usb: xhci: tegra: Add genpd support

The generic power-domain framework has been updated to allow devices
that require more than one power-domain to create a new device for
each power-domain required and then link these new power-domain
devices to the consumer device.

Update the Tegra xHCI driver to use the new APIs provided by the
generic power-domain framework so we can use the generic power-domain
framework for managing the xHCI controllers power-domains. Please
note that to maintain backward compatibility with older device-tree
blobs these new generic power-domain APIs are only used if the
'power-domains' property is present and otherwise we fall back to
using the legacy Tegra APIs for managing the power-domains.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 77 insertions, 12 deletions

diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 920a50a54095..6b5db344de30 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -18,6 +18,7 @@
 #include <linux/phy/tegra/xusb.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
+#include <linux/pm_domain.h>
 #include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
 #include <linux/reset.h>
@@ -194,6 +195,11 @@ struct tegra_xusb {
         struct reset_control *host_rst;
         struct reset_control *ss_rst;
 
+        struct device *genpd_dev_host;
+        struct device *genpd_dev_ss;
+        struct device_link *genpd_dl_host;
+        struct device_link *genpd_dl_ss;
+
         struct phy **phys;
         unsigned int num_phys;
 
@@ -928,6 +934,57 @@ static int tegra_xusb_load_firmware(struct tegra_xusb *tegra)
         return 0;
 }
 
+static void tegra_xusb_powerdomain_remove(struct device *dev,
+                                          struct tegra_xusb *tegra)
+{
+        if (tegra->genpd_dl_ss)
+                device_link_del(tegra->genpd_dl_ss);
+        if (tegra->genpd_dl_host)
+                device_link_del(tegra->genpd_dl_host);
+        if (tegra->genpd_dev_ss)
+                dev_pm_domain_detach(tegra->genpd_dev_ss, true);
+        if (tegra->genpd_dev_host)
+                dev_pm_domain_detach(tegra->genpd_dev_host, true);
+}
+
+static int tegra_xusb_powerdomain_init(struct device *dev,
+                                       struct tegra_xusb *tegra)
+{
+        int err;
+
+        tegra->genpd_dev_host = dev_pm_domain_attach_by_name(dev, "xusb_host");
+        if (IS_ERR(tegra->genpd_dev_host)) {
+                err = PTR_ERR(tegra->genpd_dev_host);
+                dev_err(dev, "failed to get host pm-domain: %d\n", err);
+                return err;
+        }
+
+        tegra->genpd_dev_ss = dev_pm_domain_attach_by_name(dev, "xusb_ss");
+        if (IS_ERR(tegra->genpd_dev_ss)) {
+                err = PTR_ERR(tegra->genpd_dev_ss);
+                dev_err(dev, "failed to get superspeed pm-domain: %d\n", err);
+                return err;
+        }
+
+        tegra->genpd_dl_host = device_link_add(dev, tegra->genpd_dev_host,
+                                               DL_FLAG_PM_RUNTIME |
+                                               DL_FLAG_STATELESS);
+        if (!tegra->genpd_dl_host) {
+                dev_err(dev, "adding host device link failed!\n");
+                return -ENODEV;
+        }
+
+        tegra->genpd_dl_ss = device_link_add(dev, tegra->genpd_dev_ss,
+                                             DL_FLAG_PM_RUNTIME |
+                                             DL_FLAG_STATELESS);
+        if (!tegra->genpd_dl_ss) {
+                dev_err(dev, "adding superspeed device link failed!\n");
+                return -ENODEV;
+        }
+
+        return 0;
+}
+
 static int tegra_xusb_probe(struct platform_device *pdev)
 {
         struct tegra_xusb_mbox_msg msg;
@@ -1038,7 +1095,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                 goto put_padctl;
         }
 
-        if (!pdev->dev.pm_domain) {
+        if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
                 tegra->host_rst = devm_reset_control_get(&pdev->dev,
                                                          "xusb_host");
                 if (IS_ERR(tegra->host_rst)) {
@@ -1069,17 +1126,22 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                                                         tegra->host_clk,
                                                         tegra->host_rst);
                 if (err) {
+                        tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
                         dev_err(&pdev->dev,
                                 "failed to enable XUSBC domain: %d\n", err);
-                        goto disable_xusba;
+                        goto put_padctl;
                 }
+        } else {
+                err = tegra_xusb_powerdomain_init(&pdev->dev, tegra);
+                if (err)
+                        goto put_powerdomains;
         }
 
         tegra->supplies = devm_kcalloc(&pdev->dev, tegra->soc->num_supplies,
                                        sizeof(*tegra->supplies), GFP_KERNEL);
         if (!tegra->supplies) {
                 err = -ENOMEM;
-                goto disable_xusbc;
+                goto put_powerdomains;
         }
 
         for (i = 0; i < tegra->soc->num_supplies; i++)
@@ -1089,7 +1151,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                                       tegra->supplies);
         if (err) {
                 dev_err(&pdev->dev, "failed to get regulators: %d\n", err);
-                goto disable_xusbc;
+                goto put_powerdomains;
         }
 
         for (i = 0; i < tegra->soc->num_types; i++)
@@ -1099,7 +1161,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                                    sizeof(*tegra->phys), GFP_KERNEL);
         if (!tegra->phys) {
                 err = -ENOMEM;
-                goto disable_xusbc;
+                goto put_powerdomains;
         }
 
         for (i = 0, k = 0; i < tegra->soc->num_types; i++) {
@@ -1115,7 +1177,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                                         "failed to get PHY %s: %ld\n", prop,
                                         PTR_ERR(phy));
                                 err = PTR_ERR(phy);
-                                goto disable_xusbc;
+                                goto put_powerdomains;
                         }
 
                         tegra->phys[k++] = phy;
@@ -1126,7 +1188,7 @@ static int tegra_xusb_probe(struct platform_device *pdev)
                                     dev_name(&pdev->dev));
         if (!tegra->hcd) {
                 err = -ENOMEM;
-                goto disable_xusbc;
+                goto put_powerdomains;
         }
 
         /*
@@ -1222,12 +1284,13 @@ put_rpm:
 disable_rpm:
         pm_runtime_disable(&pdev->dev);
         usb_put_hcd(tegra->hcd);
-disable_xusbc:
-        if (!pdev->dev.pm_domain)
+put_powerdomains:
+        if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
                 tegra_powergate_power_off(TEGRA_POWERGATE_XUSBC);
-disable_xusba:
-        if (!pdev->dev.pm_domain)
                 tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
+        } else {
+                tegra_xusb_powerdomain_remove(&pdev->dev, tegra);
+        }
 put_padctl:
         tegra_xusb_padctl_put(tegra->padctl);
         return err;
@@ -1249,9 +1312,11 @@ static int tegra_xusb_remove(struct platform_device *pdev)
         pm_runtime_put_sync(&pdev->dev);
         pm_runtime_disable(&pdev->dev);
 
-        if (!pdev->dev.pm_domain) {
+        if (!of_property_read_bool(pdev->dev.of_node, "power-domains")) {
                 tegra_powergate_power_off(TEGRA_POWERGATE_XUSBC);
                 tegra_powergate_power_off(TEGRA_POWERGATE_XUSBA);
+        } else {
+                tegra_xusb_powerdomain_remove(&pdev->dev, tegra);
         }
 
         tegra_xusb_padctl_put(tegra->padctl);