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.

Fixes: 6f0764b5adea ("usb: dwc3: add a power supply for current control") Cc: stable@vger.kernel.org Signed-off-by: Kyle Tso kyletso@google.com --- v1 -> v2: - move power_supply_put out of interrupt context

drivers/usb/dwc3/core.c | 62 ++++++++++++++++++++++++++------------- drivers/usb/dwc3/core.h | 10 +++++-- drivers/usb/dwc3/gadget.c | 10 +------ 3 files changed, 51 insertions(+), 31 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 734de2a8bd21..9978067b7734 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -283,6 +283,38 @@ void dwc3_set_mode(struct dwc3 *dwc, u32 mode) queue_work(system_freezable_wq, &dwc->drd_work); }

+static void __dwc3_set_gadget_vbus_draw(struct work_struct *work) +{ + struct dwc3 *dwc = vbus_work_to_dwc(work); + struct power_supply *usb_psy; + union power_supply_propval val = {}; + int ret; + + 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; + } + + val.intval = 1000 * READ_ONCE(dwc->vbus_draw_ma); + 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"); + + power_supply_put(usb_psy); +} + +int dwc3_set_gadget_vbus_draw(struct dwc3 *dwc, unsigned int mA) +{ + if (!dwc->usb_psy_name) + return -EOPNOTSUPP; + + WRITE_ONCE(dwc->vbus_draw_ma, mA); + queue_work(system_highpri_wq, &dwc->vbus_draw_work); + + return 0; +} + u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type) { struct dwc3 *dwc = dep->dwc; @@ -1631,8 +1663,6 @@ 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 +1697,7 @@ 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"); @@ -2130,21 +2155,22 @@ static int dwc3_probe(struct platform_device *pdev)

dwc3_get_properties(dwc);

+ if (dwc->usb_psy_name) + INIT_WORK(&dwc->vbus_draw_work, __dwc3_set_gadget_vbus_draw); + dwc3_get_software_properties(dwc);

dwc->reset = devm_reset_control_array_get_optional_shared(dev); - if (IS_ERR(dwc->reset)) { - ret = PTR_ERR(dwc->reset); - goto err_put_psy; - } + if (IS_ERR(dwc->reset)) + return PTR_ERR(dwc->reset);

ret = dwc3_get_clocks(dwc); if (ret) - goto err_put_psy; + return ret;

ret = reset_control_deassert(dwc->reset); if (ret) - goto err_put_psy; + return ret;

ret = dwc3_clk_enable(dwc); if (ret) @@ -2245,9 +2271,6 @@ 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);

return ret; } @@ -2258,6 +2281,8 @@ static void dwc3_remove(struct platform_device *pdev)

pm_runtime_get_sync(&pdev->dev);

+ if (dwc->usb_psy_name) + cancel_work_sync(&dwc->vbus_draw_work); dwc3_core_exit_mode(dwc); dwc3_debugfs_exit(dwc);

@@ -2276,9 +2301,6 @@ 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..b82eed4ad2b2 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -993,6 +993,8 @@ struct dwc3_scratchpad_array { /** * struct dwc3 - representation of our controller * @drd_work: workqueue used for role swapping + * @vbus_draw_work: work used for setting Vbus current through power_supply + * @vbus_draw_ma: Vbus current draw to be set * @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 +1047,7 @@ 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 +1165,8 @@ struct dwc3_scratchpad_array { */ struct dwc3 { struct work_struct drd_work; + struct work_struct vbus_draw_work; + unsigned int vbus_draw_ma; struct dwc3_trb *ep0_trb; void *bounce; u8 *setup_buf; @@ -1223,7 +1227,7 @@ 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; @@ -1394,6 +1398,7 @@ struct dwc3 { #define INCRX_UNDEF_LENGTH_BURST_MODE 1

#define work_to_dwc(w) (container_of((w), struct dwc3, drd_work)) +#define vbus_work_to_dwc(w) container_of((w), struct dwc3, vbus_draw_work)

/* -------------------------------------------------------------------------- */

@@ -1554,6 +1559,7 @@ struct dwc3_gadget_ep_cmd_params { /* prototypes */ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode); void dwc3_set_mode(struct dwc3 *dwc, u32 mode); +int dwc3_set_gadget_vbus_draw(struct dwc3 *dwc, unsigned int mA); u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type);

#define DWC3_IP_IS(_ip) \ diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 89fc690fdf34..93bf348c24eb 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -3050,19 +3050,11 @@ static void dwc3_gadget_set_ssp_rate(struct usb_gadget *g, static int dwc3_gadget_vbus_draw(struct usb_gadget *g, unsigned int mA) { struct dwc3 *dwc = gadget_to_dwc(g); - union power_supply_propval val = {0}; - int ret;

if (dwc->usb2_phy) return usb_phy_set_power(dwc->usb2_phy, mA);

- if (!dwc->usb_psy) - return -EOPNOTSUPP; - - val.intval = 1000 * mA; - ret = power_supply_set_property(dwc->usb_psy, POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT, &val); - - return ret; + return dwc3_set_gadget_vbus_draw(dwc, mA); }

/**