Commit 9fc1427a authored by Cornelia Huck's avatar Cornelia Huck Committed by Linus Torvalds

[PATCH] s390: cio documentation

Synchronize documentation with current interface.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent af6c8eed
......@@ -56,12 +56,16 @@ read_dev_chars()
read device characteristics
read_conf_data()
read_conf_data_lpm()
read configuration data.
ccw_device_get_ciw()
get commands from extended sense data.
ccw_device_start()
ccw_device_start_timeout()
ccw_device_start_key()
ccw_device_start_key_timeout()
initiate an I/O request.
ccw_device_resume()
......@@ -197,19 +201,21 @@ The read_dev_chars() function returns :
operational.
read_conf_data() - Read Configuration Data
read_conf_data(), read_conf_data_lpm() - Read Configuration Data
Retrieve the device dependent configuration data. Please have a look at your
device dependent I/O commands for the device specific layout of the node
descriptor elements.
descriptor elements. read_conf_data_lpm() will retrieve the configuration data
for a specific path.
The function is meant to be called with an irq handler in place; that is,
The function is meant to be called with the device already enabled; that is,
at earliest during set_online() processing.
The function may be called enabled or disabled, but the device must not be
locked
int read_conf_data(struct ccw_device, void **buffer, int *length, __u8 lpm);
int read_conf_data(struct ccw_device, void **buffer, int *length);
int read_conf_data_lpm(struct ccw_device, void **buffer, int *length, __u8 lpm);
cdev - the ccw_device the data is requested for.
buffer - Pointer to a buffer pointer. The read_conf_data() routine
......@@ -263,6 +269,25 @@ int ccw_device_start(struct ccw_device *cdev,
unsigned long intparm,
__u8 lpm,
unsigned long flags);
int ccw_device_start_timeout(struct ccw_device *cdev,
struct ccw1 *cpa,
unsigned long intparm,
__u8 lpm,
unsigned long flags,
int expires);
int ccw_device_start_key(struct ccw_device *cdev,
struct ccw1 *cpa,
unsigned long intparm,
__u8 lpm,
__u8 key,
unsigned long flags);
int ccw_device_start_key_timeout(struct ccw_device *cdev,
struct ccw1 *cpa,
unsigned long intparm,
__u8 lpm,
__u8 key,
unsigned long flags,
int expires);
cdev : ccw_device the I/O is destined for
cpa : logical start address of channel program
......@@ -272,7 +297,12 @@ user_intparm : user specific interrupt information; will be presented
particular I/O request.
lpm : defines the channel path to be used for a specific I/O
request. A value of 0 will make cio use the opm.
key : the storage key to use for the I/O (useful for operating on a
storage with a storage key != default key)
flag : defines the action to be performed for I/O processing
expires : timeout value in jiffies. The common I/O layer will terminate
the running program after this and call the interrupt handler
with ERR_PTR(-ETIMEDOUT) as irb.
Possible flag values are :
......@@ -327,6 +357,13 @@ current (last) I/O request. In case of a delayed status notification no special
interrupt will be presented to indicate I/O completion as the I/O request was
never started, even though ccw_device_start() returned with successful completion.
The irb may contain an error value, and the device driver should check for this
first:
-ETIMEDOUT: the common I/O layer terminated the request after the specified
timeout value
-EIO: the common I/O layer terminated the request due to an error state
If the concurrent sense flag in the extended status word in the irb is set, the
field irb->scsw.count describes the numer of device specific sense bytes
available in the extended control word irb->scsw.ecw[0]. No device sensing by
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment