (status)
return status;
if (read_write == I2C_SMBUS_WRITE)
for (i = 0; i < len; i++)
amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
for (i = 0; i < len; i++) {
status =
amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
if (status)
return status;
}
protocol |= AMD_SMB_PRTCL_I2C_BLOCK_DATA;
break;
case I2C_SMBUS_PROC_CALL:
amd_ec_write(smbus, AMD_SMB_CMD, command);
amd_ec_write(smbus, AMD_SMB_DATA, data->word & 0xff);
amd_ec_write(smbus, AMD_SMB_DATA + 1, data->word >> 8);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_DATA,
data->word & 0xff);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_DATA + 1,
data->word >> 8);
if (status)
return status;
protocol = AMD_SMB_PRTCL_PROC_CALL | pec;
read_write = I2C_SMBUS_READ;
break;
@ -268,11 +308,18 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
case I2C_SMBUS_BLOCK_PROC_CALL:
len = min_t(u8, data->block[0],
I2C_SMBUS_BLOCK_MAX - 1);
amd_ec_write(smbus, AMD_SMB_CMD, command);
amd_ec_write(smbus, AMD_SMB_BCNT, len);
for (i = 0; i < len; i++)
amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
status = amd_ec_write(smbus, AMD_SMB_CMD, command);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_BCNT, len);
if (status)
return status;
for (i = 0; i < len; i++) {
status = amd_ec_write(smbus, AMD_SMB_DATA + i,
data->block[i + 1]);
if (status)
return status;
}
protocol = AMD_SMB_PRTCL_BLOCK_PROC_CALL | pec;
read_write = I2C_SMBUS_READ;
break;
@ -282,24 +329,29 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
return -EOPNOTSUPP;
}
amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
status = amd_ec_write(smbus, AMD_SMB_ADDR, addr << 1);
if (status)
return status;
status = amd_ec_write(smbus, AMD_SMB_PRTCL, protocol);
if (status)
return status;
/* FIXME this discards status from ec_read(); so temp[0] will
* hold stack garbage ... the rest of this routine will act
* nonsensically. Ignored ec_write() status might explain
* some such failures...
*/
amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
if (status)
return status;
if (~temp[0] & AMD_SMB_STS_DONE) {
udelay(500);
amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
if (status)
return status;
}
if (~temp[0] & AMD_SMB_STS_DONE) {
msleep(1);
amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
status = amd_ec_read(smbus, AMD_SMB_STS, temp + 0);
if (status)
return status;
}
if ((~temp[0] & AMD_SMB_STS_DONE) || (temp[0] & AMD_SMB_STS_STATUS))
@ -311,24 +363,35 @@ static s32 amd8111_access(struct i2c_adapter * adap, u16 addr,
switch (size) {
case I2C_SMBUS_BYTE:
case I2C_SMBUS_BYTE_DATA:
amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
status = amd_ec_read(smbus, AMD_SMB_DATA, &data->byte);
if (status)
return status;
break;
case I2C_SMBUS_WORD_DATA:
case I2C_SMBUS_PROC_CALL:
amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
status = amd_ec_read(smbus, AMD_SMB_DATA, temp + 0);
if (status)
return status;
status = amd_ec_read(smbus, AMD_SMB_DATA + 1, temp + 1);
if (status)
return status;
data->word = (temp[1] << 8) | temp[0];
break;
case I2C_SMBUS_BLOCK_DATA:
case I2C_SMBUS_BLOCK_PROC_CALL:
amd_ec_read(smbus, AMD_SMB_BCNT, &len);
status = amd_ec_read(smbus, AMD_SMB_BCNT, &len);
if (status)
return status;
len = min_t(u8, len, I2C_SMBUS_BLOCK_MAX);
case I2C_SMBUS_I2C_BLOCK_DATA:
for (i = 0; i < len; i++)
amd_ec_read(smbus, AMD_SMB_DATA + i,
data->block + i + 1);
for (i = 0; i < len; i++) {
status = amd_ec_read(smbus, AMD_SMB_DATA + i,
data->block + i + 1);
if (status)
return status;
}
data->block[0] = len;
break;
}

