[PATCH] usb: imx-us-phy: add vbus_valid ro parameter

[Ahmad Fatoum]

Hello Marco,

On 24.08.21 12:46, Marco Felsch wrote:
> The parameter can be used by init scripts to detect a plugged usb cable.
> Upon a plugged usb cable the barebox behaviour can be changed which can
> be useful e.g. during production to apply a special production
> environment.
> 
> Signed-off-by: Marco Felsch <m.felsch at pengutronix.de>
> ---
>  drivers/usb/imx/imx-usb-phy.c | 34 +++++++++++++++++++++++++++++++++-
>  1 file changed, 33 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/imx/imx-usb-phy.c b/drivers/usb/imx/imx-usb-phy.c
> index 32098ef248..9420c8c109 100644
> --- a/drivers/usb/imx/imx-usb-phy.c
> +++ b/drivers/usb/imx/imx-usb-phy.c
> @@ -37,9 +37,12 @@
>  #define BM_USBPHY_CTRL_ENHOSTDISCONDETECT	BIT(1)
>  
>  #define ANADIG_USB1_CHRG_DETECT_SET		0x1b4
> -#define ANADIG_USB2_CHRG_DETECT_SET		0x214
>  #define ANADIG_USB1_CHRG_DETECT_EN_B		BIT(20)
>  #define ANADIG_USB1_CHRG_DETECT_CHK_CHRG_B	BIT(19)
> +#define ANADIG_USB1_VBUS_DETECT_STAT		0x1c0
> +#define ANADIG_USB1_VBUS_DETECT_STAT_VBUS_VALID	BIT(3)
> +#define ANADIG_USB2_CHRG_DETECT_SET		0x214
> +#define ANADIG_USB2_VBUS_DETECT_STAT		0x220
>  
>  struct imx_usbphy {
>  	struct usb_phy usb_phy;
> @@ -132,6 +135,27 @@ static const struct phy_ops imx_phy_ops = {
>  	.to_usbphy = imx_usbphy_to_usbphy,
>  };
>  
> +/* Albeit the access can only happen serial use two variables */
> +unsigned int vbus_valid_usb1;
> +unsigned int vbus_valid_usb2;
> +
> +static int imx_usbphy_get_vbus_state(struct param_d *p, void *priv)
> +{
> +	struct imx_usbphy *imxphy = priv;
> +	unsigned int *vbus_valid;
> +	unsigned int reg, val;
> +
> +	reg = imxphy->port_id ?
> +		ANADIG_USB1_VBUS_DETECT_STAT :
> +		ANADIG_USB2_VBUS_DETECT_STAT;
> +	val = readl(imxphy->anatop + reg);
> +
> +	vbus_valid = imxphy->port_id ? &vbus_valid_usb1 : &vbus_valid_usb2;
> +	*vbus_valid = !!(val & ANADIG_USB1_VBUS_DETECT_STAT_VBUS_VALID);
> +
> +	return 0;
> +}
> +
>  static int imx_usbphy_probe(struct device_d *dev)
>  {
>  	struct resource *iores;
> @@ -149,11 +173,19 @@ static int imx_usbphy_probe(struct device_d *dev)
>  	imxphy->port_id = ret;
>  
>  	if (of_get_property(np, "fsl,anatop", NULL)) {
> +		unsigned int *vbus_valid = imxphy->port_id ?
> +			&vbus_valid_usb1 :
> +			&vbus_valid_usb2;

Can you allocate this in imxphy? That way you avoid globals
and don't hardcode the existance of only two phys into the driver.

> +
>  		imxphy->anatop =
>  			syscon_base_lookup_by_phandle(np, "fsl,anatop");
>  		ret = PTR_ERR_OR_ZERO(imxphy->anatop);
>  		if (ret)
>  			goto err_free;
> +
> +		dev_add_param_bool(dev, "vbus_valid", param_set_readonly,
> +				   imx_usbphy_get_vbus_state, vbus_valid,
> +				   imxphy);

I assume valid == usb port is in gadget mode and host is supplying vbus?
What happens when port is in host mode? A comment explaining this would
be nice.

>  	}
>  
>  	iores = dev_request_mem_resource(dev, 0);
> 


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