It is possible that the usb power_supply is registered after the probe of dwc3. In this case, trying to get the usb power_supply during the probe will fail and there is no chance to try again. Also the usb power_supply might be unregistered at anytime so that the handle of it in dwc3 would become invalid. To fix this, get the handle right before calling to power_supply functions and put it afterward. dwc3_gadet_vbus_draw might be in interrupt context. Create a kthread worker beforehand and use it to process the "might-sleep" power_supply_put ASAP after the property set. Fixes: 6f0764b5adea ("usb: dwc3: add a power supply for current control") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Kyle Tso <kyletso@xxxxxxxxxx> --- v2 -> v3: - Only move power_supply_put to a work. Still call _get_by_name and _set_property in dwc3_gadget_vbus_draw. - Create a kthread_worker to handle the work v1 -> v2: - move power_supply_put out of interrupt context drivers/usb/dwc3/core.c | 29 ++++++++++++---------------- drivers/usb/dwc3/core.h | 6 ++++-- drivers/usb/dwc3/gadget.c | 40 +++++++++++++++++++++++++++++++++++---- 3 files changed, 52 insertions(+), 23 deletions(-) diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 734de2a8bd21..82c8376330d7 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -1631,8 +1631,6 @@ static void dwc3_get_properties(struct dwc3 *dwc) u8 tx_thr_num_pkt_prd = 0; u8 tx_max_burst_prd = 0; u8 tx_fifo_resize_max_num; - const char *usb_psy_name; - int ret; /* default to highest possible threshold */ lpm_nyet_threshold = 0xf; @@ -1667,12 +1665,7 @@ static void dwc3_get_properties(struct dwc3 *dwc) dwc->sys_wakeup = device_may_wakeup(dwc->sysdev); - ret = device_property_read_string(dev, "usb-psy-name", &usb_psy_name); - if (ret >= 0) { - dwc->usb_psy = power_supply_get_by_name(usb_psy_name); - if (!dwc->usb_psy) - dev_err(dev, "couldn't get usb power supply\n"); - } + device_property_read_string(dev, "usb-psy-name", &dwc->usb_psy_name); dwc->has_lpm_erratum = device_property_read_bool(dev, "snps,has-lpm-erratum"); @@ -2132,19 +2125,24 @@ static int dwc3_probe(struct platform_device *pdev) dwc3_get_software_properties(dwc); + dwc->worker = kthread_create_worker(0, "dwc3-worker"); + if (IS_ERR(dwc->worker)) + return PTR_ERR(dwc->worker); + sched_set_fifo(dwc->worker->task); + dwc->reset = devm_reset_control_array_get_optional_shared(dev); if (IS_ERR(dwc->reset)) { ret = PTR_ERR(dwc->reset); - goto err_put_psy; + goto err_destroy_worker; } ret = dwc3_get_clocks(dwc); if (ret) - goto err_put_psy; + goto err_destroy_worker; ret = reset_control_deassert(dwc->reset); if (ret) - goto err_put_psy; + goto err_destroy_worker; ret = dwc3_clk_enable(dwc); if (ret) @@ -2245,9 +2243,8 @@ static int dwc3_probe(struct platform_device *pdev) dwc3_clk_disable(dwc); err_assert_reset: reset_control_assert(dwc->reset); -err_put_psy: - if (dwc->usb_psy) - power_supply_put(dwc->usb_psy); +err_destroy_worker: + kthread_destroy_worker(dwc->worker); return ret; } @@ -2258,6 +2255,7 @@ static void dwc3_remove(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); + kthread_destroy_worker(dwc->worker); dwc3_core_exit_mode(dwc); dwc3_debugfs_exit(dwc); @@ -2276,9 +2274,6 @@ static void dwc3_remove(struct platform_device *pdev) pm_runtime_set_suspended(&pdev->dev); dwc3_free_event_buffers(dwc); - - if (dwc->usb_psy) - power_supply_put(dwc->usb_psy); } #ifdef CONFIG_PM diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index 1e561fd8b86e..3fc58204db6e 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -993,6 +993,7 @@ struct dwc3_scratchpad_array { /** * struct dwc3 - representation of our controller * @drd_work: workqueue used for role swapping + * @worker: dedicated kthread worker * @ep0_trb: trb which is used for the ctrl_req * @bounce: address of bounce buffer * @setup_buf: used while precessing STD USB requests @@ -1045,7 +1046,7 @@ struct dwc3_scratchpad_array { * @role_sw: usb_role_switch handle * @role_switch_default_mode: default operation mode of controller while * usb role is USB_ROLE_NONE. - * @usb_psy: pointer to power supply interface. + * @usb_psy_name: name of the usb power supply interface * @usb2_phy: pointer to USB2 PHY * @usb3_phy: pointer to USB3 PHY * @usb2_generic_phy: pointer to array of USB2 PHYs @@ -1163,6 +1164,7 @@ struct dwc3_scratchpad_array { */ struct dwc3 { struct work_struct drd_work; + struct kthread_worker *worker; struct dwc3_trb *ep0_trb; void *bounce; u8 *setup_buf; @@ -1223,7 +1225,7 @@ struct dwc3 { struct usb_role_switch *role_sw; enum usb_dr_mode role_switch_default_mode; - struct power_supply *usb_psy; + const char *usb_psy_name; u32 fladj; u32 ref_clk_per; diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 89fc690fdf34..1ff583281eff 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -30,6 +30,11 @@ #define DWC3_ALIGN_FRAME(d, n) (((d)->frame_number + ((d)->interval * (n))) \ & ~((d)->interval - 1)) +struct dwc3_psy_put { + struct kthread_work work; + struct power_supply *psy; +}; + /** * dwc3_gadget_set_test_mode - enables usb2 test modes * @dwc: pointer to our context structure @@ -3047,22 +3052,49 @@ static void dwc3_gadget_set_ssp_rate(struct usb_gadget *g, spin_unlock_irqrestore(&dwc->lock, flags); } +static void dwc3_gadget_psy_put(struct kthread_work *work) +{ + struct dwc3_psy_put *psy_put = container_of(work, struct dwc3_psy_put, work); + + power_supply_put(psy_put->psy); + kfree(psy_put); +} + static int dwc3_gadget_vbus_draw(struct usb_gadget *g, unsigned int mA) { - struct dwc3 *dwc = gadget_to_dwc(g); + struct dwc3 *dwc = gadget_to_dwc(g); + struct power_supply *usb_psy; union power_supply_propval val = {0}; + struct dwc3_psy_put *psy_put; int ret; if (dwc->usb2_phy) return usb_phy_set_power(dwc->usb2_phy, mA); - if (!dwc->usb_psy) + if (!dwc->usb_psy_name) return -EOPNOTSUPP; + usb_psy = power_supply_get_by_name(dwc->usb_psy_name); + if (!usb_psy) { + dev_err(dwc->dev, "couldn't get usb power supply\n"); + return -ENODEV; + } + val.intval = 1000 * mA; - ret = power_supply_set_property(dwc->usb_psy, POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, &val); + ret = power_supply_set_property(usb_psy, POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, &val); + if (ret < 0) { + dev_err(dwc->dev, "failed to set power supply property\n"); + return ret; + } - return ret; + psy_put = kzalloc(sizeof(*psy_put), GFP_ATOMIC); + if (!psy_put) + return -ENOMEM; + kthread_init_work(&psy_put->work, dwc3_gadget_psy_put); + psy_put->psy = usb_psy; + kthread_queue_work(dwc->worker, &psy_put->work); + + return 0; } /** -- 2.46.0.rc2.264.g509ed76dc8-goog