diff options
author | Sujit Reddy Thumma <sthumma@codeaurora.org> | 2014-09-25 16:32:23 +0400 |
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committer | Christoph Hellwig <hch@lst.de> | 2014-10-01 15:11:19 +0400 |
commit | c6e79dacd86fd7ddd452fa52b3f4ca996db31e49 (patch) | |
tree | a1482fd92a23e1c34eaaaaf3a70c1339f1b81eb6 /drivers/scsi/ufs/ufshcd.c | |
parent | aa497613093412ee26ef4bfa4ffec8391553dfca (diff) | |
download | linux-c6e79dacd86fd7ddd452fa52b3f4ca996db31e49.tar.xz |
ufs: Add clock initialization support
Add generic clock initialization support for UFSHCD platform
driver. The clock info is read from device tree using standard
clock bindings. A generic max-clock-frequency-hz property is
defined to save information on maximum operating clock frequency
the h/w supports.
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>
Signed-off-by: Dolev Raviv <draviv@codeaurora.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Diffstat (limited to 'drivers/scsi/ufs/ufshcd.c')
-rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 89 |
1 files changed, 87 insertions, 2 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index ef8519e70e97..b03370292070 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -3350,6 +3350,80 @@ out: return ret; } +static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on) +{ + int ret = 0; + struct ufs_clk_info *clki; + struct list_head *head = &hba->clk_list_head; + + if (!head || list_empty(head)) + goto out; + + list_for_each_entry(clki, head, list) { + if (!IS_ERR_OR_NULL(clki->clk)) { + if (on && !clki->enabled) { + ret = clk_prepare_enable(clki->clk); + if (ret) { + dev_err(hba->dev, "%s: %s prepare enable failed, %d\n", + __func__, clki->name, ret); + goto out; + } + } else if (!on && clki->enabled) { + clk_disable_unprepare(clki->clk); + } + clki->enabled = on; + dev_dbg(hba->dev, "%s: clk: %s %sabled\n", __func__, + clki->name, on ? "en" : "dis"); + } + } +out: + if (ret) { + list_for_each_entry(clki, head, list) { + if (!IS_ERR_OR_NULL(clki->clk) && clki->enabled) + clk_disable_unprepare(clki->clk); + } + } + return ret; +} + +static int ufshcd_init_clocks(struct ufs_hba *hba) +{ + int ret = 0; + struct ufs_clk_info *clki; + struct device *dev = hba->dev; + struct list_head *head = &hba->clk_list_head; + + if (!head || list_empty(head)) + goto out; + + list_for_each_entry(clki, head, list) { + if (!clki->name) + continue; + + clki->clk = devm_clk_get(dev, clki->name); + if (IS_ERR(clki->clk)) { + ret = PTR_ERR(clki->clk); + dev_err(dev, "%s: %s clk get failed, %d\n", + __func__, clki->name, ret); + goto out; + } + + if (clki->max_freq) { + ret = clk_set_rate(clki->clk, clki->max_freq); + if (ret) { + dev_err(hba->dev, "%s: %s clk set rate(%dHz) failed, %d\n", + __func__, clki->name, + clki->max_freq, ret); + goto out; + } + } + dev_dbg(dev, "%s: clk: %s, rate: %lu\n", __func__, + clki->name, clk_get_rate(clki->clk)); + } +out: + return ret; +} + static int ufshcd_variant_hba_init(struct ufs_hba *hba) { int err = 0; @@ -3409,14 +3483,22 @@ static int ufshcd_hba_init(struct ufs_hba *hba) { int err; - err = ufshcd_init_vreg(hba); + err = ufshcd_init_clocks(hba); if (err) goto out; - err = ufshcd_setup_vreg(hba, true); + err = ufshcd_setup_clocks(hba, true); if (err) goto out; + err = ufshcd_init_vreg(hba); + if (err) + goto out_disable_clks; + + err = ufshcd_setup_vreg(hba, true); + if (err) + goto out_disable_clks; + err = ufshcd_variant_hba_init(hba); if (err) goto out_disable_vreg; @@ -3425,6 +3507,8 @@ static int ufshcd_hba_init(struct ufs_hba *hba) out_disable_vreg: ufshcd_setup_vreg(hba, false); +out_disable_clks: + ufshcd_setup_clocks(hba, false); out: return err; } @@ -3433,6 +3517,7 @@ static void ufshcd_hba_exit(struct ufs_hba *hba) { ufshcd_variant_hba_exit(hba); ufshcd_setup_vreg(hba, false); + ufshcd_setup_clocks(hba, false); } /** |