aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorHans Verkuil <hverkuil@xs4all.nl>2021-07-19 11:19:30 +0200
committerHans Verkuil <hverkuil@xs4all.nl>2021-09-09 10:07:17 +0200
commit4aba42a6423dfe22e71b7bbf4bcf139be02992a2 (patch)
tree9bb5413a0b947e55b29ae317dac4675f87c471fb
parentb00c8a030602dd12a092ff75121fd101fcd20370 (diff)
clk-hifiberry-dacpro: add support for the Hifiberry DAC+ ADC
Adds support for the clock on the Hifiberry DAC+ ADC. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
-rw-r--r--drivers/clk/Kconfig3
-rw-r--r--drivers/clk/Makefile1
-rw-r--r--drivers/clk/clk-hifiberry-dacpro.c160
3 files changed, 164 insertions, 0 deletions
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index e873f9ea2e65..56ff4afe5eaf 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -90,6 +90,9 @@ config COMMON_CLK_HI655X
multi-function device has one fixed-rate oscillator, clocked
at 32KHz.
+config COMMON_CLK_HIFIBERRY_DACPRO
+ tristate
+
config COMMON_CLK_SCMI
tristate "Clock driver controlled via SCMI interface"
depends on ARM_SCMI_PROTOCOL || COMPILE_TEST
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 2b91d34c582b..939b1e9e1168 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_CLK_HSDK) += clk-hsdk-pll.o
obj-$(CONFIG_COMMON_CLK_K210) += clk-k210.o
obj-$(CONFIG_LMK04832) += clk-lmk04832.o
obj-$(CONFIG_COMMON_CLK_LOCHNAGAR) += clk-lochnagar.o
+obj-$(CONFIG_COMMON_CLK_HIFIBERRY_DACPRO) += clk-hifiberry-dacpro.o
obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
obj-$(CONFIG_COMMON_CLK_MAX9485) += clk-max9485.o
obj-$(CONFIG_ARCH_MILBEAUT_M10V) += clk-milbeaut.o
diff --git a/drivers/clk/clk-hifiberry-dacpro.c b/drivers/clk/clk-hifiberry-dacpro.c
new file mode 100644
index 000000000000..e60b64f63de3
--- /dev/null
+++ b/drivers/clk/clk-hifiberry-dacpro.c
@@ -0,0 +1,160 @@
+/*
+ * Clock Driver for HiFiBerry DAC Pro
+ *
+ * Author: Stuart MacLean
+ * Copyright 2015
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; 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-provider.h>
+#include <linux/clkdev.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+
+/* Clock rate of CLK44EN attached to GPIO6 pin */
+#define CLK_44EN_RATE 22579200UL
+/* Clock rate of CLK48EN attached to GPIO3 pin */
+#define CLK_48EN_RATE 24576000UL
+
+/**
+ * struct clk_hifiberry_hw - Common struct to the HiFiBerry DAC Pro
+ * @hw: clk_hw for the common clk framework
+ * @mode: 0 => CLK44EN, 1 => CLK48EN
+ */
+struct clk_hifiberry_hw {
+ struct clk_hw hw;
+ uint8_t mode;
+};
+
+#define to_hifiberry_clk(_hw) container_of(_hw, struct clk_hifiberry_hw, hw)
+
+static const struct of_device_id clk_hifiberry_dacpro_dt_ids[] = {
+ { .compatible = "hifiberry,dacpro-clk",},
+ { }
+};
+MODULE_DEVICE_TABLE(of, clk_hifiberry_dacpro_dt_ids);
+
+static unsigned long clk_hifiberry_dacpro_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return (to_hifiberry_clk(hw)->mode == 0) ? CLK_44EN_RATE :
+ CLK_48EN_RATE;
+}
+
+static long clk_hifiberry_dacpro_round_rate(struct clk_hw *hw,
+ unsigned long rate, unsigned long *parent_rate)
+{
+ long actual_rate;
+
+ if (rate <= CLK_44EN_RATE) {
+ actual_rate = (long)CLK_44EN_RATE;
+ } else if (rate >= CLK_48EN_RATE) {
+ actual_rate = (long)CLK_48EN_RATE;
+ } else {
+ long diff44Rate = (long)(rate - CLK_44EN_RATE);
+ long diff48Rate = (long)(CLK_48EN_RATE - rate);
+
+ if (diff44Rate < diff48Rate)
+ actual_rate = (long)CLK_44EN_RATE;
+ else
+ actual_rate = (long)CLK_48EN_RATE;
+ }
+ return actual_rate;
+}
+
+
+static int clk_hifiberry_dacpro_set_rate(struct clk_hw *hw,
+ unsigned long rate, unsigned long parent_rate)
+{
+ unsigned long actual_rate;
+ struct clk_hifiberry_hw *clk = to_hifiberry_clk(hw);
+
+ actual_rate = (unsigned long)clk_hifiberry_dacpro_round_rate(hw, rate,
+ &parent_rate);
+ clk->mode = (actual_rate == CLK_44EN_RATE) ? 0 : 1;
+ return 0;
+}
+
+
+const struct clk_ops clk_hifiberry_dacpro_rate_ops = {
+ .recalc_rate = clk_hifiberry_dacpro_recalc_rate,
+ .round_rate = clk_hifiberry_dacpro_round_rate,
+ .set_rate = clk_hifiberry_dacpro_set_rate,
+};
+
+static int clk_hifiberry_dacpro_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct clk_hifiberry_hw *proclk;
+ struct clk *clk;
+ struct device *dev;
+ struct clk_init_data init;
+
+ dev = &pdev->dev;
+
+ proclk = kzalloc(sizeof(struct clk_hifiberry_hw), GFP_KERNEL);
+ if (!proclk)
+ return -ENOMEM;
+
+ init.name = "clk-hifiberry-dacpro";
+ init.ops = &clk_hifiberry_dacpro_rate_ops;
+ init.flags = 0;
+ init.parent_names = NULL;
+ init.num_parents = 0;
+
+ proclk->mode = 0;
+ proclk->hw.init = &init;
+
+ clk = devm_clk_register(dev, &proclk->hw);
+ if (!IS_ERR(clk)) {
+ ret = of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
+ clk);
+ } else {
+ dev_err(dev, "Fail to register clock driver\n");
+ kfree(proclk);
+ ret = PTR_ERR(clk);
+ }
+ return ret;
+}
+
+static int clk_hifiberry_dacpro_remove(struct platform_device *pdev)
+{
+ of_clk_del_provider(pdev->dev.of_node);
+ return 0;
+}
+
+static struct platform_driver clk_hifiberry_dacpro_driver = {
+ .probe = clk_hifiberry_dacpro_probe,
+ .remove = clk_hifiberry_dacpro_remove,
+ .driver = {
+ .name = "clk-hifiberry-dacpro",
+ .of_match_table = clk_hifiberry_dacpro_dt_ids,
+ },
+};
+
+static int __init clk_hifiberry_dacpro_init(void)
+{
+ return platform_driver_register(&clk_hifiberry_dacpro_driver);
+}
+core_initcall(clk_hifiberry_dacpro_init);
+
+static void __exit clk_hifiberry_dacpro_exit(void)
+{
+ platform_driver_unregister(&clk_hifiberry_dacpro_driver);
+}
+module_exit(clk_hifiberry_dacpro_exit);
+
+MODULE_DESCRIPTION("HiFiBerry DAC Pro clock driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:clk-hifiberry-dacpro");

Privacy Policy