| Message ID | 18212c7abbb8c833cc07f8500d4905b79c49ec59.1689148711.git.quic_schowdhu@quicinc.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Add notifier call chain to Embedded USB Debug(EUD) driver | expand |
Hi Souradeep, On Wed, 12 Jul 2023 at 13:58, Souradeep Chowdhury <quic_schowdhu@quicinc.com> wrote: > > Add the notifier call chain to EUD driver. The notifier call chain > is added to check the role-switch status of EUD. When multiple > modules are switching roles on the same port, they need to call this > notifier to check the role-switch status of EUD. If EUD is disabled, > then the modules can go for the role-switch, otherwise it needs to > be blocked. The notifier chain can be used to link multiple modules > switching roles on the same port and create a ordering, priority and > conflict resolution among them. The wrapper functions are defined here > which can be used to register a notifier block to the chain, deregister > it and also call the chain. > > Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> > --- > drivers/usb/misc/qcom_eud.c | 52 +++++++++++++++++++++++++++++++++++-- > 1 file changed, 50 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c > index 7f371ea1248c..e6c97a2cf2df 100644 > --- a/drivers/usb/misc/qcom_eud.c > +++ b/drivers/usb/misc/qcom_eud.c > @@ -11,10 +11,13 @@ > #include <linux/kernel.h> > #include <linux/module.h> > #include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_platform.h> > #include <linux/platform_device.h> > #include <linux/slab.h> > #include <linux/sysfs.h> > #include <linux/usb/role.h> > +#include "qcom_eud_notifier.h" > > #define EUD_REG_INT1_EN_MASK 0x0024 > #define EUD_REG_INT_STATUS_1 0x0044 > @@ -22,14 +25,16 @@ > #define EUD_REG_VBUS_INT_CLR 0x0080 > #define EUD_REG_CSR_EUD_EN 0x1014 > #define EUD_REG_SW_ATTACH_DET 0x1018 > -#define EUD_REG_EUD_EN2 0x0000 > +#define EUD_REG_EUD_EN2 0x0000 > > #define EUD_ENABLE BIT(0) > -#define EUD_INT_PET_EUD BIT(0) These indentation issues are already addressed in my EUD patches. Please rebase your patches on the same to reuse those. > +#define EUD_INT_PET_EUD BIT(0) > #define EUD_INT_VBUS BIT(2) > #define EUD_INT_SAFE_MODE BIT(4) > #define EUD_INT_ALL (EUD_INT_VBUS | EUD_INT_SAFE_MODE) > > +static RAW_NOTIFIER_HEAD(eud_nh); > + > struct eud_chip { > struct device *dev; > struct usb_role_switch *role_sw; > @@ -41,6 +46,42 @@ struct eud_chip { > bool usb_attached; > }; > > +int eud_register_notify(struct notifier_block *nb) > +{ > + return raw_notifier_chain_register(&eud_nh, nb); > +} > +EXPORT_SYMBOL_GPL(eud_register_notify); > + > +void eud_unregister_notify(struct notifier_block *nb) > +{ > + raw_notifier_chain_unregister(&eud_nh, nb); > +} > +EXPORT_SYMBOL_GPL(eud_unregister_notify); > + > +void eud_notifier_call_chain(unsigned long role_switch_state) > +{ > + raw_notifier_call_chain(&eud_nh, role_switch_state, NULL); > +} > +EXPORT_SYMBOL_GPL(eud_notifier_call_chain); Probably I missed it, but you have not provided any example users of these APIs in the patchset or reference to another one which shows how these APIs are used. > +static int eud_vbus_spoof_attach_detach(struct notifier_block *nb, unsigned long event, > + void *data) > +{ > + struct device_node *eud = of_find_compatible_node(NULL, NULL, "qcom,eud"); > + struct device *eud_device = bus_find_device_by_of_node(&platform_bus_type, eud); > + struct eud_chip *eud_data = dev_get_drvdata(eud_device); > + > + if (eud_data->enabled && event != USB_ROLE_DEVICE) > + return NOTIFY_BAD; > + else > + return NOTIFY_OK; > +} > + > +static struct notifier_block eud_notifier = { > + .notifier_call = eud_vbus_spoof_attach_detach, > + .priority = 1, Why do you need a 'priority = 1' here, it can be 0 or even lower? Thanks, Bhupesh > +}; > + > static int enable_eud(struct eud_chip *priv) > { > writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN); > @@ -196,6 +237,10 @@ static int eud_probe(struct platform_device *pdev) > return dev_err_probe(chip->dev, ret, > "failed to add role switch release action\n"); > > + ret = eud_register_notify(&eud_notifier); > + if (ret) > + return dev_err_probe(chip->dev, ret, "failed to register notifier\n"); > + > chip->base = devm_platform_ioremap_resource(pdev, 0); > if (IS_ERR(chip->base)) > return PTR_ERR(chip->base); > @@ -226,6 +271,9 @@ static void eud_remove(struct platform_device *pdev) > > device_init_wakeup(&pdev->dev, false); > disable_irq_wake(chip->irq); > + eud_unregister_notify(&eud_notifier); > + > + return 0; > } > > static const struct of_device_id eud_dt_match[] = { > -- > 2.17.1 >
