[PATCH 1/3] phy: Add driver for Exynos DP PHY
Jingoo Han
jg1.han at samsung.com
Fri Jun 28 01:54:06 EDT 2013
On Friday, June 28, 2013 2:31 PM, Kishon Vijay Abraham I wrote:
>
> Hi,
>
> On Friday 28 June 2013 10:52 AM, Jingoo Han wrote:
> > Add a PHY provider driver for the Samsung Exynos SoC DP PHY.
> >
> > Signed-off-by: Jingoo Han <jg1.han at samsung.com>
> > ---
> > .../phy/samsung,exynos5250-dp-video-phy.txt | 7 ++
> > drivers/phy/Kconfig | 8 ++
> > drivers/phy/Makefile | 3 +-
> > drivers/phy/phy-exynos-dp-video.c | 130 ++++++++++++++++++++
> > 4 files changed, 147 insertions(+), 1 deletion(-)
> > create mode 100644 Documentation/devicetree/bindings/phy/samsung,exynos5250-dp-video-phy.txt
> > create mode 100644 drivers/phy/phy-exynos-dp-video.c
> >
> > diff --git a/Documentation/devicetree/bindings/phy/samsung,exynos5250-dp-video-phy.txt
> > b/Documentation/devicetree/bindings/phy/samsung,exynos5250-dp-video-phy.txt
> > new file mode 100644
> > index 0000000..8b6fa79
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/phy/samsung,exynos5250-dp-video-phy.txt
> > @@ -0,0 +1,7 @@
> > +Samsung EXYNOS SoC series DP PHY
> > +-------------------------------------------------
> > +
> > +Required properties:
> > +- compatible : should be "samsung,exynos5250-dp-video-phy";
> > +- reg : offset and length of the DP PHY register set;
> > +- #phy-cells : from the generic phy bindings, must be 1;
> > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> > index 5f85909..6d10e3b 100644
> > --- a/drivers/phy/Kconfig
> > +++ b/drivers/phy/Kconfig
> > @@ -11,3 +11,11 @@ menuconfig GENERIC_PHY
> > devices present in the kernel. This layer will have the generic
> > API by which phy drivers can create PHY using the phy framework and
> > phy users can obtain reference to the PHY.
> > +
> > +if GENERIC_PHY
> > +
> > +config PHY_EXYNOS_DP_VIDEO
> > + tristate "EXYNOS SoC series DP PHY driver"
> > + help
> > + Support for DP PHY found on Samsung EXYNOS SoCs.
> > +endif
> > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> > index 9e9560f..d8d861c 100644
> > --- a/drivers/phy/Makefile
> > +++ b/drivers/phy/Makefile
> > @@ -2,4 +2,5 @@
> > # Makefile for the phy drivers.
> > #
> >
> > -obj-$(CONFIG_GENERIC_PHY) += phy-core.o
> > +obj-$(CONFIG_GENERIC_PHY) += phy-core.o
> > +obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO) += phy-exynos-dp-video.o
> > diff --git a/drivers/phy/phy-exynos-dp-video.c b/drivers/phy/phy-exynos-dp-video.c
> > new file mode 100644
> > index 0000000..376b3bc2
> > --- /dev/null
> > +++ b/drivers/phy/phy-exynos-dp-video.c
> > @@ -0,0 +1,130 @@
> > +/*
> > + * Samsung EXYNOS SoC series DP PHY driver
> > + *
> > + * Copyright (C) 2013 Samsung Electronics Co., Ltd.
> > + * Author: Jingoo Han <jg1.han at samsung.com>
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> > + * it under the terms of the GNU General Public License version 2 as
> > + * published by the Free Software Foundation.
> > + */
> > +
> > +#include <linux/delay.h>
>
> this header file is not needed here.
OK, I will remove it.
