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Diffstat (limited to 'drivers/clk/clk-fsl-sai.c')
-rw-r--r--drivers/clk/clk-fsl-sai.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/clk/clk-fsl-sai.c b/drivers/clk/clk-fsl-sai.c
new file mode 100644
index 000000000..6238fcea0
--- /dev/null
+++ b/drivers/clk/clk-fsl-sai.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Freescale SAI BCLK as a generic clock driver
+ *
+ * Copyright 2020 Michael Walle <michael@walle.cc>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+
+#define I2S_CSR 0x00
+#define I2S_CR2 0x08
+#define CSR_BCE_BIT 28
+#define CR2_BCD BIT(24)
+#define CR2_DIV_SHIFT 0
+#define CR2_DIV_WIDTH 8
+
+struct fsl_sai_clk {
+ struct clk_divider div;
+ struct clk_gate gate;
+ spinlock_t lock;
+};
+
+static int fsl_sai_clk_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct fsl_sai_clk *sai_clk;
+ struct clk_parent_data pdata = { .index = 0 };
+ void __iomem *base;
+ struct clk_hw *hw;
+ struct resource *res;
+
+ sai_clk = devm_kzalloc(dev, sizeof(*sai_clk), GFP_KERNEL);
+ if (!sai_clk)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ spin_lock_init(&sai_clk->lock);
+
+ sai_clk->gate.reg = base + I2S_CSR;
+ sai_clk->gate.bit_idx = CSR_BCE_BIT;
+ sai_clk->gate.lock = &sai_clk->lock;
+
+ sai_clk->div.reg = base + I2S_CR2;
+ sai_clk->div.shift = CR2_DIV_SHIFT;
+ sai_clk->div.width = CR2_DIV_WIDTH;
+ sai_clk->div.lock = &sai_clk->lock;
+
+ /* set clock direction, we are the BCLK master */
+ writel(CR2_BCD, base + I2S_CR2);
+
+ hw = devm_clk_hw_register_composite_pdata(dev, dev->of_node->name,
+ &pdata, 1, NULL, NULL,
+ &sai_clk->div.hw,
+ &clk_divider_ops,
+ &sai_clk->gate.hw,
+ &clk_gate_ops,
+ CLK_SET_RATE_GATE);
+ if (IS_ERR(hw))
+ return PTR_ERR(hw);
+
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);
+}
+
+static const struct of_device_id of_fsl_sai_clk_ids[] = {
+ { .compatible = "fsl,vf610-sai-clock" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, of_fsl_sai_clk_ids);
+
+static struct platform_driver fsl_sai_clk_driver = {
+ .probe = fsl_sai_clk_probe,
+ .driver = {
+ .name = "fsl-sai-clk",
+ .of_match_table = of_fsl_sai_clk_ids,
+ },
+};
+module_platform_driver(fsl_sai_clk_driver);
+
+MODULE_DESCRIPTION("Freescale SAI bitclock-as-a-clock driver");
+MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:fsl-sai-clk");