/*
* Meson GXL and GXM USB2 PHY driver
*
* Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.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.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
/* bits [31:27] are read-only */
#define U2P_R0 0x0
#define U2P_R0_BYPASS_SEL BIT(0)
#define U2P_R0_BYPASS_DM_EN BIT(1)
#define U2P_R0_BYPASS_DP_EN BIT(2)
#define U2P_R0_TXBITSTUFF_ENH BIT(3)
#define U2P_R0_TXBITSTUFF_EN BIT(4)
#define U2P_R0_DM_PULLDOWN BIT(5)
#define U2P_R0_DP_PULLDOWN BIT(6)
#define U2P_R0_DP_VBUS_VLD_EXT_SEL BIT(7)
#define U2P_R0_DP_VBUS_VLD_EXT BIT(8)
#define U2P_R0_ADP_PRB_EN BIT(9)
#define U2P_R0_ADP_DISCHARGE BIT(10)
#define U2P_R0_ADP_CHARGE BIT(11)
#define U2P_R0_DRV_VBUS BIT(12)
#define U2P_R0_ID_PULLUP BIT(13)
#define U2P_R0_LOOPBACK_EN_B BIT(14)
#define U2P_R0_OTG_DISABLE BIT(15)
#define U2P_R0_COMMON_ONN BIT(16)
#define U2P_R0_FSEL_MASK GENMASK(19, 17)
#define U2P_R0_REF_CLK_SEL_MASK GENMASK(21, 20)
#define U2P_R0_POWER_ON_RESET BIT(22)
#define U2P_R0_V_ATE_TEST_EN_B_MASK GENMASK(24, 23)
#define U2P_R0_ID_SET_ID_DQ BIT(25)
#define U2P_R0_ATE_RESET BIT(26)
#define U2P_R0_FSV_MINUS BIT(27)
#define U2P_R0_FSV_PLUS BIT(28)
#define U2P_R0_BYPASS_DM_DATA BIT(29)
#define U2P_R0_BYPASS_DP_DATA BIT(30)
#define U2P_R1 0x4
#define U2P_R1_BURN_IN_TEST BIT(0)
#define U2P_R1_ACA_ENABLE BIT(1)
#define U2P_R1_DCD_ENABLE BIT(2)
#define U2P_R1_VDAT_SRC_EN_B BIT(3)
#define U2P_R1_VDAT_DET_EN_B BIT(4)
#define U2P_R1_CHARGES_SEL BIT(5)
#define U2P_R1_TX_PREEMP_PULSE_TUNE BIT(6)
#define U2P_R1_TX_PREEMP_AMP_TUNE_MASK GENMASK(8, 7)
#define U2P_R1_TX_RES_TUNE_MASK GENMASK(10, 9)
#define U2P_R1_TX_RISE_TUNE_MASK GENMASK(12, 11)
#define U2P_R1_TX_VREF_TUNE_MASK GENMASK(16, 13)
#define U2P_R1_TX_FSLS_TUNE_MASK GENMASK(20, 17)
#define U2P_R1_TX_HSXV_TUNE_MASK GENMASK(22, 21)
#define U2P_R1_OTG_TUNE_MASK GENMASK(25, 23)
#define U2P_R1_SQRX_TUNE_MASK GENMASK(28, 26)
#define U2P_R1_COMP_DIS_TUNE_MASK GENMASK(31, 29)
/* bits [31:14] are read-only */
#define U2P_R2 0x8
#define U2P_R2_TESTDATA_IN_MASK GENMASK(7, 0)
#define U2P_R2_TESTADDR_MASK GENMASK(11, 8)
#define U2P_R2_TESTDATA_OUT_SEL BIT(12)
#define U2P_R2_TESTCLK BIT(13)
#define U2P_R2_TESTDATA_OUT_MASK GENMASK(17, 14)
#define U2P_R2_ACA_PIN_RANGE_C BIT(18)
#define U2P_R2_ACA_PIN_RANGE_B BIT(19)
#define U2P_R2_ACA_PIN_RANGE_A BIT(20)
#define U2P_R2_ACA_PIN_GND BIT(21)
#define U2P_R2_ACA_PIN_FLOAT BIT(22)
#define U2P_R2_CHARGE_DETECT BIT(23)
#define U2P_R2_DEVICE_SESSION_VALID BIT(24)
#define U2P_R2_ADP_PROBE BIT(25)
#define U2P_R2_ADP_SENSE BIT(26)
#define U2P_R2_SESSION_END BIT(27)
#define U2P_R2_VBUS_VALID BIT(28)
#define U2P_R2_B_VALID BIT(29)
#define U2P_R2_A_VALID BIT(30)
#define U2P_R2_ID_DIG BIT(31)
#define U2P_R3 0xc
#define RESET_COMPLETE_TIME 500
struct phy_meson_gxl_usb2_priv {
struct regmap *regmap;
enum phy_mode mode;
int is_enabled;
struct clk *clk;
struct reset_control *reset;
};
static const struct regmap_config phy_meson_gxl_usb2_regmap_conf = {
.reg_bits = 8,
.val_bits = 32,
.reg_stride = 4,
.max_register = U2P_R3,
};
static int phy_meson_gxl_usb2_init(struct phy *phy)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
int ret;
ret = reset_control_reset(priv->reset);
if (ret)
return ret;
ret = clk_prepare_enable(priv->clk);
if (ret)
return ret;
return 0;
}
static int phy_meson_gxl_usb2_exit(struct phy *phy)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
clk_disable_unprepare(priv->clk);
return 0;
}
static int phy_meson_gxl_usb2_reset(struct phy *phy)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
if (priv->is_enabled) {
/* reset the PHY and wait until settings are stabilized */
