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author | Len Brown <len.brown@intel.com> | 2005-12-06 17:31:30 -0500 |
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committer | Len Brown <len.brown@intel.com> | 2005-12-06 17:31:30 -0500 |
commit | 3d5271f9883cba7b54762bc4fe027d4172f06db7 (patch) | |
tree | ab8a881a14478598a0c8bda0d26c62cdccfffd6d /drivers/i2c/i2c-core.c | |
parent | 378b2556f4e09fa6f87ff0cb5c4395ff28257d02 (diff) | |
parent | 9115a6c787596e687df03010d97fccc5e0762506 (diff) | |
download | linux-stable-3d5271f9883cba7b54762bc4fe027d4172f06db7.tar.gz linux-stable-3d5271f9883cba7b54762bc4fe027d4172f06db7.tar.bz2 linux-stable-3d5271f9883cba7b54762bc4fe027d4172f06db7.zip |
Pull release into acpica branch
Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r-- | drivers/i2c/i2c-core.c | 199 |
1 files changed, 72 insertions, 127 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c index dda472e5e8be..82ea1b7ec914 100644 --- a/drivers/i2c/i2c-core.c +++ b/drivers/i2c/i2c-core.c @@ -19,7 +19,8 @@ /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> - SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> */ + SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and + Jean Delvare <khali@linux-fr.org> */ #include <linux/module.h> #include <linux/kernel.h> @@ -29,6 +30,7 @@ #include <linux/init.h> #include <linux/idr.h> #include <linux/seq_file.h> +#include <linux/platform_device.h> #include <asm/uaccess.h> @@ -48,7 +50,7 @@ static int i2c_bus_suspend(struct device * dev, pm_message_t state) int rc = 0; if (dev->driver && dev->driver->suspend) - rc = dev->driver->suspend(dev,state,0); + rc = dev->driver->suspend(dev, state); return rc; } @@ -57,7 +59,7 @@ static int i2c_bus_resume(struct device * dev) int rc = 0; if (dev->driver && dev->driver->resume) - rc = dev->driver->resume(dev,0); + rc = dev->driver->resume(dev); return rc; } @@ -85,6 +87,7 @@ void i2c_adapter_dev_release(struct device *dev) } struct device_driver i2c_adapter_driver = { + .owner = THIS_MODULE, .name = "i2c_adapter", .bus = &i2c_bus_type, .probe = i2c_device_probe, @@ -98,6 +101,7 @@ static void i2c_adapter_class_dev_release(struct class_device *dev) } struct class i2c_adapter_class = { + .owner = THIS_MODULE, .name = "i2c-adapter", .release = &i2c_adapter_class_dev_release, }; @@ -291,6 +295,7 @@ int i2c_add_driver(struct i2c_driver *driver) down(&core_lists); /* add the driver to the list of i2c drivers in the driver core */ + driver->driver.owner = driver->owner; driver->driver.name = driver->name; driver->driver.bus = &i2c_bus_type; driver->driver.probe = i2c_device_probe; @@ -706,10 +711,6 @@ int i2c_probe(struct i2c_adapter *adapter, int i, err; int adap_id = i2c_adapter_id(adapter); - /* Forget it if we can't probe using SMBUS_QUICK */ - if (! i2c_check_functionality(adapter,I2C_FUNC_SMBUS_QUICK)) - return -1; - /* Force entries are done first, and are not affected by ignore entries */ if (address_data->forces) { @@ -736,6 +737,17 @@ int i2c_probe(struct i2c_adapter *adapter, } } + /* Stop here if we can't use SMBUS_QUICK */ + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) { + if (address_data->probe[0] == I2C_CLIENT_END + && address_data->normal_i2c[0] == I2C_CLIENT_END) + return 0; + + dev_warn(&adapter->dev, "SMBus Quick command not supported, " + "can't probe for chips\n"); + return -1; + } + /* Probe entries are done second, and are not affected by ignore entries either */ for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) { @@ -820,101 +832,44 @@ crc8(u16 data) return (u8)(data >> 8); } -/* CRC over count bytes in the first array plus the bytes in the rest - array if it is non-null. rest[0] is the (length of rest) - 1 - and is included. */ -static u8 i2c_smbus_partial_pec(u8 crc, int count, u8 *first, u8 *rest) +/* Incremental CRC8 over count bytes in the array pointed to by p */ +static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) { int