Re: [PATCH v3 1/3] phy: exynos-dp-video: Use syscon support to control pmu register

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

On Tuesday 16 September 2014 10:32 AM, Vivek Gautam wrote:
> Currently the DP_PHY_ENABLE register is mapped in the driver,
> and accessed to control power to the PHY.
> With mfd-syscon and regmap interface available at our disposal,
> it's wise to use that instead of using a 'reg' property for the
> controller and allocating a memory resource for that.
> 
> To facilitate this, we have added another compatible string
> for Exynso5420 SoC to acquire driver data which contains
> different DP-PHY-CONTROL register offset.
> 
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> Cc: Jingoo Han <jg1.han@samsung.com>
> Cc: Kishon Vijay Abraham I <kishon@ti.com>

Taking this in linux-phy tree. If someone has already taken this patch, please
let me know.

Thanks
Kishon

> ---
> 
> Changes since v2:
>  - Using 'EXYNOS5_PHY_ENABLE' macro instead of 'EXYNOS_DPTX_PHY_ENABLE'
>    since that's available with us in "linux/mfd/syscon/exynos5-pmu.h" file.
> 
> Changes since v1:
>  - state->regs should have been "struct regmap *" instead of
>    "void __iomem *". So corrected the same.
> 
>  .../devicetree/bindings/phy/samsung-phy.txt        |    7 +-
>  drivers/phy/phy-exynos-dp-video.c                  |   79 +++++++++++++-------
>  2 files changed, 59 insertions(+), 27 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/phy/samsung-phy.txt b/Documentation/devicetree/bindings/phy/samsung-phy.txt
> index 7a6feea..15e0f2c 100644
> --- a/Documentation/devicetree/bindings/phy/samsung-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/samsung-phy.txt
> @@ -17,8 +17,11 @@ Samsung EXYNOS SoC series Display Port PHY
>  -------------------------------------------------
>  
>  Required properties:
> -- compatible : should be "samsung,exynos5250-dp-video-phy";
> -- reg : offset and length of the Display Port PHY register set;
> +- compatible : should be one of the following supported values:
> +	 - "samsung,exynos5250-dp-video-phy"
> +	 - "samsung,exynos5420-dp-video-phy"
> +- samsung,pmu-syscon: phandle for PMU system controller interface, used to
> +		      control pmu registers for power isolation.
>  - #phy-cells : from the generic PHY bindings, must be 0;
>  
>  Samsung S5P/EXYNOS SoC series USB PHY
> diff --git a/drivers/phy/phy-exynos-dp-video.c b/drivers/phy/phy-exynos-dp-video.c
> index 8b3026e..53f44a0 100644
> --- a/drivers/phy/phy-exynos-dp-video.c
> +++ b/drivers/phy/phy-exynos-dp-video.c
> @@ -13,44 +13,55 @@
>  #include <linux/io.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/mfd/syscon/exynos5-pmu.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/regmap.h>
>  
> -/* DPTX_PHY_CONTROL register */
> -#define EXYNOS_DPTX_PHY_ENABLE		(1 << 0)
> +struct exynos_dp_video_phy_drvdata {
> +	u32 phy_ctrl_offset;
> +};
>  
>  struct exynos_dp_video_phy {
> -	void __iomem *regs;
> +	struct regmap *regs;
> +	const struct exynos_dp_video_phy_drvdata *drvdata;
>  };
>  
> -static int __set_phy_state(struct exynos_dp_video_phy *state, unsigned int on)
> +static void exynos_dp_video_phy_pwr_isol(struct exynos_dp_video_phy *state,
> +							unsigned int on)
>  {
> -	u32 reg;
> +	unsigned int val;
> +
> +	if (IS_ERR(state->regs))
> +		return;
>  
> -	reg = readl(state->regs);
> -	if (on)
> -		reg |= EXYNOS_DPTX_PHY_ENABLE;
> -	else
> -		reg &= ~EXYNOS_DPTX_PHY_ENABLE;
> -	writel(reg, state->regs);
> +	val = on ? 0 : EXYNOS5_PHY_ENABLE;
>  
> -	return 0;
> +	regmap_update_bits(state->regs, state->drvdata->phy_ctrl_offset,
> +			   EXYNOS5_PHY_ENABLE, val);
>  }
>  
>  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);
> +	/* Disable power isolation on DP-PHY */
> +	exynos_dp_video_phy_pwr_isol(state, 0);
> +
> +	return 0;
>  }
>  
>  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);
> +	/* Enable power isolation on DP-PHY */
> +	exynos_dp_video_phy_pwr_isol(state, 1);
> +
> +	return 0;
>  }
>  
>  static struct phy_ops exynos_dp_video_phy_ops = {
> @@ -59,11 +70,31 @@ static struct phy_ops exynos_dp_video_phy_ops = {
>  	.owner		= THIS_MODULE,
>  };
>  
> +static const struct exynos_dp_video_phy_drvdata exynos5250_dp_video_phy = {
> +	.phy_ctrl_offset	= EXYNOS5_DPTX_PHY_CONTROL,
> +};
> +
> +static const struct exynos_dp_video_phy_drvdata exynos5420_dp_video_phy = {
> +	.phy_ctrl_offset	= EXYNOS5420_DPTX_PHY_CONTROL,
> +};
> +
> +static const struct of_device_id exynos_dp_video_phy_of_match[] = {
> +	{
> +		.compatible = "samsung,exynos5250-dp-video-phy",
> +		.data = &exynos5250_dp_video_phy,
> +	}, {
> +		.compatible = "samsung,exynos5420-dp-video-phy",
> +		.data = &exynos5420_dp_video_phy,
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
> +
>  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;
> +	const struct of_device_id *match;
>  	struct phy_provider *phy_provider;
>  	struct phy *phy;
>  
> @@ -71,11 +102,15 @@ static int exynos_dp_video_phy_probe(struct platform_device *pdev)
>  	if (!state)
>  		return -ENOMEM;
>  
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -
> -	state->regs = devm_ioremap_resource(dev, res);
> -	if (IS_ERR(state->regs))
> +	state->regs = syscon_regmap_lookup_by_phandle(dev->of_node,
> +						      "samsung,pmu-syscon");
> +	if (IS_ERR(state->regs)) {
> +		dev_err(dev, "Failed to lookup PMU regmap\n");
>  		return PTR_ERR(state->regs);
> +	}
> +
> +	match = of_match_node(exynos_dp_video_phy_of_match, dev->of_node);
> +	state->drvdata = match->data;
>  
>  	phy = devm_phy_create(dev, NULL, &exynos_dp_video_phy_ops, NULL);
>  	if (IS_ERR(phy)) {
> @@ -89,12 +124,6 @@ static int exynos_dp_video_phy_probe(struct platform_device *pdev)
>  	return PTR_ERR_OR_ZERO(phy_provider);
>  }
>  
> -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);
> -
>  static struct platform_driver exynos_dp_video_phy_driver = {
>  	.probe	= exynos_dp_video_phy_probe,
>  	.driver = {
>