Hi,
to support wakeup from Partial-IO using serial pins of mcu_uart0 and
wkup_uart0, this series adds a new pinctrl state 'wakeup' in which
specific wakeup flags are set on these pins. Partial-IO is a poweroff
state of the SoC in which only a few pingroups are partly powered.
If the user enabled wakeup from the serial port, the pinctrl state is
selected on shutdown. For another deep sleep state, which is comparable
with suspend to memory, the same pinctrl state is selected on suspend as
well.
The series is based on v6.9-rc1.
This series is part of a bigger topic to support Partial-IO on am62,
am62a and am62p. Partial-IO is a poweroff state in which some pins are
able to wakeup the SoC. In detail MCU m_can and two serial port pins can
trigger the wakeup.
These two other series are relevant for the support of Partial-IO:
- firmware: ti_sci: Partial-IO support
- can: m_can: Add am62 wakeup support
A test branch is available that includes all patches required to test
Partial-IO:
https://gitlab.baylibre.com/msp8/linux/-/tree/integration/am62-lp-sk-partialio/v6.9?ref_type=heads
After enabling Wake-on-LAN the system can be powered off and will enter
the Partial-IO state in which it can be woken up by activity on the
specific pins:
ethtool -s can0 wol p
ethtool -s can1 wol p
poweroff
I tested these patches on am62-lp-sk.
Best,
Markus
Markus Schneider-Pargmann (5):
dt-bindings: serial: 8250_omap: Add wakeup pinctrl state
serial: 8250: omap: Remove unused wakeups_enabled
serial: 8250: omap: Set wakeup capable, do not enable
serial: 8250: omap: Support wakeup pinctrl state
serial: 8250: omap: Set wakeup pinctrl on suspend
.../devicetree/bindings/serial/8250_omap.yaml | 16 ++++++
drivers/tty/serial/8250/8250_omap.c | 56 ++++++++++++++++++-
2 files changed, 70 insertions(+), 2 deletions(-)
--
2.43.0
Pins associated with the 8250 omap unit can be the source of a wakeup in
deep sleep states. To be able to wakeup, these pins have to be
configured in a special way. To support this configuration add the
default and wakeup pinctrl states.
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
---
.../devicetree/bindings/serial/8250_omap.yaml | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/Documentation/devicetree/bindings/serial/8250_omap.yaml b/Documentation/devicetree/bindings/serial/8250_omap.yaml
index 6a7be42da523..402e2ca81017 100644
--- a/Documentation/devicetree/bindings/serial/8250_omap.yaml
+++ b/Documentation/devicetree/bindings/serial/8250_omap.yaml
@@ -77,6 +77,22 @@ properties:
current-speed: true
overrun-throttle-ms: true
+ pinctrl-0:
+ description: Default pinctrl state
+
+ pinctrl-1:
+ description: Wakeup pinctrl state
+
+ pinctrl-names:
+ description:
+ When present should contain at least "default" describing the default pin
+ states. The second state called "wakeup" describes the pins in their
+ wakeup configuration required to exit sleep states.
+ minItems: 1
+ items:
+ - const: default
+ - const: wakeup
+
required:
- compatible
- reg
--
2.43.0
This field seems to be unused for quite some time already. Remove it.
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
---
drivers/tty/serial/8250/8250_omap.c | 1 -
1 file changed, 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 66901d93089a..ca456ea23317 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -141,7 +141,6 @@ struct omap8250_priv {
atomic_t active;
bool is_suspending;
int wakeirq;
- int wakeups_enabled;
u32 latency;
u32 calc_latency;
struct pm_qos_request pm_qos_request;
--
2.43.0
The driver sets wakeup enable by default. But not all uarts are meant to
be wakeup enabled. Change the default to be wakeup capable but not
enabled. The user can enable wakeup when needed.
