[PATCH v3 2/9] clk: samsung: add clock driver for external clock outputs
Heiko Stübner
heiko at sntech.de
Sun May 11 15:06:25 PDT 2014
This adds a driver for controlling the external clock outputs of
s3c24xx architectures including the dclk muxes and dividers.
The driver at the moment only supports the legacy non-dt boards using these
clock outputs. The clock-output control itself is part of the system-controller
mainly controlled by the pinctrl drivers. So it should most likely be
integrated there for dt platforms.
Signed-off-by: Heiko Stuebner <heiko at sntech.de>
Acked-by: Mike Turquette <mturquette at linaro.org>
Acked-by: Tomasz Figa <t.figa at samsung.com>
---
drivers/clk/samsung/Makefile | 1 +
drivers/clk/samsung/clk-s3c2410-dclk.c | 440 +++++++++++++++++++++++++++++++++
2 files changed, 441 insertions(+)
create mode 100644 drivers/clk/samsung/clk-s3c2410-dclk.c
diff --git a/drivers/clk/samsung/Makefile b/drivers/clk/samsung/Makefile
index 56e7d38..28ba4eb 100644
--- a/drivers/clk/samsung/Makefile
+++ b/drivers/clk/samsung/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_SOC_EXYNOS5260) += clk-exynos5260.o
obj-$(CONFIG_SOC_EXYNOS5420) += clk-exynos5420.o
obj-$(CONFIG_SOC_EXYNOS5440) += clk-exynos5440.o
obj-$(CONFIG_ARCH_EXYNOS) += clk-exynos-audss.o
+obj-$(CONFIG_S3C2410_COMMON_DCLK)+= clk-s3c2410-dclk.o
obj-$(CONFIG_S3C2412_COMMON_CLK)+= clk-s3c2412.o
obj-$(CONFIG_S3C2443_COMMON_CLK)+= clk-s3c2443.o
obj-$(CONFIG_ARCH_S3C64XX) += clk-s3c64xx.o
diff --git a/drivers/clk/samsung/clk-s3c2410-dclk.c b/drivers/clk/samsung/clk-s3c2410-dclk.c
new file mode 100644
index 0000000..8d8dff0
--- /dev/null
+++ b/drivers/clk/samsung/clk-s3c2410-dclk.c
@@ -0,0 +1,440 @@
+/*
+ * Copyright (c) 2013 Heiko Stuebner <heiko at sntech.de>
+ *
+ * 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.
+ *
+ * Common Clock Framework support for s3c24xx external clock output.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include "clk.h"
+
+/* legacy access to misccr, until dt conversion is finished */
+#include <mach/hardware.h>
+#include <mach/regs-gpio.h>
+
+#define MUX_DCLK0 0
+#define MUX_DCLK1 1
+#define DIV_DCLK0 2
+#define DIV_DCLK1 3
+#define GATE_DCLK0 4
+#define GATE_DCLK1 5
+#define MUX_CLKOUT0 6
+#define MUX_CLKOUT1 7
+#define DCLK_MAX_CLKS (MUX_CLKOUT1 + 1)
+
+enum supported_socs {
+ S3C2410,
+ S3C2412,
+ S3C2440,
+ S3C2443,
+};
+
+struct s3c24xx_dclk_drv_data {
+ const char **clkout0_parent_names;
+ int clkout0_num_parents;
+ const char **clkout1_parent_names;
+ int clkout1_num_parents;
+ const char **mux_parent_names;
+ int mux_num_parents;
+};
+
+/*
+ * Clock for output-parent selection in misccr
+ */
+
+struct s3c24xx_clkout {
+ struct clk_hw hw;
+ u32 mask;
+ u8 shift;
+};
+
