[PATCH v3 2/4] phy-sun4i-usb: Add support for peripheral-only mode

[kishon@ti.com (Kishon Vijay Abraham I)]

On Sunday 05 June 2016 08:29 PM, Hans de Goede wrote:
> Use the new of_usb_get_dr_mode_by_phy() function to get the dr_mode
> from the musb controller node instead of assuming that having an id_det
> gpio means otg mode, and not having one means host mode.
> 
> Implement peripheral-only mode by adding a sun4i_usb_phy0_get_id_det
> helper which looks at the dr_mode, always registering our extcon and
> always monitoring vbus.
> 
> If dr_mode is not specified in the dts, do not register phy0 as we then
> do not know how to treat it. This is actually a good thing as this means
> we will not be registering phy0 on devices where the otg controller is
> not enabled in the devicetree.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
> Changes in v2:
> -Adjust for of_usb_get_dr_mode_by_phy now taking an args0 parameter
> Changes in v3:
> -Only toggle the phy vbus-det bit on id-change on systems without vbus-det
>  when in otg mode
> ---
>  drivers/phy/phy-sun4i-usb.c | 68 ++++++++++++++++++++++++++++++---------------
>  1 file changed, 46 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
> index bae54f7..e3cbaae 100644
> --- a/drivers/phy/phy-sun4i-usb.c
> +++ b/drivers/phy/phy-sun4i-usb.c
> @@ -40,6 +40,7 @@
>  #include <linux/power_supply.h>
>  #include <linux/regulator/consumer.h>
>  #include <linux/reset.h>
> +#include <linux/usb/of.h>
>  #include <linux/workqueue.h>
>  
>  #define REG_ISCR			0x00
> @@ -109,6 +110,7 @@ struct sun4i_usb_phy_cfg {
>  struct sun4i_usb_phy_data {
>  	void __iomem *base;
>  	const struct sun4i_usb_phy_cfg *cfg;
> +	enum usb_dr_mode dr_mode;
>  	struct mutex mutex;
>  	struct sun4i_usb_phy {
>  		struct phy *phy;
> @@ -119,6 +121,7 @@ struct sun4i_usb_phy_data {
>  		bool regulator_on;
>  		int index;
>  	} phys[MAX_PHYS];
> +	int first_phy;
>  	/* phy0 / otg related variables */
>  	struct extcon_dev *extcon;
>  	bool phy0_init;
> @@ -285,16 +288,10 @@ static int sun4i_usb_phy_init(struct phy *_phy)
>  		sun4i_usb_phy0_update_iscr(_phy, 0, ISCR_DPDM_PULLUP_EN);
>  		sun4i_usb_phy0_update_iscr(_phy, 0, ISCR_ID_PULLUP_EN);
>  
> -		if (data->id_det_gpio) {
> -			/* OTG mode, force ISCR and cable state updates */
> -			data->id_det = -1;
> -			data->vbus_det = -1;
> -			queue_delayed_work(system_wq, &data->detect, 0);
> -		} else {
> -			/* Host only mode */
> -			sun4i_usb_phy0_set_id_detect(_phy, 0);
> -			sun4i_usb_phy0_set_vbus_detect(_phy, 1);
> -		}
> +		/* Force ISCR and cable state updates */
> +		data->id_det = -1;
> +		data->vbus_det = -1;
> +		queue_delayed_work(system_wq, &data->detect, 0);
>  	}
>  
>  	return 0;
> @@ -319,6 +316,19 @@ static int sun4i_usb_phy_exit(struct phy *_phy)
>  	return 0;
>  }
>  
> +static int sun4i_usb_phy0_get_id_det(struct sun4i_usb_phy_data *data)
> +{
> +	switch (data->dr_mode) {
> +	case USB_DR_MODE_OTG:
> +		return gpiod_get_value_cansleep(data->id_det_gpio);
> +	case USB_DR_MODE_HOST:
> +		return 0;
> +	case USB_DR_MODE_PERIPHERAL:
> +	default:
> +		return 1;
> +	}
> +}
> +
>  static int sun4i_usb_phy0_get_vbus_det(struct sun4i_usb_phy_data *data)
>  {
>  	if (data->vbus_det_gpio)
> @@ -414,7 +424,10 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
>  	struct phy *phy0 = data->phys[0].phy;
>  	int id_det, vbus_det, id_notify = 0, vbus_notify = 0;
>  
> -	id_det = gpiod_get_value_cansleep(data->id_det_gpio);
> +	if (phy0 == NULL)
> +		return;
> +
> +	id_det = sun4i_usb_phy0_get_id_det(data);
>  	vbus_det = sun4i_usb_phy0_get_vbus_det(data);
>  
>  	mutex_lock(&phy0->mutex);
> @@ -430,7 +443,8 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
>  		 * without vbus detection report vbus low for long enough for
>  		 * the musb-ip to end the current device session.
