Linux-SCSI Archive on lore.kernel.org
 help / color / Atom feed
From: Can Guo <cang@codeaurora.org>
To: asutoshd@codeaurora.org, nguyenb@codeaurora.org,
	rnayak@codeaurora.org, linux-scsi@vger.kernel.org,
	kernel-team@android.com, saravanak@google.com,
	salyzyn@google.com, cang@codeaurora.org
Cc: Andy Gross <agross@kernel.org>,
	Alim Akhtar <alim.akhtar@samsung.com>,
	Avri Altman <avri.altman@wdc.com>,
	Pedro Sousa <pedrom.sousa@synopsys.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	linux-arm-msm@vger.kernel.org (open list:ARM/QUALCOMM SUPPORT),
	linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v5 2/7] scsi: ufs-qcom: Add reset control support for host controller
Date: Thu, 14 Nov 2019 22:09:25 -0800
Message-ID: <1573798172-20534-3-git-send-email-cang@codeaurora.org> (raw)
In-Reply-To: <1573798172-20534-1-git-send-email-cang@codeaurora.org>

Add reset control for host controller so that host controller can be reset
as required in its power up sequence.

Signed-off-by: Can Guo <cang@codeaurora.org>
---
 drivers/scsi/ufs/ufs-qcom.c | 53 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/ufs/ufs-qcom.h |  3 +++
 2 files changed, 56 insertions(+)

diff --git a/drivers/scsi/ufs/ufs-qcom.c b/drivers/scsi/ufs/ufs-qcom.c
index a5b7148..c69c29a1c 100644
--- a/drivers/scsi/ufs/ufs-qcom.c
+++ b/drivers/scsi/ufs/ufs-qcom.c
@@ -246,6 +246,44 @@ static void ufs_qcom_select_unipro_mode(struct ufs_qcom_host *host)
 	mb();
 }
 
+/**
+ * ufs_qcom_host_reset - reset host controller and PHY
+ */
+static int ufs_qcom_host_reset(struct ufs_hba *hba)
+{
+	int ret = 0;
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+
+	if (!host->core_reset) {
+		dev_warn(hba->dev, "%s: reset control not set\n", __func__);
+		goto out;
+	}
+
+	ret = reset_control_assert(host->core_reset);
+	if (ret) {
+		dev_err(hba->dev, "%s: core_reset assert failed, err = %d\n",
+				 __func__, ret);
+		goto out;
+	}
+
+	/*
+	 * The hardware requirement for delay between assert/deassert
+	 * is at least 3-4 sleep clock (32.7KHz) cycles, which comes to
+	 * ~125us (4/32768). To be on the safe side add 200us delay.
+	 */
+	usleep_range(200, 210);
+
+	ret = reset_control_deassert(host->core_reset);
+	if (ret)
+		dev_err(hba->dev, "%s: core_reset deassert failed, err = %d\n",
+				 __func__, ret);
+
+	usleep_range(1000, 1100);
+
+out:
+	return ret;
+}
+
 static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
@@ -254,6 +292,12 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 	bool is_rate_B = (UFS_QCOM_LIMIT_HS_RATE == PA_HS_MODE_B)
 							? true : false;
 
+	/* Reset UFS Host Controller and PHY */
+	ret = ufs_qcom_host_reset(hba);
+	if (ret)
+		dev_warn(hba->dev, "%s: host reset returned %d\n",
+				  __func__, ret);
+
 	if (is_rate_B)
 		phy_set_mode(phy, PHY_MODE_UFS_HS_B);
 
@@ -1101,6 +1145,15 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 	host->hba = hba;
 	ufshcd_set_variant(hba, host);
 
+	/* Setup the reset control of HCI */
+	host->core_reset = devm_reset_control_get(hba->dev, "rst");
+	if (IS_ERR(host->core_reset)) {
+		err = PTR_ERR(host->core_reset);
+		dev_warn(dev, "Failed to get reset control %d\n", err);
+		host->core_reset = NULL;
+		err = 0;
+	}
+
 	/* Fire up the reset controller. Failure here is non-fatal. */
 	host->rcdev.of_node = dev->of_node;
 	host->rcdev.ops = &ufs_qcom_reset_ops;
diff --git a/drivers/scsi/ufs/ufs-qcom.h b/drivers/scsi/ufs/ufs-qcom.h
index d401f17..2d95e7c 100644
--- a/drivers/scsi/ufs/ufs-qcom.h
+++ b/drivers/scsi/ufs/ufs-qcom.h
@@ -6,6 +6,7 @@
 #define UFS_QCOM_H_
 
