diff options
Diffstat (limited to 'drivers/clk/at91/clk-system.c')
| -rw-r--r-- | drivers/clk/at91/clk-system.c | 74 |
1 files changed, 64 insertions, 10 deletions
diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c index 48c89fe0cfe8..8c96307d7363 100644 --- a/drivers/clk/at91/clk-system.c +++ b/drivers/clk/at91/clk-system.c @@ -14,6 +14,11 @@ #include <linux/of.h> #include <linux/of_address.h> #include <linux/io.h> +#include <linux/irq.h> +#include <linux/of_irq.h> +#include <linux/interrupt.h> +#include <linux/wait.h> +#include <linux/sched.h> #include "pmc.h" @@ -25,19 +30,48 @@ struct clk_system { struct clk_hw hw; struct at91_pmc *pmc; + unsigned int irq; + wait_queue_head_t wait; u8 id; }; -static int clk_system_enable(struct clk_hw *hw) +static inline int is_pck(int id) +{ + return (id >= 8) && (id <= 15); +} +static irqreturn_t clk_system_irq_handler(int irq, void *dev_id) +{ + struct clk_system *sys = (struct clk_system *)dev_id; + + wake_up(&sys->wait); + disable_irq_nosync(sys->irq); + + return IRQ_HANDLED; +} + +static int clk_system_prepare(struct clk_hw *hw) { struct clk_system *sys = to_clk_system(hw); struct at91_pmc *pmc = sys->pmc; + u32 mask = 1 << sys->id; - pmc_write(pmc, AT91_PMC_SCER, 1 << sys->id); + pmc_write(pmc, AT91_PMC_SCER, mask); + + if (!is_pck(sys->id)) + return 0; + + while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) { + if (sys->irq) { + enable_irq(sys->irq); + wait_event(sys->wait, + pmc_read(pmc, AT91_PMC_SR) & mask); + } else + cpu_relax(); + } return 0; } -static void clk_system_disable(struct clk_hw *hw) +static void clk_system_unprepare(struct clk_hw *hw) { struct clk_system *sys = to_clk_system(hw); struct at91_pmc *pmc = sys->pmc; @@ -45,27 +79,34 @@ static void clk_system_disable(struct clk_hw *hw) pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id); } -static int clk_system_is_enabled(struct clk_hw *hw) +static int clk_system_is_prepared(struct clk_hw *hw) { struct clk_system *sys = to_clk_system(hw); struct at91_pmc *pmc = sys->pmc; - return !!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)); + if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id))) + return 0; + + if (!is_pck(sys->id)) + return 1; + + return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id)); } static const struct clk_ops system_ops = { - .enable = clk_system_enable, - .disable = clk_system_disable, - .is_enabled = clk_system_is_enabled, + .prepare = clk_system_prepare, + .unprepare = clk_system_unprepare, + .is_prepared = clk_system_is_prepared, }; static struct clk * __init at91_clk_register_system(struct at91_pmc *pmc, const char *name, - const char *parent_name, u8 id) + const char *parent_name, u8 id, int irq) { struct clk_system *sys; struct clk *clk = NULL; struct clk_init_data init; + int ret; if (!parent_name || id > SYSTEM_MAX_ID) return ERR_PTR(-EINVAL); @@ -89,6 +130,15 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name, sys->id = id; sys->hw.init = &init; sys->pmc = pmc; + sys->irq = irq; + if (irq) { + init_waitqueue_head(&sys->wait); + irq_set_status_flags(sys->irq, IRQ_NOAUTOEN); + ret = request_irq(sys->irq, clk_system_irq_handler, + IRQF_TRIGGER_HIGH, name, sys); + if (ret) + return ERR_PTR(ret); + } clk = clk_register(NULL, &sys->hw); if (IS_ERR(clk)) @@ -101,6 +151,7 @@ static void __init of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc) { int num; + int irq = 0; u32 id; struct clk *clk; const char *name; @@ -118,9 +169,12 @@ of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc) if (of_property_read_string(np, "clock-output-names", &name)) name = sysclknp->name; + if (is_pck(id)) + irq = irq_of_parse_and_map(sysclknp, 0); + parent_name = of_clk_get_parent_name(sysclknp, 0); - clk = at91_clk_register_system(pmc, name, parent_name, id); + clk = at91_clk_register_system(pmc, name, parent_name, id, irq); if (IS_ERR(clk)) continue; |