|  | /* | 
|  | * WM831x clock control | 
|  | * | 
|  | * Copyright 2011-2 Wolfson Microelectronics PLC. | 
|  | * | 
|  | * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> | 
|  | * | 
|  | *  This program is free software; you can redistribute  it and/or modify it | 
|  | *  under  the terms of  the GNU General  Public License as published by the | 
|  | *  Free Software Foundation;  either version 2 of the  License, or (at your | 
|  | *  option) any later version. | 
|  | * | 
|  | */ | 
|  |  | 
|  | #include <linux/clk.h> | 
|  | #include <linux/clk-provider.h> | 
|  | #include <linux/delay.h> | 
|  | #include <linux/module.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/mfd/wm831x/core.h> | 
|  |  | 
|  | struct wm831x_clk { | 
|  | struct wm831x *wm831x; | 
|  | struct clk_hw xtal_hw; | 
|  | struct clk_hw fll_hw; | 
|  | struct clk_hw clkout_hw; | 
|  | struct clk *xtal; | 
|  | struct clk *fll; | 
|  | struct clk *clkout; | 
|  | bool xtal_ena; | 
|  | }; | 
|  |  | 
|  | static int wm831x_xtal_is_prepared(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | xtal_hw); | 
|  |  | 
|  | return clkdata->xtal_ena; | 
|  | } | 
|  |  | 
|  | static unsigned long wm831x_xtal_recalc_rate(struct clk_hw *hw, | 
|  | unsigned long parent_rate) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | xtal_hw); | 
|  |  | 
|  | if (clkdata->xtal_ena) | 
|  | return 32768; | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static const struct clk_ops wm831x_xtal_ops = { | 
|  | .is_prepared = wm831x_xtal_is_prepared, | 
|  | .recalc_rate = wm831x_xtal_recalc_rate, | 
|  | }; | 
|  |  | 
|  | static struct clk_init_data wm831x_xtal_init = { | 
|  | .name = "xtal", | 
|  | .ops = &wm831x_xtal_ops, | 
|  | .flags = CLK_IS_ROOT, | 
|  | }; | 
|  |  | 
|  | static const unsigned long wm831x_fll_auto_rates[] = { | 
|  | 2048000, | 
|  | 11289600, | 
|  | 12000000, | 
|  | 12288000, | 
|  | 19200000, | 
|  | 22579600, | 
|  | 24000000, | 
|  | 24576000, | 
|  | }; | 
|  |  | 
|  | static int wm831x_fll_is_prepared(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_1); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read FLL_CONTROL_1: %d\n", | 
|  | ret); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | return (ret & WM831X_FLL_ENA) != 0; | 
|  | } | 
|  |  | 
|  | static int wm831x_fll_prepare(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1, | 
|  | WM831X_FLL_ENA, WM831X_FLL_ENA); | 
|  | if (ret != 0) | 
|  | dev_crit(wm831x->dev, "Failed to enable FLL: %d\n", ret); | 
|  |  | 
|  | usleep_range(2000, 2000); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void wm831x_fll_unprepare(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1, WM831X_FLL_ENA, 0); | 
|  | if (ret != 0) | 
|  | dev_crit(wm831x->dev, "Failed to disable FLL: %d\n", ret); | 
|  | } | 
|  |  | 
|  | static unsigned long wm831x_fll_recalc_rate(struct clk_hw *hw, | 
|  | unsigned long parent_rate) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n", | 
|  | ret); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (ret & WM831X_FLL_AUTO) | 
|  | return wm831x_fll_auto_rates[ret & WM831X_FLL_AUTO_FREQ_MASK]; | 
|  |  | 
|  | dev_err(wm831x->dev, "FLL only supported in AUTO mode\n"); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static long wm831x_fll_round_rate(struct clk_hw *hw, unsigned long rate, | 
|  | unsigned long *unused) | 
|  | { | 
|  | int best = 0; | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++) | 
|  | if (abs(wm831x_fll_auto_rates[i] - rate) < | 
