[PATCH 5/7] clk: sunxi: add PRCM (Power/Reset/Clock Management) clks support
Boris BREZILLON
boris.brezillon at free-electrons.com
Mon Apr 28 07:58:48 PDT 2014
The PRCM (Power/Reset/Clock Management) unit provides several clock
devices:
- AR100 clk: used to clock the Power Management co-processor
- AHB0 clk: used to clock the AHB0 bus
- APB0 clk and gates: used to clk
Add support for these clks in a separate driver so that they can be probed
as platform devices instead of registered during early init.
We need this to be able to probe PRCM MFD subdevices.
Signed-off-by: Boris BREZILLON <boris.brezillon at free-electrons.com>
---
drivers/clk/sunxi/Makefile | 2 +
drivers/clk/sunxi/clk-sun6i-prcm.c | 253 +++++++++++++++++++++++++++++++++++++
2 files changed, 255 insertions(+)
create mode 100644 drivers/clk/sunxi/clk-sun6i-prcm.c
diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
index b5bac91..ef8cdc9 100644
--- a/drivers/clk/sunxi/Makefile
+++ b/drivers/clk/sunxi/Makefile
@@ -3,3 +3,5 @@
#
obj-y += clk-sunxi.o clk-factors.o
+
+obj-$(CONFIG_MFD_SUN6I_PRCM) += clk-sun6i-prcm.o
diff --git a/drivers/clk/sunxi/clk-sun6i-prcm.c b/drivers/clk/sunxi/clk-sun6i-prcm.c
new file mode 100644
index 0000000..bb7b25a
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun6i-prcm.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright (C) 2014 Free Electrons
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Boris BREZILLON <boris.brezillon at free-electrons.com>
+ *
+ * Allwinner PRCM (Power/Reset/Clock Management) driver
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#define SUN6I_APB0_GATES_MAX_SIZE 32
+#define SUN6I_AR100_MAX_PARENTS 4
+
+static int sun6i_a31_ar100_mux_clk_register(struct platform_device *pdev)
+{
+ const char *parents[SUN6I_AR100_MAX_PARENTS];
+ struct device_node *np = pdev->dev.of_node;
+ const char *clk_name = np->name;
+ struct resource *r;
+ void __iomem *reg;
+ struct clk *clk;
+ int nparents;
+ int i;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ nparents = of_clk_get_parent_count(np);
+ if (nparents > SUN6I_AR100_MAX_PARENTS)
+ nparents = SUN6I_AR100_MAX_PARENTS;
+
+ for (i = 0; i < nparents; i++)
+ parents[i] = of_clk_get_parent_name(np, i);
+
+ of_property_read_string(np, "clock-output-names", &clk_name);
+
+ clk = clk_register_mux(&pdev->dev, clk_name, parents, nparents,
+ CLK_SET_RATE_NO_REPARENT, reg,
+ 16, 2, 0, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+
+static int sun6i_a31_ar100_clk_register(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const char *clk_name = np->name;
+ const char *clk_parent;
+ struct resource *r;
+ void __iomem *reg;
+ struct clk *clk;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ clk_parent = of_clk_get_parent_name(np, 0);
+ if (!clk_parent)
+ return -EINVAL;
+
+ of_property_read_string(np, "clock-output-names", &clk_name);
+
+ clk = clk_register_divider(&pdev->dev, clk_name, clk_parent,
+ 0, reg, 4, 2, CLK_DIVIDER_POWER_OF_TWO,
+ NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+
+static int sun6i_a31_ar100_div_clk_register(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const char *clk_name = np->name;
+ const char *clk_parent;
+ struct resource *r;
+ void __iomem *reg;
+ struct clk *clk;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ clk_parent = of_clk_get_parent_name(np, 0);
+ if (!clk_parent)
+ return -EINVAL;
+
+ of_property_read_string(np, "clock-output-names", &clk_name);
+
+ clk = clk_register_divider(&pdev->dev, clk_name, clk_parent,
