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@xxxxxxxxxxxxxx> --- .../devicetree/bindings/ufs/ufshcd-pltfrm.txt | 15 +++- drivers/scsi/ufs/ufshcd-pltfrm.c | 71 +++++++++++++++++ drivers/scsi/ufs/ufshcd.c | 89 +++++++++++++++++++++- drivers/scsi/ufs/ufshcd.h | 18 +++++ 4 files changed, 190 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt index 65e3117..b0f791a 100644 --- a/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt +++ b/Documentation/devicetree/bindings/ufs/ufshcd-pltfrm.txt @@ -21,8 +21,17 @@ Optional properties: - vccq-max-microamp : specifies max. load that can be drawn from vccq supply - vccq2-max-microamp : specifies max. load that can be drawn from vccq2 supply +- clocks : List of phandle and clock specifier pairs +- clock-names : List of clock input name strings sorted in the same + order as the clocks property. +- max-clock-frequency-hz : List of maximum operating frequency stored in the same + order as the clocks property. If this property is not + defined or a value in the array is "0" then it is assumed + that the frequency is set by the parent clock or a + fixed rate clock source. + Note: If above properties are not defined it can be assumed that the supply -regulators are always on. +regulators or clocks are always on. Example: ufshc@0xfc598000 { @@ -37,4 +46,8 @@ Example: vcc-max-microamp = 500000; vccq-max-microamp = 200000; vccq2-max-microamp = 200000; + + clocks = <&core 0>, <&ref 0>, <&iface 0>; + clock-names = "core_clk", "ref_clk", "iface_clk"; + max-clock-frequency-hz = <100000000 19200000 0>; }; diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c index cbdf5f3..15c8086 100644 --- a/drivers/scsi/ufs/ufshcd-pltfrm.c +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c @@ -52,6 +52,71 @@ static struct ufs_hba_variant_ops *get_variant_ops(struct device *dev) return NULL; } +static int ufshcd_parse_clock_info(struct ufs_hba *hba) +{ + int ret = 0; + int cnt; + int i; + struct device *dev = hba->dev; + struct device_node *np = dev->of_node; + char *name; + u32 *clkfreq = NULL; + struct ufs_clk_info *clki; + + if (!np) + goto out; + + INIT_LIST_HEAD(&hba->clk_list_head); + + cnt = of_property_count_strings(np, "clock-names"); + if (!cnt || (cnt == -EINVAL)) { + dev_info(dev, "%s: Unable to find clocks, assuming enabled\n", + __func__); + } else if (cnt < 0) { + dev_err(dev, "%s: count clock strings failed, err %d\n", + __func__, cnt); + ret = cnt; + } + + if (cnt <= 0) + goto out; + + clkfreq = kzalloc(cnt * sizeof(*clkfreq), GFP_KERNEL); + if (!clkfreq) { + ret = -ENOMEM; + dev_err(dev, "%s: memory alloc failed\n", __func__); + goto out; + } + + ret = of_property_read_u32_array(np, + "max-clock-frequency-hz", clkfreq, cnt); + if (ret && (ret != -EINVAL)) { + dev_err(dev, "%s: invalid max-clock-frequency-hz property, %d\n", + __func__, ret); + goto out; + } + + for (i = 0; i < cnt; i++) { + ret = of_property_read_string_index(np, + "clock-names", i, (const char **)&name); + if (ret) + goto out; + + clki = devm_kzalloc(dev, sizeof(*clki), GFP_KERNEL); + if (!clki) { + ret = -ENOMEM; + goto out; + } + + clki->max_freq = clkfreq[i]; + clki->name = kstrdup(name, GFP_KERNEL); + list_add_tail(&clki->list, &hba->clk_list_head); + } +out: + kfree(clkfreq); + return ret; +} + #define MAX_PROP_SIZE 32 static int ufshcd_populate_vreg(struct device *dev, const char *name, struct ufs_vreg **out_vreg) @@ -265,6 +330,12 @@ static int ufshcd_pltfrm_probe(struct platform_device *pdev) hba->vops = get_variant_ops(&pdev->dev); + err = ufshcd_parse_clock_info(hba); + if (err) { + dev_err(&pdev->dev, "%s: clock parse failed %d\n", + __func__, err); + goto out; + } err = ufshcd_parse_regulator_info(hba); if (err) { dev_err(&pdev->dev, "%s: regulator init failed %d\n", diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index e520b15..61c6e54 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -2983,6 +2983,80 @@ 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; @@ -3042,14 +3116,22 @@ 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; @@ -3058,6 +3140,8 @@ 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; } @@ -3066,6 +3150,7 @@ static void ufshcd_hba_exit(struct ufs_hba *hba) { ufshcd_variant_hba_exit(hba); ufshcd_setup_vreg(hba, false); + ufshcd_setup_clocks(hba, false); } /** diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index f66e58c..1e91687 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -155,6 +155,22 @@ struct ufs_dev_cmd { struct ufs_query query; }; +/** + * struct ufs_clk_info - UFS clock related info + * @list: list headed by hba->clk_list_head + * @clk: clock node + * @name: clock name + * @max_freq: maximum frequency supported by the clock + * @enabled: variable to check against multiple enable/disable + */ +struct ufs_clk_info { + struct list_head list; + struct clk *clk; + const char *name; + u32 max_freq; + bool enabled; +}; + #define PRE_CHANGE 0 #define POST_CHANGE 1 /** @@ -220,6 +236,7 @@ struct ufs_hba_variant_ops { * @dev_cmd: ufs device management command information * @auto_bkops_enabled: to track whether bkops is enabled in device * @vreg_info: UFS device voltage regulator information + * @clk_list_head: UFS host controller clocks list node head */ struct ufs_hba { void __iomem *mmio_base; @@ -279,6 +296,7 @@ struct ufs_hba { bool auto_bkops_enabled; struct ufs_vreg_info vreg_info; + struct list_head clk_list_head; }; #define ufshcd_writel(hba, val, reg) \ -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html