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-rw-r--r--drivers/i2c/busses/Kconfig40
-rw-r--r--drivers/i2c/busses/Makefile6
-rw-r--r--drivers/i2c/i2c-core.c179
-rw-r--r--drivers/i2c/i2c-smbus.c1
4 files changed, 133 insertions, 93 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 87ab0568bb0e..bceafbfa7268 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -475,6 +475,26 @@ config I2C_PASEMI
help
Supports the PA Semi PWRficient on-chip SMBus interfaces.
+config I2C_PCA_PLATFORM
+ tristate "PCA9564/PCA9665 as platform device"
+ select I2C_ALGOPCA
+ default n
+ help
+ This driver supports a memory mapped Philips PCA9564/PCA9665
+ parallel bus to I2C bus controller.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-pca-platform.
+
+config I2C_PMCMSP
+ tristate "PMC MSP I2C TWI Controller"
+ depends on PMC_MSP
+ help
+ This driver supports the PMC TWI controller on MSP devices.
+
+ This driver can also be built as module. If so, the module
+ will be called i2c-pmcmsp.
+
config I2C_PNX
tristate "I2C bus support for Philips PNX targets"
depends on ARCH_PNX4008
@@ -711,26 +731,6 @@ config I2C_PCA_ISA
delays when I2C/SMBus chip drivers are loaded (e.g. at boot
time). If unsure, say N.
-config I2C_PCA_PLATFORM
- tristate "PCA9564/PCA9665 as platform device"
- select I2C_ALGOPCA
- default n
- help
- This driver supports a memory mapped Philips PCA9564/PCA9665
- parallel bus to I2C bus controller.
-
- This driver can also be built as a module. If so, the module
- will be called i2c-pca-platform.
-
-config I2C_PMCMSP
- tristate "PMC MSP I2C TWI Controller"
- depends on PMC_MSP
- help
- This driver supports the PMC TWI controller on MSP devices.
-
- This driver can also be built as module. If so, the module
- will be called i2c-pmcmsp.
-
config I2C_SIBYTE
tristate "SiByte SMBus interface"
depends on SIBYTE_SB1xxx_SOC
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 097236f631e8..936880bd1dc5 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -27,7 +27,7 @@ obj-$(CONFIG_I2C_VIAPRO) += i2c-viapro.o
obj-$(CONFIG_I2C_HYDRA) += i2c-hydra.o
obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o
-# Embebbed system I2C/SMBus host controller drivers
+# Embedded system I2C/SMBus host controller drivers
obj-$(CONFIG_I2C_AT91) += i2c-at91.o
obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o
obj-$(CONFIG_I2C_BLACKFIN_TWI) += i2c-bfin-twi.o
@@ -46,6 +46,8 @@ obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o
obj-$(CONFIG_I2C_OMAP) += i2c-omap.o
obj-$(CONFIG_I2C_PASEMI) += i2c-pasemi.o
+obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o
+obj-$(CONFIG_I2C_PMCMSP) += i2c-pmcmsp.o
obj-$(CONFIG_I2C_PNX) += i2c-pnx.o
obj-$(CONFIG_I2C_PXA) += i2c-pxa.o
obj-$(CONFIG_I2C_S3C2410) += i2c-s3c2410.o
@@ -68,8 +70,6 @@ obj-$(CONFIG_I2C_TINY_USB) += i2c-tiny-usb.o
obj-$(CONFIG_I2C_ACORN) += i2c-acorn.o
obj-$(CONFIG_I2C_ELEKTOR) += i2c-elektor.o
obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o
-obj-$(CONFIG_I2C_PCA_PLATFORM) += i2c-pca-platform.o
-obj-$(CONFIG_I2C_PMCMSP) += i2c-pmcmsp.o
obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o
obj-$(CONFIG_I2C_STUB) += i2c-stub.o
obj-$(CONFIG_SCx200_ACB) += scx200_acb.o
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index e0f833cca3f1..1cca2631e5b3 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -47,7 +47,6 @@ static DEFINE_MUTEX(core_lock);
static DEFINE_IDR(i2c_adapter_idr);
static struct device_type i2c_client_type;
-static int i2c_check_addr(struct i2c_adapter *adapter, int addr);
static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver);
/* ------------------------------------------------------------------------- */
@@ -371,6 +370,59 @@ struct i2c_client *i2c_verify_client(struct device *dev)
EXPORT_SYMBOL(i2c_verify_client);
+/* This is a permissive address validity check, I2C address map constraints
