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path: root/drivers/phy/phy-lpc18xx-usb-otg.c
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Diffstat (limited to 'drivers/phy/phy-lpc18xx-usb-otg.c')
-rw-r--r--drivers/phy/phy-lpc18xx-usb-otg.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/drivers/phy/phy-lpc18xx-usb-otg.c b/drivers/phy/phy-lpc18xx-usb-otg.c
new file mode 100644
index 000000000000..3b7a71eb5b7e
--- /dev/null
+++ b/drivers/phy/phy-lpc18xx-usb-otg.c
@@ -0,0 +1,143 @@
+/*
+ * PHY driver for NXP LPC18xx/43xx internal USB OTG PHY
+ *
+ * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* USB OTG PHY register offset and bit in CREG */
+#define LPC18XX_CREG_CREG0 0x004
+#define LPC18XX_CREG_CREG0_USB0PHY BIT(5)
+
+struct lpc18xx_usb_otg_phy {
+ struct phy *phy;
+ struct clk *clk;
+ struct regmap *reg;
+};
+
+static int lpc18xx_usb_otg_phy_init(struct phy *phy)
+{
+ struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
+ int ret;
+
+ /* The PHY must be clocked at 480 MHz */
+ ret = clk_set_rate(lpc->clk, 480000000);
+ if (ret)
+ return ret;
+
+ return clk_prepare(lpc->clk);
+}
+
+static int lpc18xx_usb_otg_phy_exit(struct phy *phy)
+{
+ struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
+
+ clk_unprepare(lpc->clk);
+
+ return 0;
+}
+
+static int lpc18xx_usb_otg_phy_power_on(struct phy *phy)
+{
+ struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
+ int ret;
+
+ ret = clk_enable(lpc->clk);
+ if (ret)
+ return ret;
+
+ /* The bit in CREG is cleared to enable the PHY */
+ return regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0,
+ LPC18XX_CREG_CREG0_USB0PHY, 0);
+}
+
+static int lpc18xx_usb_otg_phy_power_off(struct phy *phy)
+{
+ struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
+ int ret;
+
+ ret = regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0,
+ LPC18XX_CREG_CREG0_USB0PHY,
+ LPC18XX_CREG_CREG0_USB0PHY);
+ if (ret)
+ return ret;
+
+ clk_disable(lpc->clk);
+
+ return 0;
+}
+
+static const struct phy_ops lpc18xx_usb_otg_phy_ops = {
+ .init = lpc18xx_usb_otg_phy_init,
+ .exit = lpc18xx_usb_otg_phy_exit,
+ .power_on = lpc18xx_usb_otg_phy_power_on,
+ .power_off = lpc18xx_usb_otg_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int lpc18xx_usb_otg_phy_probe(struct platform_device *pdev)
+{
+ struct phy_provider *phy_provider;
+ struct lpc18xx_usb_otg_phy *lpc;
+
+ lpc = devm_kzalloc(&pdev->dev, sizeof(*lpc), GFP_KERNEL);
+ if (!lpc)
+ return -ENOMEM;
+
+ lpc->reg = syscon_node_to_regmap(pdev->dev.of_node->parent);
+ if (IS_ERR(lpc->reg)) {
+ dev_err(&pdev->dev, "failed to get syscon\n");
+ return PTR_ERR(lpc->reg);
+ }
+
+ lpc->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(lpc->clk)) {
+ dev_err(&pdev->dev, "failed to get clock\n");
+ return PTR_ERR(lpc->clk);
+ }
+
+ lpc->phy = devm_phy_create(&pdev->dev, NULL, &lpc18xx_usb_otg_phy_ops);
+ if (IS_ERR(lpc->phy)) {
+ dev_err(&pdev->dev, "failed to create PHY\n");
+ return PTR_ERR(lpc->phy);
+ }
+
+ phy_set_drvdata(lpc->phy, lpc);
+
+ phy_provider = devm_of_phy_provider_register(&pdev->dev,
+ of_phy_simple_xlate);
+
+ return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id lpc18xx_usb_otg_phy_match[] = {
+ { .compatible = "nxp,lpc1850-usb-otg-phy" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, lpc18xx_usb_otg_phy_match);
+
+static struct platform_driver lpc18xx_usb_otg_phy_driver = {
+ .probe = lpc18xx_usb_otg_phy_probe,
+ .driver = {
+ .name = "lpc18xx-usb-otg-phy",
+ .of_match_table = lpc18xx_usb_otg_phy_match,
+ },
+};
+module_platform_driver(lpc18xx_usb_otg_phy_driver);
+
+MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
+MODULE_DESCRIPTION("NXP LPC18xx/43xx USB OTG PHY driver");
+MODULE_LICENSE("GPL v2");
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