|  | abs(wm831x_fll_auto_rates[best] - rate)) | 
|  | best = i; | 
|  |  | 
|  | return wm831x_fll_auto_rates[best]; | 
|  | } | 
|  |  | 
|  | static int wm831x_fll_set_rate(struct clk_hw *hw, unsigned long rate, | 
|  | unsigned long parent_rate) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int i; | 
|  |  | 
|  | for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++) | 
|  | if (wm831x_fll_auto_rates[i] == rate) | 
|  | break; | 
|  | if (i == ARRAY_SIZE(wm831x_fll_auto_rates)) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (wm831x_fll_is_prepared(hw)) | 
|  | return -EPERM; | 
|  |  | 
|  | return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_2, | 
|  | WM831X_FLL_AUTO_FREQ_MASK, i); | 
|  | } | 
|  |  | 
|  | static const char *wm831x_fll_parents[] = { | 
|  | "xtal", | 
|  | "clkin", | 
|  | }; | 
|  |  | 
|  | static u8 wm831x_fll_get_parent(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | fll_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | /* AUTO mode is always clocked from the crystal */ | 
|  | ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n", | 
|  | ret); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (ret & WM831X_FLL_AUTO) | 
|  | return 0; | 
|  |  | 
|  | ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_5); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read FLL_CONTROL_5: %d\n", | 
|  | ret); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | switch (ret & WM831X_FLL_CLK_SRC_MASK) { | 
|  | case 0: | 
|  | return 0; | 
|  | case 1: | 
|  | return 1; | 
|  | default: | 
|  | dev_err(wm831x->dev, "Unsupported FLL clock source %d\n", | 
|  | ret & WM831X_FLL_CLK_SRC_MASK); | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | static const struct clk_ops wm831x_fll_ops = { | 
|  | .is_prepared = wm831x_fll_is_prepared, | 
|  | .prepare = wm831x_fll_prepare, | 
|  | .unprepare = wm831x_fll_unprepare, | 
|  | .round_rate = wm831x_fll_round_rate, | 
|  | .recalc_rate = wm831x_fll_recalc_rate, | 
|  | .set_rate = wm831x_fll_set_rate, | 
|  | .get_parent = wm831x_fll_get_parent, | 
|  | }; | 
|  |  | 
|  | static struct clk_init_data wm831x_fll_init = { | 
|  | .name = "fll", | 
|  | .ops = &wm831x_fll_ops, | 
|  | .parent_names = wm831x_fll_parents, | 
|  | .num_parents = ARRAY_SIZE(wm831x_fll_parents), | 
|  | .flags = CLK_SET_RATE_GATE, | 
|  | }; | 
|  |  | 
|  | static int wm831x_clkout_is_prepared(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | clkout_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n", | 
|  | ret); | 
|  | return true; | 
|  | } | 
|  |  | 
|  | return (ret & WM831X_CLKOUT_ENA) != 0; | 
|  | } | 
|  |  | 
|  | static int wm831x_clkout_prepare(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | clkout_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_unlock(wm831x); | 
|  | if (ret != 0) { | 
|  | dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1, | 
|  | WM831X_CLKOUT_ENA, WM831X_CLKOUT_ENA); | 
|  | if (ret != 0) | 
|  | dev_crit(wm831x->dev, "Failed to enable CLKOUT: %d\n", ret); | 
|  |  | 
|  | wm831x_reg_lock(wm831x); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void wm831x_clkout_unprepare(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | clkout_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_unlock(wm831x); | 
|  | if (ret != 0) { | 
|  | dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret); | 
|  | return; | 
|  | } | 
|  |  | 
|  | ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1, | 
|  | WM831X_CLKOUT_ENA, 0); | 