+#define to_s3c24xx_clkout(_hw) container_of(_hw, struct s3c24xx_clkout, hw)
+
+static u8 s3c24xx_clkout_get_parent(struct clk_hw *hw)
+{
+ struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
+ int num_parents = __clk_get_num_parents(hw->clk);
+ u32 val;
+
+ val = readl_relaxed(S3C24XX_MISCCR) >> clkout->shift;
+ val >>= clkout->shift;
+ val &= clkout->mask;
+
+ if (val >= num_parents)
+ return -EINVAL;
+
+ return val;
+}
+
+static int s3c24xx_clkout_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct s3c24xx_clkout *clkout = to_s3c24xx_clkout(hw);
+ int ret = 0;
+
+ s3c2410_modify_misccr((clkout->mask << clkout->shift),
+ (index << clkout->shift));
+
+ return ret;
+}
+
+const struct clk_ops s3c24xx_clkout_ops = {
+ .get_parent = s3c24xx_clkout_get_parent,
+ .set_parent = s3c24xx_clkout_set_parent,
+ .determine_rate = __clk_mux_determine_rate,
+};
+
+struct clk *s3c24xx_register_clkout(struct device *dev, const char *name,
+ const char **parent_names, u8 num_parents,
+ u8 shift, u32 mask)
+{
+ struct s3c24xx_clkout *clkout;
+ struct clk *clk;
+ struct clk_init_data init;
+
+ /* allocate the clkout */
+ clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
+ if (!clkout)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &s3c24xx_clkout_ops;
+ init.flags = CLK_IS_BASIC;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+
+ clkout->shift = shift;
+ clkout->mask = mask;
+ clkout->hw.init = &init;
+
+ clk = clk_register(dev, &clkout->hw);
+
+ return clk;
+}
+
+/*
+ * dclk and clkout init
+ */
+
+struct s3c24xx_dclk {
+ struct device *dev;
+ void __iomem *base;
+ struct clk_onecell_data clk_data;
+ struct notifier_block dclk0_div_change_nb;
+ struct notifier_block dclk1_div_change_nb;
+ spinlock_t dclk_lock;
+ unsigned long reg_save;
+};
+
+#define to_s3c24xx_dclk0(x) \
+ container_of(x, struct s3c24xx_dclk, dclk0_div_change_nb)
+
+#define to_s3c24xx_dclk1(x) \
+ container_of(x, struct s3c24xx_dclk, dclk1_div_change_nb)
+
+PNAME(dclk_s3c2410_p) = { "pclk", "uclk" };
+PNAME(clkout0_s3c2410_p) = { "mpll", "upll", "fclk", "hclk", "pclk",
+ "gate_dclk0" };
+PNAME(clkout1_s3c2410_p) = { "mpll", "upll", "fclk", "hclk", "pclk",
+ "gate_dclk1" };
+
+PNAME(clkout0_s3c2412_p) = { "mpll", "upll", "rtc_clkout",
+ "hclk", "pclk", "gate_dclk0" };
+PNAME(clkout1_s3c2412_p) = { "xti", "upll", "fclk", "hclk", "pclk",
+ "gate_dclk1" };
+
+PNAME(clkout0_s3c2440_p) = { "xti", "upll", "fclk", "hclk", "pclk",
+ "gate_dclk0" };
+PNAME(clkout1_s3c2440_p) = { "mpll", "upll", "rtc_clkout",
+ "hclk", "pclk", "gate_dclk1" };
+
+PNAME(dclk_s3c2443_p) = { "pclk", "epll" };
+PNAME(clkout0_s3c2443_p) = { "xti", "epll", "armclk", "hclk", "pclk",
+ "gate_dclk0" };
+PNAME(clkout1_s3c2443_p) = { "dummy", "epll", "rtc_clkout",
+ "hclk", "pclk", "gate_dclk1" };
