Commit 79b42bab authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

libata: handle SEMB signature better 



WDC WD1600JS-62MHB5 successfully hits the window between ATA/ATAPI-7
and Serial ATA II standards and reports 3c/c3 signature which now is
assigned to SEMB.  Make ata_dev_classify() report ATA_DEV_SEMB on the
sig and let ata_dev_read_id() work around it by trying IDENTIFY once.

This fixes bko#11579.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Reported-by: default avatarDavid Haun <drhaun88@gmail.com>
Reported-by: default avatarLars Wirzenius <liw@liw.fi>
Reported-by: default avatarJuan Manuel <jmcarranza@gmail.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent 35c80d5f

drivers/ata/libata-core.c

+16 −2
Original line number Diff line number Diff line
@@ -1231,6 +1231,9 @@ unsigned int ata_dev_classify(const struct ata_taskfile *tf) 
	 *

	 * We follow the current spec and consider that 0x69/0x96

	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.

	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports

	 * SEMB signature.  This is worked around in

	 * ata_dev_read_id().

	 */

	if ((tf->lbam == 0) && (tf->lbah == 0)) {

		DPRINTK("found ATA device by sig\n");
@@ -1248,8 +1251,8 @@ unsigned int ata_dev_classify(const struct ata_taskfile *tf) 
	}



	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {

		printk(KERN_INFO "ata: SEMB device ignored\n");

		return ATA_DEV_SEMB_UNSUP; /* not yet */

		DPRINTK("found SEMB device by sig (could be ATA device)\n");

		return ATA_DEV_SEMB;

	}



	DPRINTK("unknown device\n");
@@ -2080,6 +2083,7 @@ int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class, 
	struct ata_taskfile tf;

	unsigned int err_mask = 0;

	const char *reason;

	bool is_semb = class == ATA_DEV_SEMB;

	int may_fallback = 1, tried_spinup = 0;

	int rc;
@@ -2090,6 +2094,8 @@ retry: 
	ata_tf_init(dev, &tf);



	switch (class) {

	case ATA_DEV_SEMB:

		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */

	case ATA_DEV_ATA:

		tf.command = ATA_CMD_ID_ATA;

		break;
@@ -2126,6 +2132,14 @@ retry: 
			return -ENOENT;

		}



		if (is_semb) {

			ata_dev_printk(dev, KERN_INFO, "IDENTIFY failed on "

				       "device w/ SEMB sig, disabled\n");

			/* SEMB is not supported yet */

			*p_class = ATA_DEV_SEMB_UNSUP;

			return 0;

		}



		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {

			/* Device or controller might have reported

			 * the wrong device class.  Give a shot at the

CRA Git | Maintained and supported by SUSTech CRA and CCSE