| Message ID | 1442478716-7377-1-git-send-email-zhaoyang.huang@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Thu, Sep 17, 2015 at 04:31:56PM +0800, Zhaoyang Huang wrote: > +struct uart_match { > + struct uart_port *port; > + struct uart_driver *driver; > +}; > + > +static int match_uart_port(struct device *dev, void *data) > +{ > + struct uart_match *match = data; > + > + dev_t devt = MKDEV(match->driver->major, match->driver->minor) + > + match->port->line; > + > + pr_info("the match data of ttyAMA0 is %d %d\n", > + (int)devt, (int)dev->devt); > + > + return dev->devt == devt; /* Actually, only one tty per port */ > +} ... > + ret = pl011_register_port(uap); > + > + if (!of_find_property(dev->dev.of_node, "linux,wakeup", NULL)) { > + uart_dev = NULL; > + return ret; > + } > + > + match.port = &uap->port; > + match.driver = &amba_reg; > + > + uart_dev = device_find_child(&dev->dev, &match, match_uart_port); > + > + if (uart_dev) { > + device_init_wakeup(uart_dev, true); > + dev_pm_set_wake_irq(uart_dev, uap->port.irq); > + } > + > + return ret; I can only describe this code as a hack. This looks like something which should be handled by generic infrastructure at an appropriate point (somewhere inside uart_add_one_port()), not by hacky code in each driver.
On 17/09/15 09:31, Zhaoyang Huang wrote: > the commit use the latest dev_pm_set_wake_irq API instead > of the enable_irq_wake and IRQF_NO_SUSPEND to configure the > ttyAMA device to work as the wakeup source > As I mentioned earlier[1], if this a based on Juno platform, then it gets NACK. Please add this feature when it's needed on a real platform on which hardware supports UART/PL011 as a wake source. Do you have any such platform to test ? On Juno, it can't be used as wakeup source. Regards, Sudeep [1] https://www.marc.info/?l=linux-pm&m=144239396227080&w=2 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 17/09/15 12:01, Zhaoyang Huang wrote: > > > On 17 September 2015 at 18:39, Sudeep Holla <sudeep.holla@arm.com > <mailto:sudeep.holla@arm.com>> wrote: > > > > On 17/09/15 09:31, Zhaoyang Huang wrote: > > the commit use the latest dev_pm_set_wake_irq API instead > of the enable_irq_wake and IRQF_NO_SUSPEND to configure the > ttyAMA device to work as the wakeup source > > > As I mentioned earlier[1], if this a based on Juno platform, then > it gets NACK. Please add this feature when it's needed on a real > platform on which hardware supports UART/PL011 as a wake source. > > Do you have any such platform to test ? On Juno, it can't be used as > wakeup source. > > Regards, > Sudeep > > [1] https://www.marc.info/?l=linux-pm&m=144239396227080&w=2 > > Hi Sudeep, > I think the wakeup source you mean is restricted to the device which can > wake S2R. However, I think the S2I should be also considered, which need > not the hardware support for powering the core up, but just need the isr > to be keep active etc. Hmm, I disagree as we have single control for wakeup and what if you have enabled PL011 as wakeup and S2R is entered assuming there's one active wakeup anyway. IMO w.r.t wakeup source we *must* assume it also wakes up from S2R state always. You didn't answer to my earlier query, why didn't you choose other interrupts like ethernet, gpio or just pick one from the lot of interrupts on Juno as wakeup from S2I. What was the rationale behind your choice especially on Juno ? Just because you can send and receive chars via the tty/console, what if I don't have access to console. We need much better and hardware supported wakeup source like RTC or GPIO. Also a SoC can enter deeper idle states in S2I where UART can't wakeup. How would you know that ? I re-iterate that hardware should have support to ensure it can wakeup the system. Regards, Sudeep -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index fd27e98..1923b94 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -59,6 +59,11 @@ #include <linux/sizes.h> #include <linux/io.h> #include <linux/acpi.h> +#include <linux/suspend.h> +#include <linux/pm_wakeirq.h> +#include <linux/irq.h> + +static struct device *uart_dev; #define UART_NR 14 @@ -2353,11 +2358,29 @@ static int pl011_register_port(struct uart_amba_port *uap) return ret; } +struct uart_match { + struct uart_port *port; + struct uart_driver *driver; +}; + +static int match_uart_port(struct device *dev, void *data) +{ + struct uart_match *match = data; + + dev_t devt = MKDEV(match->driver->major, match->driver->minor) + + match->port->line; + + pr_info("the match data of ttyAMA0 is %d %d\n", + (int)devt, (int)dev->devt); + + return dev->devt == devt; /* Actually, only one tty per port */ +} static int pl011_probe(struct amba_device *dev, const struct amba_id *id) { struct uart_amba_port *uap; struct vendor_data *vendor = id->data; int portnr, ret; + struct uart_match match; portnr = pl011_find_free_port(); if (portnr < 0) @@ -2387,13 +2410,35 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) amba_set_drvdata(dev, uap); - return pl011_register_port(uap); + ret = pl011_register_port(uap); + + if (!of_find_property(dev->dev.of_node, "linux,wakeup", NULL)) { + uart_dev = NULL; + return ret; + } + + match.port = &uap->port; + match.driver = &amba_reg; + + uart_dev = device_find_child(&dev->dev, &match, match_uart_port); + + if (uart_dev) { + device_init_wakeup(uart_dev, true); + dev_pm_set_wake_irq(uart_dev, uap->port.irq); + } + + return ret; } static int pl011_remove(struct amba_device *dev) { struct uart_amba_port *uap = amba_get_drvdata(dev); + if (uart_dev) { + dev_pm_clear_wake_irq(uart_dev); + device_init_wakeup(uart_dev, false); + } + uart_remove_one_port(&amba_reg, &uap->port); pl011_unregister_port(uap); return 0;
the commit use the latest dev_pm_set_wake_irq API instead of the enable_irq_wake and IRQF_NO_SUSPEND to configure the ttyAMA device to work as the wakeup source Signed-off-by: Zhaoyang Huang <zhaoyang.huang@linaro.org> --- drivers/tty/serial/amba-pl011.c | 47 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 46 insertions(+), 1 deletion(-)