From: Thierry Reding <treding@xxxxxxxxxx> The simple-framebuffer device tree bindings document the power-domains property, so make sure that simplefb supports it. This ensures that the power domains remain enabled as long as simplefb is active. v2: - remove unnecessary call to simplefb_detach_genpds() since that's already done automatically by devres - fix crash if power-domains property is missing in DT Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> --- drivers/video/fbdev/simplefb.c | 93 ++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) diff --git a/drivers/video/fbdev/simplefb.c b/drivers/video/fbdev/simplefb.c index 18025f34fde7..fe682af63827 100644 --- a/drivers/video/fbdev/simplefb.c +++ b/drivers/video/fbdev/simplefb.c @@ -25,6 +25,7 @@ #include <linux/of_clk.h> #include <linux/of_platform.h> #include <linux/parser.h> +#include <linux/pm_domain.h> #include <linux/regulator/consumer.h> static const struct fb_fix_screeninfo simplefb_fix = { @@ -78,6 +79,11 @@ struct simplefb_par { unsigned int clk_count; struct clk **clks; #endif +#if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS + unsigned int num_genpds; + struct device **genpds; + struct device_link **genpd_links; +#endif #if defined CONFIG_OF && defined CONFIG_REGULATOR bool regulators_enabled; u32 regulator_count; @@ -432,6 +438,89 @@ static void simplefb_regulators_enable(struct simplefb_par *par, static void simplefb_regulators_destroy(struct simplefb_par *par) { } #endif +#if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS +static void simplefb_detach_genpds(void *res) +{ + struct simplefb_par *par = res; + unsigned int i = par->num_genpds; + + if (par->num_genpds <= 1) + return; + + while (i--) { + if (par->genpd_links[i]) + device_link_del(par->genpd_links[i]); + + if (!IS_ERR_OR_NULL(par->genpds[i])) + dev_pm_domain_detach(par->genpds[i], true); + } +} + +static int simplefb_attach_genpds(struct simplefb_par *par, + struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + unsigned int i; + int err; + + err = of_count_phandle_with_args(dev->of_node, "power-domains", + "#power-domain-cells"); + if (err < 0) { + dev_info(dev, "failed to parse power-domains: %d\n", err); + return err; + } + + par->num_genpds = err; + + /* + * Single power-domain devices are handled by the driver core, so + * nothing to do here. + */ + if (par->num_genpds <= 1) + return 0; + + par->genpds = devm_kcalloc(dev, par->num_genpds, sizeof(*par->genpds), + GFP_KERNEL); + if (!par->genpds) + return -ENOMEM; + + par->genpd_links = devm_kcalloc(dev, par->num_genpds, + sizeof(*par->genpd_links), + GFP_KERNEL); + if (!par->genpd_links) + return -ENOMEM; + + for (i = 0; i < par->num_genpds; i++) { + par->genpds[i] = dev_pm_domain_attach_by_id(dev, i); + if (IS_ERR(par->genpds[i])) { + err = PTR_ERR(par->genpds[i]); + if (err == -EPROBE_DEFER) { + simplefb_detach_genpds(par); + return err; + } + + dev_warn(dev, "failed to attach domain %u: %d\n", i, err); + continue; + } + + par->genpd_links[i] = device_link_add(dev, par->genpds[i], + DL_FLAG_STATELESS | + DL_FLAG_PM_RUNTIME | + DL_FLAG_RPM_ACTIVE); + if (!par->genpd_links[i]) + dev_warn(dev, "failed to link power-domain %u\n", i); + } + + return devm_add_action_or_reset(dev, simplefb_detach_genpds, par); +} +#else +static int simplefb_attach_genpds(struct simplefb_par *par, + struct platform_device *pdev) +{ + return 0; +} +#endif + static int simplefb_probe(struct platform_device *pdev) { int ret; @@ -518,6 +607,10 @@ static int simplefb_probe(struct platform_device *pdev) if (ret < 0) goto error_clocks; + ret = simplefb_attach_genpds(par, pdev); + if (ret < 0) + goto error_regulators; + simplefb_clocks_enable(par, pdev); simplefb_regulators_enable(par, pdev); -- 2.42.0