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-rw-r--r--drivers/clk/clk-bd718x7.c164
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/clk/clk-bd718x7.c b/drivers/clk/clk-bd718x7.c
new file mode 100644
index 000000000..b52e8d6f6
--- /dev/null
+++ b/drivers/clk/clk-bd718x7.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 ROHM Semiconductors
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mfd/rohm-generic.h>
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/regmap.h>
+
+/* clk control registers */
+/* BD70528 */
+#define BD70528_REG_OUT32K 0x2c
+/* BD71828 */
+#define BD71828_REG_OUT32K 0x4B
+/* BD71837 and BD71847 */
+#define BD718XX_REG_OUT32K 0x2E
+
+/*
+ * BD71837, BD71847, BD70528 and BD71828 all use bit [0] to clk output control
+ */
+#define CLK_OUT_EN_MASK BIT(0)
+
+
+struct bd718xx_clk {
+ struct clk_hw hw;
+ u8 reg;
+ u8 mask;
+ struct platform_device *pdev;
+ struct rohm_regmap_dev *mfd;
+};
+
+static int bd71837_clk_set(struct bd718xx_clk *c, unsigned int status)
+{
+ return regmap_update_bits(c->mfd->regmap, c->reg, c->mask, status);
+}
+
+static void bd71837_clk_disable(struct clk_hw *hw)
+{
+ int rv;
+ struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
+
+ rv = bd71837_clk_set(c, 0);
+ if (rv)
+ dev_dbg(&c->pdev->dev, "Failed to disable 32K clk (%d)\n", rv);
+}
+
+static int bd71837_clk_enable(struct clk_hw *hw)
+{
+ struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
+
+ return bd71837_clk_set(c, 0xffffffff);
+}
+
+static int bd71837_clk_is_enabled(struct clk_hw *hw)
+{
+ int enabled;
+ int rval;
+ struct bd718xx_clk *c = container_of(hw, struct bd718xx_clk, hw);
+
+ rval = regmap_read(c->mfd->regmap, c->reg, &enabled);
+
+ if (rval)
+ return rval;
+
+ return enabled & c->mask;
+}
+
+static const struct clk_ops bd71837_clk_ops = {
+ .prepare = &bd71837_clk_enable,
+ .unprepare = &bd71837_clk_disable,
+ .is_prepared = &bd71837_clk_is_enabled,
+};
+
+static int bd71837_clk_probe(struct platform_device *pdev)
+{
+ struct bd718xx_clk *c;
+ int rval = -ENOMEM;
+ const char *parent_clk;
+ struct device *parent = pdev->dev.parent;
+ struct rohm_regmap_dev *mfd = dev_get_drvdata(parent);
+ struct clk_init_data init = {
+ .name = "bd718xx-32k-out",
+ .ops = &bd71837_clk_ops,
+ };
+ enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
+
+ c = devm_kzalloc(&pdev->dev, sizeof(*c), GFP_KERNEL);
+ if (!c)
+ return -ENOMEM;
+
+ init.num_parents = 1;
+ parent_clk = of_clk_get_parent_name(parent->of_node, 0);
+
+ init.parent_names = &parent_clk;
+ if (!parent_clk) {
+ dev_err(&pdev->dev, "No parent clk found\n");
+ return -EINVAL;
+ }
+ switch (chip) {
+ case ROHM_CHIP_TYPE_BD71837:
+ case ROHM_CHIP_TYPE_BD71847:
+ c->reg = BD718XX_REG_OUT32K;
+ c->mask = CLK_OUT_EN_MASK;
+ break;
+ case ROHM_CHIP_TYPE_BD71828:
+ c->reg = BD71828_REG_OUT32K;
+ c->mask = CLK_OUT_EN_MASK;
+ break;
+ case ROHM_CHIP_TYPE_BD70528:
+ c->reg = BD70528_REG_OUT32K;
+ c->mask = CLK_OUT_EN_MASK;
+ break;
+ default:
+ dev_err(&pdev->dev, "Unknown clk chip\n");
+ return -EINVAL;
+ }
+ c->mfd = mfd;
+ c->pdev = pdev;
+ c->hw.init = &init;
+
+ of_property_read_string_index(parent->of_node,
+ "clock-output-names", 0, &init.name);
+
+ rval = devm_clk_hw_register(&pdev->dev, &c->hw);
+ if (rval) {
+ dev_err(&pdev->dev, "failed to register 32K clk");
+ return rval;
+ }
+ rval = devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get,
+ &c->hw);
+ if (rval)
+ dev_err(&pdev->dev, "adding clk provider failed\n");
+
+ return rval;
+}
+
+static const struct platform_device_id bd718x7_clk_id[] = {
+ { "bd71837-clk", ROHM_CHIP_TYPE_BD71837 },
+ { "bd71847-clk", ROHM_CHIP_TYPE_BD71847 },
+ { "bd70528-clk", ROHM_CHIP_TYPE_BD70528 },
+ { "bd71828-clk", ROHM_CHIP_TYPE_BD71828 },
+ { },
+};
+MODULE_DEVICE_TABLE(platform, bd718x7_clk_id);
+
+static struct platform_driver bd71837_clk = {
+ .driver = {
+ .name = "bd718xx-clk",
+ },
+ .probe = bd71837_clk_probe,
+ .id_table = bd718x7_clk_id,
+};
+
+module_platform_driver(bd71837_clk);
+
+MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");
+MODULE_DESCRIPTION("BD71837/BD71847/BD70528 chip clk driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:bd718xx-clk");