|  | if (ret != 0) | 
|  | dev_crit(wm831x->dev, "Failed to disable CLKOUT: %d\n", ret); | 
|  |  | 
|  | wm831x_reg_lock(wm831x); | 
|  | } | 
|  |  | 
|  | static const char *wm831x_clkout_parents[] = { | 
|  | "fll", | 
|  | "xtal", | 
|  | }; | 
|  |  | 
|  | static u8 wm831x_clkout_get_parent(struct clk_hw *hw) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | clkout_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  | int ret; | 
|  |  | 
|  | ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n", | 
|  | ret); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (ret & WM831X_CLKOUT_SRC) | 
|  | return 1; | 
|  | else | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int wm831x_clkout_set_parent(struct clk_hw *hw, u8 parent) | 
|  | { | 
|  | struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk, | 
|  | clkout_hw); | 
|  | struct wm831x *wm831x = clkdata->wm831x; | 
|  |  | 
|  | return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1, | 
|  | WM831X_CLKOUT_SRC, | 
|  | parent << WM831X_CLKOUT_SRC_SHIFT); | 
|  | } | 
|  |  | 
|  | static const struct clk_ops wm831x_clkout_ops = { | 
|  | .is_prepared = wm831x_clkout_is_prepared, | 
|  | .prepare = wm831x_clkout_prepare, | 
|  | .unprepare = wm831x_clkout_unprepare, | 
|  | .get_parent = wm831x_clkout_get_parent, | 
|  | .set_parent = wm831x_clkout_set_parent, | 
|  | }; | 
|  |  | 
|  | static struct clk_init_data wm831x_clkout_init = { | 
|  | .name = "clkout", | 
|  | .ops = &wm831x_clkout_ops, | 
|  | .parent_names = wm831x_clkout_parents, | 
|  | .num_parents = ARRAY_SIZE(wm831x_clkout_parents), | 
|  | .flags = CLK_SET_RATE_PARENT, | 
|  | }; | 
|  |  | 
|  | static int wm831x_clk_probe(struct platform_device *pdev) | 
|  | { | 
|  | struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); | 
|  | struct wm831x_clk *clkdata; | 
|  | int ret; | 
|  |  | 
|  | clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL); | 
|  | if (!clkdata) | 
|  | return -ENOMEM; | 
|  |  | 
|  | clkdata->wm831x = wm831x; | 
|  |  | 
|  | /* XTAL_ENA can only be set via OTP/InstantConfig so just read once */ | 
|  | ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2); | 
|  | if (ret < 0) { | 
|  | dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n", | 
|  | ret); | 
|  | return ret; | 
|  | } | 
|  | clkdata->xtal_ena = ret & WM831X_XTAL_ENA; | 
|  |  | 
|  | clkdata->xtal_hw.init = &wm831x_xtal_init; | 
|  | clkdata->xtal = devm_clk_register(&pdev->dev, &clkdata->xtal_hw); | 
|  | if (IS_ERR(clkdata->xtal)) | 
|  | return PTR_ERR(clkdata->xtal); | 
|  |  | 
|  | clkdata->fll_hw.init = &wm831x_fll_init; | 
|  | clkdata->fll = devm_clk_register(&pdev->dev, &clkdata->fll_hw); | 
|  | if (IS_ERR(clkdata->fll)) | 
|  | return PTR_ERR(clkdata->fll); | 
|  |  | 
|  | clkdata->clkout_hw.init = &wm831x_clkout_init; | 
|  | clkdata->clkout = devm_clk_register(&pdev->dev, &clkdata->clkout_hw); | 
|  | if (IS_ERR(clkdata->clkout)) | 
|  | return PTR_ERR(clkdata->clkout); | 
|  |  | 
|  | platform_set_drvdata(pdev, clkdata); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct platform_driver wm831x_clk_driver = { | 
|  | .probe = wm831x_clk_probe, | 
|  | .driver		= { | 
|  | .name	= "wm831x-clk", | 
|  | }, | 
|  | }; | 
|  |  | 
|  | module_platform_driver(wm831x_clk_driver); | 
|  |  | 
|  | /* Module information */ | 
|  | MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); | 
|  | MODULE_DESCRIPTION("WM831x clock driver"); | 
|  | MODULE_LICENSE("GPL"); | 
|  | MODULE_ALIAS("platform:wm831x-clk"); |