On 04/24/2015 03:33 PM, Ulf Hansson wrote:
On 23 April 2015 at 10:45, Rajendra Nayak <rnayak@xxxxxxxxxxxxxx> wrote:Add runtime PM support to handle (core and iface) clocks for devices without a controllable power domain. Once the drivers for these devices are converted to use runtime PM apis, all clock handling (for core and iface) from these drivers can then be removed. Signed-off-by: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx> --- drivers/clk/qcom/gdsc.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/clk/qcom/gdsc.c b/drivers/clk/qcom/gdsc.c index 480ebf6..92b0f6d 100644 --- a/drivers/clk/qcom/gdsc.c +++ b/drivers/clk/qcom/gdsc.c @@ -15,6 +15,7 @@ #include <linux/err.h> #include <linux/jiffies.h> #include <linux/pm_clock.h> +#include <linux/platform_device.h> #include <linux/slab.h> #include "gdsc.h" @@ -226,3 +227,22 @@ void gdsc_unregister(struct device *dev) { of_genpd_del_provider(dev->of_node); } + +static struct dev_pm_domain default_qcom_pm_domain = { + .ops = { + USE_PM_CLK_RUNTIME_OPS + USE_PLATFORM_PM_SLEEP_OPS + }, +}; + +static struct pm_clk_notifier_block qcom_pm_notifier = { + .pm_domain = &default_qcom_pm_domain, + .con_ids = { "core", "iface" }, +}; + +static int __init qcom_pm_runtime_init(void) +{ + pm_clk_add_notifier(&platform_bus_type, &qcom_pm_notifier); + return 0; +} +core_initcall(qcom_pm_runtime_init);First, I don't follow how this code is related to GDSC.
Actually its not. I should probably move it to a pm_runtime.c someplace in drivers/soc/qcom maybe.
Second, I want to see less users of pm_clk_add_notifier() since it's not the proper/long-term way of how to assign PM domain pointers to a device. Instead that shall be done at device registration point. In your case while parsing the DT nodes and adding devices onto to their buses.
but these are devices which do not really have a controllable power domain, they just have controllable clocks.
Yes, I understand that it will requires quite some work to adopt to this behaviour - but that how it shall be done. Finally, an important note, you don't need to use PM domains for these devices at all and thus you don't need to fix what I propose. Instead you only have to implement the runtime PM callbacks for each driver and manage the clocks from there. That is probably also a easier solution.
But that would mean I repeat the same code in all drivers to do a clk_get/prepare/enable/disable/unprepare of the same "core" and "iface" clocks. I thought we have clock_ops.c just to avoid that (atleast up until we have a better way of doing it) And there are atleast a few architecture which have used it to avoid the duplication across all drivers (omap1/davinci/sh/keystone) -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