+
+#define DCLKCON_DCLK_DIV_MASK 0xf
+#define DCLKCON_DCLK0_DIV_SHIFT 4
+#define DCLKCON_DCLK0_CMP_SHIFT 8
+#define DCLKCON_DCLK1_DIV_SHIFT 20
+#define DCLKCON_DCLK1_CMP_SHIFT 24
+
+static void s3c24xx_dclk_update_cmp(struct s3c24xx_dclk *s3c24xx_dclk,
+ int div_shift, int cmp_shift)
+{
+ unsigned long flags = 0;
+ u32 dclk_con, div, cmp;
+
+ spin_lock_irqsave(&s3c24xx_dclk->dclk_lock, flags);
+
+ dclk_con = readl_relaxed(s3c24xx_dclk->base);
+
+ div = ((dclk_con >> div_shift) & DCLKCON_DCLK_DIV_MASK) + 1;
+ cmp = ((div + 1) / 2) - 1;
+
+ dclk_con &= ~(DCLKCON_DCLK_DIV_MASK << cmp_shift);
+ dclk_con |= (cmp << cmp_shift);
+
+ writel_relaxed(dclk_con, s3c24xx_dclk->base);
+
+ spin_unlock_irqrestore(&s3c24xx_dclk->dclk_lock, flags);
+}
+
+static int s3c24xx_dclk0_div_notify(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk0(nb);
+
+ if (event == POST_RATE_CHANGE) {
+ s3c24xx_dclk_update_cmp(s3c24xx_dclk,
+ DCLKCON_DCLK0_DIV_SHIFT, DCLKCON_DCLK0_CMP_SHIFT);
+ }
+
+ return NOTIFY_DONE;
+}
+
+static int s3c24xx_dclk1_div_notify(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct s3c24xx_dclk *s3c24xx_dclk = to_s3c24xx_dclk1(nb);
+
+ if (event == POST_RATE_CHANGE) {
+ s3c24xx_dclk_update_cmp(s3c24xx_dclk,
+ DCLKCON_DCLK1_DIV_SHIFT, DCLKCON_DCLK1_CMP_SHIFT);
+ }
+
+ return NOTIFY_DONE;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int s3c24xx_dclk_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
+
+ s3c24xx_dclk->reg_save = readl_relaxed(s3c24xx_dclk->base);
+ return 0;
+}
+
+static int s3c24xx_dclk_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
+
+ writel_relaxed(s3c24xx_dclk->reg_save, s3c24xx_dclk->base);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(s3c24xx_dclk_pm_ops,
+ s3c24xx_dclk_suspend, s3c24xx_dclk_resume);
+
+static int s3c24xx_dclk_probe(struct platform_device *pdev)
+{
+ struct s3c24xx_dclk *s3c24xx_dclk;
+ struct resource *mem;
+ struct clk **clk_table;
+ struct s3c24xx_dclk_drv_data *dclk_variant;
+ int ret, i;
+
+ s3c24xx_dclk = devm_kzalloc(&pdev->dev, sizeof(*s3c24xx_dclk),
+ GFP_KERNEL);
+ if (!s3c24xx_dclk)
+ return -ENOMEM;
+
+ s3c24xx_dclk->dev = &pdev->dev;
+ platform_set_drvdata(pdev, s3c24xx_dclk);
+ spin_lock_init(&s3c24xx_dclk->dclk_lock);
+
+ clk_table = devm_kzalloc(&pdev->dev,
+ sizeof(struct clk *) * DCLK_MAX_CLKS,
+ GFP_KERNEL);
+ if (!clk_table)
+ return -ENOMEM;
+
+ s3c24xx_dclk->clk_data.clks = clk_table;
+ s3c24xx_dclk->clk_data.clk_num = DCLK_MAX_CLKS;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ s3c24xx_dclk->base = devm_ioremap_resource(&pdev->dev, mem);
+ if (IS_ERR(s3c24xx_dclk->base))
+ return PTR_ERR(s3c24xx_dclk->base);
+
+ dclk_variant = (struct s3c24xx_dclk_drv_data *)
+ platform_get_device_id(pdev)->driver_data;
+
