diff options
Diffstat (limited to 'drivers/phy/amlogic/phy-meson-axg-pcie.c')
| -rw-r--r-- | drivers/phy/amlogic/phy-meson-axg-pcie.c | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/drivers/phy/amlogic/phy-meson-axg-pcie.c b/drivers/phy/amlogic/phy-meson-axg-pcie.c new file mode 100644 index 000000000..2299bab38 --- /dev/null +++ b/drivers/phy/amlogic/phy-meson-axg-pcie.c @@ -0,0 +1,190 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Amlogic AXG PCIE PHY driver + * + * Copyright (C) 2020 Remi Pommarel <repk@triplefau.lt> + */ +#include <linux/module.h> +#include <linux/phy/phy.h> +#include <linux/regmap.h> +#include <linux/reset.h> +#include <linux/platform_device.h> +#include <linux/bitfield.h> +#include <dt-bindings/phy/phy.h> + +#define MESON_PCIE_REG0 0x00 +#define MESON_PCIE_COMMON_CLK BIT(4) +#define MESON_PCIE_PORT_SEL GENMASK(3, 2) +#define MESON_PCIE_CLK BIT(1) +#define MESON_PCIE_POWERDOWN BIT(0) + +#define MESON_PCIE_TWO_X1 FIELD_PREP(MESON_PCIE_PORT_SEL, 0x3) +#define MESON_PCIE_COMMON_REF_CLK FIELD_PREP(MESON_PCIE_COMMON_CLK, 0x1) +#define MESON_PCIE_PHY_INIT (MESON_PCIE_TWO_X1 | \ + MESON_PCIE_COMMON_REF_CLK) +#define MESON_PCIE_RESET_DELAY 500 + +struct phy_axg_pcie_priv { + struct phy *phy; + struct phy *analog; + struct regmap *regmap; + struct reset_control *reset; +}; + +static const struct regmap_config phy_axg_pcie_regmap_conf = { + .reg_bits = 8, + .val_bits = 32, + .reg_stride = 4, + .max_register = MESON_PCIE_REG0, +}; + +static int phy_axg_pcie_power_on(struct phy *phy) +{ + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy); + int ret; + + ret = phy_power_on(priv->analog); + if (ret != 0) + return ret; + + regmap_update_bits(priv->regmap, MESON_PCIE_REG0, + MESON_PCIE_POWERDOWN, 0); + return 0; +} + +static int phy_axg_pcie_power_off(struct phy *phy) +{ + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy); + int ret; + + ret = phy_power_off(priv->analog); + if (ret != 0) + return ret; + + regmap_update_bits(priv->regmap, MESON_PCIE_REG0, + MESON_PCIE_POWERDOWN, 1); + return 0; +} + +static int phy_axg_pcie_init(struct phy *phy) +{ + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy); + int ret; + + ret = phy_init(priv->analog); + if (ret != 0) + return ret; + + regmap_write(priv->regmap, MESON_PCIE_REG0, MESON_PCIE_PHY_INIT); + return reset_control_reset(priv->reset); +} + +static int phy_axg_pcie_exit(struct phy *phy) +{ + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy); + int ret; + + ret = phy_exit(priv->analog); + if (ret != 0) + return ret; + + return reset_control_reset(priv->reset); +} + +static int phy_axg_pcie_reset(struct phy *phy) +{ + struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy); + int ret = 0; + + ret = phy_reset(priv->analog); + if (ret != 0) + goto out; + + ret = reset_control_assert(priv->reset); + if (ret != 0) + goto out; + udelay(MESON_PCIE_RESET_DELAY); + + ret = reset_control_deassert(priv->reset); + if (ret != 0) + goto out; + udelay(MESON_PCIE_RESET_DELAY); + +out: + return ret; +} + +static const struct phy_ops phy_axg_pcie_ops = { + .init = phy_axg_pcie_init, + .exit = phy_axg_pcie_exit, + .power_on = phy_axg_pcie_power_on, + .power_off = phy_axg_pcie_power_off, + .reset = phy_axg_pcie_reset, + .owner = THIS_MODULE, +}; + +static int phy_axg_pcie_probe(struct platform_device *pdev) +{ + struct phy_provider *pphy; + struct device *dev = &pdev->dev; + struct phy_axg_pcie_priv *priv; + struct device_node *np = dev->of_node; + void __iomem *base; + int ret; + + priv = devm_kmalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->phy = devm_phy_create(dev, np, &phy_axg_pcie_ops); + if (IS_ERR(priv->phy)) { + ret = PTR_ERR(priv->phy); + if (ret != -EPROBE_DEFER) + dev_err(dev, "failed to create PHY\n"); + return ret; + } + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + priv->regmap = devm_regmap_init_mmio(dev, base, + &phy_axg_pcie_regmap_conf); + if (IS_ERR(priv->regmap)) + return PTR_ERR(priv->regmap); + + priv->reset = devm_reset_control_array_get_exclusive(dev); + if (IS_ERR(priv->reset)) + return PTR_ERR(priv->reset); + + priv->analog = devm_phy_get(dev, "analog"); + if (IS_ERR(priv->analog)) + return PTR_ERR(priv->analog); + + phy_set_drvdata(priv->phy, priv); + dev_set_drvdata(dev, priv); + pphy = devm_of_phy_provider_register(dev, of_phy_simple_xlate); + + return PTR_ERR_OR_ZERO(pphy); +} + +static const struct of_device_id phy_axg_pcie_of_match[] = { + { + .compatible = "amlogic,axg-pcie-phy", + }, + { }, +}; +MODULE_DEVICE_TABLE(of, phy_axg_pcie_of_match); + +static struct platform_driver phy_axg_pcie_driver = { + .probe = phy_axg_pcie_probe, + .driver = { + .name = "phy-axg-pcie", + .of_match_table = phy_axg_pcie_of_match, + }, +}; +module_platform_driver(phy_axg_pcie_driver); + +MODULE_AUTHOR("Remi Pommarel <repk@triplefau.lt>"); +MODULE_DESCRIPTION("Amlogic AXG PCIE PHY driver"); +MODULE_LICENSE("GPL v2"); |