1 files changed, 398 insertions, 0 deletions
diff --git a/drivers/clk/clk-wm831x.c b/drivers/clk/clk-wm831x.c
new file mode 100644
index 000000000..ae6dd38ec
--- /dev/null
+++ b/drivers/clk/clk-wm831x.c
@@ -0,0 +1,398 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * WM831x clock control
+ *
+ * Copyright 2011-2 Wolfson Microelectronics PLC.
+ *
+ * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
+ */
+
+#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;
+	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 const struct clk_init_data wm831x_xtal_init = {
+	.name = "xtal",
+	.ops = &wm831x_xtal_ops,
+};
+
+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);
+
+	/* wait 2-3 ms for new frequency taking effect */
+	usleep_range(2000, 3000);
+
+	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 const 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 false;
+	}
+
+	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 const 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;
+	ret = devm_clk_hw_register(&pdev->dev, &clkdata->xtal_hw);
+	if (ret)
+		return ret;
+
+	clkdata->fll_hw.init = &wm831x_fll_init;
+	ret = devm_clk_hw_register(&pdev->dev, &clkdata->fll_hw);
+	if (ret)
+		return ret;
+
+	clkdata->clkout_hw.init = &wm831x_clkout_init;
+	ret = devm_clk_hw_register(&pdev->dev, &clkdata->clkout_hw);
+	if (ret)
+		return ret;
+
+	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");