>
> > +#include <linux/io.h>
> > +#include <linux/kernel.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/spinlock.h>
> > +
> > +/* DPTX_PHY_CONTROL register */
> > +#define EXYNOS_DPTX_PHY_ENABLE (1 << 0)
> > +
> > +struct exynos_dp_video_phy {
> > + spinlock_t slock;
> > + struct phy *phys;
> > + void __iomem *regs;
> > +};
> > +
> > +static int __set_phy_state(struct exynos_dp_video_phy *state, unsigned int on)
> > +{
> > + void __iomem *addr;
> > + unsigned long flags;
> > + u32 reg;
> > +
> > + addr = state->regs;
> > +
> > + spin_lock_irqsave(&state->slock, flags);
> > + reg = readl(addr);
> > + if (on)
> > + reg |= EXYNOS_DPTX_PHY_ENABLE;
> > + else
> > + reg &= ~EXYNOS_DPTX_PHY_ENABLE;
> > + writel(reg, addr);
> > + spin_unlock_irqrestore(&state->slock, flags);
> > + return 0;
> > +}
> > +
> > +static int exynos_dp_video_phy_power_on(struct phy *phy)
> > +{
> > + struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
> > +
> > + return __set_phy_state(state, 1);
> > +}
> > +
> > +static int exynos_dp_video_phy_power_off(struct phy *phy)
> > +{
> > + struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
> > +
> > + return __set_phy_state(state, 0);
> > +}
> > +
> > +static struct phy *exynos_dp_video_phy_xlate(struct device *dev,
> > + struct of_phandle_args *args)
> > +{
> > + struct exynos_dp_video_phy *state = dev_get_drvdata(dev);
> > +
> > + return state->phys;
>
> you can instead use of_phy_simple_xlate for such simple cases.
OK, I will use of_phy_simple_xlate().
> > +}
> > +
> > +static struct phy_ops exynos_dp_video_phy_ops = {
> > + .power_on = exynos_dp_video_phy_power_on,
> > + .power_off = exynos_dp_video_phy_power_off,
> > + .owner = THIS_MODULE,
> > +};
> > +
> > +static int exynos_dp_video_phy_probe(struct platform_device *pdev)
> > +{
> > + struct exynos_dp_video_phy *state;
> > + struct device *dev = &pdev->dev;
> > + struct resource *res;
> > + struct phy_provider *phy_provider;
> > +
> > + state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
> > + if (!state)
> > + return -ENOMEM;
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +
> > + state->regs = devm_ioremap_resource(dev, res);
> > + if (IS_ERR(state->regs))
> > + return PTR_ERR(state->regs);
> > +
> > + dev_set_drvdata(dev, state);
> > +
> > + phy_provider = devm_of_phy_provider_register(dev,
> > + exynos_dp_video_phy_xlate);
> > + if (IS_ERR(phy_provider))
> > + return PTR_ERR(phy_provider);
> > +
> > + state->phys = devm_phy_create(dev, 0, &exynos_dp_video_phy_ops, "dp");
> > + if (IS_ERR(state->phys)) {
> > + dev_err(dev, "failed to create DP PHY\n");
> > + return PTR_ERR(state->phys);
> > + }
> > + phy_set_drvdata(state->phys, state);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id exynos_dp_video_phy_of_match[] = {
> > + { .compatible = "samsung,exynos5250-dp-video-phy" },
> > + { },
> > +};
> > +MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
>
> This above should come inside #ifdef CONFIG_OF.
OK, I will add '#ifdef CONFIG_OF'.
> > +
> > +static struct platform_driver exynos_dp_video_phy_driver = {
> > + .probe = exynos_dp_video_phy_probe,
>
> missing .remove?
No, it is intentional.
In the exynos_dp_video_phy_probe(), only devm_*() are called as below.
devm_kzalloc(),
devm_ioremap_resource(),
devm_of_phy_provider_register(),
devm_phy_create(),
Also, dev_set_drvdata(dev, NULL), phy_set_drvdata(state->phys, NULL)
are not necessary in remove(), because driver core clears automatically
after device_release.
Thus, there is no functions in the remove().
Thank you for your comment. :)
It is very helpful.
Best regards,
Jingoo Han
> > + .driver = {
> > + .of_match_table = exynos_dp_video_phy_of_match,
> > + .name = "exynos-dp-video-phy",
> > + .owner = THIS_MODULE,
> > + }
> > +};
> > +module_platform_driver(exynos_dp_video_phy_driver);
> > +
> > +MODULE_DESCRIPTION("Samsung EXYNOS SoC DP PHY driver");
> > +MODULE_AUTHOR("Jingoo Han <jg1.han at samsung.com>");
> > +MODULE_LICENSE("GPL v2");
>
> Thanks
> Kishon
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