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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-21 12:30:30 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-21 12:30:30 -0800
commit18a8d49973667aa016e68826eeb374788b7c63b0 (patch)
treed7f90fcf05087ce50ee931b596e60e4c3c082a29 /drivers/clk/sunxi/clk-sun9i-mmc.c
parentc189cb8ef62832f33b6cf757350a0270532a1ad8 (diff)
parentec02ace8ca0a50eef430d3676de5c5fa978b0e29 (diff)
Merge tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux
Pull clock framework updates from Mike Turquette: "The clock framework changes contain the usual driver additions, enhancements and fixes mostly for ARM32, ARM64, MIPS and Power-based devices. Additionally the framework core underwent a bit of surgery with two major changes: - The boundary between the clock core and clock providers (e.g clock drivers) is now more well defined with dedicated provider helper functions. struct clk no longer maps 1:1 with the hardware clock but is a true per-user cookie which helps us tracker users of hardware clocks and debug bad behavior. - The addition of rate constraints for clocks. Rate ranges are now supported which are analogous to the voltage ranges in the regulator framework. Unfortunately these changes to the core created some breakeage. We think we fixed it all up but for this reason there are lots of last minute commits trying to undo the damage" * tag 'clk-for-linus-3.20' of git://git.linaro.org/people/mike.turquette/linux: (113 commits) clk: Only recalculate the rate if needed Revert "clk: mxs: Fix invalid 32-bit access to frac registers" clk: qoriq: Add support for the platform PLL powerpc/corenet: Enable CLK_QORIQ clk: Replace explicit clk assignment with __clk_hw_set_clk clk: Add __clk_hw_set_clk helper function clk: Don't dereference parent clock if is NULL MIPS: Alchemy: Remove bogus args from alchemy_clk_fgcs_detr clkdev: Always allocate a struct clk and call __clk_get() w/ CCF clk: shmobile: div6: Avoid division by zero in .round_rate() clk: mxs: Fix invalid 32-bit access to frac registers clk: omap: compile legacy omap3 clocks conditionally clkdev: Export clk_register_clkdev clk: Add rate constraints to clocks clk: remove clk-private.h pci: xgene: do not use clk-private.h arm: omap2+ remove dead clock code clk: Make clk API return per-user struct clk instances clk: tegra: Define PLLD_DSI and remove dsia(b)_mux clk: tegra: Add support for the Tegra132 CAR IP block ...
Diffstat (limited to 'drivers/clk/sunxi/clk-sun9i-mmc.c')
-rw-r--r--drivers/clk/sunxi/clk-sun9i-mmc.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sun9i-mmc.c b/drivers/clk/sunxi/clk-sun9i-mmc.c
new file mode 100644
index 000000000000..710c273648d7
--- /dev/null
+++ b/drivers/clk/sunxi/clk-sun9i-mmc.c
@@ -0,0 +1,219 @@
+/*
+ * Copyright 2015 Chen-Yu Tsai
+ *
+ * Chen-Yu Tsai <wens@csie.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/spinlock.h>
+
+#define SUN9I_MMC_WIDTH 4
+
+#define SUN9I_MMC_GATE_BIT 16
+#define SUN9I_MMC_RESET_BIT 18
+
+struct sun9i_mmc_clk_data {
+ spinlock_t lock;
+ void __iomem *membase;
+ struct clk *clk;
+ struct reset_control *reset;
+ struct clk_onecell_data clk_data;
+ struct reset_controller_dev rcdev;
+};
+
+static int sun9i_mmc_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct sun9i_mmc_clk_data *data = container_of(rcdev,
+ struct sun9i_mmc_clk_data,
+ rcdev);
+ unsigned long flags;
+ void __iomem *reg = data->membase + SUN9I_MMC_WIDTH * id;
+ u32 val;
+
+ clk_prepare_enable(data->clk);
+ spin_lock_irqsave(&data->lock, flags);
+
+ val = readl(reg);
+ writel(val & ~BIT(SUN9I_MMC_RESET_BIT), reg);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+ clk_disable_unprepare(data->clk);
+
+ return 0;
+}
+
+static int sun9i_mmc_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct sun9i_mmc_clk_data *data = container_of(rcdev,
+ struct sun9i_mmc_clk_data,
