On 7/12/2023 11:52 PM, Bhupesh Sharma wrote:
Hi Souradeep,
On Wed, 12 Jul 2023 at 13:58, Souradeep Chowdhury
<quic_schowdhu@xxxxxxxxxxx> 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@xxxxxxxxxxx>
---
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
