[PATCH net-next v2 5/7] net: ipa: use device_init_wakeup()

Alex Elder
2020-09-12T00:47:25Z

The call to wakeup_source_register() in ipa_probe() does not do what
it was intended to do. Call device_init_wakeup() in ipa_setup()
instead, to set the IPA device as wakeup-capable and to initially
enable wakeup capability.

When we receive a SUSPEND interrupt, call pm_wakeup_dev_event()
with a zero processing time, to simply call for a resume without
any other processing. The ipa_resume() call will take care of
waking things up again, and will handle receiving the packet.

Signed-off-by: Alex Elder <elder@linaro.org>
---
drivers/net/ipa/ipa.h | 2 --
drivers/net/ipa/ipa_main.c | 43 ++++++++++++++++----------------------
2 files changed, 18 insertions(+), 27 deletions(-)

diff --git a/drivers/net/ipa/ipa.h b/drivers/net/ipa/ipa.h
index e02fe979b645b..c688155ccf375 100644
--- a/drivers/net/ipa/ipa.h
+++ b/drivers/net/ipa/ipa.h
@@ -114,8 +114,6 @@ struct ipa {
void *zero_virt;
size_t zero_size;

- struct wakeup_source *wakeup_source;
-
/* Bit masks indicating endpoint state */
u32 available; /* supported by hardware */
u32 filter_map;
diff --git a/drivers/net/ipa/ipa_main.c b/drivers/net/ipa/ipa_main.c
index 3b68b53c99015..5e714d9d2e5cb 100644
--- a/drivers/net/ipa/ipa_main.c
+++ b/drivers/net/ipa/ipa_main.c
@@ -75,18 +75,19 @@
* @ipa: IPA pointer
* @irq_id: IPA interrupt type (unused)
*
- * When in suspended state, the IPA can trigger a resume by sending a SUSPEND
- * IPA interrupt.
+ * If an RX endpoint is in suspend state, and the IPA has a packet
+ * destined for that endpoint, the IPA generates a SUSPEND interrupt
+ * to inform the AP that it should resume the endpoint. If we get
+ * one of these interrupts we just resume everything.
*/
static void ipa_suspend_handler(struct ipa *ipa, enum ipa_irq_id irq_id)
{
- /* Take a a single clock reference to prevent suspend. All
- * endpoints will be resumed as a result. This reference will
- * be dropped when we get a power management suspend request.
- * The first call activates the clock; ignore any others.
+ /* Just report the event, and let system resume handle the rest.
+ * More than one endpoint could signal this; if so, ignore
+ * all but the first.
*/
if (!test_and_set_bit(IPA_FLAG_CLOCK_HELD, ipa->flags))
- ipa_clock_get(ipa);
+ pm_wakeup_dev_event(&ipa->pdev->dev, 0, true);

/* Acknowledge/clear the suspend interrupt on all endpoints */
ipa_interrupt_suspend_clear_all(ipa->interrupt);
@@ -107,6 +108,7 @@ int ipa_setup(struct ipa *ipa)
{
struct ipa_endpoint *exception_endpoint;
struct ipa_endpoint *command_endpoint;
+ struct device *dev = &ipa->pdev->dev;
int ret;

/* Setup for IPA v3.5.1 has some slight differences */
@@ -124,6 +126,10 @@ int ipa_setup(struct ipa *ipa)

ipa_uc_setup(ipa);

+ ret = device_init_wakeup(dev, true);
+ if (ret)
+ goto err_uc_teardown;
+
ipa_endpoint_setup(ipa);

/* We need to use the AP command TX endpoint to perform other
@@ -159,7 +165,7 @@ int ipa_setup(struct ipa *ipa)

ipa->setup_complete = true;

- dev_info(&ipa->pdev->dev, "IPA driver setup completed successfully\n");
+ dev_info(dev, "IPA driver setup completed successfully\n");

return 0;

@@ -174,6 +180,8 @@ int ipa_setup(struct ipa *ipa)
ipa_endpoint_disable_one(command_endpoint);
err_endpoint_teardown:
ipa_endpoint_teardown(ipa);
+ (void)device_init_wakeup(dev, false);
+err_uc_teardown:
ipa_uc_teardown(ipa);
ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);
ipa_interrupt_teardown(ipa->interrupt);
@@ -201,6 +209,7 @@ static void ipa_teardown(struct ipa *ipa)
command_endpoint = ipa->name_map[IPA_ENDPOINT_AP_COMMAND_TX];
ipa_endpoint_disable_one(command_endpoint);
ipa_endpoint_teardown(ipa);
+ (void)device_init_wakeup(&ipa->pdev->dev, false);
ipa_uc_teardown(ipa);
ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);
ipa_interrupt_teardown(ipa->interrupt);
@@ -715,7 +724,6 @@ static void ipa_validate_build(void)
*/
static int ipa_probe(struct platform_device *pdev)
{
- struct wakeup_source *wakeup_source;
struct device *dev = &pdev->dev;
const struct ipa_data *data;
struct ipa_clock *clock;
@@ -764,19 +772,11 @@ static int ipa_probe(struct platform_device *pdev)
goto err_clock_exit;
}

- /* Create a wakeup source. */
- wakeup_source = wakeup_source_register(dev, "ipa");
- if (!wakeup_source) {
- /* The most likely reason for failure is memory exhaustion */
- ret = -ENOMEM;
- goto err_clock_exit;
- }
-
/* Allocate and initialize the IPA structure */
ipa = kzalloc(sizeof(*ipa), GFP_KERNEL);
if (!ipa) {
ret = -ENOMEM;
- goto err_wakeup_source_unregister;
+ goto err_clock_exit;
}

ipa->pdev = pdev;
@@ -784,7 +784,6 @@ static int ipa_probe(struct platform_device *pdev)
ipa->modem_rproc = rproc;
ipa->clock = clock;
__clear_bit(IPA_FLAG_CLOCK_HELD, ipa->flags);
- ipa->wakeup_source = wakeup_source;
ipa->version = data->version;

ret = ipa_reg_init(ipa);
@@ -863,8 +862,6 @@ static int ipa_probe(struct platform_device *pdev)
ipa_reg_exit(ipa);
err_kfree_ipa:
kfree(ipa);
-err_wakeup_source_unregister:
- wakeup_source_unregister(wakeup_source);
err_clock_exit:
ipa_clock_exit(clock);
err_rproc_put:
@@ -878,11 +875,8 @@ static int ipa_remove(struct platform_device *pdev)
struct ipa *ipa = dev_get_drvdata(&pdev->dev);
struct rproc *rproc = ipa->modem_rproc;
struct ipa_clock *clock = ipa->clock;
- struct wakeup_source *wakeup_source;
int ret;

- wakeup_source = ipa->wakeup_source;
-
if (ipa->setup_complete) {
ret = ipa_modem_stop(ipa);
if (ret)
@@ -899,7 +893,6 @@ static int ipa_remove(struct platform_device *pdev)
ipa_mem_exit(ipa);
ipa_reg_exit(ipa);
kfree(ipa);
- wakeup_source_unregister(wakeup_source);
ipa_clock_exit(clock);
rproc_put(rproc);

--
2.20.1