phy-sun4i-usb: Add support for peripheral-only mode

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>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

1 files changed, 46 insertions, 22 deletions

diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
index 0a45bc6088ae..8c7eb335622e 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
@@ -110,6 +111,7 @@ 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;
@@ -120,6 +122,7 @@ 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)
@@ -432,7 +442,10 @@ 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);
@@ -448,7 +461,8 @@ 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);
@@ -474,7 +488,8 @@ 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);
@@ -519,7 +534,8 @@ 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;
@@ -593,13 +609,17 @@ 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))
@@ -610,9 +630,13 @@ 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];