+ * are purposedly not enforced, except for the general call address. */
+static int i2c_check_client_addr_validity(const struct i2c_client *client)
+{
+ if (client->flags & I2C_CLIENT_TEN) {
+ /* 10-bit address, all values are valid */
+ if (client->addr > 0x3ff)
+ return -EINVAL;
+ } else {
+ /* 7-bit address, reject the general call address */
+ if (client->addr == 0x00 || client->addr > 0x7f)
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/* And this is a strict address validity check, used when probing. If a
+ * device uses a reserved address, then it shouldn't be probed. 7-bit
+ * addressing is assumed, 10-bit address devices are rare and should be
+ * explicitly enumerated. */
+static int i2c_check_addr_validity(unsigned short addr)
+{
+ /*
+ * Reserved addresses per I2C specification:
+ * 0x00 General call address / START byte
+ * 0x01 CBUS address
+ * 0x02 Reserved for different bus format
+ * 0x03 Reserved for future purposes
+ * 0x04-0x07 Hs-mode master code
+ * 0x78-0x7b 10-bit slave addressing
+ * 0x7c-0x7f Reserved for future purposes
+ */
+ if (addr < 0x08 || addr > 0x77)
+ return -EINVAL;
+ return 0;
+}
+
+static int __i2c_check_addr_busy(struct device *dev, void *addrp)
+{
+ struct i2c_client *client = i2c_verify_client(dev);
+ int addr = *(int *)addrp;
+
+ if (client && client->addr == addr)
+ return -EBUSY;
+ return 0;
+}
+
+static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
+{
+ return device_for_each_child(&adapter->dev, &addr,
+ __i2c_check_addr_busy);
+}
+
/**
* i2c_new_device - instantiate an i2c device
* @adap: the adapter managing the device
@@ -410,8 +462,16 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
strlcpy(client->name, info->type, sizeof(client->name));
+ /* Check for address validity */
+ status = i2c_check_client_addr_validity(client);
+ if (status) {
+ dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n",
+ client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr);
+ goto out_err_silent;
+ }
+
/* Check for address business */
- status = i2c_check_addr(adap, client->addr);
+ status = i2c_check_addr_busy(adap, client->addr);
if (status)
goto out_err;
@@ -436,6 +496,7 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
out_err:
dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x "
"(%d)\n", client->name, client->addr, status);
+out_err_silent:
kfree(client);
return NULL;
}
@@ -561,15 +622,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr,
return -EINVAL;
}
- if (info.addr < 0x03 || info.addr > 0x77) {
- dev_err(dev, "%s: Invalid I2C address 0x%hx\n", "new_device",
- info.addr);
- return -EINVAL;
- }
-
client = i2c_new_device(adap, &info);
if (!client)
- return -EEXIST;
+ return -EINVAL;
/* Keep track of the added device */
i2c_lock_adapter(adap);
@@ -1024,21 +1079,6 @@ EXPORT_SYMBOL(i2c_del_driver);
/* ------------------------------------------------------------------------- */
-static int __i2c_check_addr(struct device *dev, void *addrp)
-{
- struct i2c_client *client = i2c_verify_client(dev);
- int addr = *(int *)addrp;
-
- if (client && client->addr == addr)
- return -EBUSY;
- return 0;
-}
-
-static int i2c_check_addr(struct i2c_adapter *adapter, int addr)
-{
- return device_for_each_child(&adapter->dev, &addr, __i2c_check_addr);
-}
-
/**
* i2c_use_client - increments the reference count of the i2c client structure
* @client: the client being referenced
@@ -1277,6 +1317,41 @@ EXPORT_SYMBOL(i2c_master_recv);
* ----------------------------------------------------
*/
+/*
+ * Legacy default probe function, mostly relevant for SMBus. The default
+ * probe method is a quick write, but it is known to corrupt the 24RF08
+ * EEPROMs due to a state machine bug, and could also irreversibly
+ * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f,
+ * we use a short byte read instead. Also, some bus drivers don't implement
+ * quick write, so we fallback to a byte read in that case too.