1
drivers/i2c/busses/i2c-ibm_iic.c
Просмотреть файл

@ -41,7 +41,6 @@
#include <asm/irq.h>
#include <linux/io.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/of_platform.h>
#include <linux/of_i2c.h>

1
drivers/i2c/busses/i2c-nuc900.c
Просмотреть файл

@ -16,7 +16,6 @@
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>

2
drivers/i2c/busses/i2c-pca-platform.c
Просмотреть файл

@ -224,7 +224,7 @@ static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
if (irq) {
ret = request_irq(irq, i2c_pca_pf_handler,
IRQF_TRIGGER_FALLING, i2c->adap.name, i2c);
IRQF_TRIGGER_FALLING, pdev->name, i2c);
if (ret)
goto e_reqirq;
}

1
drivers/i2c/busses/i2c-pxa.c
Просмотреть файл

@ -22,7 +22,6 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/sched.h>

1
drivers/i2c/busses/i2c-s3c2410.c
Просмотреть файл

@ -24,7 +24,6 @@
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>

8
drivers/i2c/busses/i2c-viapro.c
Просмотреть файл

@ -185,14 +185,8 @@ static int vt596_transaction(u8 size)
}
if (temp & 0x04) {
int read = inb_p(SMBHSTADD) & 0x01;
result = -ENXIO;
/* The quick and receive byte commands are used to probe
for chips, so errors are expected, and we don't want
to frighten the user. */
if (!((size == VT596_QUICK && !read) ||
(size == VT596_BYTE && read)))
dev_err(&vt596_adapter.dev, "Transaction error!\n");
dev_dbg(&vt596_adapter.dev, "No response\n");
}
/* Resetting status register */

45
drivers/i2c/i2c-core.c
Просмотреть файл

@ -425,14 +425,14 @@ static int __i2c_check_addr_busy(struct device *dev, void *addrp)
/* walk up mux tree */
static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
int result;
result = device_for_each_child(&adapter->dev, &addr,
__i2c_check_addr_busy);
if (!result && i2c_parent_is_i2c_adapter(adapter))
result = i2c_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (!result && parent)
result = i2c_check_mux_parents(parent, addr);
return result;
}
@ -453,11 +453,11 @@ static int i2c_check_mux_children(struct device *dev, void *addrp)
static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
int result = 0;
if (i2c_parent_is_i2c_adapter(adapter))
result = i2c_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (parent)
result = i2c_check_mux_parents(parent, addr);
if (!result)
result = device_for_each_child(&adapter->dev, &addr,
@ -472,8 +472,10 @@ static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
*/
void i2c_lock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
i2c_lock_adapter(to_i2c_adapter(adapter->dev.parent));
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
if (parent)
i2c_lock_adapter(parent);
else
rt_mutex_lock(&adapter->bus_lock);
}
@ -485,8 +487,10 @@ EXPORT_SYMBOL_GPL(i2c_lock_adapter);
*/
static int i2c_trylock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
return i2c_trylock_adapter(to_i2c_adapter(adapter->dev.parent));
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
if (parent)
return i2c_trylock_adapter(parent);
else
return rt_mutex_trylock(&adapter->bus_lock);
}
@ -497,8 +501,10 @@ static int i2c_trylock_adapter(struct i2c_adapter *adapter)
*/
void i2c_unlock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
i2c_unlock_adapter(to_i2c_adapter(adapter->dev.parent));
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
if (parent)
i2c_unlock_adapter(parent);
else
rt_mutex_unlock(&adapter->bus_lock);
}
@ -677,8 +683,6 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr,
char *blank, end;
int res;
dev_warn(dev, "The new_device interface is still experimental "
"and may change in a near future\n");
memset(&info, 0, sizeof(struct i2c_board_info));
blank = strchr(buf, ' ');
@ -1504,26 +1508,25 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
if (!driver->detect || !address_list)
return 0;
/* Stop here if the classes do not match */
if (!(adapter->class & driver->class))
return 0;
/* Set up a temporary client to help detect callback */
temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL);
if (!temp_client)
return -ENOMEM;
temp_client->adapter = adapter;
/* Stop here if the classes do not match */
if (!(adapter->class & driver->class))
goto exit_free;
for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
"addr 0x%02x\n", adap_id, address_list[i]);
temp_client->addr = address_list[i];
err = i2c_detect_address(temp_client, driver);
if (err)
goto exit_free;
if (unlikely(err))
break;
}
exit_free:
kfree(temp_client);
return err;
}

