EHCI: HSIC: Perform msm_bus voting update in workqueue context
It is observed that sometimes msm_bus voting upate API taking
longer time to return which delays the HSIC resume sequence
which is time critical.
CRs-Fixed: 388430
Change-Id: I5ad93ee4bbea2b83dad8cc5c8ece8b72ee433d9f
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>
diff --git a/drivers/usb/host/ehci-msm-hsic.c b/drivers/usb/host/ehci-msm-hsic.c
index 4dd6d68..465e512 100644
--- a/drivers/usb/host/ehci-msm-hsic.c
+++ b/drivers/usb/host/ehci-msm-hsic.c
@@ -47,6 +47,8 @@
#define USB_REG_START_OFFSET 0x90
#define USB_REG_END_OFFSET 0x250
+static struct workqueue_struct *ehci_wq;
+
struct msm_hsic_hcd {
struct ehci_hcd ehci;
struct device *dev;
@@ -66,6 +68,9 @@
uint32_t bus_perf_client;
uint32_t wakeup_int_cnt;
enum usb_vdd_type vdd_type;
+
+ struct work_struct bus_vote_w;
+ bool bus_vote;
};
struct msm_hsic_hcd *__mehci;
@@ -658,11 +663,8 @@
dev_err(mehci->dev, "unable to set vddcx voltage for VDD MIN\n");
if (mehci->bus_perf_client && debug_bus_voting_enabled) {
- ret = msm_bus_scale_client_update_request(
- mehci->bus_perf_client, 0);
- if (ret)
- dev_err(mehci->dev, "%s: Failed to dvote for "
- "bus bandwidth %d\n", __func__, ret);
+ mehci->bus_vote = false;
+ queue_work(ehci_wq, &mehci->bus_vote_w);
}
atomic_set(&mehci->in_lpm, 1);
@@ -697,11 +699,8 @@
}
if (mehci->bus_perf_client && debug_bus_voting_enabled) {
- ret = msm_bus_scale_client_update_request(
- mehci->bus_perf_client, 1);
- if (ret)
- dev_err(mehci->dev, "%s: Failed to vote for "
- "bus bandwidth %d\n", __func__, ret);
+ mehci->bus_vote = true;
+ queue_work(ehci_wq, &mehci->bus_vote_w);
}
min_vol = vdd_val[mehci->vdd_type][VDD_MIN];
@@ -769,6 +768,19 @@
}
#endif
+static void ehci_hsic_bus_vote_w(struct work_struct *w)
+{
+ struct msm_hsic_hcd *mehci =
+ container_of(w, struct msm_hsic_hcd, bus_vote_w);
+ int ret;
+
+ ret = msm_bus_scale_client_update_request(mehci->bus_perf_client,
+ mehci->bus_vote);
+ if (ret)
+ dev_err(mehci->dev, "%s: Failed to vote for bus bandwidth %d\n",
+ __func__, ret);
+}
+
static irqreturn_t msm_hsic_irq(struct usb_hcd *hcd)
{
struct msm_hsic_hcd *mehci = hcd_to_hsic(hcd);
@@ -1294,6 +1306,15 @@
goto deinit_vddcx;
}
+ ehci_wq = create_singlethread_workqueue("ehci_wq");
+ if (!ehci_wq) {
+ dev_err(&pdev->dev, "unable to create workqueue\n");
+ ret = -ENOMEM;
+ goto deinit_vddcx;
+ }
+
+ INIT_WORK(&mehci->bus_vote_w, ehci_hsic_bus_vote_w);
+
ret = usb_add_hcd(hcd, hcd->irq, IRQF_SHARED);
if (ret) {
dev_err(&pdev->dev, "unable to register HCD\n");
@@ -1339,11 +1360,8 @@
msm_bus_scale_register_client(pdata->bus_scale_table);
/* Configure BUS performance parameters for MAX bandwidth */
if (mehci->bus_perf_client) {
- ret = msm_bus_scale_client_update_request(
- mehci->bus_perf_client, 1);
- if (ret)
- dev_err(&pdev->dev, "%s: Failed to vote for "
- "bus bandwidth %d\n", __func__, ret);
+ mehci->bus_vote = true;
+ queue_work(ehci_wq, &mehci->bus_vote_w);
} else {
dev_err(&pdev->dev, "%s: Failed to register BUS "
"scaling client!!\n", __func__);
@@ -1369,6 +1387,7 @@
return 0;
unconfig_gpio:
+ destroy_workqueue(ehci_wq);
msm_hsic_config_gpios(mehci, 0);
deinit_vddcx:
msm_hsic_init_vddcx(mehci, 0);
@@ -1396,6 +1415,14 @@
free_irq(mehci->wakeup_irq, mehci);
}
+ /*
+ * If the update request is called after unregister, the request will
+ * fail. Results are undefined if unregister is called in the middle of
+ * update request.
+ */
+ mehci->bus_vote = false;
+ cancel_work_sync(&mehci->bus_vote_w);
+
if (mehci->bus_perf_client)
msm_bus_scale_unregister_client(mehci->bus_perf_client);
@@ -1403,6 +1430,8 @@
device_init_wakeup(&pdev->dev, 0);
pm_runtime_set_suspended(&pdev->dev);
+ destroy_workqueue(ehci_wq);
+
usb_remove_hcd(hcd);
msm_hsic_config_gpios(mehci, 0);
msm_hsic_init_vddcx(mehci, 0);