+ rcdev);
+ unsigned long flags;
+ void __iomem *reg = data->membase + SUN9I_MMC_WIDTH * id;
+ u32 val;
+
+ clk_prepare_enable(data->clk);
+ spin_lock_irqsave(&data->lock, flags);
+
+ val = readl(reg);
+ writel(val | BIT(SUN9I_MMC_RESET_BIT), reg);
+
+ spin_unlock_irqrestore(&data->lock, flags);
+ clk_disable_unprepare(data->clk);
+
+ return 0;
+}
+
+static struct reset_control_ops sun9i_mmc_reset_ops = {
+ .assert = sun9i_mmc_reset_assert,
+ .deassert = sun9i_mmc_reset_deassert,
+};
+
+static int sun9i_a80_mmc_config_clk_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct sun9i_mmc_clk_data *data;
+ struct clk_onecell_data *clk_data;
+ const char *clk_name = np->name;
+ const char *clk_parent;
+ struct resource *r;
+ int count, i, ret;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ spin_lock_init(&data->lock);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ /* one clock/reset pair per word */
+ count = DIV_ROUND_UP((r->end - r->start + 1), SUN9I_MMC_WIDTH);
+ data->membase = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(data->membase))
+ return PTR_ERR(data->membase);
+
+ clk_data = &data->clk_data;
+ clk_data->clk_num = count;
+ clk_data->clks = devm_kcalloc(&pdev->dev, count, sizeof(struct clk *),
+ GFP_KERNEL);
+ if (!clk_data->clks)
+ return -ENOMEM;
+
+ data->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(data->clk)) {
+ dev_err(&pdev->dev, "Could not get clock\n");
+ return PTR_ERR(data->clk);
+ }
+
+ data->reset = devm_reset_control_get(&pdev->dev, NULL);
+ if (IS_ERR(data->reset)) {
+ dev_err(&pdev->dev, "Could not get reset control\n");
+ return PTR_ERR(data->reset);
+ }
+
+ ret = reset_control_deassert(data->reset);
+ if (ret) {
+ dev_err(&pdev->dev, "Reset deassert err %d\n", ret);
+ return ret;
+ }
+
+ clk_parent = __clk_get_name(data->clk);
+ for (i = 0; i < count; i++) {
+ of_property_read_string_index(np, "clock-output-names",
+ i, &clk_name);
+
+ clk_data->clks[i] = clk_register_gate(&pdev->dev, clk_name,
+ clk_parent, 0,
+ data->membase + SUN9I_MMC_WIDTH * i,
+ SUN9I_MMC_GATE_BIT, 0,
+ &data->lock);
+
+ if (IS_ERR(clk_data->clks[i])) {
+ ret = PTR_ERR(clk_data->clks[i]);
+ goto err_clk_register;
+ }
+ }
+
+ ret = of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
+ if (ret)
+ goto err_clk_provider;
+
+ data->rcdev.owner = THIS_MODULE;
+ data->rcdev.nr_resets = count;
+ data->rcdev.ops = &sun9i_mmc_reset_ops;
+ data->rcdev.of_node = pdev->dev.of_node;
+
+ ret = reset_controller_register(&data->rcdev);
+ if (ret)
+ goto err_rc_reg;
+
+ platform_set_drvdata(pdev, data);
+
+ return 0;
+
+err_rc_reg:
+ of_clk_del_provider(np);
+
+err_clk_provider:
+ for (i = 0; i < count; i++)
+ clk_unregister(clk_data->clks[i]);
+
+err_clk_register:
+ reset_control_assert(data->reset);
+
+ return ret;
+}
+
+static int sun9i_a80_mmc_config_clk_remove(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct sun9i_mmc_clk_data *data = platform_get_drvdata(pdev);
+ struct clk_onecell_data *clk_data = &data->clk_data;
+ int i;
+
+ reset_controller_unregister(&data->rcdev);
+ of_clk_del_provider(np);
+ for (i = 0; i < clk_data->clk_num; i++)
+ clk_unregister(clk_data->clks[i]);
+
+ reset_control_assert(data->reset);
+
+ return 0;
+}
+
+static const struct of_device_id sun9i_a80_mmc_config_clk_dt_ids[] = {
+ { .compatible = "allwinner,sun9i-a80-mmc-config-clk" },
+ { /* sentinel */ }
+};
+
+static struct platform_driver sun9i_a80_mmc_config_clk_driver = {
+ .driver = {
+ .name = "sun9i-a80-mmc-config-clk",
+ .of_match_table = sun9i_a80_mmc_config_clk_dt_ids,
+ },
+ .probe = sun9i_a80_mmc_config_clk_probe,
+ .remove = sun9i_a80_mmc_config_clk_remove,
+};
+module_platform_driver(sun9i_a80_mmc_config_clk_driver);
+
+MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>");
+MODULE_DESCRIPTION("Allwinner A80 MMC clock/reset Driver");
+MODULE_LICENSE("GPL v2");