+ 0, reg, 8, 5, 0, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+
+static int sun6i_a31_apb0_clk_register(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ const char *clk_name = np->name;
+ const char *clk_parent;
+ struct resource *r;
+ void __iomem *reg;
+ struct clk *clk;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ clk_parent = of_clk_get_parent_name(np, 0);
+ if (!clk_parent)
+ return -EINVAL;
+
+ of_property_read_string(np, "clock-output-names", &clk_name);
+
+ clk = clk_register_divider(&pdev->dev, clk_name, clk_parent,
+ 0, reg, 0, 2, CLK_DIVIDER_POWER_OF_TWO,
+ NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
+
+static int sun6i_a31_apb0_gates_clk_register(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct clk_onecell_data *clk_data;
+ const char *clk_parent;
+ const char *clk_name;
+ struct resource *r;
+ void __iomem *reg;
+ int gate_id;
+ int ngates;
+ int i;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap_resource(&pdev->dev, r);
+ if (!reg)
+ return PTR_ERR(reg);
+
+ clk_parent = of_clk_get_parent_name(np, 0);
+ if (!clk_parent)
+ return -EINVAL;
+
+ ngates = of_property_count_strings(np, "clock-output-names");
+ if (ngates < 0)
+ return ngates;
+
+ if (!ngates || ngates > SUN6I_APB0_GATES_MAX_SIZE)
+ return -EINVAL;
+
+ clk_data = devm_kzalloc(&pdev->dev, sizeof(struct clk_onecell_data),
+ GFP_KERNEL);
+ if (!clk_data)
+ return -ENOMEM;
+
+ clk_data->clks = devm_kzalloc(&pdev->dev,
+ SUN6I_APB0_GATES_MAX_SIZE *
+ sizeof(struct clk *),
+ GFP_KERNEL);
+ if (!clk_data->clks)
+ return -ENOMEM;
+
+ for (i = 0; i < ngates; i++) {
+ of_property_read_string_index(np, "clock-output-names",
+ i, &clk_name);
+
+ gate_id = i;
+ of_property_read_u32_index(np, "clock-indices", i, &gate_id);
+
+ WARN_ON(gate_id >= SUN6I_APB0_GATES_MAX_SIZE);
+ if (gate_id >= SUN6I_APB0_GATES_MAX_SIZE)
+ continue;
+
+ clk_data->clks[gate_id] = clk_register_gate(&pdev->dev,
+ clk_name,
+ clk_parent, 0,
+ reg, gate_id,
+ 0, NULL);
+ WARN_ON(IS_ERR(clk_data->clks[gate_id]));
+ }
+
+ clk_data->clk_num = ngates;
+
+ return of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
+}
+
+const struct of_device_id sun6i_a31_prcm_clk_dt_ids[] = {
+ {
+ .compatible = "allwinner,sun6i-a31-ar100-mux-clk",
+ .data = sun6i_a31_ar100_mux_clk_register,
+ },
+ {
+ .compatible = "allwinner,sun6i-a31-ar100-clk",
+ .data = sun6i_a31_ar100_clk_register,
+ },
+ {
+ .compatible = "allwinner,sun6i-a31-ar100-div-clk",
+ .data = sun6i_a31_ar100_div_clk_register,
+ },
+ {
+ .compatible = "allwinner,sun6i-a31-apb0-clk",
+ .data = sun6i_a31_apb0_clk_register,
+ },
+ {
+ .compatible = "allwinner,sun6i-a31-apb0-gates-clk",
+ .data = sun6i_a31_apb0_gates_clk_register,
+ },
+ { /* sentinel */ }
+};
+
+static int sun6i_a31_prcm_clk_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ int (*register_func)(struct platform_device *pdev);
+ const struct of_device_id *match;
+
+ match = of_match_node(sun6i_a31_prcm_clk_dt_ids, np);
+ if (!match)
+ return -EINVAL;
+
+ register_func = match->data;
+ return register_func(pdev);
+}
+
+static struct platform_driver sun6i_a31_prcm_clk_driver = {
+ .driver = {
+ .name = "sun6i-a31-prcm-clk",
+ .owner = THIS_MODULE,
+ .of_match_table = sun6i_a31_prcm_clk_dt_ids,
+ },
+ .probe = sun6i_a31_prcm_clk_probe,
+};
+module_platform_driver(sun6i_a31_prcm_clk_driver);
+
+MODULE_AUTHOR("Boris BREZILLON <boris.brezillon at free-electrons.com");
+MODULE_DESCRIPTION("Allwinner Reset Controller Driver");
+MODULE_LICENSE("GPL v2");
--
1.8.3.2
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