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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/clk/clk-gate.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'drivers/clk/clk-gate.c')
| -rw-r--r-- | drivers/clk/clk-gate.c | 259 |
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c new file mode 100644 index 000000000..44f5e0c53 --- /dev/null +++ b/drivers/clk/clk-gate.c @@ -0,0 +1,259 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com> + * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org> + * + * Gated clock implementation + */ + +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/string.h> + +/** + * DOC: basic gateable clock which can gate and ungate its output + * + * Traits of this clock: + * prepare - clk_(un)prepare only ensures parent is (un)prepared + * enable - clk_enable and clk_disable are functional & control gating + * rate - inherits rate from parent. No clk_set_rate support + * parent - fixed parent. No clk_set_parent support + */ + +static inline u32 clk_gate_readl(struct clk_gate *gate) +{ + if (gate->flags & CLK_GATE_BIG_ENDIAN) + return ioread32be(gate->reg); + + return readl(gate->reg); +} + +static inline void clk_gate_writel(struct clk_gate *gate, u32 val) +{ + if (gate->flags & CLK_GATE_BIG_ENDIAN) + iowrite32be(val, gate->reg); + else + writel(val, gate->reg); +} + +/* + * It works on following logic: + * + * For enabling clock, enable = 1 + * set2dis = 1 -> clear bit -> set = 0 + * set2dis = 0 -> set bit -> set = 1 + * + * For disabling clock, enable = 0 + * set2dis = 1 -> set bit -> set = 1 + * set2dis = 0 -> clear bit -> set = 0 + * + * So, result is always: enable xor set2dis. + */ +static void clk_gate_endisable(struct clk_hw *hw, int enable) +{ + struct clk_gate *gate = to_clk_gate(hw); + int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0; + unsigned long flags; + u32 reg; + + set ^= enable; + + if (gate->lock) + spin_lock_irqsave(gate->lock, flags); + else + __acquire(gate->lock); + + if (gate->flags & CLK_GATE_HIWORD_MASK) { + reg = BIT(gate->bit_idx + 16); + if (set) + reg |= BIT(gate->bit_idx); + } else { + reg = clk_gate_readl(gate); + + if (set) + reg |= BIT(gate->bit_idx); + else + reg &= ~BIT(gate->bit_idx); + } + + clk_gate_writel(gate, reg); + + if (gate->lock) + spin_unlock_irqrestore(gate->lock, flags); + else + __release(gate->lock); +} + +static int clk_gate_enable(struct clk_hw *hw) +{ + clk_gate_endisable(hw, 1); + + return 0; +} + +static void clk_gate_disable(struct clk_hw *hw) +{ + clk_gate_endisable(hw, 0); +} + +int clk_gate_is_enabled(struct clk_hw *hw) +{ + u32 reg; + struct clk_gate *gate = to_clk_gate(hw); + + reg = clk_gate_readl(gate); + + /* if a set bit disables this clk, flip it before masking */ + if (gate->flags & CLK_GATE_SET_TO_DISABLE) + reg ^= BIT(gate->bit_idx); + + reg &= BIT(gate->bit_idx); + + return reg ? 1 : 0; +} +EXPORT_SYMBOL_GPL(clk_gate_is_enabled); + +const struct clk_ops clk_gate_ops = { + .enable = clk_gate_enable, + .disable = clk_gate_disable, + .is_enabled = clk_gate_is_enabled, +}; +EXPORT_SYMBOL_GPL(clk_gate_ops); + +struct clk_hw *__clk_hw_register_gate(struct device *dev, + struct device_node *np, const char *name, + const char *parent_name, const struct clk_hw *parent_hw, + const struct clk_parent_data *parent_data, + unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct clk_gate *gate; + struct clk_hw *hw; + struct clk_init_data init = {}; + int ret = -EINVAL; + + if (clk_gate_flags & CLK_GATE_HIWORD_MASK) { + if (bit_idx > 15) { + pr_err("gate bit exceeds LOWORD field\n"); + return ERR_PTR(-EINVAL); + } + } + + /* allocate the gate */ + gate = kzalloc_obj(*gate); + if (!gate) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &clk_gate_ops; + init.flags = flags; + init.parent_names = parent_name ? &parent_name : NULL; + init.parent_hws = parent_hw ? &parent_hw : NULL; + init.parent_data = parent_data; + if (parent_name || parent_hw || parent_data) + init.num_parents = 1; + else + init.num_parents = 0; + + /* struct clk_gate assignments */ + gate->reg = reg; + gate->bit_idx = bit_idx; + gate->flags = clk_gate_flags; + gate->lock = lock; + gate->hw.init = &init; + + hw = &gate->hw; + if (dev || !np) + ret = clk_hw_register(dev, hw); + else if (np) + ret = of_clk_hw_register(np, hw); + if (ret) { + kfree(gate); + hw = ERR_PTR(ret); + } + + return hw; + +} +EXPORT_SYMBOL_GPL(__clk_hw_register_gate); + +struct clk *clk_register_gate(struct device *dev, const char *name, + const char *parent_name, unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct clk_hw *hw; + + hw = clk_hw_register_gate(dev, name, parent_name, flags, reg, + bit_idx, clk_gate_flags, lock); + if (IS_ERR(hw)) + return ERR_CAST(hw); + return hw->clk; +} +EXPORT_SYMBOL_GPL(clk_register_gate); + +void clk_unregister_gate(struct clk *clk) +{ + struct clk_gate *gate; + struct clk_hw *hw; + + hw = __clk_get_hw(clk); + if (!hw) + return; + + gate = to_clk_gate(hw); + + clk_unregister(clk); + kfree(gate); +} +EXPORT_SYMBOL_GPL(clk_unregister_gate); + +void clk_hw_unregister_gate(struct clk_hw *hw) +{ + struct clk_gate *gate; + + gate = to_clk_gate(hw); + + clk_hw_unregister(hw); + kfree(gate); +} +EXPORT_SYMBOL_GPL(clk_hw_unregister_gate); + +static void devm_clk_hw_release_gate(struct device *dev, void *res) +{ + clk_hw_unregister_gate(*(struct clk_hw **)res); +} + +struct clk_hw *__devm_clk_hw_register_gate(struct device *dev, + struct device_node *np, const char *name, + const char *parent_name, const struct clk_hw *parent_hw, + const struct clk_parent_data *parent_data, + unsigned long flags, + void __iomem *reg, u8 bit_idx, + u8 clk_gate_flags, spinlock_t *lock) +{ + struct clk_hw **ptr, *hw; + + ptr = devres_alloc(devm_clk_hw_release_gate, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + hw = __clk_hw_register_gate(dev, np, name, parent_name, parent_hw, + parent_data, flags, reg, bit_idx, + clk_gate_flags, lock); + + if (!IS_ERR(hw)) { + *ptr = hw; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return hw; +} +EXPORT_SYMBOL_GPL(__devm_clk_hw_register_gate); |
