1/**
  2 * Copyright (C) 2016 Linaro Ltd
  3 *
  4 * This program is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License version 2 as
  6 * published by the Free Software Foundation.
  7 */
  8#include <linux/module.h>
  9#include <linux/ulpi/driver.h>
 10#include <linux/ulpi/regs.h>
 11#include <linux/phy/phy.h>
 12#include <linux/pinctrl/consumer.h>
 13#include <linux/pinctrl/pinctrl-state.h>
 14#include <linux/delay.h>
 15#include <linux/clk.h>
 16
 17#define ULPI_HSIC_CFG		0x30
 18#define ULPI_HSIC_IO_CAL	0x33
 19
 20struct qcom_usb_hsic_phy {
 21	struct ulpi *ulpi;
 22	struct phy *phy;
 23	struct pinctrl *pctl;
 24	struct clk *phy_clk;
 25	struct clk *cal_clk;
 26	struct clk *cal_sleep_clk;
 27};
 28
 29static int qcom_usb_hsic_phy_power_on(struct phy *phy)
 30{
 31	struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
 32	struct ulpi *ulpi = uphy->ulpi;
 33	struct pinctrl_state *pins_default;
 34	int ret;
 35
 36	ret = clk_prepare_enable(uphy->phy_clk);
 37	if (ret)
 38		return ret;
 39
 40	ret = clk_prepare_enable(uphy->cal_clk);
 41	if (ret)
 42		goto err_cal;
 43
 44	ret = clk_prepare_enable(uphy->cal_sleep_clk);
 45	if (ret)
 46		goto err_sleep;
 47
 48	/* Set periodic calibration interval to ~2.048sec in HSIC_IO_CAL_REG */
 49	ret = ulpi_write(ulpi, ULPI_HSIC_IO_CAL, 0xff);
 50	if (ret)
 51		goto err_ulpi;
 52
 53	/* Enable periodic IO calibration in HSIC_CFG register */
 54	ret = ulpi_write(ulpi, ULPI_HSIC_CFG, 0xa8);
 55	if (ret)
 56		goto err_ulpi;
 57
 58	/* Configure pins for HSIC functionality */
 59	pins_default = pinctrl_lookup_state(uphy->pctl, PINCTRL_STATE_DEFAULT);
 60	if (IS_ERR(pins_default))
 61		return PTR_ERR(pins_default);
 62
 63	ret = pinctrl_select_state(uphy->pctl, pins_default);
 64	if (ret)
 65		goto err_ulpi;
 66
 67	 /* Enable HSIC mode in HSIC_CFG register */
 68	ret = ulpi_write(ulpi, ULPI_SET(ULPI_HSIC_CFG), 0x01);
 69	if (ret)
 70		goto err_ulpi;
 71
 72	/* Disable auto-resume */
 73	ret = ulpi_write(ulpi, ULPI_CLR(ULPI_IFC_CTRL),
 74			 ULPI_IFC_CTRL_AUTORESUME);
 75	if (ret)
 76		goto err_ulpi;
 77
 78	return ret;
 79err_ulpi:
 80	clk_disable_unprepare(uphy->cal_sleep_clk);
 81err_sleep:
 82	clk_disable_unprepare(uphy->cal_clk);
 83err_cal:
 84	clk_disable_unprepare(uphy->phy_clk);
 85	return ret;
 86}
 87
 88static int qcom_usb_hsic_phy_power_off(struct phy *phy)
 89{
 90	struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
 91
 92	clk_disable_unprepare(uphy->cal_sleep_clk);
 93	clk_disable_unprepare(uphy->cal_clk);
 94	clk_disable_unprepare(uphy->phy_clk);
 95
 96	return 0;
 97}
 98
 99static const struct phy_ops qcom_usb_hsic_phy_ops = {
100	.power_on = qcom_usb_hsic_phy_power_on,
101	.power_off = qcom_usb_hsic_phy_power_off,
102	.owner = THIS_MODULE,
103};
104
105static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
106{
107	struct qcom_usb_hsic_phy *uphy;
108	struct phy_provider *p;
109	struct clk *clk;
110
111	uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
112	if (!uphy)
113		return -ENOMEM;
114	ulpi_set_drvdata(ulpi, uphy);
115
116	uphy->ulpi = ulpi;
117	uphy->pctl = devm_pinctrl_get(&ulpi->dev);
118	if (IS_ERR(uphy->pctl))
119		return PTR_ERR(uphy->pctl);
120
121	uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
122	if (IS_ERR(clk))
123		return PTR_ERR(clk);
124
125	uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
126	if (IS_ERR(clk))
127		return PTR_ERR(clk);
128
129	uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
130	if (IS_ERR(clk))
131		return PTR_ERR(clk);
132
133	uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
134				    &qcom_usb_hsic_phy_ops);
135	if (IS_ERR(uphy->phy))
136		return PTR_ERR(uphy->phy);
137	phy_set_drvdata(uphy->phy, uphy);
138
139	p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
140	return PTR_ERR_OR_ZERO(p);
141}
142
143static const struct of_device_id qcom_usb_hsic_phy_match[] = {
144	{ .compatible = "qcom,usb-hsic-phy", },
145	{ }
146};
147MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);
148
149static struct ulpi_driver qcom_usb_hsic_phy_driver = {
150	.probe = qcom_usb_hsic_phy_probe,
151	.driver = {
152		.name = "qcom_usb_hsic_phy",
153		.of_match_table = qcom_usb_hsic_phy_match,
154	},
155};
156module_ulpi_driver(qcom_usb_hsic_phy_driver);
157
158MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
159MODULE_LICENSE("GPL v2");