diff options
Diffstat (limited to 'drivers/clk/sunxi-ng/ccu_frac.c')
-rw-r--r-- | drivers/clk/sunxi-ng/ccu_frac.c | 112 |
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_frac.c b/drivers/clk/sunxi-ng/ccu_frac.c new file mode 100644 index 000000000..d1d168d4c --- /dev/null +++ b/drivers/clk/sunxi-ng/ccu_frac.c @@ -0,0 +1,112 @@ +/* + * Copyright (C) 2016 Maxime Ripard + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * 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. + */ + +#include <linux/clk-provider.h> +#include <linux/spinlock.h> + +#include "ccu_frac.h" + +bool ccu_frac_helper_is_enabled(struct ccu_common *common, + struct ccu_frac_internal *cf) +{ + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return false; + + return !(readl(common->base + common->reg) & cf->enable); +} + +void ccu_frac_helper_enable(struct ccu_common *common, + struct ccu_frac_internal *cf) +{ + unsigned long flags; + u32 reg; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + writel(reg & ~cf->enable, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); +} + +void ccu_frac_helper_disable(struct ccu_common *common, + struct ccu_frac_internal *cf) +{ + unsigned long flags; + u32 reg; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + writel(reg | cf->enable, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); +} + +bool ccu_frac_helper_has_rate(struct ccu_common *common, + struct ccu_frac_internal *cf, + unsigned long rate) +{ + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return false; + + return (cf->rates[0] == rate) || (cf->rates[1] == rate); +} + +unsigned long ccu_frac_helper_read_rate(struct ccu_common *common, + struct ccu_frac_internal *cf) +{ + u32 reg; + + pr_debug("%s: Read fractional\n", clk_hw_get_name(&common->hw)); + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return 0; + + pr_debug("%s: clock is fractional (rates %lu and %lu)\n", + clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]); + + reg = readl(common->base + common->reg); + + pr_debug("%s: clock reg is 0x%x (select is 0x%x)\n", + clk_hw_get_name(&common->hw), reg, cf->select); + + return (reg & cf->select) ? cf->rates[1] : cf->rates[0]; +} + +int ccu_frac_helper_set_rate(struct ccu_common *common, + struct ccu_frac_internal *cf, + unsigned long rate, u32 lock) +{ + unsigned long flags; + u32 reg, sel; + + if (!(common->features & CCU_FEATURE_FRACTIONAL)) + return -EINVAL; + + if (cf->rates[0] == rate) + sel = 0; + else if (cf->rates[1] == rate) + sel = cf->select; + else + return -EINVAL; + + spin_lock_irqsave(common->lock, flags); + reg = readl(common->base + common->reg); + reg &= ~cf->select; + writel(reg | sel, common->base + common->reg); + spin_unlock_irqrestore(common->lock, flags); + + ccu_helper_wait_for_lock(common, lock); + + return 0; +} |