From 752b5ed5f6998e118626feea7375782c4cf5aad6 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Tue, 4 Aug 2015 14:28:02 +0200 Subject: clk: shmobile: Add CPG/MSTP Clock Domain support Add Clock Domain support to the Clock Pulse Generator (CPG) Module Stop (MSTP) Clocks driver using the generic PM Domain. This allows to power-manage the module clocks of SoC devices that are part of the CPG/MSTP Clock Domain using Runtime PM, or for system suspend/resume. SoC devices that are part of the CPG/MSTP Clock Domain and can be power-managed through an MSTP clock should be tagged in DT with a proper "power-domains" property. The CPG/MSTP Clock Domain code will scan such devices for clocks that are suitable for power-managing the device, by looking for a clock that is compatible with "renesas,cpg-mstp-clocks". Signed-off-by: Geert Uytterhoeven Acked-by: Laurent Pinchart Acked-by: Stephen Boyd Reviewed-by: Ulf Hansson Reviewed-by: Kevin Hilman Signed-off-by: Simon Horman --- drivers/clk/shmobile/clk-mstp.c | 87 +++++++++++++++++++++++++++++++++++++++++ include/linux/clk/shmobile.h | 12 ++++++ 2 files changed, 99 insertions(+) diff --git a/drivers/clk/shmobile/clk-mstp.c b/drivers/clk/shmobile/clk-mstp.c index 2d2fe773ac81..b1df7b2f1e97 100644 --- a/drivers/clk/shmobile/clk-mstp.c +++ b/drivers/clk/shmobile/clk-mstp.c @@ -2,6 +2,7 @@ * R-Car MSTP clocks * * Copyright (C) 2013 Ideas On Board SPRL + * Copyright (C) 2015 Glider bvba * * Contact: Laurent Pinchart * @@ -10,11 +11,16 @@ * the Free Software Foundation; version 2 of the License. */ +#include #include #include +#include +#include #include #include #include +#include +#include #include /* @@ -236,3 +242,84 @@ static void __init cpg_mstp_clocks_init(struct device_node *np) of_clk_add_provider(np, of_clk_src_onecell_get, &group->data); } CLK_OF_DECLARE(cpg_mstp_clks, "renesas,cpg-mstp-clocks", cpg_mstp_clocks_init); + + +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF +int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev) +{ + struct device_node *np = dev->of_node; + struct of_phandle_args clkspec; + struct clk *clk; + int i = 0; + int error; + + while (!of_parse_phandle_with_args(np, "clocks", "#clock-cells", i, + &clkspec)) { + if (of_device_is_compatible(clkspec.np, + "renesas,cpg-mstp-clocks")) + goto found; + + of_node_put(clkspec.np); + i++; + } + + return 0; + +found: + clk = of_clk_get_from_provider(&clkspec); + of_node_put(clkspec.np); + + if (IS_ERR(clk)) + return PTR_ERR(clk); + + error = pm_clk_create(dev); + if (error) { + dev_err(dev, "pm_clk_create failed %d\n", error); + goto fail_put; + } + + error = pm_clk_add_clk(dev, clk); + if (error) { + dev_err(dev, "pm_clk_add_clk %pC failed %d\n", clk, error); + goto fail_destroy; + } + + return 0; + +fail_destroy: + pm_clk_destroy(dev); +fail_put: + clk_put(clk); + return error; +} + +void cpg_mstp_detach_dev(struct generic_pm_domain *domain, struct device *dev) +{ + if (!list_empty(&dev->power.subsys_data->clock_list)) + pm_clk_destroy(dev); +} + +void __init cpg_mstp_add_clk_domain(struct device_node *np) +{ + struct generic_pm_domain *pd; + u32 ncells; + + if (of_property_read_u32(np, "#power-domain-cells", &ncells)) { + pr_warn("%s lacks #power-domain-cells\n", np->full_name); + return; + } + + pd = kzalloc(sizeof(*pd), GFP_KERNEL); + if (!pd) + return; + + pd->name = np->name; + + pd->flags = GENPD_FLAG_PM_CLK; + pm_genpd_init(pd, &simple_qos_governor, false); + pd->attach_dev = cpg_mstp_attach_dev; + pd->detach_dev = cpg_mstp_detach_dev; + + of_genpd_add_provider_simple(np, pd); +} +#endif /* !CONFIG_PM_GENERIC_DOMAINS_OF */ diff --git a/include/linux/clk/shmobile.h b/include/linux/clk/shmobile.h index 63a8159c4e64..cb19cc1865ca 100644 --- a/include/linux/clk/shmobile.h +++ b/include/linux/clk/shmobile.h @@ -16,8 +16,20 @@ #include +struct device; +struct device_node; +struct generic_pm_domain; + void r8a7778_clocks_init(u32 mode); void r8a7779_clocks_init(u32 mode); void rcar_gen2_clocks_init(u32 mode); +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF +void cpg_mstp_add_clk_domain(struct device_node *np); +int cpg_mstp_attach_dev(struct generic_pm_domain *domain, struct device *dev); +void cpg_mstp_detach_dev(struct generic_pm_domain *domain, struct device *dev); +#else +static inline void cpg_mstp_add_clk_domain(struct device_node *np) {} +#endif + #endif -- cgit