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
---
drivers/tty/serial/8250/8250_omap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index ca456ea23317..5b7508dfb5d8 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -1496,7 +1496,7 @@ static int omap8250_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, priv);
- device_init_wakeup(&pdev->dev, true);
+ device_set_wakeup_capable(&pdev->dev, true);
pm_runtime_enable(&pdev->dev);
pm_runtime_use_autosuspend(&pdev->dev);
--
2.43.0
UART can be used as a wakeup source for am62 from a powered-off SoC
state. To enable wakeup from UART am62 requires a wakeup flag being set
in the pinctrl.
If the device is marked as wakeup enabled, select the 'wakeup' pinctrl
state on sys_off.
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
---
drivers/tty/serial/8250/8250_omap.c | 39 +++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 5b7508dfb5d8..617a421a1396 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -27,8 +27,10 @@
#include <linux/pm_qos.h>
#include <linux/pm_wakeirq.h>
#include <linux/dma-mapping.h>
+#include <linux/reboot.h>
#include <linux/sys_soc.h>
#include <linux/pm_domain.h>
+#include <linux/pinctrl/consumer.h>
#include "8250.h"
@@ -149,6 +151,9 @@ struct omap8250_priv {
spinlock_t rx_dma_lock;
bool rx_dma_broken;
bool throttled;
+
+ struct pinctrl *pinctrl;
+ struct pinctrl_state *pinctrl_wakeup;
};
struct omap8250_dma_params {
@@ -1345,6 +1350,30 @@ static int omap8250_no_handle_irq(struct uart_port *port)
return 0;
}
+static int omap8250_select_wakeup_pinctrl(struct device *dev,
+ struct omap8250_priv *priv)
+{
+ if (IS_ERR_OR_NULL(priv->pinctrl_wakeup))
+ return 0;
+
+ if (!device_may_wakeup(dev))
+ return 0;
+
+ return pinctrl_select_state(priv->pinctrl, priv->pinctrl_wakeup);
+}
+
+static int omap8250_sysoff_handler(struct sys_off_data *data)
+{
+ struct omap8250_priv *priv = dev_get_drvdata(data->dev);
+ int ret;
+
+ ret = omap8250_select_wakeup_pinctrl(data->dev, priv);
+ if (ret)
+ dev_err(data->dev, "Failed to select pinctrl state 'wakeup', continuing poweroff\n");
+
+ return NOTIFY_DONE;
+}
+
static struct omap8250_dma_params am654_dma = {
.rx_size = SZ_2K,
.rx_trigger = 1,
@@ -1566,6 +1595,16 @@ static int omap8250_probe(struct platform_device *pdev)
priv->line = ret;
pm_runtime_mark_last_busy(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
+
+ priv->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (!IS_ERR_OR_NULL(priv->pinctrl))
+ priv->pinctrl_wakeup = pinctrl_lookup_state(priv->pinctrl, "wakeup");
+
+ devm_register_sys_off_handler(&pdev->dev,
+ SYS_OFF_MODE_POWER_OFF_PREPARE,
+ SYS_OFF_PRIO_DEFAULT,
+ omap8250_sysoff_handler, NULL);
+
return 0;
err:
pm_runtime_dont_use_autosuspend(&pdev->dev);
--
2.43.0
To enable the serial driver and it's pin to be a wakeup source in
suspend to ram states, select the wakeup pinctrl state on suspend and
restore the default pinctrl state on resume.
