diff options
Diffstat (limited to 'kernel/drivers/clk/tegra/clk-pll-out.c')
-rw-r--r-- | kernel/drivers/clk/tegra/clk-pll-out.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/kernel/drivers/clk/tegra/clk-pll-out.c b/kernel/drivers/clk/tegra/clk-pll-out.c new file mode 100644 index 000000000..3598987a4 --- /dev/null +++ b/kernel/drivers/clk/tegra/clk-pll-out.c @@ -0,0 +1,123 @@ +/* + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/err.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/clk-provider.h> +#include <linux/clk.h> + +#include "clk.h" + +#define pll_out_enb(p) (BIT(p->enb_bit_idx)) +#define pll_out_rst(p) (BIT(p->rst_bit_idx)) + +static int clk_pll_out_is_enabled(struct clk_hw *hw) +{ + struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw); + u32 val = readl_relaxed(pll_out->reg); + int state; + + state = (val & pll_out_enb(pll_out)) ? 1 : 0; + if (!(val & (pll_out_rst(pll_out)))) + state = 0; + return state; +} + +static int clk_pll_out_enable(struct clk_hw *hw) +{ + struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw); + unsigned long flags = 0; + u32 val; + + if (pll_out->lock) + spin_lock_irqsave(pll_out->lock, flags); + + val = readl_relaxed(pll_out->reg); + + val |= (pll_out_enb(pll_out) | pll_out_rst(pll_out)); + + writel_relaxed(val, pll_out->reg); + udelay(2); + + if (pll_out->lock) + spin_unlock_irqrestore(pll_out->lock, flags); + + return 0; +} + +static void clk_pll_out_disable(struct clk_hw *hw) +{ + struct tegra_clk_pll_out *pll_out = to_clk_pll_out(hw); + unsigned long flags = 0; + u32 val; + + if (pll_out->lock) + spin_lock_irqsave(pll_out->lock, flags); + + val = readl_relaxed(pll_out->reg); + + val &= ~(pll_out_enb(pll_out) | pll_out_rst(pll_out)); + + writel_relaxed(val, pll_out->reg); + udelay(2); + + if (pll_out->lock) + spin_unlock_irqrestore(pll_out->lock, flags); +} + +const struct clk_ops tegra_clk_pll_out_ops = { + .is_enabled = clk_pll_out_is_enabled, + .enable = clk_pll_out_enable, + .disable = clk_pll_out_disable, +}; + +struct clk *tegra_clk_register_pll_out(const char *name, + const char *parent_name, void __iomem *reg, u8 enb_bit_idx, + u8 rst_bit_idx, unsigned long flags, u8 pll_out_flags, + spinlock_t *lock) +{ + struct tegra_clk_pll_out *pll_out; + struct clk *clk; + struct clk_init_data init; + + pll_out = kzalloc(sizeof(*pll_out), GFP_KERNEL); + if (!pll_out) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.ops = &tegra_clk_pll_out_ops; + init.parent_names = (parent_name ? &parent_name : NULL); + init.num_parents = (parent_name ? 1 : 0); + init.flags = flags; + + pll_out->reg = reg; + pll_out->enb_bit_idx = enb_bit_idx; + pll_out->rst_bit_idx = rst_bit_idx; + pll_out->flags = pll_out_flags; + pll_out->lock = lock; + + /* Data in .init is copied by clk_register(), so stack variable OK */ + pll_out->hw.init = &init; + + clk = clk_register(NULL, &pll_out->hw); + if (IS_ERR(clk)) + kfree(pll_out); + + return clk; +} |