diff options
Diffstat (limited to 'drivers/phy/phy-rockchip-emmc.c')
| -rw-r--r-- | drivers/phy/phy-rockchip-emmc.c | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c new file mode 100644 index 000000000000..6ebcf3e41c46 --- /dev/null +++ b/drivers/phy/phy-rockchip-emmc.c @@ -0,0 +1,232 @@ +/* + * Rockchip emmc PHY driver + * + * Copyright (C) 2016 Shawn Lin <shawn.lin@rock-chips.com> + * Copyright (C) 2016 ROCKCHIP, Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/delay.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/phy/phy.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +/* + * The higher 16-bit of this register is used for write protection + * only if BIT(x + 16) set to 1 the BIT(x) can be written. + */ +#define HIWORD_UPDATE(val, mask, shift) \ + ((val) << (shift) | (mask) << ((shift) + 16)) + +/* Register definition */ +#define GRF_EMMCPHY_CON0 0x0 +#define GRF_EMMCPHY_CON1 0x4 +#define GRF_EMMCPHY_CON2 0x8 +#define GRF_EMMCPHY_CON3 0xc +#define GRF_EMMCPHY_CON4 0x10 +#define GRF_EMMCPHY_CON5 0x14 +#define GRF_EMMCPHY_CON6 0x18 +#define GRF_EMMCPHY_STATUS 0x20 + +#define PHYCTRL_PDB_MASK 0x1 +#define PHYCTRL_PDB_SHIFT 0x0 +#define PHYCTRL_PDB_PWR_ON 0x1 +#define PHYCTRL_PDB_PWR_OFF 0x0 +#define PHYCTRL_ENDLL_MASK 0x1 +#define PHYCTRL_ENDLL_SHIFT 0x1 +#define PHYCTRL_ENDLL_ENABLE 0x1 +#define PHYCTRL_ENDLL_DISABLE 0x0 +#define PHYCTRL_CALDONE_MASK 0x1 +#define PHYCTRL_CALDONE_SHIFT 0x6 +#define PHYCTRL_CALDONE_DONE 0x1 +#define PHYCTRL_CALDONE_GOING 0x0 +#define PHYCTRL_DLLRDY_MASK 0x1 +#define PHYCTRL_DLLRDY_SHIFT 0x5 +#define PHYCTRL_DLLRDY_DONE 0x1 +#define PHYCTRL_DLLRDY_GOING 0x0 + +struct rockchip_emmc_phy { + unsigned int reg_offset; + struct regmap *reg_base; +}; + +static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy, + bool on_off) +{ + unsigned int caldone; + unsigned int dllrdy; + + /* + * Keep phyctrl_pdb and phyctrl_endll low to allow + * initialization of CALIO state M/C DFFs + */ + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON6, + HIWORD_UPDATE(PHYCTRL_PDB_PWR_OFF, + PHYCTRL_PDB_MASK, + PHYCTRL_PDB_SHIFT)); + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON6, + HIWORD_UPDATE(PHYCTRL_ENDLL_DISABLE, + PHYCTRL_ENDLL_MASK, + PHYCTRL_ENDLL_SHIFT)); + + /* Already finish power_off above */ + if (on_off == PHYCTRL_PDB_PWR_OFF) + return 0; + + /* + * According to the user manual, calpad calibration + * cycle takes more than 2us without the minimal recommended + * value, so we may need a little margin here + */ + udelay(3); + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON6, + HIWORD_UPDATE(PHYCTRL_PDB_PWR_ON, + PHYCTRL_PDB_MASK, + PHYCTRL_PDB_SHIFT)); + + /* + * According to the user manual, it asks driver to + * wait 5us for calpad busy trimming + */ + udelay(5); + regmap_read(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_STATUS, + &caldone); + caldone = (caldone >> PHYCTRL_CALDONE_SHIFT) & PHYCTRL_CALDONE_MASK; + if (caldone != PHYCTRL_CALDONE_DONE) { + pr_err("rockchip_emmc_phy_power: caldone timeout.\n"); + return -ETIMEDOUT; + } + + regmap_write(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_CON6, + HIWORD_UPDATE(PHYCTRL_ENDLL_ENABLE, + PHYCTRL_ENDLL_MASK, + PHYCTRL_ENDLL_SHIFT)); + /* + * After enable analog DLL circuits, we need extra 10.2us + * for dll to be ready for work. + */ + udelay(11); + regmap_read(rk_phy->reg_base, + rk_phy->reg_offset + GRF_EMMCPHY_STATUS, + &dllrdy); + dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK; + if (dllrdy != PHYCTRL_DLLRDY_DONE) { + pr_err("rockchip_emmc_phy_power: dllrdy timeout.\n"); + return -ETIMEDOUT; + } + + return 0; +} + +static int rockchip_emmc_phy_power_off(struct phy *phy) +{ + struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); + int ret = 0; + + /* Power down emmc phy analog blocks */ + ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF); + if (ret) + return ret; + + return 0; +} + +static int rockchip_emmc_phy_power_on(struct phy *phy) +{ + struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy); + int ret = 0; + + /* Power up emmc phy analog blocks */ + ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON); + if (ret) + return ret; + + return 0; +} + +static const struct phy_ops ops = { + .power_on = rockchip_emmc_phy_power_on, + .power_off = rockchip_emmc_phy_power_off, + .owner = THIS_MODULE, +}; + +static int rockchip_emmc_phy_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rockchip_emmc_phy *rk_phy; + struct phy *generic_phy; + struct phy_provider *phy_provider; + struct regmap *grf; + unsigned int reg_offset; + + if (!dev->parent || !dev->parent->of_node) + return -ENODEV; + + grf = syscon_node_to_regmap(dev->parent->of_node); + if (IS_ERR(grf)) { + dev_err(dev, "Missing rockchip,grf property\n"); + return PTR_ERR(grf); + } + + rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL); + if (!rk_phy) + return -ENOMEM; + + if (of_property_read_u32(dev->of_node, "reg", ®_offset)) { + dev_err(dev, "missing reg property in node %s\n", + dev->of_node->name); + return -EINVAL; + } + + rk_phy->reg_offset = reg_offset; + rk_phy->reg_base = grf; + + generic_phy = devm_phy_create(dev, dev->of_node, &ops); + if (IS_ERR(generic_phy)) { + dev_err(dev, "failed to create PHY\n"); + return PTR_ERR(generic_phy); + } + + phy_set_drvdata(generic_phy, rk_phy); + 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 rockchip_emmc_phy_dt_ids[] = { + { .compatible = "rockchip,rk3399-emmc-phy" }, + {} +}; + +MODULE_DEVICE_TABLE(of, rockchip_emmc_phy_dt_ids); + +static struct platform_driver rockchip_emmc_driver = { + .probe = rockchip_emmc_phy_probe, + .driver = { + .name = "rockchip-emmc-phy", + .of_match_table = rockchip_emmc_phy_dt_ids, + }, +}; + +module_platform_driver(rockchip_emmc_driver); + +MODULE_AUTHOR("Shawn Lin <shawn.lin@rock-chips.com>"); +MODULE_DESCRIPTION("Rockchip EMMC PHY driver"); +MODULE_LICENSE("GPL v2"); |