On 7/12/2023 11:52 PM, Bhupesh Sharma wrote: > Hi Souradeep, > > On Wed, 12 Jul 2023 at 13:58, Souradeep Chowdhury > <quic_schowdhu@quicinc.com> wrote: >> >> Add the notifier call chain to EUD driver. The notifier call chain >> is added to check the role-switch status of EUD. When multiple >> modules are switching roles on the same port, they need to call this >> notifier to check the role-switch status of EUD. If EUD is disabled, >> then the modules can go for the role-switch, otherwise it needs to >> be blocked. The notifier chain can be used to link multiple modules >> switching roles on the same port and create a ordering, priority and >> conflict resolution among them. The wrapper functions are defined here >> which can be used to register a notifier block to the chain, deregister >> it and also call the chain. >> >> Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> >> --- >> drivers/usb/misc/qcom_eud.c | 52 +++++++++++++++++++++++++++++++++++-- >> 1 file changed, 50 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c >> index 7f371ea1248c..e6c97a2cf2df 100644 >> --- a/drivers/usb/misc/qcom_eud.c >> +++ b/drivers/usb/misc/qcom_eud.c >> @@ -11,10 +11,13 @@ >> #include <linux/kernel.h> >> #include <linux/module.h> >> #include <linux/of.h> >> +#include <linux/of_address.h> >> +#include <linux/of_platform.h> >> #include <linux/platform_device.h> >> #include <linux/slab.h> >> #include <linux/sysfs.h> >> #include <linux/usb/role.h> >> +#include "qcom_eud_notifier.h" >> >> #define EUD_REG_INT1_EN_MASK 0x0024 >> #define EUD_REG_INT_STATUS_1 0x0044 >> @@ -22,14 +25,16 @@ >> #define EUD_REG_VBUS_INT_CLR 0x0080 >> #define EUD_REG_CSR_EUD_EN 0x1014 >> #define EUD_REG_SW_ATTACH_DET 0x1018 >> -#define EUD_REG_EUD_EN2 0x0000 >> +#define EUD_REG_EUD_EN2 0x0000 >> >> #define EUD_ENABLE BIT(0) >> -#define EUD_INT_PET_EUD BIT(0) > > These indentation issues are already addressed in my EUD patches. > Please rebase your patches on the same to reuse those Ack > >> +#define EUD_INT_PET_EUD BIT(0) >> #define EUD_INT_VBUS BIT(2) >> #define EUD_INT_SAFE_MODE BIT(4) >> #define EUD_INT_ALL (EUD_INT_VBUS | EUD_INT_SAFE_MODE) >> >> +static RAW_NOTIFIER_HEAD(eud_nh); >> + >> struct eud_chip { >> struct device *dev; >> struct usb_role_switch *role_sw; >> @@ -41,6 +46,42 @@ struct eud_chip { >> bool usb_attached; >> }; >> >> +int eud_register_notify(struct notifier_block *nb) >> +{ >> + return raw_notifier_chain_register(&eud_nh, nb); >> +} >> +EXPORT_SYMBOL_GPL(eud_register_notify); >> + >> +void eud_unregister_notify(struct notifier_block *nb) >> +{ >> + raw_notifier_chain_unregister(&eud_nh, nb); >> +} >> +EXPORT_SYMBOL_GPL(eud_unregister_notify); >> + >> +void eud_notifier_call_chain(unsigned long role_switch_state) >> +{ >> + raw_notifier_call_chain(&eud_nh, role_switch_state, NULL); >> +} >> +EXPORT_SYMBOL_GPL(eud_notifier_call_chain); > > Probably I missed it, but you have not provided any example users of > these APIs in the patchset or reference to another one which shows how > these APIs are used. Ack, the usage for this will be posted in the next version. > >> +static int eud_vbus_spoof_attach_detach(struct notifier_block *nb, unsigned long event, >> + void *data) >> +{ >> + struct device_node *eud = of_find_compatible_node(NULL, NULL, "qcom,eud"); >> + struct device *eud_device = bus_find_device_by_of_node(&platform_bus_type, eud); >> + struct eud_chip *eud_data = dev_get_drvdata(eud_device); >> + >> + if (eud_data->enabled && event != USB_ROLE_DEVICE) >> + return NOTIFY_BAD; >> + else >> + return NOTIFY_OK; >> +} >> + >> +static struct notifier_block eud_notifier = { >> + .notifier_call = eud_vbus_spoof_attach_detach, >> + .priority = 1, > > Why do you need a 'priority = 1' here, it can be 0 or even lower? Priority is 0 by default for a notifier block, since eud notifier needs to be the first to be called in the chain to check the role-switch status, I have kept the priority as 1 here. > > Thanks, > Bhupesh > >> +}; >> + >> static int enable_eud(struct eud_chip *priv) >> { >> writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN); >> @@ -196,6 +237,10 @@ static int eud_probe(struct platform_device *pdev) >> return dev_err_probe(chip->dev, ret, >> "failed to add role switch release action\n"); >> >> + ret = eud_register_notify(&eud_notifier); >> + if (ret) >> + return dev_err_probe(chip->dev, ret, "failed to register notifier\n"); >> + >> chip->base = devm_platform_ioremap_resource(pdev, 0); >> if (IS_ERR(chip->base)) >> return PTR_ERR(chip->base); >> @@ -226,6 +271,9 @@ static void eud_remove(struct platform_device *pdev) >> >> device_init_wakeup(&pdev->dev, false); >> disable_irq_wake(chip->irq); >> + eud_unregister_notify(&eud_notifier); >> + >> + return 0; >> } >> >> static const struct of_device_id eud_dt_match[] = { >> -- >> 2.17.1 >>
diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c index 7f371ea1248c..e6c97a2cf2df 100644 --- a/drivers/usb/misc/qcom_eud.c +++ b/drivers/usb/misc/qcom_eud.c @@ -11,10 +11,13 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/sysfs.h> #include <linux/usb/role.h> +#include "qcom_eud_notifier.h" #define EUD_REG_INT1_EN_MASK 0x0024 #define EUD_REG_INT_STATUS_1 0x0044 @@ -22,14 +25,16 @@ #define EUD_REG_VBUS_INT_CLR 0x0080 #define EUD_REG_CSR_EUD_EN 0x1014 #define EUD_REG_SW_ATTACH_DET 0x1018 -#define EUD_REG_EUD_EN2 0x0000 +#define EUD_REG_EUD_EN2 0x0000 #define EUD_ENABLE BIT(0) -#define EUD_INT_PET_EUD BIT(0) +#define EUD_INT_PET_EUD BIT(0) #define EUD_INT_VBUS BIT(2) #define EUD_INT_SAFE_MODE BIT(4) #define EUD_INT_ALL (EUD_INT_VBUS | EUD_INT_SAFE_MODE) +static RAW_NOTIFIER_HEAD(eud_nh); + struct eud_chip { struct device *dev; struct usb_role_switch *role_sw; @@ -41,6 +46,42 @@ struct eud_chip { bool usb_attached; }; +int eud_register_notify(struct notifier_block *nb) +{ + return raw_notifier_chain_register(&eud_nh, nb); +} +EXPORT_SYMBOL_GPL(eud_register_notify); + +void eud_unregister_notify(struct notifier_block *nb) +{ + raw_notifier_chain_unregister(&eud_nh, nb); +} +EXPORT_SYMBOL_GPL(eud_unregister_notify); + +void eud_notifier_call_chain(unsigned long role_switch_state) +{ + raw_notifier_call_chain(&eud_nh, role_switch_state, NULL); +} +EXPORT_SYMBOL_GPL(eud_notifier_call_chain); + +static int eud_vbus_spoof_attach_detach(struct notifier_block *nb, unsigned long event, + void *data) +{ + struct device_node *eud = of_find_compatible_node(NULL, NULL, "qcom,eud"); + struct device *eud_device = bus_find_device_by_of_node(&platform_bus_type, eud); + struct eud_chip *eud_data = dev_get_drvdata(eud_device); + + if (eud_data->enabled && event != USB_ROLE_DEVICE) + return NOTIFY_BAD; + else + return NOTIFY_OK; +} + +static struct notifier_block eud_notifier = { + .notifier_call = eud_vbus_spoof_attach_detach, + .priority = 1, +}; + static int enable_eud(struct eud_chip *priv) { writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN); @@ -196,6 +237,10 @@ static int eud_probe(struct platform_device *pdev) return dev_err_probe(chip->dev, ret, "failed to add role switch release action\n"); + ret = eud_register_notify(&eud_notifier); + if (ret) + return dev_err_probe(chip->dev, ret, "failed to register notifier\n"); + chip->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(chip->base)) return PTR_ERR(chip->base); @@ -226,6 +271,9 @@ static void eud_remove(struct platform_device *pdev) device_init_wakeup(&pdev->dev, false); disable_irq_wake(chip->irq); + eud_unregister_notify(&eud_notifier); + + return 0; } static const struct of_device_id eud_dt_match[] = {
Add the notifier call chain to EUD driver. The notifier call chain is added to check the role-switch status of EUD. When multiple modules are switching roles on the same port, they need to call this notifier to check the role-switch status of EUD. If EUD is disabled, then the modules can go for the role-switch, otherwise it needs to be blocked. The notifier chain can be used to link multiple modules switching roles on the same port and create a ordering, priority and conflict resolution among them. The wrapper functions are defined here which can be used to register a notifier block to the chain, deregister it and also call the chain. Signed-off-by: Souradeep Chowdhury <quic_schowdhu@quicinc.com> --- drivers/usb/misc/qcom_eud.c | 52 +++++++++++++++++++++++++++++++++++-- 1 file changed, 50 insertions(+), 2 deletions(-)