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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/clk/renesas/rcar-usb2-clock-sel.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clk/renesas/rcar-usb2-clock-sel.c')
-rw-r--r--drivers/clk/renesas/rcar-usb2-clock-sel.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/clk/renesas/rcar-usb2-clock-sel.c b/drivers/clk/renesas/rcar-usb2-clock-sel.c
new file mode 100644
index 000000000..6cd030a58
--- /dev/null
+++ b/drivers/clk/renesas/rcar-usb2-clock-sel.c
@@ -0,0 +1,188 @@
+/*
+ * Renesas R-Car USB2.0 clock selector
+ *
+ * Copyright (C) 2017 Renesas Electronics Corp.
+ *
+ * Based on renesas-cpg-mssr.c
+ *
+ * Copyright (C) 2015 Glider bvba
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+
+#define USB20_CLKSET0 0x00
+#define CLKSET0_INTCLK_EN BIT(11)
+#define CLKSET0_PRIVATE BIT(0)
+#define CLKSET0_EXTAL_ONLY (CLKSET0_INTCLK_EN | CLKSET0_PRIVATE)
+
+struct usb2_clock_sel_priv {
+ void __iomem *base;
+ struct clk_hw hw;
+ bool extal;
+ bool xtal;
+};
+#define to_priv(_hw) container_of(_hw, struct usb2_clock_sel_priv, hw)
+
+static void usb2_clock_sel_enable_extal_only(struct usb2_clock_sel_priv *priv)
+{
+ u16 val = readw(priv->base + USB20_CLKSET0);
+
+ pr_debug("%s: enter %d %d %x\n", __func__,
+ priv->extal, priv->xtal, val);
+
+ if (priv->extal && !priv->xtal && val != CLKSET0_EXTAL_ONLY)
+ writew(CLKSET0_EXTAL_ONLY, priv->base + USB20_CLKSET0);
+}
+
+static void usb2_clock_sel_disable_extal_only(struct usb2_clock_sel_priv *priv)
+{
+ if (priv->extal && !priv->xtal)
+ writew(CLKSET0_PRIVATE, priv->base + USB20_CLKSET0);
+}
+
+static int usb2_clock_sel_enable(struct clk_hw *hw)
+{
+ usb2_clock_sel_enable_extal_only(to_priv(hw));
+
+ return 0;
+}
+
+static void usb2_clock_sel_disable(struct clk_hw *hw)
+{
+ usb2_clock_sel_disable_extal_only(to_priv(hw));
+}
+
+/*
+ * This module seems a mux, but this driver assumes a gate because
+ * ehci/ohci platform drivers don't support clk_set_parent() for now.
+ * If this driver acts as a gate, ehci/ohci-platform drivers don't need
+ * any modification.
+ */
+static const struct clk_ops usb2_clock_sel_clock_ops = {
+ .enable = usb2_clock_sel_enable,
+ .disable = usb2_clock_sel_disable,
+};
+
+static const struct of_device_id rcar_usb2_clock_sel_match[] = {
+ { .compatible = "renesas,rcar-gen3-usb2-clock-sel" },
+ { }
+};
+
+static int rcar_usb2_clock_sel_suspend(struct device *dev)
+{
+ struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
+
+ usb2_clock_sel_disable_extal_only(priv);
+ pm_runtime_put(dev);
+
+ return 0;
+}
+
+static int rcar_usb2_clock_sel_resume(struct device *dev)
+{
+ struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
+
+ pm_runtime_get_sync(dev);
+ usb2_clock_sel_enable_extal_only(priv);
+
+ return 0;
+}
+
+static int rcar_usb2_clock_sel_remove(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct usb2_clock_sel_priv *priv = platform_get_drvdata(pdev);
+
+ of_clk_del_provider(dev->of_node);
+ clk_hw_unregister(&priv->hw);
+ pm_runtime_put(dev);
+ pm_runtime_disable(dev);
+
+ return 0;
+}
+
+static int rcar_usb2_clock_sel_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct usb2_clock_sel_priv *priv;
+ struct resource *res;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ pm_runtime_enable(dev);
+ pm_runtime_get_sync(dev);
+
+ clk = devm_clk_get(dev, "usb_extal");
+ if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
+ priv->extal = !!clk_get_rate(clk);
+ clk_disable_unprepare(clk);
+ }
+ clk = devm_clk_get(dev, "usb_xtal");
+ if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
+ priv->xtal = !!clk_get_rate(clk);
+ clk_disable_unprepare(clk);
+ }
+
+ if (!priv->extal && !priv->xtal) {
+ dev_err(dev, "This driver needs usb_extal or usb_xtal\n");
+ return -ENOENT;
+ }
+
+ platform_set_drvdata(pdev, priv);
+ dev_set_drvdata(dev, priv);
+
+ init.name = "rcar_usb2_clock_sel";
+ init.ops = &usb2_clock_sel_clock_ops;
+ init.flags = 0;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+ priv->hw.init = &init;
+
+ clk = clk_register(NULL, &priv->hw);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
+}
+
+static const struct dev_pm_ops rcar_usb2_clock_sel_pm_ops = {
+ .suspend = rcar_usb2_clock_sel_suspend,
+ .resume = rcar_usb2_clock_sel_resume,
+};
+
+static struct platform_driver rcar_usb2_clock_sel_driver = {
+ .driver = {
+ .name = "rcar-usb2-clock-sel",
+ .of_match_table = rcar_usb2_clock_sel_match,
+ .pm = &rcar_usb2_clock_sel_pm_ops,
+ },
+ .probe = rcar_usb2_clock_sel_probe,
+ .remove = rcar_usb2_clock_sel_remove,
+};
+builtin_platform_driver(rcar_usb2_clock_sel_driver);
+
+MODULE_DESCRIPTION("Renesas R-Car USB2 clock selector Driver");
+MODULE_LICENSE("GPL v2");