diff options
author | Samuel Holland <samuel@sholland.org> | 2021-01-03 05:06:35 -0600 |
---|---|---|
committer | Chen-Yu Tsai <wens@csie.org> | 2021-01-06 19:34:06 +0800 |
commit | 4a0dbc12e61823ece7172df953c3333c8f5f9222 (patch) | |
tree | b73d605db58d86e166b3afec3d46e877ab8b37f6 /drivers | |
parent | 843107498f91e57d1d4b22cd8787112726fdaeb4 (diff) | |
download | linux-4a0dbc12e61823ece7172df953c3333c8f5f9222.tar.bz2 |
bus: sunxi-rsb: Implement runtime power management
Gate the clock to save power while the controller is idle.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/bus/sunxi-rsb.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/bus/sunxi-rsb.c b/drivers/bus/sunxi-rsb.c index efd222f36cdc..ba5100dfc413 100644 --- a/drivers/bus/sunxi-rsb.c +++ b/drivers/bus/sunxi-rsb.c @@ -46,6 +46,7 @@ #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/pm.h> +#include <linux/pm_runtime.h> #include <linux/regmap.h> #include <linux/reset.h> #include <linux/slab.h> @@ -337,6 +338,10 @@ static int sunxi_rsb_read(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr, return -EINVAL; } + ret = pm_runtime_resume_and_get(rsb->dev); + if (ret) + return ret; + mutex_lock(&rsb->lock); writel(addr, rsb->regs + RSB_ADDR); @@ -352,6 +357,9 @@ static int sunxi_rsb_read(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr, unlock: mutex_unlock(&rsb->lock); + pm_runtime_mark_last_busy(rsb->dev); + pm_runtime_put_autosuspend(rsb->dev); + return ret; } @@ -379,6 +387,10 @@ static int sunxi_rsb_write(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr, return -EINVAL; } + ret = pm_runtime_resume_and_get(rsb->dev); + if (ret) + return ret; + mutex_lock(&rsb->lock); writel(addr, rsb->regs + RSB_ADDR); @@ -389,6 +401,9 @@ static int sunxi_rsb_write(struct sunxi_rsb *rsb, u8 rtaddr, u8 addr, mutex_unlock(&rsb->lock); + pm_runtime_mark_last_busy(rsb->dev); + pm_runtime_put_autosuspend(rsb->dev); + return ret; } @@ -672,10 +687,29 @@ err_clk_disable: static void sunxi_rsb_hw_exit(struct sunxi_rsb *rsb) { + /* Keep the clock and PM reference counts consistent. */ + if (pm_runtime_status_suspended(rsb->dev)) + pm_runtime_resume(rsb->dev); reset_control_assert(rsb->rstc); clk_disable_unprepare(rsb->clk); } +static int __maybe_unused sunxi_rsb_runtime_suspend(struct device *dev) +{ + struct sunxi_rsb *rsb = dev_get_drvdata(dev); + + clk_disable_unprepare(rsb->clk); + + return 0; +} + +static int __maybe_unused sunxi_rsb_runtime_resume(struct device *dev) +{ + struct sunxi_rsb *rsb = dev_get_drvdata(dev); + + return clk_prepare_enable(rsb->clk); +} + static int __maybe_unused sunxi_rsb_suspend(struct device *dev) { struct sunxi_rsb *rsb = dev_get_drvdata(dev); @@ -758,6 +792,12 @@ static int sunxi_rsb_probe(struct platform_device *pdev) if (ret) dev_warn(dev, "Initialize device mode failed: %d\n", ret); + pm_suspend_ignore_children(dev, true); + pm_runtime_set_active(dev); + pm_runtime_set_autosuspend_delay(dev, MSEC_PER_SEC); + pm_runtime_use_autosuspend(dev); + pm_runtime_enable(dev); + of_rsb_register_devices(rsb); return 0; @@ -768,6 +808,7 @@ static int sunxi_rsb_remove(struct platform_device *pdev) struct sunxi_rsb *rsb = platform_get_drvdata(pdev); device_for_each_child(rsb->dev, NULL, sunxi_rsb_remove_devices); + pm_runtime_disable(&pdev->dev); sunxi_rsb_hw_exit(rsb); return 0; @@ -777,10 +818,13 @@ static void sunxi_rsb_shutdown(struct platform_device *pdev) { struct sunxi_rsb *rsb = platform_get_drvdata(pdev); + pm_runtime_disable(&pdev->dev); sunxi_rsb_hw_exit(rsb); } static const struct dev_pm_ops sunxi_rsb_dev_pm_ops = { + SET_RUNTIME_PM_OPS(sunxi_rsb_runtime_suspend, + sunxi_rsb_runtime_resume, NULL) SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(sunxi_rsb_suspend, sunxi_rsb_resume) }; |