 #include <linux/reset-controller.h>
+#include <linux/reset.h>
 
 #define MAX_UFS_QCOM_HOSTS	1
 #define MAX_U32                 (~(u32)0)
@@ -233,6 +234,8 @@ struct ufs_qcom_host {
 	u32 dbg_print_en;
 	struct ufs_qcom_testbus testbus;
 
+	/* Reset control of HCI */
+	struct reset_control *core_reset;
 	struct reset_controller_dev rcdev;
 
 	struct gpio_desc *device_reset;
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


  parent reply index

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-15  6:09 [PATCH v5 0/7] UFS driver general fixes bundle 3 Can Guo
2019-11-15  6:09 ` [PATCH v5 1/7] scsi: ufs: Add device reset in link recovery path Can Guo
2019-11-15  6:25   ` Stanley Chu
2019-11-15  6:09 ` Can Guo [this message]
2019-11-15 10:08   ` [PATCH v5 2/7] scsi: ufs-qcom: Add reset control support for host controller Avri Altman
2019-12-16 19:04   ` Vinod Koul
2019-12-16 19:12     ` Jeffrey Hugo
2019-12-17  0:37       ` cang
2019-12-17  4:13         ` Vinod Koul
2019-12-17  7:10           ` cang
2019-12-17  9:24             ` Vinod Koul
2019-12-17 10:09               ` cang
2019-12-17 15:08                 ` Vinod Koul
2019-12-17 16:00                   ` Jeffrey Hugo
2019-12-17 18:44                     ` cang
2019-12-18  4:12                       ` Vinod Koul
2019-12-19  7:12                         ` cang
2019-12-19 14:21                           ` Vinod Koul
2019-12-19 14:25                             ` Jeffrey Hugo
2019-12-19 14:52                               ` Vinod Koul
2019-12-20  0:30                                 ` cang
2019-11-15  6:09 ` [PATCH v5 3/7] scsi: ufs: Fix up auto hibern8 enablement Can Guo
2019-11-15  6:35   ` Stanley Chu
2019-11-15  7:03     ` Can Guo
2019-11-15  7:18       ` Stanley Chu
2019-11-15 12:27         ` Can Guo
2019-11-15 13:46           ` Stanley Chu
2019-11-15  6:09 ` [PATCH v5 4/7] scsi: ufs: Fix register dump caused sleep in atomic context Can Guo
2019-11-15  6:09 ` [PATCH v5 5/7] scsi: ufs: Fix irq return code Can Guo
2019-11-15  6:09 ` [PATCH v5 6/7] scsi: ufs: Abort gating if clock on request is pending Can Guo
2019-11-15  6:09 ` [PATCH v5 7/7] scsi: ufs: Fix error handing during hibern8 enter Can Guo
2019-11-15 10:12   ` Avri Altman
2019-11-17 16:36   ` [EXT] " Bean Huo (beanhuo)
2019-11-19  4:28 ` [PATCH v5 0/7] UFS driver general fixes bundle 3 Martin K. Petersen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1573798172-20534-3-git-send-email-cang@codeaurora.org \
    --to=cang@codeaurora.org \
    --cc=agross@kernel.org \
    --cc=alim.akhtar@samsung.com \
    --cc=asutoshd@codeaurora.org \
    --cc=avri.altman@wdc.com \
    --cc=jejb@linux.ibm.com \
    --cc=kernel-team@android.com \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=nguyenb@codeaurora.org \
    --cc=pedrom.sousa@synopsys.com \
    --cc=rnayak@codeaurora.org \
    --cc=salyzyn@google.com \
    --cc=saravanak@google.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-SCSI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-scsi/0 linux-scsi/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-scsi linux-scsi/ https://lore.kernel.org/linux-scsi \
		linux-scsi@vger.kernel.org
	public-inbox-index linux-scsi

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-scsi


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git