diff options
Diffstat (limited to 'drivers/i2c')
-rw-r--r-- | drivers/i2c/busses/Kconfig | 40 | ||||
-rw-r--r-- | drivers/i2c/busses/Makefile | 6 | ||||
-rw-r--r-- | drivers/i2c/i2c-core.c | 179 | ||||
-rw-r--r-- | drivers/i2c/i2c-smbus.c | 1 |
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; } |