| Message ID | 1352443922-13734-4-git-send-email-aaron.lu@intel.com |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
Hello, On Fri, Nov 09, 2012 at 02:51:55PM +0800, Aaron Lu wrote: > void ata_acpi_unbind(struct ata_device *dev) > { > + if (zpodd_dev_enabled(dev)) > + zpodd_deinit(dev); Maybe zpodd_exit() instead? > +void zpodd_init(struct ata_device *dev) > +{ > + int ret; > + struct zpodd *zpodd; > + > + if (dev->private_data) > + return; > + > + if (!device_can_poweroff(dev)) > + return; > + > + if ((ret = check_loading_mechanism(dev)) == -ENODEV) > + return; > + > + zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL); > + if (!zpodd) > + return; > + > + if (ret) > + zpodd->drawer = true; > + else > + zpodd->slot = true; > + > + zpodd->dev = dev; > + dev->private_data = zpodd; I don't think you're supposed to use dev->private_data from libata core layer. Just add a new field. Nobody cares about adding 8 more bytes to struct ata_device and spending 8 more bytes is way better than muddying the ownership of ->private_data. > +/* libata-zpodd.c */ > +#ifdef CONFIG_SATA_ZPODD > +void zpodd_init(struct ata_device *dev); > +void zpodd_deinit(struct ata_device *dev); > +static inline bool zpodd_dev_enabled(struct ata_device *dev) > +{ > + if (dev->flags & ATA_DFLAG_DA && dev->private_data) > + return true; > + else > + return false; > +} And this gets completely wrong. What if the device supports DA and low level driver makes use of ->private_data? Thanks.
On 11/13/2012 02:53 AM, Tejun Heo wrote: > Hello, > > On Fri, Nov 09, 2012 at 02:51:55PM +0800, Aaron Lu wrote: >> void ata_acpi_unbind(struct ata_device *dev) >> { >> + if (zpodd_dev_enabled(dev)) >> + zpodd_deinit(dev); > > Maybe zpodd_exit() instead? OK. > >> +void zpodd_init(struct ata_device *dev) >> +{ >> + int ret; >> + struct zpodd *zpodd; >> + >> + if (dev->private_data) >> + return; >> + >> + if (!device_can_poweroff(dev)) >> + return; >> + >> + if ((ret = check_loading_mechanism(dev)) == -ENODEV) >> + return; >> + >> + zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL); >> + if (!zpodd) >> + return; >> + >> + if (ret) >> + zpodd->drawer = true; >> + else >> + zpodd->slot = true; >> + >> + zpodd->dev = dev; >> + dev->private_data = zpodd; > > I don't think you're supposed to use dev->private_data from libata > core layer. Just add a new field. Nobody cares about adding 8 more > bytes to struct ata_device and spending 8 more bytes is way better > than muddying the ownership of ->private_data. OK. And just out of curiosity, who's supposed to use device's private_data? I didn't find any user for ata_device's private_data in libata. > >> +/* libata-zpodd.c */ >> +#ifdef CONFIG_SATA_ZPODD >> +void zpodd_init(struct ata_device *dev); >> +void zpodd_deinit(struct ata_device *dev); >> +static inline bool zpodd_dev_enabled(struct ata_device *dev) >> +{ >> + if (dev->flags & ATA_DFLAG_DA && dev->private_data) >> + return true; >> + else >> + return false; >> +} > > And this gets completely wrong. What if the device supports DA and > low level driver makes use of ->private_data? I didn't find any user of ata_device's private_data, so I used it for ZPODD. But if this is dangerous, I'll use a new field. Thanks, Aaron -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hello, Aaron. On Wed, Nov 14, 2012 at 09:32:27AM +0800, Aaron Lu wrote: > > I don't think you're supposed to use dev->private_data from libata > > core layer. Just add a new field. Nobody cares about adding 8 more > > bytes to struct ata_device and spending 8 more bytes is way better > > than muddying the ownership of ->private_data. > > OK. > And just out of curiosity, who's supposed to use device's private_data? > I didn't find any user for ata_device's private_data in libata. All the ->private_data fields are to be used by low level drivers (ahci, ata_piix, pata_via...). Given the twisted nature of ATA devices, it's a bit surprising that no driver yet found a need for ata_dev->private_data. For most SATA controllers, port to device is one to one so maybe ap->private_data is enough. > > And this gets completely wrong. What if the device supports DA and > > low level driver makes use of ->private_data? > > I didn't find any user of ata_device's private_data, so I used it for > ZPODD. But if this is dangerous, I'll use a new field. As there currently is no other user, it won't break anything but yeah please add a properly typed and named field. Thanks.
