Subject: [PATCH v3 5/8] phy: rockchip-usb: expose the phy-internal PLLs

From: [email-masked] (Kishon Vijay Abraham I)
Date: Tue, 15 Dec 2015 16:23:24 +0530

Hi Mike,

On Friday 20 November 2015 02:52 AM, Heiko Stuebner wrote:
> The USB phys on Rockchip SoCs contain their own internal PLLs to create
> the 480MHz needed. Additionally this PLL output is also fed back into the
> core clock-controller as possible source for clocks like the GPU or others.
> 
> Until now this was modelled incorrectly with a "virtual" factor clock in
> the clock controller. The one big caveat is that if we turn off the usb phy
> via the siddq signal, all analog components get turned off, including the
> PLLs. It is therefore possible that a source clock gets disabled without
> the clock driver ever knowing, possibly making the system hang.
> 
> Therefore register the phy-plls as real clocks that the clock driver can
> then reference again normally, making the clock hirarchy finally reflect
> the actual hardware.
> 
> The phy-ops get converted to simply turning that new clock on and off
> which in turn controls the siddq signal of the phy.
> 
> Through this the driver gains handling for platform-specific data, to
> handle the phy->clock name association.

Are you okay with this patch/ Can you give your Acked-by?

Thanks
Kishon

> 
> Signed-off-by: Heiko Stuebner <[email-masked]>
> Reviewed-by: Douglas Anderson <[email-masked]>
> ---
>  .../devicetree/bindings/phy/rockchip-usb-phy.txt   |   1 +
>  drivers/phy/phy-rockchip-usb.c                     | 188 ++++++++++++++++++---
>  2 files changed, 162 insertions(+), 27 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> index 9b37242..68498d5 100644
> --- a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
> @@ -24,6 +24,7 @@ required properties:
>  Optional Properties:
>  - clocks : phandle + clock specifier for the phy clocks
>  - clock-names: string, clock name, must be "phyclk"
> +- #clock-cells: for users of the phy-pll, should be 0
>  
>  Example:
>  
> diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
> index 16cd533..33a80eb 100644
> --- a/drivers/phy/phy-rockchip-usb.c
> +++ b/drivers/phy/phy-rockchip-usb.c
> @@ -15,12 +15,14 @@
>   */
>  
>  #include <linux/clk.h>
> +#include <linux/clk-provider.h>
>  #include <linux/io.h>
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/mutex.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
> +#include <linux/of_platform.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  #include <linux/regulator/consumer.h>
> @@ -36,15 +38,28 @@
>  #define SIDDQ_ON		BIT(13)
>  #define SIDDQ_OFF		(0 << 13)
>  
> +struct rockchip_usb_phys {
> +	int reg;
> +	const char *pll_name;
> +};
> +
> +struct rockchip_usb_phy_pdata {
> +	struct rockchip_usb_phys *phys;
> +};
> +
>  struct rockchip_usb_phy_base {
>  	struct device *dev;
>  	struct regmap *reg_base;
> +	const struct rockchip_usb_phy_pdata *pdata;
>  };
>  
>  struct rockchip_usb_phy {
>  	struct rockchip_usb_phy_base *base;
> +	struct device_node *np;
>  	unsigned int	reg_offset;
>  	struct clk	*clk;
> +	struct clk      *clk480m;
> +	struct clk_hw	clk480m_hw;
>  	struct phy	*phy;
>  };
>  
> @@ -55,17 +70,59 @@ static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
>  			    SIDDQ_WRITE_ENA | (siddq ? SIDDQ_ON : SIDDQ_OFF));
>  }
>  
> -static int rockchip_usb_phy_power_off(struct phy *_phy)
> +static unsigned long rockchip_usb_phy480m_recalc_rate(struct clk_hw *hw,
> +						unsigned long parent_rate)