+
+ clk_table[MUX_DCLK0] = clk_register_mux(&pdev->dev, "mux_dclk0",
+ dclk_variant->mux_parent_names,
+ dclk_variant->mux_num_parents, 0,
+ s3c24xx_dclk->base, 1, 1, 0,
+ &s3c24xx_dclk->dclk_lock);
+ clk_table[MUX_DCLK1] = clk_register_mux(&pdev->dev, "mux_dclk1",
+ dclk_variant->mux_parent_names,
+ dclk_variant->mux_num_parents, 0,
+ s3c24xx_dclk->base, 17, 1, 0,
+ &s3c24xx_dclk->dclk_lock);
+
+ clk_table[DIV_DCLK0] = clk_register_divider(&pdev->dev, "div_dclk0",
+ "mux_dclk0", 0, s3c24xx_dclk->base,
+ 4, 4, 0, &s3c24xx_dclk->dclk_lock);
+ clk_table[DIV_DCLK1] = clk_register_divider(&pdev->dev, "div_dclk1",
+ "mux_dclk1", 0, s3c24xx_dclk->base,
+ 20, 4, 0, &s3c24xx_dclk->dclk_lock);
+
+ clk_table[GATE_DCLK0] = clk_register_gate(&pdev->dev, "gate_dclk0",
+ "div_dclk0", CLK_SET_RATE_PARENT,
+ s3c24xx_dclk->base, 0, 0,
+ &s3c24xx_dclk->dclk_lock);
+ clk_table[GATE_DCLK1] = clk_register_gate(&pdev->dev, "gate_dclk1",
+ "div_dclk1", CLK_SET_RATE_PARENT,
+ s3c24xx_dclk->base, 16, 0,
+ &s3c24xx_dclk->dclk_lock);
+
+ clk_table[MUX_CLKOUT0] = s3c24xx_register_clkout(&pdev->dev,
+ "clkout0", dclk_variant->clkout0_parent_names,
+ dclk_variant->clkout0_num_parents, 4, 7);
+ clk_table[MUX_CLKOUT1] = s3c24xx_register_clkout(&pdev->dev,
+ "clkout1", dclk_variant->clkout1_parent_names,
+ dclk_variant->clkout1_num_parents, 8, 7);
+
+ for (i = 0; i < DCLK_MAX_CLKS; i++)
+ if (IS_ERR(clk_table[i])) {
+ dev_err(&pdev->dev, "clock %d failed to register\n", i);
+ ret = PTR_ERR(clk_table[i]);
+ goto err_clk_register;
+ }
+
+ ret = clk_register_clkdev(clk_table[MUX_DCLK0], "dclk0", NULL);
+ if (!ret)
+ ret = clk_register_clkdev(clk_table[MUX_DCLK1], "dclk1", NULL);
+ if (!ret)
+ ret = clk_register_clkdev(clk_table[MUX_CLKOUT0],
+ "clkout0", NULL);
+ if (!ret)
+ ret = clk_register_clkdev(clk_table[MUX_CLKOUT1],
+ "clkout1", NULL);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register aliases, %d\n", ret);
+ goto err_clk_register;
+ }
+
+ s3c24xx_dclk->dclk0_div_change_nb.notifier_call =
+ s3c24xx_dclk0_div_notify;
+
+ s3c24xx_dclk->dclk1_div_change_nb.notifier_call =
+ s3c24xx_dclk1_div_notify;
+
+ ret = clk_notifier_register(clk_table[DIV_DCLK0],
+ &s3c24xx_dclk->dclk0_div_change_nb);
+ if (ret)
+ goto err_clk_register;
+
+ ret = clk_notifier_register(clk_table[DIV_DCLK1],
+ &s3c24xx_dclk->dclk1_div_change_nb);
+ if (ret)
+ goto err_dclk_notify;
+
+ return 0;
+
+err_dclk_notify:
+ clk_notifier_unregister(clk_table[DIV_DCLK0],
+ &s3c24xx_dclk->dclk0_div_change_nb);
+err_clk_register:
+ for (i = 0; i < DCLK_MAX_CLKS; i++)
+ if (clk_table[i] && !IS_ERR(clk_table[i]))
+ clk_unregister(clk_table[i]);
+
+ return ret;
+}
+
+static int s3c24xx_dclk_remove(struct platform_device *pdev)
+{
+ struct s3c24xx_dclk *s3c24xx_dclk = platform_get_drvdata(pdev);
