[PATCH v2 2/3] usb: dwc3: qcom: Add multi-pd support

Sandeep Maheswaram
2021-10-25T09:08:16Z

Add multi pd support to set performance state for cx domain
to maintain minimum corner voltage for USB clocks.

Signed-off-by: Sandeep Maheswaram <quic_c_sanm@quicinc.com>
---
v2:
Added error handling and detach function.Used attach_by_id function.

drivers/usb/dwc3/dwc3-qcom.c | 87 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 87 insertions(+)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 9abbd01..efbd34a 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -17,6 +17,7 @@
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
+#include <linux/pm_domain.h>
#include <linux/usb/of.h>
#include <linux/reset.h>
#include <linux/iopoll.h>
@@ -89,6 +90,14 @@ struct dwc3_qcom {
bool pm_suspended;
struct icc_path *icc_path_ddr;
struct icc_path *icc_path_apps;
+
+ /* power domain for cx */
+ struct device *pd_cx;
+ struct device_link *pd_link_cx;
+
+ /* power domain for usb gdsc */
+ struct device *pd_usb_gdsc;
+ struct device_link *pd_link_usb_gdsc;
};

static inline void dwc3_qcom_setbits(void __iomem *base, u32 offset, u32 val)
@@ -521,6 +530,79 @@ static int dwc3_qcom_setup_irq(struct platform_device *pdev)
return 0;
}

+static int dwc3_qcom_attach_pd(struct device *dev)
+{
+ struct dwc3_qcom *qcom = dev_get_drvdata(dev);
+ int ret;
+
+ /* Do nothing when in a single power domain */
+ if (dev->pm_domain)
+ return 0;
+
+ qcom->pd_cx = dev_pm_domain_attach_by_id(dev, 0);
+ if (IS_ERR_OR_NULL(qcom->pd_cx)) {
+ dev_err(dev, "Failed to attach cx pd.\n");
+
+ if (!qcom->pd_cx)
+ return -EINVAL;
+ else
+ return PTR_ERR(qcom->pd_cx);
+ }
+
+ qcom->pd_link_cx = device_link_add(dev, qcom->pd_cx,
+ DL_FLAG_STATELESS |
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_RPM_ACTIVE);
+ if (!qcom->pd_link_cx) {
+ dev_err(dev, "Failed to add device_link to cx pd.\n");
+ ret = -EINVAL;
+ goto detach_cx_pd;
+ }
+
+ qcom->pd_usb_gdsc = dev_pm_domain_attach_by_id(dev, 1);
+ if (IS_ERR_OR_NULL(qcom->pd_usb_gdsc)) {
+ dev_err(dev, "Failed to attach usb gdsc pd.\n");
+ if (!qcom->pd_usb_gdsc)
+ ret = -EINVAL;
+ else
+ ret = PTR_ERR(qcom->pd_usb_gdsc);
+ goto del_cx_link;
+ }
+
+ qcom->pd_link_usb_gdsc = device_link_add(dev, qcom->pd_usb_gdsc,
+ DL_FLAG_STATELESS |
+ DL_FLAG_PM_RUNTIME |
+ DL_FLAG_RPM_ACTIVE);
+ if (!qcom->pd_link_usb_gdsc) {
+ dev_err(dev, "Failed to add device_link to usb gdsc pd.\n");
+ ret = -EINVAL;
+ goto detach_gdsc_pd;
+ }
+
+ return 0;
+
+detach_gdsc_pd:
+ dev_pm_domain_detach(qcom->pd_usb_gdsc, true);
+del_cx_link:
+ device_link_del(qcom->pd_link_cx);
+detach_cx_pd:
+ dev_pm_domain_detach(qcom->pd_cx, true);
+ return ret;
+}
+
+static void dwc3_qcom_detach_pd(struct device *dev)
+{
+ struct dwc3_qcom *qcom = dev_get_drvdata(dev);
+
+ if (dev->pm_domain)
+ return;
+
+ device_link_del(qcom->pd_link_usb_gdsc);
+ dev_pm_domain_detach(qcom->pd_usb_gdsc, true);
+ device_link_del(qcom->pd_link_cx);
+ dev_pm_domain_detach(qcom->pd_cx, true);
+}
+
static int dwc3_qcom_clk_init(struct dwc3_qcom *qcom, int count)
{
struct device *dev = qcom->dev;
@@ -837,6 +919,10 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
if (ret)
goto interconnect_exit;

+ ret = dwc3_qcom_attach_pd(dev);
+ if (ret)
+ goto interconnect_exit;
+
device_init_wakeup(&pdev->dev, 1);
qcom->is_suspended = false;
pm_runtime_set_active(dev);
@@ -878,6 +964,7 @@ static int dwc3_qcom_remove(struct platform_device *pdev)
}
qcom->num_clocks = 0;

+ dwc3_qcom_detach_pd(dev);
dwc3_qcom_interconnect_exit(qcom);
reset_control_assert(qcom->resets);

--
2.7.4