[SCSI] libsas: Add a sysfs knob to enable/disable a phy

This patch lets a user arbitrarily enable or disable a phy via sysfs.
Potential applications include shutting down a phy to replace one
lane of wide port, and (more importantly) providing a method for the
libata SATL to control the phy.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
Darrick J. Wong 2007-01-11 14:14:57 -08:00 committed by James Bottomley
parent b218a0d8e2
commit acbf167d4a
5 changed files with 90 additions and 2 deletions

View File

@ -146,6 +146,36 @@ static int sas_get_linkerrors(struct sas_phy *phy)
return sas_smp_get_phy_events(phy);
}
int sas_phy_enable(struct sas_phy *phy, int enable)
{
int ret;
enum phy_func command;
if (enable)
command = PHY_FUNC_LINK_RESET;
else
command = PHY_FUNC_DISABLE;
if (scsi_is_sas_phy_local(phy)) {
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
struct sas_internal *i =
to_sas_internal(sas_ha->core.shost->transportt);
if (!enable) {
sas_phy_disconnected(asd_phy);
sas_ha->notify_phy_event(asd_phy, PHYE_LOSS_OF_SIGNAL);
}
ret = i->dft->lldd_control_phy(asd_phy, command, NULL);
} else {
struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
ret = sas_smp_phy_control(ddev, phy->number, command, NULL);
}
return ret;
}
int sas_phy_reset(struct sas_phy *phy, int hard_reset)
{
int ret;
@ -172,8 +202,8 @@ int sas_phy_reset(struct sas_phy *phy, int hard_reset)
return ret;
}
static int sas_set_phy_speed(struct sas_phy *phy,
struct sas_phy_linkrates *rates)
int sas_set_phy_speed(struct sas_phy *phy,
struct sas_phy_linkrates *rates)
{
int ret;
@ -212,6 +242,7 @@ static int sas_set_phy_speed(struct sas_phy *phy,
}
static struct sas_function_template sft = {
.phy_enable = sas_phy_enable,
.phy_reset = sas_phy_reset,
.set_phy_speed = sas_set_phy_speed,
.get_linkerrors = sas_get_linkerrors,

View File

@ -875,3 +875,4 @@ EXPORT_SYMBOL_GPL(sas_change_queue_type);
EXPORT_SYMBOL_GPL(sas_bios_param);
EXPORT_SYMBOL_GPL(sas_task_abort);
EXPORT_SYMBOL_GPL(sas_phy_reset);
EXPORT_SYMBOL_GPL(sas_phy_enable);

View File

@ -336,6 +336,51 @@ show_sas_device_type(struct class_device *cdev, char *buf)
}
static CLASS_DEVICE_ATTR(device_type, S_IRUGO, show_sas_device_type, NULL);
static ssize_t do_sas_phy_enable(struct class_device *cdev,
size_t count, int enable)
{
struct sas_phy *phy = transport_class_to_phy(cdev);
struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
struct sas_internal *i = to_sas_internal(shost->transportt);
int error;
error = i->f->phy_enable(phy, enable);
if (error)
return error;
phy->enabled = enable;
return count;
};
static ssize_t store_sas_phy_enable(struct class_device *cdev,
const char *buf, size_t count)
{
if (count < 1)
return -EINVAL;
switch (buf[0]) {
case '0':
do_sas_phy_enable(cdev, count, 0);
break;
case '1':
do_sas_phy_enable(cdev, count, 1);
break;
default:
return -EINVAL;
}
return count;
}
static ssize_t show_sas_phy_enable(struct class_device *cdev, char *buf)
{
struct sas_phy *phy = transport_class_to_phy(cdev);
return snprintf(buf, 20, "%d", phy->enabled);
}
static CLASS_DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, show_sas_phy_enable,
store_sas_phy_enable);
static ssize_t do_sas_phy_reset(struct class_device *cdev,
size_t count, int hard_reset)
{
@ -435,6 +480,7 @@ struct sas_phy *sas_phy_alloc(struct device *parent, int number)
return NULL;
phy->number = number;
phy->enabled = 1;
device_initialize(&phy->dev);
phy->dev.parent = get_device(parent);
@ -1389,6 +1435,10 @@ static int sas_user_scan(struct Scsi_Host *shost, uint channel,
SETUP_TEMPLATE_RW(phy_attrs, field, S_IRUGO | S_IWUSR, 1, \
!i->f->set_phy_speed, S_IRUGO)
#define SETUP_OPTIONAL_PHY_ATTRIBUTE_RW(field, func) \
SETUP_TEMPLATE_RW(phy_attrs, field, S_IRUGO | S_IWUSR, 1, \
!i->f->func, S_IRUGO)
#define SETUP_PORT_ATTRIBUTE(field) \
SETUP_TEMPLATE(port_attrs, field, S_IRUGO, 1)
@ -1479,6 +1529,7 @@ sas_attach_transport(struct sas_function_template *ft)
SETUP_PHY_ATTRIBUTE(phy_reset_problem_count);
SETUP_OPTIONAL_PHY_ATTRIBUTE_WRONLY(link_reset, phy_reset);
SETUP_OPTIONAL_PHY_ATTRIBUTE_WRONLY(hard_reset, phy_reset);
SETUP_OPTIONAL_PHY_ATTRIBUTE_RW(enable, phy_enable);
i->phy_attrs[count] = NULL;
count = 0;

View File

@ -614,6 +614,9 @@ struct sas_domain_function_template {
extern int sas_register_ha(struct sas_ha_struct *);
extern int sas_unregister_ha(struct sas_ha_struct *);
int sas_set_phy_speed(struct sas_phy *phy,
struct sas_phy_linkrates *rates);
int sas_phy_enable(struct sas_phy *phy, int enabled);
int sas_phy_reset(struct sas_phy *phy, int hard_reset);
extern int sas_queuecommand(struct scsi_cmnd *,
void (*scsi_done)(struct scsi_cmnd *));

View File

@ -54,6 +54,7 @@ struct sas_identify {
struct sas_phy {
struct device dev;
int number;
int enabled;
/* phy identification */
struct sas_identify identify;
@ -163,6 +164,7 @@ struct sas_function_template {
int (*get_enclosure_identifier)(struct sas_rphy *, u64 *);
int (*get_bay_identifier)(struct sas_rphy *);
int (*phy_reset)(struct sas_phy *, int);
int (*phy_enable)(struct sas_phy *, int);
int (*set_phy_speed)(struct sas_phy *, struct sas_phy_linkrates *);
};