libata: identify and init ZPODD devices

The ODD can be enabled for ZPODD if the following three conditions are
satisfied:
1 The ODD supports device attention;
2 The platform can runtime power off the ODD through ACPI;
3 The ODD is either slot type or drawer type.
For such ODDs, zpodd_init is called and a new structure is allocated for
it to store ZPODD related stuffs.

And the zpodd_dev_enabled function is used to test if ZPODD is currently
enabled for this ODD.

A new config CONFIG_SATA_ZPODD is added to selectively build ZPODD code.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Aaron Lu 2013-01-15 17:20:58 +08:00 committed by Jeff Garzik
parent 1757d902b0
commit afe7595118
8 changed files with 170 additions and 1 deletions

View file

@ -58,6 +58,19 @@ config ATA_ACPI
You can disable this at kernel boot time by using the
option libata.noacpi=1
config SATA_ZPODD
bool "SATA Zero Power ODD Support"
depends on ATA_ACPI
default n
help
This option adds support for SATA ZPODD. It requires both
ODD and the platform support, and if enabled, will automatically
power on/off the ODD when certain condition is satisfied. This
does not impact user's experience of the ODD, only power is saved
when ODD is not in use(i.e. no disc inside).
If unsure, say N.
config SATA_PMP
bool "SATA Port Multiplier support"
default y

View file

@ -107,3 +107,4 @@ libata-y := libata-core.o libata-scsi.o libata-eh.o libata-transport.o
libata-$(CONFIG_ATA_SFF) += libata-sff.o
libata-$(CONFIG_SATA_PMP) += libata-pmp.o
libata-$(CONFIG_ATA_ACPI) += libata-acpi.o
libata-$(CONFIG_SATA_ZPODD) += libata-zpodd.o

View file

@ -2401,8 +2401,10 @@ int ata_dev_configure(struct ata_device *dev)
dma_dir_string = ", DMADIR";
}
if (ata_id_has_da(dev->id))
if (ata_id_has_da(dev->id)) {
dev->flags |= ATA_DFLAG_DA;
zpodd_init(dev);
}
/* print device info to dmesg */
if (ata_msg_drv(ap) && print_info)

View file

@ -3755,6 +3755,8 @@ static void ata_scsi_remove_dev(struct ata_device *dev)
mutex_lock(&ap->scsi_host->scan_mutex);
spin_lock_irqsave(ap->lock, flags);
if (zpodd_dev_enabled(dev))
zpodd_exit(dev);
ata_acpi_unbind(dev);
/* clearing dev->sdev is protected by host lock */

100
drivers/ata/libata-zpodd.c Normal file
View file

@ -0,0 +1,100 @@
#include <linux/libata.h>
#include <linux/cdrom.h>
#include "libata.h"
enum odd_mech_type {
ODD_MECH_TYPE_SLOT,
ODD_MECH_TYPE_DRAWER,
ODD_MECH_TYPE_UNSUPPORTED,
};
struct zpodd {
enum odd_mech_type mech_type; /* init during probe, RO afterwards */
struct ata_device *dev;
};
/* Per the spec, only slot type and drawer type ODD can be supported */
static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
{
char buf[16];
unsigned int ret;
struct rm_feature_desc *desc = (void *)(buf + 8);
struct ata_taskfile tf = {};
char cdb[] = { GPCMD_GET_CONFIGURATION,
2, /* only 1 feature descriptor requested */
0, 3, /* 3, removable medium feature */
0, 0, 0,/* reserved */
0, sizeof(buf),
0, 0, 0,
};
tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
tf.command = ATA_CMD_PACKET;
tf.protocol = ATAPI_PROT_PIO;
tf.lbam = sizeof(buf);
ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
buf, sizeof(buf), 0);
if (ret)
return ODD_MECH_TYPE_UNSUPPORTED;
if (be16_to_cpu(desc->feature_code) != 3)
return ODD_MECH_TYPE_UNSUPPORTED;
if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1)
return ODD_MECH_TYPE_SLOT;
else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1)
return ODD_MECH_TYPE_DRAWER;
else
return ODD_MECH_TYPE_UNSUPPORTED;
}
static bool odd_can_poweroff(struct ata_device *ata_dev)
{
acpi_handle handle;
acpi_status status;
struct acpi_device *acpi_dev;
handle = ata_dev_acpi_handle(ata_dev);
if (!handle)
return false;
status = acpi_bus_get_device(handle, &acpi_dev);
if (ACPI_FAILURE(status))
return false;
return acpi_device_can_poweroff(acpi_dev);
}
void zpodd_init(struct ata_device *dev)
{
enum odd_mech_type mech_type;
struct zpodd *zpodd;
if (dev->zpodd)
return;
if (!odd_can_poweroff(dev))
return;
mech_type = zpodd_get_mech_type(dev);
if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
return;
zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
if (!zpodd)
return;
zpodd->mech_type = mech_type;
zpodd->dev = dev;
dev->zpodd = zpodd;
}
void zpodd_exit(struct ata_device *dev)
{
kfree(dev->zpodd);
dev->zpodd = NULL;
}

View file

@ -230,4 +230,18 @@ static inline void ata_sff_exit(void)
{ }
#endif /* CONFIG_ATA_SFF */
/* libata-zpodd.c */
#ifdef CONFIG_SATA_ZPODD
void zpodd_init(struct ata_device *dev);
void zpodd_exit(struct ata_device *dev);
static inline bool zpodd_dev_enabled(struct ata_device *dev)
{
return dev->zpodd != NULL;
}
#else /* CONFIG_SATA_ZPODD */
static inline void zpodd_init(struct ata_device *dev) {}
static inline void zpodd_exit(struct ata_device *dev) {}
static inline bool zpodd_dev_enabled(struct ata_device *dev) { return false; }
#endif /* CONFIG_SATA_ZPODD */
#endif /* __LIBATA_H__ */

View file

@ -620,6 +620,9 @@ struct ata_device {
#ifdef CONFIG_ATA_ACPI
union acpi_object *gtf_cache;
unsigned int gtf_filter;
#endif
#ifdef CONFIG_SATA_ZPODD
void *zpodd;
#endif
struct device tdev;
/* n_sector is CLEAR_BEGIN, read comment above CLEAR_BEGIN */

View file

@ -908,5 +908,39 @@ struct mode_page_header {
__be16 desc_length;
};
/* removable medium feature descriptor */
struct rm_feature_desc {
__be16 feature_code;
#if defined(__BIG_ENDIAN_BITFIELD)
__u8 reserved1:2;
__u8 feature_version:4;
__u8 persistent:1;
__u8 curr:1;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
__u8 curr:1;
__u8 persistent:1;
__u8 feature_version:4;
__u8 reserved1:2;
#endif
__u8 add_len;
#if defined(__BIG_ENDIAN_BITFIELD)
__u8 mech_type:3;
__u8 load:1;
__u8 eject:1;
__u8 pvnt_jmpr:1;
__u8 dbml:1;
__u8 lock:1;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
__u8 lock:1;
__u8 dbml:1;
__u8 pvnt_jmpr:1;
__u8 eject:1;
__u8 load:1;
__u8 mech_type:3;
#endif
__u8 reserved2;
__u8 reserved3;
__u8 reserved4;
};
#endif /* _UAPI_LINUX_CDROM_H */