Signed-off-by: Markus Schneider-Pargmann <[email protected]>
---
drivers/tty/serial/8250/8250_omap.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 617a421a1396..61f056c4e78e 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -1663,6 +1663,13 @@ static int omap8250_suspend(struct device *dev)
struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
int err = 0;
+ err = omap8250_select_wakeup_pinctrl(dev, priv);
+ if (err) {
+ dev_err(dev, "Failed to select wakeup pinctrl, aborting suspend %pe\n",
+ ERR_PTR(err));
+ return err;
+ }
+
serial8250_suspend_port(priv->line);
err = pm_runtime_resume_and_get(dev);
@@ -1696,6 +1703,13 @@ static int omap8250_resume(struct device *dev)
struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
int err;
+ err = pinctrl_select_default_state(dev);
+ if (err) {
+ dev_err(dev, "Failed to select default pinctrl state on resume: %pe\n",
+ ERR_PTR(err));
+ return err;
+ }
+
if (uart_console(&up->port) && console_suspend_enabled) {
if (console_suspend_enabled) {
err = pm_runtime_force_resume(dev);
--
2.43.0
Hello Markus,
On Thu, May 23, 2024 at 09:58:14AM +0200, Markus Schneider-Pargmann wrote:
> Hi,
>
> to support wakeup from Partial-IO using serial pins of mcu_uart0 and
> wkup_uart0, this series adds a new pinctrl state 'wakeup' in which
> specific wakeup flags are set on these pins. Partial-IO is a poweroff
> state of the SoC in which only a few pingroups are partly powered.
>
> If the user enabled wakeup from the serial port, the pinctrl state is
> selected on shutdown. For another deep sleep state, which is comparable
> with suspend to memory, the same pinctrl state is selected on suspend as
> well.
>
..
>
> After enabling Wake-on-LAN the system can be powered off and will enter
> the Partial-IO state in which it can be woken up by activity on the
> specific pins:
> ethtool -s can0 wol p
> ethtool -s can1 wol p
> poweroff
Confused ... Why the CAN? This is about the UART.
Francesco
On Thu, May 23, 2024 at 09:58:18AM +0200, Markus Schneider-Pargmann wrote:
> UART can be used as a wakeup source for am62 from a powered-off SoC
> state. To enable wakeup from UART am62 requires a wakeup flag being set
> in the pinctrl.
>
> If the device is marked as wakeup enabled, select the 'wakeup' pinctrl
> state on sys_off.
..
> #include <linux/pm_qos.h>
> #include <linux/pm_wakeirq.h>
> #include <linux/dma-mapping.h>
> +#include <linux/reboot.h>
See below.
> #include <linux/sys_soc.h>
> #include <linux/pm_domain.h>
> +#include <linux/pinctrl/consumer.h>
Can we make some order here and put this before above pm_*.h or even earlier
according to the alphabet?
..
> + priv->pinctrl = devm_pinctrl_get(&pdev->dev);
> + if (!IS_ERR_OR_NULL(priv->pinctrl))
Shouldn't we report an error to the user? I assume that NULL is for optional
pin control, otherwise it's an error state which at bare minimum has to be
reported.
> + priv->pinctrl_wakeup = pinctrl_lookup_state(priv->pinctrl, "wakeup");
> + devm_register_sys_off_handler(&pdev->dev,
No error check?
> + SYS_OFF_MODE_POWER_OFF_PREPARE,
> + SYS_OFF_PRIO_DEFAULT,
> + omap8250_sysoff_handler, NULL);
> +
--
With Best Regards,
Andy Shevchenko
On Thu, May 23, 2024 at 09:58:17AM +0200, Markus Schneider-Pargmann wrote:
> The driver sets wakeup enable by default. But not all uarts are meant to
UARTs
> be wakeup enabled. Change the default to be wakeup capable but not
> enabled. The user can enable wakeup when needed.
--
With Best Regards,
Andy Shevchenko
On Thu, 23 May 2024 09:58:15 +0200, Markus Schneider-Pargmann wrote:
> Pins associated with the 8250 omap unit can be the source of a wakeup in
> deep sleep states. To be able to wakeup, these pins have to be
> configured in a special way. To support this configuration add the
> default and wakeup pinctrl states.
>
> Signed-off-by: Markus Schneider-Pargmann <[email protected]>
> ---
> .../devicetree/bindings/serial/8250_omap.yaml | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
Reviewed-by: Rob Herring (Arm) <[email protected]>