Initial import

1 files changed, 306 insertions, 0 deletions

diff --git a/drivers/clk/clk-palmas.c b/drivers/clk/clk-palmas.c
new file mode 100644
index 000000000..45a535ab4
--- /dev/null
+++ b/drivers/clk/clk-palmas.c
@@ -0,0 +1,306 @@
+/*
+ * Clock driver for Palmas device.
+ *
+ * Copyright (c) 2013, NVIDIA Corporation.
+ * Copyright (c) 2013-2014 Texas Instruments, Inc.
+ *
+ * Author:	Laxman Dewangan <ldewangan@nvidia.com>
+ *		Peter Ujfalusi <peter.ujfalusi@ti.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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind,
+ * whether express or implied; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/mfd/palmas.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1	1
+#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2	2
+#define PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP	3
+
+struct palmas_clk32k_desc {
+	const char *clk_name;
+	unsigned int control_reg;
+	unsigned int enable_mask;
+	unsigned int sleep_mask;
+	unsigned int sleep_reqstr_id;
+	int delay;
+};
+
+struct palmas_clock_info {
+	struct device *dev;
+	struct clk *clk;
+	struct clk_hw hw;
+	struct palmas *palmas;
+	struct palmas_clk32k_desc *clk_desc;
+	int ext_control_pin;
+};
+
+static inline struct palmas_clock_info *to_palmas_clks_info(struct clk_hw *hw)
+{
+	return container_of(hw, struct palmas_clock_info, hw);
+}
+
+static unsigned long palmas_clks_recalc_rate(struct clk_hw *hw,
+					     unsigned long parent_rate)
+{
+	return 32768;
+}
+
+static int palmas_clks_prepare(struct clk_hw *hw)
+{
+	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
+	int ret;
+
+	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
+				 cinfo->clk_desc->control_reg,
+				 cinfo->clk_desc->enable_mask,
+				 cinfo->clk_desc->enable_mask);
+	if (ret < 0)
+		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
+			cinfo->clk_desc->control_reg, ret);
+	else if (cinfo->clk_desc->delay)
+		udelay(cinfo->clk_desc->delay);
+
+	return ret;
+}
+
+static void palmas_clks_unprepare(struct clk_hw *hw)
+{
+	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
+	int ret;
+
+	/*
+	 * Clock can be disabled through external pin if it is externally
+	 * controlled.
+	 */
+	if (cinfo->ext_control_pin)
+		return;
+
+	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
+				 cinfo->clk_desc->control_reg,
+				 cinfo->clk_desc->enable_mask, 0);
+	if (ret < 0)
+		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
+			cinfo->clk_desc->control_reg, ret);
+}
+
+static int palmas_clks_is_prepared(struct clk_hw *hw)
+{
+	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
+	int ret;
+	u32 val;
+
+	if (cinfo->ext_control_pin)
+		return 1;
+
+	ret = palmas_read(cinfo->palmas, PALMAS_RESOURCE_BASE,
+			  cinfo->clk_desc->control_reg, &val);
+	if (ret < 0) {
+		dev_err(cinfo->dev, "Reg 0x%02x read failed, %d\n",
+			cinfo->clk_desc->control_reg, ret);
+		return ret;
+	}
+	return !!(val & cinfo->clk_desc->enable_mask);
+}
+
+static struct clk_ops palmas_clks_ops = {
+	.prepare	= palmas_clks_prepare,
+	.unprepare	= palmas_clks_unprepare,
+	.is_prepared	= palmas_clks_is_prepared,
+	.recalc_rate	= palmas_clks_recalc_rate,
+};
+
+struct palmas_clks_of_match_data {
+	struct clk_init_data init;
+	struct palmas_clk32k_desc desc;
+};
+
+static struct palmas_clks_of_match_data palmas_of_clk32kg = {
+	.init = {
+		.name = "clk32kg",
+		.ops = &palmas_clks_ops,
+		.flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED,
+	},
+	.desc = {
+		.clk_name = "clk32kg",
+		.control_reg = PALMAS_CLK32KG_CTRL,
+		.enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE,
+		.sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP,
+		.sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KG,
+		.delay = 200,
+	},
+};
+
+static struct palmas_clks_of_match_data palmas_of_clk32kgaudio = {
+	.init = {
+		.name = "clk32kgaudio",
+		.ops = &palmas_clks_ops,
+		.flags = CLK_IS_ROOT | CLK_IGNORE_UNUSED,
+	},
+	.desc = {
+		.clk_name = "clk32kgaudio",
+		.control_reg = PALMAS_CLK32KGAUDIO_CTRL,
