diff options
Diffstat (limited to 'drivers/clk/samsung/clk-exynos-clkout.c')
| -rw-r--r-- | drivers/clk/samsung/clk-exynos-clkout.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/clk/samsung/clk-exynos-clkout.c b/drivers/clk/samsung/clk-exynos-clkout.c new file mode 100644 index 000000000..9c95390d2 --- /dev/null +++ b/drivers/clk/samsung/clk-exynos-clkout.c @@ -0,0 +1,162 @@ +/* + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Tomasz Figa <t.figa@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Clock driver for Exynos clock output + */ + +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/syscore_ops.h> + +#define EXYNOS_CLKOUT_NR_CLKS 1 +#define EXYNOS_CLKOUT_PARENTS 32 + +#define EXYNOS_PMU_DEBUG_REG 0xa00 +#define EXYNOS_CLKOUT_DISABLE_SHIFT 0 +#define EXYNOS_CLKOUT_MUX_SHIFT 8 +#define EXYNOS4_CLKOUT_MUX_MASK 0xf +#define EXYNOS5_CLKOUT_MUX_MASK 0x1f + +struct exynos_clkout { + struct clk_gate gate; + struct clk_mux mux; + spinlock_t slock; + void __iomem *reg; + u32 pmu_debug_save; + struct clk_hw_onecell_data data; +}; + +static struct exynos_clkout *clkout; + +static int exynos_clkout_suspend(void) +{ + clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG); + + return 0; +} + +static void exynos_clkout_resume(void) +{ + writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG); +} + +static struct syscore_ops exynos_clkout_syscore_ops = { + .suspend = exynos_clkout_suspend, + .resume = exynos_clkout_resume, +}; + +static void __init exynos_clkout_init(struct device_node *node, u32 mux_mask) +{ + const char *parent_names[EXYNOS_CLKOUT_PARENTS]; + struct clk *parents[EXYNOS_CLKOUT_PARENTS]; + int parent_count; + int ret; + int i; + + clkout = kzalloc(struct_size(clkout, data.hws, EXYNOS_CLKOUT_NR_CLKS), + GFP_KERNEL); + if (!clkout) + return; + + spin_lock_init(&clkout->slock); + + parent_count = 0; + for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) { + char name[] = "clkoutXX"; + + snprintf(name, sizeof(name), "clkout%d", i); + parents[i] = of_clk_get_by_name(node, name); + if (IS_ERR(parents[i])) { + parent_names[i] = "none"; + continue; + } + + parent_names[i] = __clk_get_name(parents[i]); + parent_count = i + 1; + } + + if (!parent_count) + goto free_clkout; + + clkout->reg = of_iomap(node, 0); + if (!clkout->reg) + goto clks_put; + + clkout->gate.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG; + clkout->gate.bit_idx = EXYNOS_CLKOUT_DISABLE_SHIFT; + clkout->gate.flags = CLK_GATE_SET_TO_DISABLE; + clkout->gate.lock = &clkout->slock; + + clkout->mux.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG; + clkout->mux.mask = mux_mask; + clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT; + clkout->mux.lock = &clkout->slock; + + clkout->data.hws[0] = clk_hw_register_composite(NULL, "clkout", + parent_names, parent_count, &clkout->mux.hw, + &clk_mux_ops, NULL, NULL, &clkout->gate.hw, + &clk_gate_ops, CLK_SET_RATE_PARENT + | CLK_SET_RATE_NO_REPARENT); + if (IS_ERR(clkout->data.hws[0])) + goto err_unmap; + + clkout->data.num = EXYNOS_CLKOUT_NR_CLKS; + ret = of_clk_add_hw_provider(node, of_clk_hw_onecell_get, &clkout->data); + if (ret) + goto err_clk_unreg; + + register_syscore_ops(&exynos_clkout_syscore_ops); + + return; + +err_clk_unreg: + clk_hw_unregister(clkout->data.hws[0]); +err_unmap: + iounmap(clkout->reg); +clks_put: + for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) + if (!IS_ERR(parents[i])) + clk_put(parents[i]); +free_clkout: + kfree(clkout); + + pr_err("%s: failed to register clkout clock\n", __func__); +} + +/* + * We use CLK_OF_DECLARE_DRIVER initialization method to avoid setting + * the OF_POPULATED flag on the pmu device tree node, so later the + * Exynos PMU platform device can be properly probed with PMU driver. + */ + +static void __init exynos4_clkout_init(struct device_node *node) +{ + exynos_clkout_init(node, EXYNOS4_CLKOUT_MUX_MASK); +} +CLK_OF_DECLARE_DRIVER(exynos4210_clkout, "samsung,exynos4210-pmu", + exynos4_clkout_init); +CLK_OF_DECLARE_DRIVER(exynos4412_clkout, "samsung,exynos4412-pmu", + exynos4_clkout_init); +CLK_OF_DECLARE_DRIVER(exynos3250_clkout, "samsung,exynos3250-pmu", + exynos4_clkout_init); + +static void __init exynos5_clkout_init(struct device_node *node) +{ + exynos_clkout_init(node, EXYNOS5_CLKOUT_MUX_MASK); +} +CLK_OF_DECLARE_DRIVER(exynos5250_clkout, "samsung,exynos5250-pmu", + exynos5_clkout_init); +CLK_OF_DECLARE_DRIVER(exynos5410_clkout, "samsung,exynos5410-pmu", + exynos5_clkout_init); +CLK_OF_DECLARE_DRIVER(exynos5420_clkout, "samsung,exynos5420-pmu", + exynos5_clkout_init); +CLK_OF_DECLARE_DRIVER(exynos5433_clkout, "samsung,exynos5433-pmu", + exynos5_clkout_init); |