Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756441Ab3EJOce (ORCPT ); Fri, 10 May 2013 10:32:34 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:57218 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755574Ab3EJOVg (ORCPT ); Fri, 10 May 2013 10:21:36 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Greg Kroah-Hartman" , "Tormod Volden" Date: Fri, 10 May 2013 14:39:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [049/118] usb-storage: CY7C68300A chips do not support Cypress ATACB In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:d51a:8785:aa0a:cebe X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3062 Lines: 80 3.2.45-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Tormod Volden commit 671b4b2ba9266cbcfe7210a704e9ea487dcaa988 upstream. Many cards based on CY7C68300A/B/C use the USB ID 04b4:6830 but only the B and C variants (EZ-USB AT2LP) support the ATA Command Block functionality, according to the data sheets. The A variant (EZ-USB AT2) locks up if ATACB is attempted, until a typical 30 seconds timeout runs out and a USB reset is performed. https://bugs.launchpad.net/bugs/428469 It seems that one way to spot a CY7C68300A (at least where the card manufacturer left Cypress' EEPROM default vaules, against Cypress' recommendations) is to look at the USB string descriptor indices. A http://media.digikey.com/pdf/Data%20Sheets/Cypress%20PDFs/CY7C68300A.pdf B http://www.farnell.com/datasheets/43456.pdf C http://www.cypress.com/?rID=14189 Note that a CY7C68300B/C chip appears as CY7C68300A if it is running in Backward Compatibility Mode, and if ATACB would be supported in this case there is anyway no way to tell which chip it really is. For 5 years my external USB drive has been locking up for half a minute when plugged in and ata_id is run by udev, or anytime hdparm or similar is run on it. Finally looking at the /correct/ datasheet I think I found the reason. I am aware the quirk in this patch is a bit hacky, but the hardware manufacturers haven't made it easy for us. Signed-off-by: Tormod Volden Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/storage/cypress_atacb.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) --- a/drivers/usb/storage/cypress_atacb.c +++ b/drivers/usb/storage/cypress_atacb.c @@ -248,14 +248,26 @@ static int cypress_probe(struct usb_inte { struct us_data *us; int result; + struct usb_device *device; result = usb_stor_probe1(&us, intf, id, (id - cypress_usb_ids) + cypress_unusual_dev_list); if (result) return result; - us->protocol_name = "Transparent SCSI with Cypress ATACB"; - us->proto_handler = cypress_atacb_passthrough; + /* Among CY7C68300 chips, the A revision does not support Cypress ATACB + * Filter out this revision from EEPROM default descriptor values + */ + device = interface_to_usbdev(intf); + if (device->descriptor.iManufacturer != 0x38 || + device->descriptor.iProduct != 0x4e || + device->descriptor.iSerialNumber != 0x64) { + us->protocol_name = "Transparent SCSI with Cypress ATACB"; + us->proto_handler = cypress_atacb_passthrough; + } else { + us->protocol_name = "Transparent SCSI"; + us->proto_handler = usb_stor_transparent_scsi_command; + } result = usb_stor_probe2(us); return result; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/