+		.enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE,
+		.sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP,
+		.sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KGAUDIO,
+		.delay = 200,
+	},
+};
+
+static const struct of_device_id palmas_clks_of_match[] = {
+	{
+		.compatible = "ti,palmas-clk32kg",
+		.data = &palmas_of_clk32kg,
+	},
+	{
+		.compatible = "ti,palmas-clk32kgaudio",
+		.data = &palmas_of_clk32kgaudio,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, palmas_clks_of_match);
+
+static void palmas_clks_get_clk_data(struct platform_device *pdev,
+				     struct palmas_clock_info *cinfo)
+{
+	struct device_node *node = pdev->dev.of_node;
+	unsigned int prop;
+	int ret;
+
+	ret = of_property_read_u32(node, "ti,external-sleep-control",
+				   &prop);
+	if (ret)
+		return;
+
+	switch (prop) {
+	case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1:
+		prop = PALMAS_EXT_CONTROL_ENABLE1;
+		break;
+	case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2:
+		prop = PALMAS_EXT_CONTROL_ENABLE2;
+		break;
+	case PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP:
+		prop = PALMAS_EXT_CONTROL_NSLEEP;
+		break;
+	default:
+		dev_warn(&pdev->dev, "%s: Invalid ext control option: %u\n",
+			 node->name, prop);
+		prop = 0;
+		break;
+	}
+	cinfo->ext_control_pin = prop;
+}
+
+static int palmas_clks_init_configure(struct palmas_clock_info *cinfo)
+{
+	int ret;
+
+	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
+				 cinfo->clk_desc->control_reg,
+				 cinfo->clk_desc->sleep_mask, 0);
+	if (ret < 0) {
+		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
+			cinfo->clk_desc->control_reg, ret);
+		return ret;
+	}
+
+	if (cinfo->ext_control_pin) {
+		ret = clk_prepare(cinfo->clk);
+		if (ret < 0) {
+			dev_err(cinfo->dev, "Clock prep failed, %d\n", ret);
+			return ret;
+		}
+
+		ret = palmas_ext_control_req_config(cinfo->palmas,
+					cinfo->clk_desc->sleep_reqstr_id,
+					cinfo->ext_control_pin, true);
+		if (ret < 0) {
+			dev_err(cinfo->dev, "Ext config for %s failed, %d\n",
+				cinfo->clk_desc->clk_name, ret);
+			return ret;
+		}
+	}
+
+	return ret;
+}
+static int palmas_clks_probe(struct platform_device *pdev)
+{
+	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
+	struct device_node *node = pdev->dev.of_node;
+	struct palmas_clks_of_match_data *match_data;
+	const struct of_device_id *match;
+	struct palmas_clock_info *cinfo;
+	struct clk *clk;
+	int ret;
+
+	match = of_match_device(palmas_clks_of_match, &pdev->dev);
+	match_data = (struct palmas_clks_of_match_data *)match->data;
+
+	cinfo = devm_kzalloc(&pdev->dev, sizeof(*cinfo), GFP_KERNEL);
+	if (!cinfo)
+		return -ENOMEM;
+
+	palmas_clks_get_clk_data(pdev, cinfo);
+	platform_set_drvdata(pdev, cinfo);
+
+	cinfo->dev = &pdev->dev;
+	cinfo->palmas = palmas;
+
+	cinfo->clk_desc = &match_data->desc;
+	cinfo->hw.init = &match_data->init;
+	clk = devm_clk_register(&pdev->dev, &cinfo->hw);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		dev_err(&pdev->dev, "Fail to register clock %s, %d\n",
+			match_data->desc.clk_name, ret);
+		return ret;
+	}
+
+	cinfo->clk = clk;
+	ret = palmas_clks_init_configure(cinfo);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Clock config failed, %d\n", ret);
+		return ret;
+	}
+
+	ret = of_clk_add_provider(node, of_clk_src_simple_get, cinfo->clk);
+	if (ret < 0)
+		dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret);
+	return ret;
+}
+
+static int palmas_clks_remove(struct platform_device *pdev)
+{
+	of_clk_del_provider(pdev->dev.of_node);
+	return 0;
+}
+
+static struct platform_driver palmas_clks_driver = {
+	.driver = {
+		.name = "palmas-clk",
+		.of_match_table = palmas_clks_of_match,
+	},
+	.probe = palmas_clks_probe,
+	.remove = palmas_clks_remove,
+};
+
+module_platform_driver(palmas_clks_driver);
+
+MODULE_DESCRIPTION("Clock driver for Palmas Series Devices");
+MODULE_ALIAS("platform:palmas-clk");
+MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
+MODULE_LICENSE("GPL v2");