Revert "scsi: ufs: disable vccq if it's not needed by UFS device"

This reverts commit 60f0187031c05e04cbadffb62f557d0ff3564490.

There was one conflict in drivers/scsi/ufs/ufshcd.c

<<<<<<< HEAD
	/* Init check for device descriptor sizes */
	ufshcd_init_desc_sizes(hba);

	ret = ufs_get_device_desc(hba, &card);
	if (ret) {
		dev_err(hba->dev, "%s: Failed getting device info. err = %d\n",
			__func__, ret);
		goto out;
	}

	ufs_fixup_device_setup(hba, &card);
	ufshcd_tune_unipro_params(hba);

	ret = ufshcd_set_vccq_rail_unused(hba,
		(hba->dev_quirks & UFS_DEVICE_NO_VCCQ) ? true : false);
	if (ret)
		goto out;

=======
	ufs_advertise_fixup_device(hba);
>>>>>>> parent of 60f0187031c0... scsi: ufs: disable vccq if it's not needed by UFS device

Resolution: keep HEAD, and delete the ufshcd_set_vccq_rail_unused() call
and corresponding error-handling code.

Clean up loose ends in a follow-up patch.

60f0187031c0 introduced a small power optimization: ignore the vccq load
specified in the UFSHC DT node when said host controller is connected to
specific Flash chips (currently, Samsung and Hynix).

Unfortunately, this optimization breaks UFS on systems where vccq powers
not only the Flash chip, but the host controller as well, such as APQ8098
MEDIABOX or MTP8998:

[    3.929877] ufshcd-qcom 1da4000.ufshc: ufshcd_query_attr: opcode 0x04 for idn 13 failed, index 0, err = -11
[    5.433815] ufshcd-qcom 1da4000.ufshc: ufshcd_query_attr: opcode 0x04 for idn 13 failed, index 0, err = -11
[    6.937771] ufshcd-qcom 1da4000.ufshc: ufshcd_query_attr: opcode 0x04 for idn 13 failed, index 0, err = -11
[    6.937866] ufshcd-qcom 1da4000.ufshc: ufshcd_query_attr_retry: query attribute, idn 13, failed with error -11 after 3 retires
[    6.946412] ufshcd-qcom 1da4000.ufshc: ufshcd_disable_auto_bkops: failed to enable exception event -11
[    6.957972] ufshcd-qcom 1da4000.ufshc: dme-peer-get: attr-id 0x1587 failed 3 retries
[    6.967181] ufshcd-qcom 1da4000.ufshc: dme-peer-get: attr-id 0x1586 failed 3 retries
[    6.975025] ufshcd-qcom 1da4000.ufshc: ufshcd_get_max_pwr_mode: invalid max pwm tx gear read = 0
[    6.982755] ufshcd-qcom 1da4000.ufshc: ufshcd_probe_hba: Failed getting max supported power mode
[    8.505770] ufshcd-qcom 1da4000.ufshc: ufshcd_query_flag: Sending flag query for idn 3 failed, err = -11
[   10.009807] ufshcd-qcom 1da4000.ufshc: ufshcd_query_flag: Sending flag query for idn 3 failed, err = -11
[   11.513766] ufshcd-qcom 1da4000.ufshc: ufshcd_query_flag: Sending flag query for idn 3 failed, err = -11
[   11.513861] ufshcd-qcom 1da4000.ufshc: ufshcd_query_flag_retry: query attribute, opcode 5, idn 3, failed with error -11 after 3 retires
[   13.049807] ufshcd-qcom 1da4000.ufshc: __ufshcd_query_descriptor: opcode 0x01 for idn 8 failed, index 0, err = -11
[   14.553768] ufshcd-qcom 1da4000.ufshc: __ufshcd_query_descriptor: opcode 0x01 for idn 8 failed, index 0, err = -11
[   16.057767] ufshcd-qcom 1da4000.ufshc: __ufshcd_query_descriptor: opcode 0x01 for idn 8 failed, index 0, err = -11
[   16.057872] ufshcd-qcom 1da4000.ufshc: ufshcd_read_desc_param: Failed reading descriptor. desc_id 8, desc_index 0, param_offset 0, ret -11
[   16.067109] ufshcd-qcom 1da4000.ufshc: ufshcd_init_icc_levels: Failed reading power descriptor.len = 98 ret = -11
[   37.073787] ufshcd-qcom 1da4000.ufshc: link startup failed 1

In my opinion, the rationale for the original patch is questionable.  If
neither the UFSHC, nor the Flash chip, require any load from vccq, then
that power rail should simply not be specified at all in the DT.

Working around that fact in the driver is detrimental, as evidenced by the
failure to initialize the host controller on MSM8998.

Acked-by: Avri Altman <avri.altman@wdc.com>
Acked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
index dd65fea07687..7da7318eb6a6 100644
--- a/drivers/scsi/ufs/ufs.h
+++ b/drivers/scsi/ufs/ufs.h
@@ -514,7 +514,6 @@ struct ufs_vreg {
 	struct regulator *reg;
 	const char *name;
 	bool enabled;
-	bool unused;
 	int min_uV;
 	int max_uV;
 	int min_uA;