linux/drivers/phy/phy-rockchip-dp.c
Heiko Stuebner 0311c76e47 phy: rockchip-dp: should be a child device of the GRF
The displayport-phy is fully enclosed in the general register files (GRF).
Therefore as seen from the device-tree it shouldn't be a separate platform-
device but instead a sub-device of the GRF - using the simply-mfd mechanism.

The driver entered the kernel in the current merge-window, so we can still
adapt the binding without needing a fallback, as the binding hasn't been
released with a full kernel yet.

While the edp phy is fully part of the GRF, it doesn't have any separate
register set there, so doesn't get any register-area assigned.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Yakir Yang <ykk@rock-chips.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
2016-04-13 18:33:05 +05:30

155 lines
3.7 KiB
C

/*
* Rockchip DP PHY driver
*
* Copyright (C) 2016 FuZhou Rockchip Co., Ltd.
* Author: Yakir Yang <ykk@@rock-chips.com>
*
* 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.
*/
#include <linux/clk.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>
#define GRF_SOC_CON12 0x0274
#define GRF_EDP_REF_CLK_SEL_INTER_HIWORD_MASK BIT(20)
#define GRF_EDP_REF_CLK_SEL_INTER BIT(4)
#define GRF_EDP_PHY_SIDDQ_HIWORD_MASK BIT(21)
#define GRF_EDP_PHY_SIDDQ_ON 0
#define GRF_EDP_PHY_SIDDQ_OFF BIT(5)
struct rockchip_dp_phy {
struct device *dev;
struct regmap *grf;
struct clk *phy_24m;
};
static int rockchip_set_phy_state(struct phy *phy, bool enable)
{
struct rockchip_dp_phy *dp = phy_get_drvdata(phy);
int ret;
if (enable) {
ret = regmap_write(dp->grf, GRF_SOC_CON12,
GRF_EDP_PHY_SIDDQ_HIWORD_MASK |
GRF_EDP_PHY_SIDDQ_ON);
if (ret < 0) {
dev_err(dp->dev, "Can't enable PHY power %d\n", ret);
return ret;
}
ret = clk_prepare_enable(dp->phy_24m);
} else {
clk_disable_unprepare(dp->phy_24m);
ret = regmap_write(dp->grf, GRF_SOC_CON12,
GRF_EDP_PHY_SIDDQ_HIWORD_MASK |
GRF_EDP_PHY_SIDDQ_OFF);
}
return ret;
}
static int rockchip_dp_phy_power_on(struct phy *phy)
{
return rockchip_set_phy_state(phy, true);
}
static int rockchip_dp_phy_power_off(struct phy *phy)
{
return rockchip_set_phy_state(phy, false);
}
static const struct phy_ops rockchip_dp_phy_ops = {
.power_on = rockchip_dp_phy_power_on,
.power_off = rockchip_dp_phy_power_off,
.owner = THIS_MODULE,
};
static int rockchip_dp_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct phy_provider *phy_provider;
struct rockchip_dp_phy *dp;
struct phy *phy;
int ret;
if (!np)
return -ENODEV;
if (!dev->parent || !dev->parent->of_node)
return -ENODEV;
dp = devm_kzalloc(dev, sizeof(*dp), GFP_KERNEL);
if (IS_ERR(dp))
return -ENOMEM;
dp->dev = dev;
dp->phy_24m = devm_clk_get(dev, "24m");
if (IS_ERR(dp->phy_24m)) {
dev_err(dev, "cannot get clock 24m\n");
return PTR_ERR(dp->phy_24m);
}
ret = clk_set_rate(dp->phy_24m, 24000000);
if (ret < 0) {
dev_err(dp->dev, "cannot set clock phy_24m %d\n", ret);
return ret;
}
dp->grf = syscon_node_to_regmap(dev->parent->of_node);
if (IS_ERR(dp->grf)) {
dev_err(dev, "rk3288-dp needs the General Register Files syscon\n");
return PTR_ERR(dp->grf);
}
ret = regmap_write(dp->grf, GRF_SOC_CON12, GRF_EDP_REF_CLK_SEL_INTER |
GRF_EDP_REF_CLK_SEL_INTER_HIWORD_MASK);
if (ret != 0) {
dev_err(dp->dev, "Could not config GRF edp ref clk: %d\n", ret);
return ret;
}
phy = devm_phy_create(dev, np, &rockchip_dp_phy_ops);
if (IS_ERR(phy)) {
dev_err(dev, "failed to create phy\n");
return PTR_ERR(phy);
}
phy_set_drvdata(phy, dp);
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_dp_phy_dt_ids[] = {
{ .compatible = "rockchip,rk3288-dp-phy" },
{}
};
MODULE_DEVICE_TABLE(of, rockchip_dp_phy_dt_ids);
static struct platform_driver rockchip_dp_phy_driver = {
.probe = rockchip_dp_phy_probe,
.driver = {
.name = "rockchip-dp-phy",
.of_match_table = rockchip_dp_phy_dt_ids,
},
};
module_platform_driver(rockchip_dp_phy_driver);
MODULE_AUTHOR("Yakir Yang <ykk@rock-chips.com>");
MODULE_DESCRIPTION("Rockchip DP PHY driver");
MODULE_LICENSE("GPL v2");