Re: [PATCH v6 10/17] phy: Add driver for rockchip Display Port PHY

[Kishon Vijay Abraham I <kishon@ti.com>]

Hi,

On Saturday 10 October 2015 09:25 PM, Yakir Yang wrote:
> This phy driver would control the Rockchip DisplayPort module
> phy clock and phy power, it is relate to analogix_dp-rockchip
> dp driver. If you want DP works rightly on rockchip platform,
> then you should select both of them.

Add phy driver for the Rockchip DisplayPort PHY module. This is required
to get DisplayPort working in Rockchip SoCs.
> 
> Signed-off-by: Yakir Yang <ykk@rock-chips.com>
> ---
> 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 | 151 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 159 insertions(+)
>  create mode 100644 drivers/phy/phy-rockchip-dp.c
> 
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 47da573..8f2bc4f 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -310,6 +310,13 @@ 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 a5b18c1..e281f35 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -34,6 +34,7 @@ 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..3a2ac120
> --- /dev/null
> +++ b/drivers/phy/phy-rockchip-dp.c
> @@ -0,0 +1,151 @@
> +/*
> + * 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	BIT(4)
> +#define GRF_EDP_PHY_SIDDQ_WRITE_EN      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 = clk_prepare_enable(dp->phy_24m);
> +		if (ret < 0) {
> +			dev_err(dp->dev, "Can't enable clock 24m %d\n", ret);
> +			return ret;
> +		}
> +
> +		ret = regmap_write(dp->grf, GRF_SOC_CON12,
> +				   GRF_EDP_PHY_SIDDQ_WRITE_EN |
> +				   GRF_EDP_PHY_SIDDQ_ON);
> +	} else {
> +		clk_disable_unprepare(dp->phy_24m);

should clk_disable come after regmap_write? It'll be symmetric to enable?
> +		ret = regmap_write(dp->grf, GRF_SOC_CON12,
> +				   GRF_EDP_PHY_SIDDQ_WRITE_EN |
> +				   GRF_EDP_PHY_SIDDQ_OFF);

Is this syscon register used only by Display Port PHY? Better to use
regmap_update API?

Thanks
Kishon