13
drivers/i2c/i2c-dev.c
Просмотреть файл

@ -192,13 +192,12 @@ static int i2cdev_check(struct device *dev, void *addrp)
/* walk up mux tree */
static int i2cdev_check_mux_parents(struct i2c_adapter *adapter, int addr)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
int result;
result = device_for_each_child(&adapter->dev, &addr, i2cdev_check);
if (!result && i2c_parent_is_i2c_adapter(adapter))
result = i2cdev_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (!result && parent)
result = i2cdev_check_mux_parents(parent, addr);
return result;
}
@ -222,11 +221,11 @@ static int i2cdev_check_mux_children(struct device *dev, void *addrp)
driver bound to it, as NOT busy. */
static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
int result = 0;
if (i2c_parent_is_i2c_adapter(adapter))
result = i2cdev_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (parent)
result = i2cdev_check_mux_parents(parent, addr);
if (!result)
result = device_for_each_child(&adapter->dev, &addr,

10
drivers/i2c/muxes/Kconfig
Просмотреть файл

@ -5,6 +5,16 @@
menu "Multiplexer I2C Chip support"
depends on I2C_MUX
config I2C_MUX_PCA9541
tristate "NXP PCA9541 I2C Master Selector"
depends on EXPERIMENTAL
help
If you say yes here you get support for the NXP PCA9541
I2C Master Selector.
This driver can also be built as a module. If so, the module
will be called pca9541.
config I2C_MUX_PCA954x
tristate "Philips PCA954x I2C Mux/switches"
depends on EXPERIMENTAL

5
drivers/i2c/muxes/Makefile
Просмотреть файл

@ -1,8 +1,7 @@
#
# Makefile for multiplexer I2C chip drivers.
obj-$(CONFIG_I2C_MUX_PCA9541) += pca9541.o
obj-$(CONFIG_I2C_MUX_PCA954x) += pca954x.o
ifeq ($(CONFIG_I2C_DEBUG_BUS),y)
EXTRA_CFLAGS += -DDEBUG
endif
ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG

411
drivers/i2c/muxes/pca9541.c Normal file
Просмотреть файл

@ -0,0 +1,411 @@
/*
* I2C multiplexer driver for PCA9541 bus master selector
*
* Copyright (c) 2010 Ericsson AB.
*
* Author: Guenter Roeck <guenter.roeck@ericsson.com>
*
* Derived from:
* pca954x.c
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/i2c/pca954x.h>
/*
* The PCA9541 is a bus master selector. It supports two I2C masters connected
* to a single slave bus.
*
* Before each bus transaction, a master has to acquire bus ownership. After the
* transaction is complete, bus ownership has to be released. This fits well
* into the I2C multiplexer framework, which provides select and release
* functions for this purpose. For this reason, this driver is modeled as
* single-channel I2C bus multiplexer.
*
* This driver assumes that the two bus masters are controlled by two different
* hosts. If a single host controls both masters, platform code has to ensure
* that only one of the masters is instantiated at any given time.
*/
#define PCA9541_CONTROL 0x01
#define PCA9541_ISTAT 0x02
#define PCA9541_CTL_MYBUS (1 << 0)
#define PCA9541_CTL_NMYBUS (1 << 1)
#define PCA9541_CTL_BUSON (1 << 2)
#define PCA9541_CTL_NBUSON (1 << 3)
#define PCA9541_CTL_BUSINIT (1 << 4)
#define PCA9541_CTL_TESTON (1 << 6)
#define PCA9541_CTL_NTESTON (1 << 7)
#define PCA9541_ISTAT_INTIN (1 << 0)
#define PCA9541_ISTAT_BUSINIT (1 << 1)
#define PCA9541_ISTAT_BUSOK (1 << 2)
#define PCA9541_ISTAT_BUSLOST (1 << 3)
#define PCA9541_ISTAT_MYTEST (1 << 6)
#define PCA9541_ISTAT_NMYTEST (1 << 7)
#define BUSON (PCA9541_CTL_BUSON | PCA9541_CTL_NBUSON)
#define MYBUS (PCA9541_CTL_MYBUS | PCA9541_CTL_NMYBUS)
#define mybus(x) (!((x) & MYBUS) || ((x) & MYBUS) == MYBUS)
#define busoff(x) (!((x) & BUSON) || ((x) & BUSON) == BUSON)
/* arbitration timeouts, in jiffies */
#define ARB_TIMEOUT (HZ / 8) /* 125 ms until forcing bus ownership */
#define ARB2_TIMEOUT (HZ / 4) /* 250 ms until acquisition failure */
/* arbitration retry delays, in us */
#define SELECT_DELAY_SHORT 50
#define SELECT_DELAY_LONG 1000
struct pca9541 {
struct i2c_adapter *mux_adap;
unsigned long select_timeout;
unsigned long arb_timeout;
};
static const struct i2c_device_id pca9541_id[] = {
{"pca9541", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, pca9541_id);
/*
* Write to chip register. Don't use i2c_transfer()/i2c_smbus_xfer()
* as they will try to lock the adapter a second time.
*/
static int pca9541_reg_write(struct i2c_client *client, u8 command, u8 val)
{
struct i2c_adapter *adap = client->adapter;
int ret;
if (adap->algo->master_xfer) {
struct i2c_msg msg;
char buf[2];
msg.addr = client->addr;
msg.flags = 0;
msg.len = 2;
buf[0] = command;
buf[1] = val;
msg.buf = buf;
ret = adap->algo->master_xfer(adap, &msg, 1);
} else {
union i2c_smbus_data data;
data.byte = val;
ret = adap->algo->smbus_xfer(adap, client->addr,
client->flags,
I2C_SMBUS_WRITE,
command,
I2C_SMBUS_BYTE_DATA, &data);
}
return ret;
}
/*
* Read from chip register. Don't use i2c_transfer()/i2c_smbus_xfer()
* as they will try to lock adapter a second time.
*/
static int pca9541_reg_read(struct i2c_client *client, u8 command)
{
struct i2c_adapter *adap = client->adapter;
int ret;
u8 val;
if (adap->algo->master_xfer) {
struct i2c_msg msg[2] = {
{
.addr = client->addr,
.flags = 0,
.len = 1,
.buf = &command
},
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = 1,
.buf = &val
}
};
ret = adap->algo->master_xfer(adap, msg, 2);
if (ret == 2)
ret = val;
else if (ret >= 0)
ret = -EIO;
} else {
union i2c_smbus_data data;
ret = adap->algo->smbus_xfer(adap, client->addr,
client->flags,
I2C_SMBUS_READ,
command,
I2C_SMBUS_BYTE_DATA, &data);
if (!ret)
ret = data.byte;
}
return ret;
}
/*
* Arbitration management functions
*/
/* Release bus. Also reset NTESTON and BUSINIT if it was set. */
static void pca9541_release_bus(struct i2c_client *client)
{
int reg;
reg = pca9541_reg_read(client, PCA9541_CONTROL);
if (reg >= 0 && !busoff(reg) && mybus(reg))
pca9541_reg_write(client, PCA9541_CONTROL,
(reg & PCA9541_CTL_NBUSON) >> 1);
}
/*
* Arbitration is defined as a two-step process. A bus master can only activate
* the slave bus if it owns it; otherwise it has to request ownership first.
* This multi-step process ensures that access contention is resolved
* gracefully.
*
* Bus Ownership Other master Action
* state requested access
* ----------------------------------------------------
* off - yes wait for arbitration timeout or
* for other master to drop request
* off no no take ownership
* off yes no turn on bus
* on yes - done
* on no - wait for arbitration timeout or
* for other master to release bus
*
* The main contention point occurs if the slave bus is off and both masters