>  {
> -	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> -	int ret = 0;
> +	return 480000000;
> +}
> +
> +static void rockchip_usb_phy480m_disable(struct clk_hw *hw)
> +{
> +	struct rockchip_usb_phy *phy = container_of(hw,
> +						    struct rockchip_usb_phy,
> +						    clk480m_hw);
>  
>  	/* Power down usb phy analog blocks by set siddq 1 */
> -	ret = rockchip_usb_phy_power(phy, 1);
> -	if (ret)
> +	rockchip_usb_phy_power(phy, 1);
> +}
> +
> +static int rockchip_usb_phy480m_enable(struct clk_hw *hw)
> +{
> +	struct rockchip_usb_phy *phy = container_of(hw,
> +						    struct rockchip_usb_phy,
> +						    clk480m_hw);
> +
> +	/* Power up usb phy analog blocks by set siddq 0 */
> +	return rockchip_usb_phy_power(phy, 0);
> +}
> +
> +static int rockchip_usb_phy480m_is_enabled(struct clk_hw *hw)
> +{
> +	struct rockchip_usb_phy *phy = container_of(hw,
> +						    struct rockchip_usb_phy,
> +						    clk480m_hw);
> +	int ret;
> +	u32 val;
> +
> +	ret = regmap_read(phy->base->reg_base, phy->reg_offset, &val);
> +	if (ret < 0)
>  		return ret;
>  
> -	clk_disable_unprepare(phy->clk);
> +	return (val & SIDDQ_ON) ? 0 : 1;
> +}
> +
> +static const struct clk_ops rockchip_usb_phy480m_ops = {
> +	.enable = rockchip_usb_phy480m_enable,
> +	.disable = rockchip_usb_phy480m_disable,
> +	.is_enabled = rockchip_usb_phy480m_is_enabled,
> +	.recalc_rate = rockchip_usb_phy480m_recalc_rate,
> +};
> +
> +static int rockchip_usb_phy_power_off(struct phy *_phy)
> +{
> +	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +	clk_disable_unprepare(phy->clk480m);
>  
>  	return 0;
>  }
> @@ -73,20 +130,8 @@ static int rockchip_usb_phy_power_off(struct phy *_phy)
>  static int rockchip_usb_phy_power_on(struct phy *_phy)
>  {
>  	struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
> -	int ret = 0;
>  
> -	ret = clk_prepare_enable(phy->clk);
> -	if (ret)
> -		return ret;
> -
> -	/* Power up usb phy analog blocks by set siddq 0 */
> -	ret = rockchip_usb_phy_power(phy, 0);
> -	if (ret) {
> -		clk_disable_unprepare(phy->clk);
> -		return ret;
> -	}
> -
> -	return 0;
> +	return clk_prepare_enable(phy->clk480m);
>  }
>  
>  static const struct phy_ops ops = {
> @@ -99,6 +144,9 @@ static void rockchip_usb_phy_action(void *data)
>  {
>  	struct rockchip_usb_phy *rk_phy = data;
>  
> +	of_clk_del_provider(rk_phy->np);
> +	clk_unregister(rk_phy->clk480m);
> +
>  	if (rk_phy->clk)
>  		clk_put(rk_phy->clk);
>  }
> @@ -108,13 +156,16 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
>  {
>  	struct rockchip_usb_phy *rk_phy;
>  	unsigned int reg_offset;
> -	int err;
> +	const char *clk_name;
> +	struct clk_init_data init;
> +	int err, i;
>  
>  	rk_phy = devm_kzalloc(base->dev, sizeof(*rk_phy), GFP_KERNEL);
>  	if (!rk_phy)
>  		return -ENOMEM;
>  
>  	rk_phy->base = base;
> +	rk_phy->np = child;
>  
>  	if (of_property_read_u32(child, "reg", &reg_offset)) {
>  		dev_err(base->dev, "missing reg property in node %s\n",
> @@ -124,14 +175,54 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
>  
>  	rk_phy->reg_offset = reg_offset;
>  
> -	err = devm_add_action(base->dev, rockchip_usb_phy_action, rk_phy);
> -	if (err)
> -		return err;
> -
>  	rk_phy->clk = of_clk_get_by_name(child, "phyclk");
>  	if (IS_ERR(rk_phy->clk))
>  		rk_phy->clk = NULL;
>  
> +	i = 0;
> +	init.name = NULL;
> +	while (base->pdata->phys[i].reg) {
> +		if (base->pdata->phys[i].reg == reg_offset) {
> +			init.name = base->pdata->phys[i].pll_name;
> +			break;
> +		}
> +		i++;
> +	}
> +
