Thomas Richard <thomas.richard@xxxxxxxxxxx> writes:
> If the console suspend is disabled, the genpd of the console shall not
> be powered-off during suspend.
> Set the flag GENPD_FLAG_ALWAYS_ON to the corresponding genpd during
> suspend, and restore the original value during the resume.
>
> Signed-off-by: Thomas Richard <thomas.richard@xxxxxxxxxxx>
> ---
> drivers/tty/serial/8250/8250_omap.c | 33 ++++++++++++++++++++++++-----
> 1 file changed, 28 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index ca972fd37725..91a483dc460c 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -27,6 +27,7 @@
> #include <linux/pm_wakeirq.h>
> #include <linux/dma-mapping.h>
> #include <linux/sys_soc.h>
> +#include <linux/pm_domain.h>
>
> #include "8250.h"
>
> @@ -114,6 +115,12 @@
> /* RX FIFO occupancy indicator */
> #define UART_OMAP_RX_LVL 0x19
>
> +/*
> + * Copy of the genpd flags for the console.
> + * Only used if console suspend is disabled
> + */
> +static unsigned int genpd_flags_console;
> +
> struct omap8250_priv {
> void __iomem *membase;
> int line;
> @@ -1617,6 +1624,7 @@ static int omap8250_suspend(struct device *dev)
> {
> struct omap8250_priv *priv = dev_get_drvdata(dev);
> struct uart_8250_port *up = serial8250_get_port(priv->line);
> + struct generic_pm_domain *genpd = pd_to_genpd(dev->pm_domain);
> int err = 0;
>
> serial8250_suspend_port(priv->line);
> @@ -1627,8 +1635,19 @@ static int omap8250_suspend(struct device *dev)
> if (!device_may_wakeup(dev))
> priv->wer = 0;
> serial_out(up, UART_OMAP_WER, priv->wer);
> - if (uart_console(&up->port) && console_suspend_enabled)
> - err = pm_runtime_force_suspend(dev);
> + if (uart_console(&up->port)) {
> + if (console_suspend_enabled)
> + err = pm_runtime_force_suspend(dev);
> + else {
> + /*
> + * The pd shall not be powered-off (no console suspend).
> + * Make copy of genpd flags before to set it always on.
> + * The original value is restored during the resume.
> + */
> + genpd_flags_console = genpd->flags;
> + genpd->flags |= GENPD_FLAG_ALWAYS_ON;
> + }
> + }
This is not the right approach IMO.
Instead, what should be happening is that when `no_console_suspend` is
set, there should be an extra pm_runtime_get() which increases the
device usecount such that the device never runtime suspends, and thus
the domain will not get powered off.
Kevin