* request ownership at the same time. In this case, one master will turn on
* the slave bus, believing that it owns it. The other master will request
* bus ownership. Result is that the bus is turned on, and master which did
* _not_ own the slave bus before ends up owning it.
*/
/* Control commands per PCA9541 datasheet */
static const u8 pca9541_control[16] = {
4, 0, 1, 5, 4, 4, 5, 5, 0, 0, 1, 1, 0, 4, 5, 1
};
/*
* Channel arbitration
*
* Return values:
* <0: error
* 0 : bus not acquired
* 1 : bus acquired
*/
static int pca9541_arbitrate(struct i2c_client *client)
{
struct pca9541 *data = i2c_get_clientdata(client);
int reg;
reg = pca9541_reg_read(client, PCA9541_CONTROL);
if (reg < 0)
return reg;
if (busoff(reg)) {
int istat;
/*
* Bus is off. Request ownership or turn it on unless
* other master requested ownership.
*/
istat = pca9541_reg_read(client, PCA9541_ISTAT);
if (!(istat & PCA9541_ISTAT_NMYTEST)
|| time_is_before_eq_jiffies(data->arb_timeout)) {
/*
* Other master did not request ownership,
* or arbitration timeout expired. Take the bus.
*/
pca9541_reg_write(client,
PCA9541_CONTROL,
pca9541_control[reg & 0x0f]
| PCA9541_CTL_NTESTON);
data->select_timeout = SELECT_DELAY_SHORT;
} else {
/*
* Other master requested ownership.
* Set extra long timeout to give it time to acquire it.
*/
data->select_timeout = SELECT_DELAY_LONG * 2;
}
} else if (mybus(reg)) {
/*
* Bus is on, and we own it. We are done with acquisition.
* Reset NTESTON and BUSINIT, then return success.
*/
if (reg & (PCA9541_CTL_NTESTON | PCA9541_CTL_BUSINIT))
pca9541_reg_write(client,
PCA9541_CONTROL,
reg & ~(PCA9541_CTL_NTESTON
| PCA9541_CTL_BUSINIT));
return 1;
} else {
/*
* Other master owns the bus.
* If arbitration timeout has expired, force ownership.
* Otherwise request it.
*/
data->select_timeout = SELECT_DELAY_LONG;
if (time_is_before_eq_jiffies(data->arb_timeout)) {
/* Time is up, take the bus and reset it. */
pca9541_reg_write(client,
PCA9541_CONTROL,
pca9541_control[reg & 0x0f]
| PCA9541_CTL_BUSINIT
| PCA9541_CTL_NTESTON);
} else {
/* Request bus ownership if needed */
if (!(reg & PCA9541_CTL_NTESTON))
pca9541_reg_write(client,
PCA9541_CONTROL,
reg | PCA9541_CTL_NTESTON);
}
}
return 0;
}
static int pca9541_select_chan(struct i2c_adapter *adap, void *client, u32 chan)
{
struct pca9541 *data = i2c_get_clientdata(client);
int ret;
unsigned long timeout = jiffies + ARB2_TIMEOUT;
/* give up after this time */
data->arb_timeout = jiffies + ARB_TIMEOUT;
/* force bus ownership after this time */
do {
ret = pca9541_arbitrate(client);
if (ret)
return ret < 0 ? ret : 0;
if (data->select_timeout == SELECT_DELAY_SHORT)
udelay(data->select_timeout);
else
msleep(data->select_timeout / 1000);
} while (time_is_after_eq_jiffies(timeout));
return -ETIMEDOUT;
}
static int pca9541_release_chan(struct i2c_adapter *adap,
void *client, u32 chan)
{
pca9541_release_bus(client);
return 0;
}
/*
* I2C init/probing/exit functions
*/
static int pca9541_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adap = client->adapter;
struct pca954x_platform_data *pdata = client->dev.platform_data;
struct pca9541 *data;
int force;
int ret = -ENODEV;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE_DATA))
goto err;
data = kzalloc(sizeof(struct pca9541), GFP_KERNEL);
if (!data) {
ret = -ENOMEM;
goto err;
}
i2c_set_clientdata(client, data);
/*
* I2C accesses are unprotected here.
* We have to lock the adapter before releasing the bus.
*/
i2c_lock_adapter(adap);
pca9541_release_bus(client);
i2c_unlock_adapter(adap);
/* Create mux adapter */
force = 0;
if (pdata)
force = pdata->modes[0].adap_id;
data->mux_adap = i2c_add_mux_adapter(adap, client, force, 0,
pca9541_select_chan,
pca9541_release_chan);
if (data->mux_adap == NULL) {
dev_err(&client->dev, "failed to register master selector\n");
goto exit_free;
}
dev_info(&client->dev, "registered master selector for I2C %s\n",
client->name);
return 0;
exit_free:
kfree(data);
err:
return ret;
}
static int pca9541_remove(struct i2c_client *client)
{
struct pca9541 *data = i2c_get_clientdata(client);
i2c_del_mux_adapter(data->mux_adap);
kfree(data);
return 0;
}
static struct i2c_driver pca9541_driver = {
.driver = {
.name = "pca9541",
.owner = THIS_MODULE,
},
.probe = pca9541_probe,
.remove = pca9541_remove,
.id_table = pca9541_id,
};
static int __init pca9541_init(void)
{
return i2c_add_driver(&pca9541_driver);
}
static void __exit pca9541_exit(void)
{
i2c_del_driver(&pca9541_driver);
}
module_init(pca9541_init);
module_exit(pca9541_exit);
MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>");
MODULE_DESCRIPTION("PCA9541 I2C master selector driver");
MODULE_LICENSE("GPL v2");