> +	if (!init.name) {
> +		dev_err(base->dev, "phy data not found\n");
> +		return -EINVAL;
> +	}
> +
> +	if (rk_phy->clk) {
> +		clk_name = __clk_get_name(rk_phy->clk);
> +		init.flags = 0;
> +		init.parent_names = &clk_name;
> +		init.num_parents = 1;
> +	} else {
> +		init.flags = CLK_IS_ROOT;
> +		init.parent_names = NULL;
> +		init.num_parents = 0;
> +	}
> +
> +	init.ops = &rockchip_usb_phy480m_ops;
> +	rk_phy->clk480m_hw.init = &init;
> +
> +	rk_phy->clk480m = clk_register(base->dev, &rk_phy->clk480m_hw);
> +	if (IS_ERR(rk_phy->clk480m)) {
> +		err = PTR_ERR(rk_phy->clk480m);
> +		goto err_clk;
> +	}
> +
> +	err = of_clk_add_provider(child, of_clk_src_simple_get,
> +				  rk_phy->clk480m);
> +	if (err < 0)
> +		goto err_clk_prov;
> +
> +	err = devm_add_action(base->dev, rockchip_usb_phy_action, rk_phy);
> +	if (err)
> +		goto err_devm_action;
> +
>  	rk_phy->phy = devm_phy_create(base->dev, child, &ops);
>  	if (IS_ERR(rk_phy->phy)) {
>  		dev_err(base->dev, "failed to create PHY\n");
> @@ -141,13 +232,48 @@ static int rockchip_usb_phy_init(struct rockchip_usb_phy_base *base,
>  
>  	/* only power up usb phy when it use, so disable it when init*/
>  	return rockchip_usb_phy_power(rk_phy, 1);
> +
> +err_devm_action:
> +	of_clk_del_provider(child);
> +err_clk_prov:
> +	clk_unregister(rk_phy->clk480m);
> +err_clk:
> +	if (rk_phy->clk)
> +		clk_put(rk_phy->clk);
> +	return err;
>  }
>  
> +static const struct rockchip_usb_phy_pdata rk3066a_pdata = {
> +	.phys = (struct rockchip_usb_phys[]){
> +		{ .reg = 0x17c, .pll_name = "sclk_otgphy0_480m" },
> +		{ .reg = 0x188, .pll_name = "sclk_otgphy1_480m" },
> +		{ /* sentinel */ }
> +	},
> +};
> +
> +static const struct rockchip_usb_phy_pdata rk3188_pdata = {
> +	.phys = (struct rockchip_usb_phys[]){
> +		{ .reg = 0x10c, .pll_name = "sclk_otgphy0_480m" },
> +		{ .reg = 0x11c, .pll_name = "sclk_otgphy1_480m" },
> +		{ /* sentinel */ }
> +	},
> +};
> +
> +static const struct rockchip_usb_phy_pdata rk3288_pdata = {
> +	.phys = (struct rockchip_usb_phys[]){
> +		{ .reg = 0x320, .pll_name = "sclk_otgphy0_480m" },
> +		{ .reg = 0x334, .pll_name = "sclk_otgphy1_480m" },
> +		{ .reg = 0x348, .pll_name = "sclk_otgphy2_480m" },
> +		{ /* sentinel */ }
> +	},
> +};
> +
>  static int rockchip_usb_phy_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct rockchip_usb_phy_base *phy_base;
>  	struct phy_provider *phy_provider;
> +	const struct of_device_id *match;
>  	struct device_node *child;
>  	int err;
>  
> @@ -155,6 +281,14 @@ static int rockchip_usb_phy_probe(struct platform_device *pdev)
>  	if (!phy_base)
>  		return -ENOMEM;
>  
> +	match = of_match_device(dev->driver->of_match_table, dev);
> +	if (!match || !match->data) {
> +		dev_err(dev, "missing phy data\n");
> +		return -EINVAL;
> +	}
> +
> +	phy_base->pdata = match->data;
> +
>  	phy_base->dev = dev;
>  	phy_base->reg_base = syscon_regmap_lookup_by_phandle(dev->of_node,
>  							     "rockchip,grf");
> @@ -176,9 +310,9 @@ static int rockchip_usb_phy_probe(struct platform_device *pdev)
>  }
>  
>  static const struct of_device_id rockchip_usb_phy_dt_ids[] = {
> -	{ .compatible = "rockchip,rk3066a-usb-phy" },
> -	{ .compatible = "rockchip,rk3188-usb-phy" },
> -	{ .compatible = "rockchip,rk3288-usb-phy" },
> +	{ .compatible = "rockchip,rk3066a-usb-phy", .data = &rk3066a_pdata },
> +	{ .compatible = "rockchip,rk3188-usb-phy", .data = &rk3188_pdata },
> +	{ .compatible = "rockchip,rk3288-usb-phy", .data = &rk3288_pdata },
>  	{}
>  };
>  
>