On 1/21/23 23:53, Ondrej Zary wrote:
The pata_parport is a libata-based replacement of the old PARIDE subsystem - driver for parallel port IDE devices. It uses the original paride low-level protocol drivers but does not need the high-level drivers (pd, pcd, pf, pt, pg). The IDE devices behind parallel port adapters are handled by the ATA layer. This will allow paride and its high-level drivers to be removed. Unfortunately, libata drivers cannot sleep so pata_parport claims parport before activating the ata host and keeps it claimed (and protocol connected) until the ata host is removed. This means that no devices can be chained (neither other pata_parport devices nor a printer). paride and pata_parport are mutually exclusive because the compiled protocol drivers are incompatible. Tested with: - Imation SuperDisk LS-120 and HP C4381A (EPAT) - Freecom Parallel CD (FRPW) - Toshiba Mobile CD-RW 2793008 w/Freecom Parallel Cable rev.903 (FRIQ) - Backpack CD-RW 222011 and CD-RW 19350 (BPCK6) The following bugs in low-level protocol drivers were found and will be fixed later: Note: EPP-32 mode is buggy in EPAT - and also in all other protocol drivers - they don't handle non-multiple-of-4 block transfers correctly. This causes problems with LS-120 drive. There is also another bug in EPAT: EPP modes don't work unless a 4-bit or 8-bit mode is used first (probably some initialization missing?). Once the device is initialized, EPP works until power cycle. So after device power on, you have to: echo "parport0 epat 0" >/sys/bus/pata_parport/new_device echo pata_parport.0 >/sys/bus/pata_parport/delete_device echo "parport0 epat 4" >/sys/bus/pata_parport/new_device (autoprobe will initialize correctly as it tries the slowest modes first but you'll get the broken EPP-32 mode) Note: EPP modes are buggy in FRPW, only modes 0 and 1 work. Signed-off-by: Ondrej Zary <linux@xxxxxxx> --- Changes in v2: - keep device connected, remove disconnect timer Documentation/admin-guide/blockdev/paride.rst | 52 ++ drivers/Makefile | 2 +- drivers/ata/Kconfig | 14 + drivers/ata/Makefile | 2 + drivers/ata/pata_parport.c | 783 ++++++++++++++++++ drivers/block/paride/Kconfig | 32 +- drivers/block/paride/paride.h | 13 + include/linux/pata_parport.h | 106 +++ 8 files changed, 987 insertions(+), 17 deletions(-) create mode 100644 drivers/ata/pata_parport.c create mode 100644 include/linux/pata_parport.h
Reviewed-by: Hannes Reinecke <hare@xxxxxxx> Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@xxxxxxx +49 911 74053 688 SUSE Software Solutions Germany GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), GF: Felix Imendörffer
