diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-isch.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-isch.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-isch.c b/drivers/i2c/busses/i2c-isch.c index f90a6057508d..8c38aaa7417c 100644 --- a/drivers/i2c/busses/i2c-isch.c +++ b/drivers/i2c/busses/i2c-isch.c @@ -40,6 +40,7 @@ /* SCH SMBus address offsets */ #define SMBHSTCNT (0 + sch_smba) #define SMBHSTSTS (1 + sch_smba) +#define SMBHSTCLK (2 + sch_smba) #define SMBHSTADD (4 + sch_smba) /* TSA */ #define SMBHSTCMD (5 + sch_smba) #define SMBHSTDAT0 (6 + sch_smba) @@ -58,6 +59,9 @@ static unsigned short sch_smba; static struct i2c_adapter sch_adapter; +static int backbone_speed = 33000; /* backbone speed in kHz */ +module_param(backbone_speed, int, S_IRUSR | S_IWUSR); +MODULE_PARM_DESC(backbone_speed, "Backbone speed in kHz, (default = 33000)"); /* * Start the i2c transaction -- the i2c_access will prepare the transaction @@ -156,6 +160,19 @@ static s32 sch_access(struct i2c_adapter *adap, u16 addr, dev_dbg(&sch_adapter.dev, "SMBus busy (%02x)\n", temp); return -EAGAIN; } + temp = inw(SMBHSTCLK); + if (!temp) { + /* + * We can't determine if we have 33 or 25 MHz clock for + * SMBus, so expect 33 MHz and calculate a bus clock of + * 100 kHz. If we actually run at 25 MHz the bus will be + * run ~75 kHz instead which should do no harm. + */ + dev_notice(&sch_adapter.dev, + "Clock divider unitialized. Setting defaults\n"); + outw(backbone_speed / (4 * 100), SMBHSTCLK); + } + dev_dbg(&sch_adapter.dev, "access size: %d %s\n", size, (read_write)?"READ":"WRITE"); switch (size) { @@ -249,7 +266,7 @@ static struct i2c_adapter sch_adapter = { .algo = &smbus_algorithm, }; -static int __devinit smbus_sch_probe(struct platform_device *dev) +static int smbus_sch_probe(struct platform_device *dev) { struct resource *res; int retval; @@ -284,7 +301,7 @@ static int __devinit smbus_sch_probe(struct platform_device *dev) return retval; } -static int __devexit smbus_sch_remove(struct platform_device *pdev) +static int smbus_sch_remove(struct platform_device *pdev) { struct resource *res; if (sch_smba) { @@ -303,7 +320,7 @@ static struct platform_driver smbus_sch_driver = { .owner = THIS_MODULE, }, .probe = smbus_sch_probe, - .remove = __devexit_p(smbus_sch_remove), + .remove = smbus_sch_remove, }; module_platform_driver(smbus_sch_driver); |