+ struct clk **clk_table = s3c24xx_dclk->clk_data.clks;
+ int i;
+
+ clk_notifier_unregister(clk_table[DIV_DCLK1],
+ &s3c24xx_dclk->dclk1_div_change_nb);
+ clk_notifier_unregister(clk_table[DIV_DCLK0],
+ &s3c24xx_dclk->dclk0_div_change_nb);
+
+ for (i = 0; i < DCLK_MAX_CLKS; i++)
+ clk_unregister(clk_table[i]);
+
+ return 0;
+}
+
+static struct s3c24xx_dclk_drv_data dclk_variants[] = {
+ [S3C2410] = {
+ .clkout0_parent_names = clkout0_s3c2410_p,
+ .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2410_p),
+ .clkout1_parent_names = clkout1_s3c2410_p,
+ .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2410_p),
+ .mux_parent_names = dclk_s3c2410_p,
+ .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
+ },
+ [S3C2412] = {
+ .clkout0_parent_names = clkout0_s3c2412_p,
+ .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2412_p),
+ .clkout1_parent_names = clkout1_s3c2412_p,
+ .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2412_p),
+ .mux_parent_names = dclk_s3c2410_p,
+ .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
+ },
+ [S3C2440] = {
+ .clkout0_parent_names = clkout0_s3c2440_p,
+ .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2440_p),
+ .clkout1_parent_names = clkout1_s3c2440_p,
+ .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2440_p),
+ .mux_parent_names = dclk_s3c2410_p,
+ .mux_num_parents = ARRAY_SIZE(dclk_s3c2410_p),
+ },
+ [S3C2443] = {
+ .clkout0_parent_names = clkout0_s3c2443_p,
+ .clkout0_num_parents = ARRAY_SIZE(clkout0_s3c2443_p),
+ .clkout1_parent_names = clkout1_s3c2443_p,
+ .clkout1_num_parents = ARRAY_SIZE(clkout1_s3c2443_p),
+ .mux_parent_names = dclk_s3c2443_p,
+ .mux_num_parents = ARRAY_SIZE(dclk_s3c2443_p),
+ },
+};
+
+static struct platform_device_id s3c24xx_dclk_driver_ids[] = {
+ {
+ .name = "s3c2410-dclk",
+ .driver_data = (kernel_ulong_t)&dclk_variants[S3C2410],
+ }, {
+ .name = "s3c2412-dclk",
+ .driver_data = (kernel_ulong_t)&dclk_variants[S3C2412],
+ }, {
+ .name = "s3c2440-dclk",
+ .driver_data = (kernel_ulong_t)&dclk_variants[S3C2440],
+ }, {
+ .name = "s3c2443-dclk",
+ .driver_data = (kernel_ulong_t)&dclk_variants[S3C2443],
+ },
+ { }
+};
+
+MODULE_DEVICE_TABLE(platform, s3c24xx_dclk_driver_ids);
+
+static struct platform_driver s3c24xx_dclk_driver = {
+ .driver = {
+ .name = "s3c24xx-dclk",
+ .owner = THIS_MODULE,
+ .pm = &s3c24xx_dclk_pm_ops,
+ },
+ .probe = s3c24xx_dclk_probe,
+ .remove = s3c24xx_dclk_remove,
+ .id_table = s3c24xx_dclk_driver_ids,
+};
+module_platform_driver(s3c24xx_dclk_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Heiko Stuebner <heiko at sntech.de>");
+MODULE_DESCRIPTION("Driver for the S3C24XX external clock outputs");
--
1.9.0
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