>  		 */
> -		if (!sun4i_usb_phy0_have_vbus_det(data) && id_det == 0) {
> +		if (data->dr_mode == USB_DR_MODE_OTG &&
> +		    !sun4i_usb_phy0_have_vbus_det(data) && id_det == 0) {
>  			sun4i_usb_phy0_set_vbus_detect(phy0, 0);
>  			msleep(200);
>  			sun4i_usb_phy0_set_vbus_detect(phy0, 1);
> @@ -456,7 +470,8 @@ static void sun4i_usb_phy0_id_vbus_det_scan(struct work_struct *work)
>  		 * without vbus detection report vbus low for long enough to
>  		 * the musb-ip to end the current host session.
>  		 */
> -		if (!sun4i_usb_phy0_have_vbus_det(data) && id_det == 1) {
> +		if (data->dr_mode == USB_DR_MODE_OTG &&
> +		    !sun4i_usb_phy0_have_vbus_det(data) && id_det == 1) {
>  			mutex_lock(&phy0->mutex);
>  			sun4i_usb_phy0_set_vbus_detect(phy0, 0);
>  			msleep(1000);
> @@ -501,7 +516,8 @@ static struct phy *sun4i_usb_phy_xlate(struct device *dev,
>  {
>  	struct sun4i_usb_phy_data *data = dev_get_drvdata(dev);
>  
> -	if (args->args[0] >= data->cfg->num_phys)
> +	if (args->args[0] < data->first_phy ||
> +	    args->args[0] >= data->cfg->num_phys)
>  		return ERR_PTR(-ENODEV);
>  
>  	return data->phys[args->args[0]].phy;
> @@ -575,13 +591,17 @@ static int sun4i_usb_phy_probe(struct platform_device *pdev)
>  			return -EPROBE_DEFER;
>  	}
>  
> -	/* vbus_det without id_det makes no sense, and is not supported */
> -	if (sun4i_usb_phy0_have_vbus_det(data) && !data->id_det_gpio) {
> -		dev_err(dev, "usb0_id_det missing or invalid\n");
> -		return -ENODEV;
> -	}
> -
> -	if (data->id_det_gpio) {
> +	data->dr_mode = of_usb_get_dr_mode_by_phy(np, 0);
> +	switch (data->dr_mode) {
> +	case USB_DR_MODE_OTG:
> +		/* otg without id_det makes no sense, and is not supported */
> +		if (!data->id_det_gpio) {
> +			dev_err(dev, "usb0_id_det missing or invalid\n");
> +			return -ENODEV;
> +		}
> +		/* fall through */
> +	case USB_DR_MODE_HOST:
> +	case USB_DR_MODE_PERIPHERAL:
>  		data->extcon = devm_extcon_dev_allocate(dev,
>  							sun4i_usb_phy0_cable);
>  		if (IS_ERR(data->extcon))
> @@ -592,9 +612,13 @@ static int sun4i_usb_phy_probe(struct platform_device *pdev)
>  			dev_err(dev, "failed to register extcon: %d\n", ret);
>  			return ret;
>  		}
> +		break;
> +	default:
> +		dev_info(dev, "dr_mode unknown, not registering usb phy0\n");
> +		data->first_phy = 1;
>  	}
>  
> -	for (i = 0; i < data->cfg->num_phys; i++) {
> +	for (i = data->first_phy; i < data->cfg->num_phys; i++) {
>  		struct sun4i_usb_phy *phy = data->phys + i;
>  		char name[16];
>  
>