diff options
Diffstat (limited to 'drivers/clk/keystone/syscon-clk.c')
| -rw-r--r-- | drivers/clk/keystone/syscon-clk.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/drivers/clk/keystone/syscon-clk.c b/drivers/clk/keystone/syscon-clk.c new file mode 100644 index 000000000000..8d7dbea3bd30 --- /dev/null +++ b/drivers/clk/keystone/syscon-clk.c @@ -0,0 +1,172 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com/ + */ + +#include <linux/clk-provider.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +struct ti_syscon_gate_clk_priv { + struct clk_hw hw; + struct regmap *regmap; + u32 reg; + u32 idx; +}; + +struct ti_syscon_gate_clk_data { + char *name; + u32 offset; + u32 bit_idx; +}; + +static struct +ti_syscon_gate_clk_priv *to_ti_syscon_gate_clk_priv(struct clk_hw *hw) +{ + return container_of(hw, struct ti_syscon_gate_clk_priv, hw); +} + +static int ti_syscon_gate_clk_enable(struct clk_hw *hw) +{ + struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw); + + return regmap_write_bits(priv->regmap, priv->reg, priv->idx, + priv->idx); +} + +static void ti_syscon_gate_clk_disable(struct clk_hw *hw) +{ + struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw); + + regmap_write_bits(priv->regmap, priv->reg, priv->idx, 0); +} + +static int ti_syscon_gate_clk_is_enabled(struct clk_hw *hw) +{ + unsigned int val; + struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw); + + regmap_read(priv->regmap, priv->reg, &val); + + return !!(val & priv->idx); +} + +static const struct clk_ops ti_syscon_gate_clk_ops = { + .enable = ti_syscon_gate_clk_enable, + .disable = ti_syscon_gate_clk_disable, + .is_enabled = ti_syscon_gate_clk_is_enabled, +}; + +static struct clk_hw +*ti_syscon_gate_clk_register(struct device *dev, struct regmap *regmap, + const struct ti_syscon_gate_clk_data *data) +{ + struct ti_syscon_gate_clk_priv *priv; + struct clk_init_data init; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return ERR_PTR(-ENOMEM); + + init.name = data->name; + init.ops = &ti_syscon_gate_clk_ops; + init.parent_names = NULL; + init.num_parents = 0; + init.flags = 0; + + priv->regmap = regmap; + priv->reg = data->offset; + priv->idx = BIT(data->bit_idx); + priv->hw.init = &init; + + ret = devm_clk_hw_register(dev, &priv->hw); + if (ret) + return ERR_PTR(ret); + + return &priv->hw; +} + +static int ti_syscon_gate_clk_probe(struct platform_device *pdev) +{ + const struct ti_syscon_gate_clk_data *data, *p; + struct clk_hw_onecell_data *hw_data; + struct device *dev = &pdev->dev; + struct regmap *regmap; + int num_clks, i; + + data = device_get_match_data(dev); + if (!data) + return -EINVAL; + + regmap = syscon_node_to_regmap(dev->of_node); + if (IS_ERR(regmap)) { + if (PTR_ERR(regmap) == -EPROBE_DEFER) + return -EPROBE_DEFER; + dev_err(dev, "failed to find parent regmap\n"); + return PTR_ERR(regmap); + } + + num_clks = 0; + for (p = data; p->name; p++) + num_clks++; + + hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, num_clks), + GFP_KERNEL); + if (!hw_data) + return -ENOMEM; + + hw_data->num = num_clks; + + for (i = 0; i < num_clks; i++) { + hw_data->hws[i] = ti_syscon_gate_clk_register(dev, regmap, + &data[i]); + if (IS_ERR(hw_data->hws[i])) + dev_warn(dev, "failed to register %s\n", + data[i].name); + } + + return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, + hw_data); +} + +#define TI_SYSCON_CLK_GATE(_name, _offset, _bit_idx) \ + { \ + .name = _name, \ + .offset = (_offset), \ + .bit_idx = (_bit_idx), \ + } + +static const struct ti_syscon_gate_clk_data am654_clk_data[] = { + TI_SYSCON_CLK_GATE("ehrpwm_tbclk0", 0x0, 0), + TI_SYSCON_CLK_GATE("ehrpwm_tbclk1", 0x4, 0), + TI_SYSCON_CLK_GATE("ehrpwm_tbclk2", 0x8, 0), + TI_SYSCON_CLK_GATE("ehrpwm_tbclk3", 0xc, 0), + TI_SYSCON_CLK_GATE("ehrpwm_tbclk4", 0x10, 0), + TI_SYSCON_CLK_GATE("ehrpwm_tbclk5", 0x14, 0), + { /* Sentinel */ }, +}; + +static const struct of_device_id ti_syscon_gate_clk_ids[] = { + { + .compatible = "ti,am654-ehrpwm-tbclk", + .data = &am654_clk_data, + }, + { } +}; +MODULE_DEVICE_TABLE(of, ti_syscon_gate_clk_ids); + +static struct platform_driver ti_syscon_gate_clk_driver = { + .probe = ti_syscon_gate_clk_probe, + .driver = { + .name = "ti-syscon-gate-clk", + .of_match_table = ti_syscon_gate_clk_ids, + }, +}; +module_platform_driver(ti_syscon_gate_clk_driver); + +MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>"); +MODULE_DESCRIPTION("Syscon backed gate-clock driver"); +MODULE_LICENSE("GPL"); |