diff options
Diffstat (limited to 'drivers/phy/phy-lpc18xx-usb-otg.c')
-rw-r--r-- | drivers/phy/phy-lpc18xx-usb-otg.c | 149 |
1 files changed, 149 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 000000000..7de280a45 --- /dev/null +++ b/drivers/phy/phy-lpc18xx-usb-otg.c @@ -0,0 +1,149 @@ +/* + * 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 */ + ret = regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0, + LPC18XX_CREG_CREG0_USB0PHY, 0); + if (ret) { + clk_disable(lpc->clk); + return ret; + } + + return 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"); |