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

Heiko Stübner
2015-10-12T16:18:41Z

Am Montag, 12. Oktober 2015, 20:32:47 schrieb Kishon Vijay Abraham I:
> 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 at 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?

Rockchip's GRF syscon registers use what gets called "Hiword-mask", so when
writing you actually need to set the write-enable bit (x+16, like
GRF_EDP_PHY_SIDDQ_WRITE_EN here) if you want to set bit x. No other bits get
affected by this.

Heiko