+ * On x86, there is another special case for FSC hardware monitoring chips,
+ * which want regular byte reads (address 0x73.) Fortunately, these are the
+ * only known chips using this I2C address on PC hardware.
+ * Returns 1 if probe succeeded, 0 if not.
+ */
+static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
+{
+ int err;
+ union i2c_smbus_data dummy;
+
+#ifdef CONFIG_X86
+ if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON)
+ && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA))
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE_DATA, &dummy);
+ else
+#endif
+ if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50
+ || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE, &dummy);
+ else
+ err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0,
+ I2C_SMBUS_QUICK, NULL);
+
+ return err >= 0;
+}
+
static int i2c_detect_address(struct i2c_client *temp_client,
struct i2c_driver *driver)
{
@@ -1286,34 +1361,20 @@ static int i2c_detect_address(struct i2c_client *temp_client,
int err;
/* Make sure the address is valid */
- if (addr < 0x03 || addr > 0x77) {
+ err = i2c_check_addr_validity(addr);
+ if (err) {
dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n",
addr);
- return -EINVAL;
+ return err;
}
/* Skip if already in use */
- if (i2c_check_addr(adapter, addr))
+ if (i2c_check_addr_busy(adapter, addr))
return 0;
/* Make sure there is something at this address */
- if (addr == 0x73 && (adapter->class & I2C_CLASS_HWMON)) {
- /* Special probe for FSC hwmon chips */
- union i2c_smbus_data dummy;
-
- if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_READ, 0,
- I2C_SMBUS_BYTE_DATA, &dummy) < 0)
- return 0;
- } else {
- if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
- I2C_SMBUS_QUICK, NULL) < 0)
- return 0;
-
- /* Prevent 24RF08 corruption */
- if ((addr & ~0x0f) == 0x50)
- i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
- I2C_SMBUS_QUICK, NULL);
- }
+ if (!i2c_default_probe(adapter, addr))
+ return 0;
/* Finally call the custom detection function */
memset(&info, 0, sizeof(struct i2c_board_info));
@@ -1407,42 +1468,22 @@ i2c_new_probed_device(struct i2c_adapter *adap,
for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
/* Check address validity */
- if (addr_list[i] < 0x03 || addr_list[i] > 0x77) {
+ if (i2c_check_addr_validity(addr_list[i]) < 0) {
dev_warn(&adap->dev, "Invalid 7-bit address "
"0x%02x\n", addr_list[i]);
continue;
}
/* Check address availability */
- if (i2c_check_addr(adap, addr_list[i])) {
+ if (i2c_check_addr_busy(adap, addr_list[i])) {
dev_dbg(&adap->dev, "Address 0x%02x already in "
"use, not probing\n", addr_list[i]);
continue;
}
- /* Test address responsiveness
- The default probe method is a quick write, but it is known
- to corrupt the 24RF08 EEPROMs due to a state machine bug,
- and could also irreversibly write-protect some EEPROMs, so
- for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte
- read instead. Also, some bus drivers don't implement
- quick write, so we fallback to a byte read it that case
- too. */
- if ((addr_list[i] & ~0x07) == 0x30
- || (addr_list[i] & ~0x0f) == 0x50
- || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) {
- union i2c_smbus_data data;
-
- if (i2c_smbus_xfer(adap, addr_list[i], 0,
- I2C_SMBUS_READ, 0,
- I2C_SMBUS_BYTE, &data) >= 0)
- break;
- } else {
- if (i2c_smbus_xfer(adap, addr_list[i], 0,
- I2C_SMBUS_WRITE, 0,
- I2C_SMBUS_QUICK, NULL) >= 0)
- break;
- }
+ /* Test address responsiveness */
+ if (i2c_default_probe(adap, addr_list[i]))
+ break;
}
if (addr_list[i] == I2C_CLIENT_END) {
diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index a24e0bfe9201..f61ccc1e5ea3 100644
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -173,7 +173,6 @@ static int smbalert_remove(struct i2c_client *ara)
cancel_work_sync(&alert->alert);
- i2c_set_clientdata(ara, NULL);
kfree(alert);
return 0;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-22 16:26:10 +0000