Re: [PATCH 15/21] usb: chipidea: msm: Mux over secondary phy at the right time

[Peter Chen]

On Sun, Jun 26, 2016 at 12:28:32AM -0700, Stephen Boyd wrote:
> We need to pick the correct phy at runtime based on how the SoC
> has been wired onto the board. If the secondary phy is used, take
> it out of reset and mux over to it by writing into the TCSR
> register. Make sure to do this on reset too, because this
> register is reset to the default value (primary phy) after the
> RESET bit is set in USBCMD.
> 

I am curious when you need the secondary phy?

> Cc: Peter Chen <peter.chen@xxxxxxx>
> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <stephen.boyd@xxxxxxxxxx>
> ---
>  drivers/usb/chipidea/ci_hdrc_msm.c | 78 +++++++++++++++++++++++++++++++++++---
>  1 file changed, 73 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/usb/chipidea/ci_hdrc_msm.c b/drivers/usb/chipidea/ci_hdrc_msm.c
> index 40249b0e3e93..df0f8b31db4f 100644
> --- a/drivers/usb/chipidea/ci_hdrc_msm.c
> +++ b/drivers/usb/chipidea/ci_hdrc_msm.c
> @@ -8,30 +8,40 @@
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
> -#include <linux/usb/gadget.h>
>  #include <linux/usb/chipidea.h>
>  #include <linux/clk.h>
>  #include <linux/reset.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/io.h>
>  
>  #include "ci.h"
>  
>  #define HS_PHY_AHB_MODE			0x0098
> +#define HS_PHY_SEC_CTRL			0x0278
> +# define HS_PHY_DIG_CLAMP_N		BIT(16)
>  

One space at the beginning, and keep alignment.

>  struct ci_hdrc_msm {
>  	struct platform_device *ci;
>  	struct clk *core_clk;
>  	struct clk *iface_clk;
> +	bool secondary_phy;
> +	void __iomem *base;
>  };
>  
>  static void ci_hdrc_msm_notify_event(struct ci_hdrc *ci, unsigned event)
>  {
> -	struct device *dev = ci->gadget.dev.parent;
> +	struct device *dev = ci->dev->parent;
> +	struct ci_hdrc_msm *msm_ci = dev_get_drvdata(dev);
>  
>  	switch (event) {
>  	case CI_HDRC_CONTROLLER_RESET_EVENT:
>  		dev_dbg(dev, "CI_HDRC_CONTROLLER_RESET_EVENT received\n");
>  		/* use AHB transactor, allow posted data writes */
>  		hw_write_id_reg(ci, HS_PHY_AHB_MODE, 0xffffffff, 0x8);
> +		if (msm_ci->secondary_phy)
> +			hw_write_id_reg(ci, HS_PHY_SEC_CTRL, HS_PHY_DIG_CLAMP_N,
> +					HS_PHY_DIG_CLAMP_N);
>  		break;
>  	default:
>  		dev_dbg(dev, "unknown ci_hdrc event\n");
> @@ -49,12 +59,58 @@ static struct ci_hdrc_platform_data ci_hdrc_msm_platdata = {
>  	.notify_event		= ci_hdrc_msm_notify_event,
>  };
>  
> +static int ci_hdrc_msm_mux_phy(struct ci_hdrc_msm *ci,
> +			       struct platform_device *pdev)
> +{
> +	struct regmap *regmap;
> +	struct device_node *syscon;
> +	struct device *dev = &pdev->dev;
> +	u32 off, val;
> +	int ret;
> +
> +	syscon = of_parse_phandle(dev->of_node, "phy-select", 0);
> +	if (!syscon)
> +		return 0;
> +
> +	regmap = syscon_node_to_regmap(syscon);
> +	if (IS_ERR(regmap))
> +		return PTR_ERR(regmap);
> +
> +	ret = of_property_read_u32_index(dev->of_node, "phy-select", 1, &off);
> +	if (ret < 0) {
> +		dev_err(dev, "no offset in syscon\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = of_property_read_u32_index(dev->of_node, "phy-select", 2, &val);
> +	if (ret < 0) {
> +		dev_err(dev, "no value in syscon\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = regmap_write(regmap, off, val);
> +	if (ret)
> +		return ret;
> +
> +	ci->secondary_phy = !!val;
> +	if (ci->secondary_phy) {
> +		val = readl_relaxed(ci->base + HS_PHY_SEC_CTRL);
> +		val |= HS_PHY_DIG_CLAMP_N;
> +		writel_relaxed(val, ci->base + HS_PHY_SEC_CTRL);
> +	}
> +
> +	return 0;
> +}
> +
>  static int ci_hdrc_msm_probe(struct platform_device *pdev)
>  {
>  	struct ci_hdrc_msm *ci;
>  	struct platform_device *plat_ci;
>  	struct clk *clk;
>  	struct reset_control *reset;
> +	struct resource *res;
> +	void __iomem *base;
> +	resource_size_t size;
>  	int ret;
>  
>  	dev_dbg(&pdev->dev, "ci_hdrc_msm_probe\n");
> @@ -76,6 +132,15 @@ static int ci_hdrc_msm_probe(struct platform_device *pdev)
>  	if (IS_ERR(clk))
>  		return PTR_ERR(clk);
>  
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res)
> +		return -ENODEV;
> +
> +	size = resource_size(res);
> +	ci->base = base = devm_ioremap(&pdev->dev, res->start, size);
> +	if (!base)
> +		return -ENOMEM;
> +

The core will do the ioremap too, you can't remap io address two times.
The offset larger than 0x200 is vendor specific, you can map it as
the second io region.


>  	reset_control_assert(reset);
>  	usleep_range(10000, 12000);
>  	reset_control_deassert(reset);
> @@ -88,9 +153,12 @@ static int ci_hdrc_msm_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto err_iface;
>  
> -	plat_ci = ci_hdrc_add_device(&pdev->dev,
> -				pdev->resource, pdev->num_resources,
> -				&ci_hdrc_msm_platdata);
> +	ret = ci_hdrc_msm_mux_phy(ci, pdev);
> +	if (ret)
> +		goto err_mux;
> +
> +	plat_ci = ci_hdrc_add_device(&pdev->dev, pdev->resource,
> +				     pdev->num_resources, &ci_hdrc_msm_platdata);
>  	if (IS_ERR(plat_ci)) {
>  		dev_err(&pdev->dev, "ci_hdrc_add_device failed!\n");
>  		ret = PTR_ERR(plat_ci);
> -- 
> 2.9.0.rc2.8.ga28705d
> 
> 
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-- 

Best Regards,
Peter Chen