i; for(i = 0; i < count; i++) - crc = crc8((crc ^ first[i]) << 8); - if(rest != NULL) - for(i = 0; i <= rest[0]; i++) - crc = crc8((crc ^ rest[i]) << 8); + crc = crc8((crc ^ p[i]) << 8); return crc; } -static u8 i2c_smbus_pec(int count, u8 *first, u8 *rest) +/* Assume a 7-bit address, which is reasonable for SMBus */ +static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) { - return i2c_smbus_partial_pec(0, count, first, rest); + /* The address will be sent first */ + u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); + pec = i2c_smbus_pec(pec, &addr, 1); + + /* The data buffer follows */ + return i2c_smbus_pec(pec, msg->buf, msg->len); } -/* Returns new "size" (transaction type) - Note that we convert byte to byte_data and byte_data to word_data - rather than invent new xxx_PEC transactions. */ -static int i2c_smbus_add_pec(u16 addr, u8 command, int size, - union i2c_smbus_data *data) +/* Used for write only transactions */ +static inline void i2c_smbus_add_pec(struct i2c_msg *msg) { - u8 buf[3]; - - buf[0] = addr << 1; - buf[1] = command; - switch(size) { - case I2C_SMBUS_BYTE: - data->byte = i2c_smbus_pec(2, buf, NULL); - size = I2C_SMBUS_BYTE_DATA; - break; - case I2C_SMBUS_BYTE_DATA: - buf[2] = data->byte; - data->word = buf[2] || - (i2c_smbus_pec(3, buf, NULL) << 8); - size = I2C_SMBUS_WORD_DATA; - break; - case I2C_SMBUS_WORD_DATA: - /* unsupported */ - break; - case I2C_SMBUS_BLOCK_DATA: - data->block[data->block[0] + 1] = - i2c_smbus_pec(2, buf, data->block); - size = I2C_SMBUS_BLOCK_DATA_PEC; - break; - } - return size; + msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); + msg->len++; } -static int i2c_smbus_check_pec(u16 addr, u8 command, int size, u8 partial, - union i2c_smbus_data *data) +/* Return <0 on CRC error + If there was a write before this read (most cases) we need to take the + partial CRC from the write part into account. + Note that this function does modify the message (we need to decrease the + message length to hide the CRC byte from the caller). */ +static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) { - u8 buf[3], rpec, cpec; + u8 rpec = msg->buf[--msg->len]; + cpec = i2c_smbus_msg_pec(cpec, msg); - buf[1] = command; - switch(size) { - case I2C_SMBUS_BYTE_DATA: - buf[0] = (addr << 1) | 1; - cpec = i2c_smbus_pec(2, buf, NULL); - rpec = data->byte; - break; - case I2C_SMBUS_WORD_DATA: - buf[0] = (addr << 1) | 1; - buf[2] = data->word & 0xff; - cpec = i2c_smbus_pec(3, buf, NULL); - rpec = data->word >> 8; - break; - case I2C_SMBUS_WORD_DATA_PEC: - /* unsupported */ - cpec = rpec = 0; - break; - case I2C_SMBUS_PROC_CALL_PEC: - /* unsupported */ - cpec = rpec = 0; - break; - case I2C_SMBUS_BLOCK_DATA_PEC: - buf[0] = (addr << 1); - buf[2] = (addr << 1) | 1; - cpec = i2c_smbus_pec(3, buf, data->block); - rpec = data->block[data->block[0] + 1]; - break; - case I2C_SMBUS_BLOCK_PROC_CALL_PEC: - buf[0] = (addr << 1) | 1; - rpec = i2c_smbus_partial_pec(partial, 1, - buf, data->block); - cpec = data->block[data->block[0] + 1]; - break; - default: - cpec = rpec = 0; - break; - } if (rpec != cpec) { pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", rpec, cpec); @@ -941,9 +896,8 @@ s32 i2c_smbus_read_byte(struct i2c_client *client) s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) { - union i2c_smbus_data data; /* only for PEC */ return i2c_smbus_xfer(client->adapter,client->addr,client->flags, - I2C_SMBUS_WRITE,value, I2C_SMBUS_BYTE,&data); + I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); } s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) @@ -1026,13 +980,14 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, need to use only one message; when reading, we need two. We initialize most things with sane defaults, to keep the code below somewhat simpler. */ - unsigned char msgbuf0[34]; - unsigned char msgbuf1[34]; + unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; + unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; int num = read_write == I2C_SMBUS_READ?2:1; struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, { addr, flags | I2C_M_RD, 0, msgbuf1 } }; int i; + u8 partial_pec = 0; msgbuf0[0] = command; switch(size) { @@ -1075,7 +1030,6 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, msgbuf0[2] = (data->word >> 8) & 0xff; break; case I2C_SMBUS_BLOCK_DATA: - case I2C_SMBUS_BLOCK_DATA_PEC: if (read_write == I2C_SMBUS_READ) { dev_err(&adapter->dev, "Block read not supported " "under I2C emulation!