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Diffstat (limited to 'drivers/i2c/busses/i2c-tiny-usb.c')
-rw-r--r--drivers/i2c/busses/i2c-tiny-usb.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c
index e29b6d5ba8ef..b5b1bbf37d3c 100644
--- a/drivers/i2c/busses/i2c-tiny-usb.c
+++ b/drivers/i2c/busses/i2c-tiny-usb.c
@@ -31,11 +31,13 @@
 #define CMD_I2C_IO_BEGIN	(1<<0)
 #define CMD_I2C_IO_END		(1<<1)
 
-/* i2c bit delay, default is 10us -> 100kHz */
+/* i2c bit delay, default is 10us -> 100kHz max
+   (in practice, due to additional delays in the i2c bitbanging
+   code this results in a i2c clock of about 50kHz) */
 static unsigned short delay = 10;
 module_param(delay, ushort, 0);
-MODULE_PARM_DESC(delay, "bit delay in microseconds, "
-		 "e.g. 10 for 100kHz (default is 100kHz)");
+MODULE_PARM_DESC(delay, "bit delay in microseconds "
+		 "(default is 10us for 100kHz max)");
 
 static int usb_read(struct i2c_adapter *adapter, int cmd,
 		    int value, int index, void *data, int len);
@@ -137,7 +139,7 @@ static const struct i2c_algorithm usb_algorithm = {
  * Future Technology Devices International Ltd., later a pair was
  * bought from EZPrototypes
  */
-static struct usb_device_id i2c_tiny_usb_table [] = {
+static const struct usb_device_id i2c_tiny_usb_table[] = {
 	{ USB_DEVICE(0x0403, 0xc631) },   /* FTDI */
 	{ USB_DEVICE(0x1c40, 0x0534) },   /* EZPrototypes */
 	{ }                               /* Terminating entry */