On 11/18/2012 10:38 PM, Tejun Heo wrote: > Hello, Aaron. Hi, > > On Wed, Nov 14, 2012 at 09:32:27AM +0800, Aaron Lu wrote: >>> I don't think you're supposed to use dev->private_data from libata >>> core layer. Just add a new field. Nobody cares about adding 8 more >>> bytes to struct ata_device and spending 8 more bytes is way better >>> than muddying the ownership of ->private_data. >> >> OK. >> And just out of curiosity, who's supposed to use device's private_data? >> I didn't find any user for ata_device's private_data in libata. > > All the ->private_data fields are to be used by low level drivers > (ahci, ata_piix, pata_via...). Given the twisted nature of ATA > devices, it's a bit surprising that no driver yet found a need for > ata_dev->private_data. For most SATA controllers, port to device is > one to one so maybe ap->private_data is enough. > >>> And this gets completely wrong. What if the device supports DA and >>> low level driver makes use of ->private_data? >> >> I didn't find any user of ata_device's private_data, so I used it for >> ZPODD. But if this is dangerous, I'll use a new field. > > As there currently is no other user, it won't break anything but yeah > please add a properly typed and named field. OK, and thanks for the suggestion. -Aaron > > Thanks. > -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c index fd9ecf7..3c61100 100644 --- a/drivers/ata/libata-acpi.c +++ b/drivers/ata/libata-acpi.c @@ -1059,6 +1059,8 @@ void ata_acpi_bind(struct ata_device *dev) void ata_acpi_unbind(struct ata_device *dev) { + if (zpodd_dev_enabled(dev)) + zpodd_deinit(dev); ata_acpi_remove_pm_notifier(dev); ata_acpi_unregister_power_resource(dev); } diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 3cc7096..a2293b6 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -2395,8 +2395,10 @@ 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) diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c index e69de29..fce6ea6 100644 --- a/drivers/ata/libata-zpodd.c +++ b/drivers/ata/libata-zpodd.c @@ -0,0 +1,124 @@ +#include <linux/libata.h> +#include <linux/cdrom.h> + +#include "libata.h" + +struct zpodd { + bool slot:1; + bool drawer:1; + + struct ata_device *dev; +}; + +static int run_atapi_cmd(struct ata_device *dev, const char *cdb, + unsigned short cdb_len, char *buf, unsigned int buf_len) +{ + struct ata_taskfile tf = {0}; + + tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE; + tf.command = ATA_CMD_PACKET; + + if (buf) { + tf.protocol = ATAPI_PROT_PIO; + tf.lbam = buf_len; + } else { + tf.protocol = ATAPI_PROT_NODATA; + } + + return ata_exec_internal(dev, &tf, cdb, + buf ? DMA_FROM_DEVICE : DMA_NONE, buf, buf_len, 0); +} + +/* + * Per the spec, only slot type and drawer type ODD can be supported + * + * Return 0 for slot type, 1 for drawer, -ENODEV for other types or on error. + */ +static int check_loading_mechanism(struct ata_device *dev) +{ + char buf[16]; + unsigned int ret; + struct rm_feature_desc *desc = (void *)(buf + 8); + + 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, + }; + + ret = run_atapi_cmd(dev, cdb, sizeof(cdb), buf, sizeof(buf)); + if (ret) + return -ENODEV; + + if (be16_to_cpu(desc->feature_code) != 3) + return -ENODEV; + + if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1) + return 0; /* slot */ + else if (desc->mech_type == 1 && desc->load == 0 && desc->eject == 1) + return 1; /* drawer */ + else + return -ENODEV; +} + +static bool device_can_poweroff(struct ata_device *ata_dev) +{ + acpi_handle handle; + acpi_status status; + struct acpi_device_power_state *states; + 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; + + /* + * If firmware has _PS3 or _PR3 for this device, + * it means this device can be runtime powered off + */ + states = acpi_dev->power.states; + if (states[ACPI_STATE_D3_HOT].flags.valid || + states[ACPI_STATE_D3_COLD].flags.explicit_set) + return true; + else + return false; +} + +void zpodd_init(struct ata_device *dev) +{ + int ret; + struct zpodd *zpodd; + + if (dev->private_data) + return; + + if (!device_can_poweroff(dev)) + return; + + if ((ret = check_loading_mechanism(dev)) == -ENODEV) + return; + + zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL); + if (!zpodd) + return; + + if (ret) + zpodd->drawer = true; + else + zpodd->slot = true; + + zpodd->dev = dev; + dev->private_data = zpodd; +} + +void zpodd_deinit(struct ata_device *dev) +{ + kfree(dev->private_data); + dev->private_data = NULL; +} diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h index 7148a58..55ad37e 100644 --- a/drivers/ata/libata.h +++ b/drivers/ata/libata.h @@ -230,4 +230,21 @@ 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_deinit(struct ata_device *dev); +static inline bool zpodd_dev_enabled(struct ata_device *dev) +{ + if (dev->flags & ATA_DFLAG_DA && dev->private_data) + return true; + else + return false; +} +#else /* CONFIG_SATA_ZPODD */ +static inline void zpodd_init(struct ata_device *dev) {} +static inline void zpodd_deinit(struct ata_device *dev) {} +static inline bool zpodd_dev_enabled(struct ata_device *dev) { return false; } +#endif /* CONFIG_SATA_ZPODD */ + #endif /* __LIBATA_H__ */ diff --git a/include/uapi/linux/cdrom.h b/include/uapi/linux/cdrom.h index 898b866..bd17ad5 100644 --- a/include/uapi/linux/cdrom.h +++ b/include/uapi/linux/cdrom.h @@ -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 */
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. Signed-off-by: Aaron Lu <aaron.lu@intel.com> --- drivers/ata/libata-acpi.c | 2 + drivers/ata/libata-core.c | 4 +- drivers/ata/libata-zpodd.c | 124 +++++++++++++++++++++++++++++++++++++++++++++ drivers/ata/libata.h | 17 +++++++ include/uapi/linux/cdrom.h | 34 +++++++++++++ 5 files changed, 180 insertions(+), 1 deletion(-)