\n"); @@ -1088,23 +1042,20 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, data->block[0]); return -1; } - if(size == I2C_SMBUS_BLOCK_DATA_PEC) - (msg[0].len)++; - for (i = 1; i <= msg[0].len; i++) + for (i = 1; i < msg[0].len; i++) msgbuf0[i] = data->block[i-1]; } break; case I2C_SMBUS_BLOCK_PROC_CALL: - case I2C_SMBUS_BLOCK_PROC_CALL_PEC: dev_dbg(&adapter->dev, "Block process call not supported " "under I2C emulation!\n"); return -1; case I2C_SMBUS_I2C_BLOCK_DATA: if (read_write == I2C_SMBUS_READ) { - msg[1].len = I2C_SMBUS_I2C_BLOCK_MAX; + msg[1].len = I2C_SMBUS_BLOCK_MAX; } else { msg[0].len = data->block[0] + 1; - if (msg[0].len > I2C_SMBUS_I2C_BLOCK_MAX + 1) { + if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with " "invalid block write size (%d)\n", data->block[0]); @@ -1120,9 +1071,30 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, return -1; } + i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK + && size != I2C_SMBUS_I2C_BLOCK_DATA); + if (i) { + /* Compute PEC if first message is a write */ + if (!(msg[0].flags & I2C_M_RD)) { + if (num == 1) /* Write only */ + i2c_smbus_add_pec(&msg[0]); + else /* Write followed by read */ + partial_pec = i2c_smbus_msg_pec(0, &msg[0]); + } + /* Ask for PEC if last message is a read */ + if (msg[num-1].flags & I2C_M_RD) + msg[num-1].len++; + } + if (i2c_transfer(adapter, msg, num) < 0) return -1; + /* Check PEC if last message is a read */ + if (i && (msg[num-1].flags & I2C_M_RD)) { + if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0) + return -1; + } + if (read_write == I2C_SMBUS_READ) switch(size) { case I2C_SMBUS_BYTE: @@ -1137,8 +1109,8 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, break; case I2C_SMBUS_I2C_BLOCK_DATA: /* fixed at 32 for now */ - data->block[0] = I2C_SMBUS_I2C_BLOCK_MAX; - for (i = 0; i < I2C_SMBUS_I2C_BLOCK_MAX; i++) + data->block[0] = I2C_SMBUS_BLOCK_MAX; + for (i = 0; i < I2C_SMBUS_BLOCK_MAX; i++) data->block[i+1] = msgbuf1[i]; break; } @@ -1151,28 +1123,8 @@ s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags, union i2c_smbus_data * data) { s32 res; - int swpec = 0; - u8 partial = 0; flags &= I2C_M_TEN | I2C_CLIENT_PEC; - if((flags & I2C_CLIENT_PEC) && - !(i2c_check_functionality(adapter, I2C_FUNC_SMBUS_HWPEC_CALC))) { - swpec = 1; - if(read_write == I2C_SMBUS_READ && - size == I2C_SMBUS_BLOCK_DATA) - size = I2C_SMBUS_BLOCK_DATA_PEC; - else if(size == I2C_SMBUS_PROC_CALL) - size = I2C_SMBUS_PROC_CALL_PEC; - else if(size == I2C_SMBUS_BLOCK_PROC_CALL) { - i2c_smbus_add_pec(addr, command, - I2C_SMBUS_BLOCK_DATA, data); - partial = data->block[data->block[0] + 1]; - size = I2C_SMBUS_BLOCK_PROC_CALL_PEC; - } else if(read_write == I2C_SMBUS_WRITE && - size != I2C_SMBUS_QUICK && - size != I2C_SMBUS_I2C_BLOCK_DATA) - size = i2c_smbus_add_pec(addr, command, size, data); - } if (adapter->algo->smbus_xfer) { down(&adapter->bus_lock); @@ -1183,13 +1135,6 @@ s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags, res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write, command,size,data); - if(res >= 0 && swpec && - size != I2C_SMBUS_QUICK && size != I2C_SMBUS_I2C_BLOCK_DATA && - (read_write == I2C_SMBUS_READ || size == I2C_SMBUS_PROC_CALL_PEC || - size == I2C_SMBUS_BLOCK_PROC_CALL_PEC)) { - if(i2c_smbus_check_pec(addr, command, size, partial, data)) - return -1; - } return res; } |