From b334456ec2021b1addc19806990115e69ec4ac32 Mon Sep 17 00:00:00 2001 From: Subhash Jadavani Date: Thu, 3 May 2018 16:37:17 +0530 Subject: [PATCH] scsi: ufs: ufshcd: fix possible unclocked register access Vendor specific setup_clocks ops may depend on clocks managed by ufshcd driver so if the vendor specific setup_clocks callback is called when the required clocks are turned off, it results into unclocked register access. This change make sure that required clocks are enabled before vendor specific setup_clocks callback is called. Signed-off-by: Subhash Jadavani Signed-off-by: Venkat Gopalakrishnan Signed-off-by: Can Guo Signed-off-by: Asutosh Das Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufshcd.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 4dc4880..7959193 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6912,9 +6912,16 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on, if (list_empty(head)) goto out; - ret = ufshcd_vops_setup_clocks(hba, on, PRE_CHANGE); - if (ret) - return ret; + /* + * vendor specific setup_clocks ops may depend on clocks managed by + * this standard driver hence call the vendor specific setup_clocks + * before disabling the clocks managed here. + */ + if (!on) { + ret = ufshcd_vops_setup_clocks(hba, on, PRE_CHANGE); + if (ret) + return ret; + } list_for_each_entry(clki, head, list) { if (!IS_ERR_OR_NULL(clki->clk)) { @@ -6938,9 +6945,16 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on, } } - ret = ufshcd_vops_setup_clocks(hba, on, POST_CHANGE); - if (ret) - return ret; + /* + * vendor specific setup_clocks ops may depend on clocks managed by + * this standard driver hence call the vendor specific setup_clocks + * after enabling the clocks managed here. + */ + if (on) { + ret = ufshcd_vops_setup_clocks(hba, on, POST_CHANGE); + if (ret) + return ret; + } out: if (ret) { -- 2.7.4