Re: [PATCH v8 10/17] phy: Add driver for rockchip Display Port PHY

[Heiko Stuebner <heiko@sntech.de>]

Hi Yakir,

Am Mittwoch, 28. Oktober 2015, 16:30:33 schrieb Yakir Yang:
> Add phy driver for the Rockchip DisplayPort PHY module. This
> is required to get DisplayPort working in Rockchip SoCs.
> 
> Reviewed-by: Heiko Stuebner <heiko@sntech.de>
> Signed-off-by: Yakir Yang <ykk@rock-chips.com>

a general thing I have been pondering, we should probably move the
dp-phy under the GRF. Similar to the new power-domains being
a full child of the PMU, the dp-phy is a full child-device of the GRF.

That would include:
- making the GRF a simply-mfd (just adding that property)
- moving the dts node under it
- making the driver get its regmap from its parent (just like
  drivers/soc/rockchip/pm_domains.c does)


The usbphy is another example of that, and I think I'll be moving it
below the grf as well.


Heiko

> ---
> Changes in v8:
> - Fix the mixed spacers on macro definitions. (Heiko)
> - Remove the unnecessary empty line after clk_prepare_enable. (Heiko)
> 
> Changes in v7:
> - Simply the commit message. (Kishon)
> - Symmetrical enable/disbale the phy clock and power. (Kishon)
> 
> Changes in v6: None
> Changes in v5:
> - Remove "reg" DT property, cause driver could poweron/poweroff phy via
>   the exist "grf" syscon already. And rename the example DT node from
>   "edp_phy: phy@ff770274" to "edp_phy: edp-phy" directly. (Heiko)
> - Add deivce_node at the front of driver, update phy_ops type from "static
>   struct" to "static const struct". And correct the input paramters of
>   devm_phy_create() interfaces. (Heiko)
> 
> Changes in v4:
> - Add commit message, and remove the redundant rockchip_dp_phy_init()
>   function, move those code to probe() method. And remove driver .owner
>   number. (Kishon)
> 
> Changes in v3:
> - Suggest, add rockchip dp phy driver, collect the phy clocks and
>   power control. (Heiko)
> 
> Changes in v2: None
> 
>  drivers/phy/Kconfig           |   7 ++
>  drivers/phy/Makefile          |   1 +
>  drivers/phy/phy-rockchip-dp.c | 155 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 163 insertions(+)
>  create mode 100644 drivers/phy/phy-rockchip-dp.c
> 
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 7eb5859d..7355819 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -319,6 +319,13 @@ config PHY_ROCKCHIP_USB
>  	help
>  	  Enable this to support the Rockchip USB 2.0 PHY.
>  
> +config PHY_ROCKCHIP_DP
> +	tristate "Rockchip Display Port PHY Driver"
> +	depends on ARCH_ROCKCHIP && OF
> +	select GENERIC_PHY
> +	help
> +	  Enable this to support the Rockchip Display Port PHY.
> +
>  config PHY_ST_SPEAR1310_MIPHY
>  	tristate "ST SPEAR1310-MIPHY driver"
>  	select GENERIC_PHY
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 075db1a..b1700cd 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -35,6 +35,7 @@ phy-exynos-usb2-$(CONFIG_PHY_S5PV210_USB2)	+= phy-s5pv210-usb2.o
>  obj-$(CONFIG_PHY_EXYNOS5_USBDRD)	+= phy-exynos5-usbdrd.o
>  obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)	+= phy-qcom-apq8064-sata.o
>  obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
> +obj-$(CONFIG_PHY_ROCKCHIP_DP)		+= phy-rockchip-dp.o
>  obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)	+= phy-qcom-ipq806x-sata.o
>  obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY)	+= phy-spear1310-miphy.o
>  obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY)	+= phy-spear1340-miphy.o
> diff --git a/drivers/phy/phy-rockchip-dp.c b/drivers/phy/phy-rockchip-dp.c
> new file mode 100644
> index 0000000..c82c22f
> --- /dev/null
> +++ b/drivers/phy/phy-rockchip-dp.c
> @@ -0,0 +1,155 @@
> +/*
> + * Rockchip DP PHY driver
> + *
> + * Copyright (C) 2015 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/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/clk.h>
> +#include <linux/phy/phy.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/platform_device.h>
> +
> +#define GRF_SOC_CON12                           0x0274
> +
> +#define GRF_EDP_REF_CLK_SEL_INTER_HIWORD_MASK   BIT(4)
> +#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 resource *res;
> +	struct phy *phy;
> +	int ret;
> +
> +	if (!np)
> +		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_regmap_lookup_by_phandle(np, "rockchip,grf");
> +	if (IS_ERR(dp->grf)) {
> +		dev_err(dev, "rk3288-dp needs rockchip,grf property\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");
>