8
drivers/i2c/muxes/pca954x.c
Просмотреть файл

@ -181,8 +181,8 @@ static int pca954x_deselect_mux(struct i2c_adapter *adap,
/*
* I2C init/probing/exit functions
*/
static int __devinit pca954x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
static int pca954x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
struct pca954x_platform_data *pdata = client->dev.platform_data;
@ -255,7 +255,7 @@ err:
return ret;
}
static int __devexit pca954x_remove(struct i2c_client *client)
static int pca954x_remove(struct i2c_client *client)
{
struct pca954x *data = i2c_get_clientdata(client);
const struct chip_desc *chip = &chips[data->type];
@ -279,7 +279,7 @@ static struct i2c_driver pca954x_driver = {
.owner = THIS_MODULE,
},
.probe = pca954x_probe,
.remove = __devexit_p(pca954x_remove),
.remove = pca954x_remove,
.id_table = pca954x_id,
};

1
drivers/video/aty/radeon_i2c.c
Просмотреть файл

@ -7,7 +7,6 @@
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include <asm/io.h>

1
drivers/video/i810/i810.h
Просмотреть файл

@ -17,7 +17,6 @@
#include <linux/agp_backend.h>
#include <linux/fb.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include <video/vga.h>

1
drivers/video/intelfb/intelfb_i2c.c
Просмотреть файл

@ -32,7 +32,6 @@ USE OR OTHER DEALINGS IN THE SOFTWARE.
#include <linux/fb.h>
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include <asm/io.h>

1
drivers/video/savage/savagefb.h
Просмотреть файл

@ -13,7 +13,6 @@
#define __SAVAGEFB_H__
#include <linux/i2c.h>
#include <linux/i2c-id.h>
#include <linux/i2c-algo-bit.h>
#include <linux/mutex.h>
#include <video/vga.h>

12
include/linux/i2c.h
Просмотреть файл

@ -384,11 +384,15 @@ static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
dev_set_drvdata(&dev->dev, data);
}
static inline int i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
static inline struct i2c_adapter *
i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
{
return adapter->dev.parent != NULL
&& adapter->dev.parent->bus == &i2c_bus_type
&& adapter->dev.parent->type == &i2c_adapter_type;
struct device *parent = adapter->dev.parent;
if (parent != NULL && parent->type == &i2c_adapter_type)
return to_i2c_adapter(parent);
else
return NULL;
}
/* Adapter locking functions, exported for shared pin cases */