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
U2P_R0_POWER_ON_RESET);
udelay(RESET_COMPLETE_TIME);
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
0);
udelay(RESET_COMPLETE_TIME);
}
return 0;
}
static int phy_meson_gxl_usb2_set_mode(struct phy *phy, enum phy_mode mode)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
switch (mode) {
case PHY_MODE_USB_HOST:
case PHY_MODE_USB_OTG:
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
U2P_R0_DM_PULLDOWN);
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
U2P_R0_DP_PULLDOWN);
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP, 0);
break;
case PHY_MODE_USB_DEVICE:
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DM_PULLDOWN,
0);
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_DP_PULLDOWN,
0);
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_ID_PULLUP,
U2P_R0_ID_PULLUP);
break;
default:
return -EINVAL;
}
phy_meson_gxl_usb2_reset(phy);
priv->mode = mode;
return 0;
}
static int phy_meson_gxl_usb2_power_off(struct phy *phy)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
priv->is_enabled = 0;
/* power off the PHY by putting it into reset mode */
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET,
U2P_R0_POWER_ON_RESET);
return 0;
}
static int phy_meson_gxl_usb2_power_on(struct phy *phy)
{
struct phy_meson_gxl_usb2_priv *priv = phy_get_drvdata(phy);
int ret;
priv->is_enabled = 1;
/* power on the PHY by taking it out of reset mode */
regmap_update_bits(priv->regmap, U2P_R0, U2P_R0_POWER_ON_RESET, 0);
ret = phy_meson_gxl_usb2_set_mode(phy, priv->mode);
if (ret) {
phy_meson_gxl_usb2_power_off(phy);
dev_err(&phy->dev, "Failed to initialize PHY with mode %d\n",
priv->mode);
return ret;
}
return 0;
}
static const struct phy_ops phy_meson_gxl_usb2_ops = {
.init = phy_meson_gxl_usb2_init,
.exit = phy_meson_gxl_usb2_exit,
.power_on = phy_meson_gxl_usb2_power_on,
.power_off = phy_meson_gxl_usb2_power_off,
.set_mode = phy_meson_gxl_usb2_set_mode,
.reset = phy_meson_gxl_usb2_reset,
.owner = THIS_MODULE,
};
static int phy_meson_gxl_usb2_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct phy_provider *phy_provider;
struct resource *res;
struct phy_meson_gxl_usb2_priv *priv;
struct phy *phy;
void __iomem *base;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
platform_set_drvdata(pdev, priv);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
/* start in host mode */
priv->mode = PHY_MODE_USB_HOST;
priv->regmap = devm_regmap_init_mmio(dev, base,
&phy_meson_gxl_usb2_regmap_conf);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
priv->clk = devm_clk_get(dev, "phy");
if (IS_ERR(priv->clk)) {
ret = PTR_ERR(priv->clk);
if (ret == -ENOENT)
priv->clk = NULL;
else
return ret;
}
priv->reset = devm_reset_control_get_optional_shared(dev, "phy");
if (IS_ERR(priv->reset))
return PTR_ERR(priv->reset);
phy = devm_phy_create(dev, NULL, &phy_meson_gxl_usb2_ops);
if (IS_ERR(phy)) {
ret = PTR_ERR(phy);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to create PHY\n");
return ret;
}
phy_set_drvdata(phy, priv);
phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id phy_meson_gxl_usb2_of_match[] = {
{ .compatible = "amlogic,meson-gxl-usb2-phy", },
{ },
};
MODULE_DEVICE_TABLE(of, phy_meson_gxl_usb2_of_match);
static struct platform_driver phy_meson_gxl_usb2_driver = {
.probe = phy_meson_gxl_usb2_probe,
.driver = {
.name = "phy-meson-gxl-usb2",
.of_match_table = phy_meson_gxl_usb2_of_match,
},
};
module_platform_driver(phy_meson_gxl_usb2_driver);
MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
MODULE_DESCRIPTION("Meson GXL and GXM USB2 PHY driver");
MODULE_LICENSE("GPL v2");