linux/drivers/clk/mmp/reset.c

100 lines
2.2 KiB
C

#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/reset-controller.h>
#include "reset.h"
#define rcdev_to_unit(rcdev) container_of(rcdev, struct mmp_clk_reset_unit, rcdev)
static int mmp_of_reset_xlate(struct reset_controller_dev *rcdev,
const struct of_phandle_args *reset_spec)
{
struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
struct mmp_clk_reset_cell *cell;
int i;
if (WARN_ON(reset_spec->args_count != rcdev->of_reset_n_cells))
return -EINVAL;
for (i = 0; i < rcdev->nr_resets; i++) {
cell = &unit->cells[i];
if (cell->clk_id == reset_spec->args[0])
break;
}
if (i == rcdev->nr_resets)
return -EINVAL;
return i;
}
static int mmp_clk_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
struct mmp_clk_reset_cell *cell;
unsigned long flags = 0;
u32 val;
cell = &unit->cells[id];
if (cell->lock)
spin_lock_irqsave(cell->lock, flags);
val = readl(cell->reg);
val |= cell->bits;
writel(val, cell->reg);
if (cell->lock)
spin_unlock_irqrestore(cell->lock, flags);
return 0;
}
static int mmp_clk_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct mmp_clk_reset_unit *unit = rcdev_to_unit(rcdev);
struct mmp_clk_reset_cell *cell;
unsigned long flags = 0;
u32 val;
cell = &unit->cells[id];
if (cell->lock)
spin_lock_irqsave(cell->lock, flags);
val = readl(cell->reg);
val &= ~cell->bits;
writel(val, cell->reg);
if (cell->lock)
spin_unlock_irqrestore(cell->lock, flags);
return 0;
}
static const struct reset_control_ops mmp_clk_reset_ops = {
.assert = mmp_clk_reset_assert,
.deassert = mmp_clk_reset_deassert,
};
void mmp_clk_reset_register(struct device_node *np,
struct mmp_clk_reset_cell *cells, int nr_resets)
{
struct mmp_clk_reset_unit *unit;
unit = kzalloc(sizeof(*unit), GFP_KERNEL);
if (!unit)
return;
unit->cells = cells;
unit->rcdev.of_reset_n_cells = 1;
unit->rcdev.nr_resets = nr_resets;
unit->rcdev.ops = &mmp_clk_reset_ops;
unit->rcdev.of_node = np;
unit->rcdev.of_xlate = mmp_of_reset_xlate;
reset_controller_register(&unit->rcdev);
}