diff options
Diffstat (limited to 'drivers/s390/cio/device_ops.c')
| -rw-r--r-- | drivers/s390/cio/device_ops.c | 241 |
1 files changed, 211 insertions, 30 deletions
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c index 14eba854b155..7fd2dadc3297 100644 --- a/drivers/s390/cio/device_ops.c +++ b/drivers/s390/cio/device_ops.c @@ -25,6 +25,16 @@ #include "device.h" #include "chp.h" +/** + * ccw_device_set_options_mask() - set some options and unset the rest + * @cdev: device for which the options are to be set + * @flags: options to be set + * + * All flags specified in @flags are set, all flags not specified in @flags + * are cleared. + * Returns: + * %0 on success, -%EINVAL on an invalid flag combination. + */ int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags) { /* @@ -40,6 +50,15 @@ int ccw_device_set_options_mask(struct ccw_device *cdev, unsigned long flags) return 0; } +/** + * ccw_device_set_options() - set some options + * @cdev: device for which the options are to be set + * @flags: options to be set + * + * All flags specified in @flags are set, the remainder is left untouched. + * Returns: + * %0 on success, -%EINVAL if an invalid flag combination would ensue. + */ int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags) { /* @@ -59,6 +78,13 @@ int ccw_device_set_options(struct ccw_device *cdev, unsigned long flags) return 0; } +/** + * ccw_device_clear_options() - clear some options + * @cdev: device for which the options are to be cleared + * @flags: options to be cleared + * + * All flags specified in @flags are cleared, the remainder is left untouched. + */ void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags) { cdev->private->options.fast &= (flags & CCWDEV_EARLY_NOTIFICATION) == 0; @@ -67,8 +93,22 @@ void ccw_device_clear_options(struct ccw_device *cdev, unsigned long flags) cdev->private->options.force &= (flags & CCWDEV_ALLOW_FORCE) == 0; } -int -ccw_device_clear(struct ccw_device *cdev, unsigned long intparm) +/** + * ccw_device_clear() - terminate I/O request processing + * @cdev: target ccw device + * @intparm: interruption parameter; value is only used if no I/O is + * outstanding, otherwise the intparm associated with the I/O request + * is returned + * + * ccw_device_clear() calls csch on @cdev's subchannel. + * Returns: + * %0 on success, + * -%ENODEV on device not operational, + * -%EINVAL on invalid device state. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm) { struct subchannel *sch; int ret; @@ -89,10 +129,33 @@ ccw_device_clear(struct ccw_device *cdev, unsigned long intparm) return ret; } -int -ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa, - unsigned long intparm, __u8 lpm, __u8 key, - unsigned long flags) +/** + * ccw_device_start_key() - start a s390 channel program with key + * @cdev: target ccw device + * @cpa: logical start address of channel program + * @intparm: user specific interruption parameter; will be presented back to + * @cdev's interrupt handler. Allows a device driver to associate + * the interrupt with a 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: storage key to be used for the I/O + * @flags: additional flags; defines the action to be performed for I/O + * processing. + * + * Start a S/390 channel program. When the interrupt arrives, the + * IRQ handler is called, either immediately, delayed (dev-end missing, + * or sense required) or never (no IRQ handler registered). + * Returns: + * %0, if the operation was successful; + * -%EBUSY, if the device is busy, or status pending; + * -%EACCES, if no path specified in @lpm is operational; + * -%ENODEV, if the device is not operational. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa, + unsigned long intparm, __u8 lpm, __u8 key, + unsigned long flags) { struct subchannel *sch; int ret; @@ -135,11 +198,38 @@ ccw_device_start_key(struct ccw_device *cdev, struct ccw1 *cpa, return ret; } - -int -ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa, - unsigned long intparm, __u8 lpm, __u8 key, - unsigned long flags, int expires) +/** + * ccw_device_start_timeout_key() - start a s390 channel program with timeout and key + * @cdev: target ccw device + * @cpa: logical start address of channel program + * @intparm: user specific interruption parameter; will be presented back to + * @cdev's interrupt handler. Allows a device driver to associate + * the interrupt with a 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: storage key to be used for the I/O + * @flags: additional flags; defines the action to be performed for I/O + * processing. + * @expires: timeout value in jiffies + * + * Start a S/390 channel program. When the interrupt arrives, the + * IRQ handler is called, either immediately, delayed (dev-end missing, + * or sense required) or never (no IRQ handler registered). + * This function notifies the device driver if the channel program has not + * completed during the time specified by @expires. If a timeout occurs, the + * channel program is terminated via xsch, hsch or csch, and the device's + * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT). + * Returns: + * %0, if the operation was successful; + * -%EBUSY, if the device is busy, or status pending; + * -%EACCES, if no path specified in @lpm is operational; + * -%ENODEV, if the device is not operational. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa, + unsigned long intparm, __u8 lpm, __u8 key, + unsigned long flags, int expires) { int ret; @@ -152,18 +242,67 @@ ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa, return ret; } -int -ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa, - unsigned long intparm, __u8 lpm, unsigned long flags) +/** + * ccw_device_start() - start a s390 channel program + * @cdev: target ccw device + * @cpa: logical start address of channel program + * @intparm: user specific interruption parameter; will be presented back to + * @cdev's interrupt handler. Allows a device driver to associate + * the interrupt with a 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. + * @flags: additional flags; defines the action to be performed for I/O + * processing. + * + * Start a S/390 channel program. When the interrupt arrives, the + * IRQ handler is called, either immediately, delayed (dev-end missing, + * or sense required) or never (no IRQ handler registered). + * Returns: + * %0, if the operation was successful; + * -%EBUSY, if the device is busy, or status pending; + * -%EACCES, if no path specified in @lpm is operational; + * -%ENODEV, if the device is not operational. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_start(struct ccw_device *cdev, struct ccw1 *cpa, + unsigned long intparm, __u8 lpm, unsigned long flags) { return ccw_device_start_key(cdev, cpa, intparm, lpm, PAGE_DEFAULT_KEY, flags); } -int -ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa, - unsigned long intparm, __u8 lpm, unsigned long flags, - int expires) +/** + * ccw_device_start_timeout() - start a s390 channel program with timeout + * @cdev: target ccw device + * @cpa: logical start address of channel program + * @intparm: user specific interruption parameter; will be presented back to + * @cdev's interrupt handler. Allows a device driver to associate + * the interrupt with a 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. + * @flags: additional flags; defines the action to be performed for I/O + * processing. + * @expires: timeout value in jiffies + * + * Start a S/390 channel program. When the interrupt arrives, the + * IRQ handler is called, either immediately, delayed (dev-end missing, + * or sense required) or never (no IRQ handler registered). + * This function notifies the device driver if the channel program has not + * completed during the time specified by @expires. If a timeout occurs, the + * channel program is terminated via xsch, hsch or csch, and the device's + * interrupt handler will be called with an irb containing ERR_PTR(-%ETIMEDOUT). + * Returns: + * %0, if the operation was successful; + * -%EBUSY, if the device is busy, or status pending; + * -%EACCES, if no path specified in @lpm is operational; + * -%ENODEV, if the device is not operational. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa, + unsigned long intparm, __u8 lpm, + unsigned long flags, int expires) { return ccw_device_start_timeout_key(cdev, cpa, intparm, lpm, PAGE_DEFAULT_KEY, flags, @@ -171,8 +310,23 @@ ccw_device_start_timeout(struct ccw_device *cdev, struct ccw1 *cpa, } -int -ccw_device_halt(struct ccw_device *cdev, unsigned long intparm) +/** + * ccw_device_halt() - halt I/O request processing + * @cdev: target ccw device + * @intparm: interruption parameter; value is only used if no I/O is + * outstanding, otherwise the intparm associated with the I/O request + * is returned + * + * ccw_device_halt() calls hsch on @cdev's subchannel. + * Returns: + * %0 on success, + * -%ENODEV on device not operational, + * -%EINVAL on invalid device state, + * -%EBUSY on device busy or interrupt pending. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm) { struct subchannel *sch; int ret; @@ -193,8 +347,20 @@ ccw_device_halt(struct ccw_device *cdev, unsigned long intparm) return ret; } -int -ccw_device_resume(struct ccw_device *cdev) +/** + * ccw_device_resume() - resume channel program execution + * @cdev: target ccw device + * + * ccw_device_resume() calls rsch on @cdev's subchannel. + * Returns: + * %0 on success, + * -%ENODEV on device not operational, + * -%EINVAL on invalid device state, + * -%EBUSY on device busy or interrupt pending. + * Context: + * Interrupts disabled, ccw device lock held + */ +int ccw_device_resume(struct ccw_device *cdev) { struct subchannel *sch; @@ -260,11 +426,21 @@ ccw_device_call_handler(struct ccw_device *cdev) return 1; } -/* - * Search for CIW command in extended sense data. +/** + * ccw_device_get_ciw() - Search for CIW command in extended sense data. + * @cdev: ccw device to inspect + * @ct: command type to look for + * + * During SenseID, command information words (CIWs) describing special + * commands available to the device may have been stored in the extended + * sense data. This function searches for CIWs of a specified command + * type in the extended sense data. + * Returns: + * %NULL if no extended sense data has been stored or if no CIW of the + * specified command type could be found, + * else a pointer to the CIW of the specified command type. */ -struct ciw * -ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct) +struct ciw *ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct) { int ciw_cnt; @@ -276,8 +452,14 @@ ccw_device_get_ciw(struct ccw_device *cdev, __u32 ct) return NULL; } -__u8 -ccw_device_get_path_mask(struct ccw_device *cdev) +/** + * ccw_device_get_path_mask() - get currently available paths + * @cdev: ccw device to be queried + * Returns: + * %0 if no subchannel for the device is available, + * else the mask of currently available paths for the ccw device's subchannel. + */ +__u8 ccw_device_get_path_mask(struct ccw_device *cdev) { struct subchannel *sch; @@ -357,8 +539,7 @@ out_unlock: return ret; } -void * -ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no) +void *ccw_device_get_chp_desc(struct ccw_device *cdev, int chp_no) { struct subchannel *sch; struct chp_id chpid; |
